Engineering Design Handbook. Criteria for Environmental ...

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CRITERIA FOR

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HEADQUARTERSUNITED STATES ARMY MATERIEL COMMAND

WASHINGTON. D.C. 20315

AMC PAMPHLET 16 zepLember 1971NO. 706-120

ENGINEERING DESIGN HANDBOOKCRITERIA FOR ENVIRONMENTAL

CONTROL OF MOBILE SYSTEMS

Paragraph page

LIST OF ILLUSTRATIONS ............... vuLIST OF TABLES .... ....... ............. X1PREFACE ............................... xii

CHAPTER I. TYPES OF ENVIRONMENT'ALCONTROL REQUIREMENTIS

1-1 Introduction ........................ ...... .I-!1-2 Temperature Lontrol ....................... .. -21-3 Humidity Control ........................ 1-21-4 Ventilation ............................... 1-4!-5 Control of Contaminants and Odors ........... .1-51-6 Noise and Vibrations ....................... 1 -

References ............................... 1-6

CHAPTER 2. TYPES OF INSTALLATIONS

2-1 Introduction ............................. 2-12-2 Floor ................................. 2-1-t 2 W.dI

2-4 Interior-extenor .......................... 2-I2-4.1 ingle-packap .......................... 2-32-4.2 Multi-eckage .... ....................... 2-32- 5 Muitiplc-unit ........................... 2-5

Renote Unit ........... ............ ...Reference .............. ................ Z2- 8

CHAPTER 3. TYPES OF MILITARY AIR CONDITIONERS

3 1 Introductiqu ...... ....................... 3-13- 2 Single- and Multi-packa Units . 1............. 1-13- 3 Configuration (Horizontal and Vertical) ......... 3-13 -4 ('ontinumnt and Intermittent Operation ......... 3- 43-5 Electric-powered and Gasoline-cngine-driven .... 3--63 6 Skid- and Trailer-mounted ................. 3-6

Reference ..... 3...... ....... . .. . .-


TABLE OF CONTENTS MCon't)

Parwnph Pare

CHAPTER 4. FEATURES OF MILITARY AiR CONDITIONERS

4-1I Introduction ... ... 4 1

4- 2 Service Versatility 4 14- 2.1 Cooling Capacity .............. 4 14 - 2.2 Heating 'CapLhility .............. 4 24-2.3 Ventilation ...... ....................... 4- 242.64 Colectivne ProteVction Compatibility .....i..... 4-24 -2. 5 Compatibility With Sensitive Electronic Systems . 4-34- 16 Tolerance of Variations in tho: Power Supp!y .... 4--34-3 Easm of Operation .. ....................... 4-34t-4 Mobility ............................... 4-34- 5 Riabllity and Durabgity .................... 4-44-6 Maintenance .............................. 4 -54-7 Installation .......................... ... 4-64-8 Storage ................................. 4-6

References ............................... 4-6

CHAPTER 5. TYPES OF MILITARY HEATERS

5-I Introduction .............................. 5-I5-2 Electric Heatenrs ........................... 5-15-3 Combustion Heaters ....................... 5-3

R'-nces ................... ........... 5-5

CHAPTER 6. FEATURES OF MILITARY HEATERS

6-i Introduction ............................ 6-I6-2 Service Versatility ......................... 6- 16-3 Ease of Openraion .......................... 6-26-4 Muh~ty ............................... 6-26-5 Reliab9ity and Dumbiity .................... 6-26-5.1 Otiec s ............................... 6-26 -_. Features Contributing to Reliability and

Duability ............. ..... .. ....6-6• Maintennce ............................ o-36- 6.1 Three Maintenance Categories ............... 6-36-6.2 Maintenance Tine Objectives .............. 6-46-63 Features Contributing to Eas of Maintenanc. 6-46- 7 Installation ............................. 6--56. 8 Sto age ........ .............. ..........

References ........................... . -S

CHAPTER 7. METHODS OF MINIMIZING COOLINGAND HlEATING LOADS

7- i Imution ........................... 7-1


AMttP 7tMI2

TABLE OF CONTENTS (Cn't.)

SParagraph Page

7 2 Reduction of Solar Load .............. 7-I7 2.1 General ... .......... . . .. .. ..... . 7 17-__ Reduction of Window Are. .................. 27-2.3 Shading ............ ...................- t

7- 2.4 Increasing Reflectivity of Exeinor Surfaces ... 7 37 -3 Independent Ventilation of Heat-rele~ng

Lquipnient .............................. 7- 37 -4 Recirculation of Air from Heat-releasing

Equipment ......... ................... 7-47- 5 Ventilation Independent of Environmental Control

System ................................. 7-67- o Elficient Lighling System .................... 7- 6

References ............................... 7-6

CHAPTER 8. CRITERIA FOR SELECTION O1ENVIRONMENTAL CONTROL UNITS

8-1 Introduction ........................... . . 8- 18-2 Perfommnce Requirements .................. h- 18- 2.1 Determination of Requirements .............. 8- 18-2.2 �onbined Hnin and Cooling Units vs

Separate Units .......................... 8- 28-2.3 Nonstandard Units ........................ 8-28-3 Electrical Liritations .................... .. 8-38-3.1 Power-supply OCaracteristics ................ 8-38-3.2 Power Rating ............................ 8-3ý8-3.3 Electrical Inteffernce ..................... 8-38-4 Physical Limitations ..................... 8-38-5 Transportation Livwi -tnou .................. 8-48-5.1 Mobility ................................ 8-48-5.2 Vibration .............................. 8-4

References ............................... 8-4

CHAPTER 9. INSTALLATION GUIDES

9-I Introduction .............................. 9-i9-2 General Arrangement of Environmental Control

System ........................... ..... 9_-9-2.1 Chor c ietww Free Discharge and Duct

System ................................ 19 -i9- 2.2 Location of Ewironmevntal Control Units ...... 9-19-2.3 lyp"a System Layouts .................. .. 9-29-3 Mountins Desi* ..................... 9-29 -3.1 Types of Mouni-4 ........................ 9-29 -3.1.1 Introduction ....................... .... 9-29-3.1.2 Throuetthe-wall Mounting ................ 9-59-3.1.3 Exterior Mounting ..................... 9-5

Wi


AMC* ft120

TABLE OF CONTSENTS I',on'.)

Pnras~h Page

- - 3. !.4 Interior-vxterior Mounting ............ .... 9 99 3 1.5 Reractabr e Mount! .................... 9- 99-3.1.6 tieater Mountiog ....................... 9-99--3.2 VibiJt!Qn Control ... .. ................. 9-99- 3.3 Exte ral Connectios ....... .......... 9-13

9- 3.3.1 Eleitrical Connectiorns .................. 9- 139-3.3.2 Condensate Drain ........................ 9 199-3.3.3 Fuel and Exhaust Connections .. ...... 9-199--3.3.4 Reirigerant Pining ........ ............. 9-249-3.4 Provions fm Trnsportation ................ 9-249-4 Air Distributitm nti (iCrculation .............. 9- 249-4.1 Introduction ............................. 9- 249-4.2 Air Distribution Systems ................... 9- 259-4.3 General Ru!.s of Ventilation ............... 9- 289-4.4 Methods of Av'oiding Objectionably High Air

Velocities .............................. 9- 289-4.5 Heating Systems .......................... 9-299-4.5.1 Air Distribution With and Without

DIauwork ........................... 9-299-4.5.2 Conditions in Polar Regions ................ 9-299-5 E&uct Desg .............................. 9-309- 5. 1 General Rules of Duct Design ................ 9-309-5.2 Design Velocitis ........................ 9-319-5.3 Design Procedure ........................ 9-319-5.4 Duct Fabrication ......................... 7-329-5.5 Supply Outlets ........................... 9-369-5.6 Ducts for Remote Units .................... 9-369-5.7 Selection of Duct Material .................. 9-369-6 Controls . ..... .... ..................... 9--369-6.1 Control Panel ............................ 9-369-6.2 Thermostat .............................. 9-399-6.3 Dampen ................................ 9-399-6.4 Auxiliary Controls . ...................... 9-409-7 Safety Cowvidetatiom ....................... 9-409-7.1 Introduction ...................... ...... 9-409-7.2 Combustion Heater Opention ............... 9-409--7.3 Emergency Override Switch ................. 9-419-7., Safety Prcautiom ........................ 9-A!9-8 Maintenance ftovis ..................... 9-439-8.i Introduction ............................. 9-439-8.2 Acc~ensib ity ............................. 9-479-8.3 Coding of FIo and Receptacks ............ 9-489-8&4 Protecxio Against Deterioation ............ 9-489-9 N"osie Contf.l .......................... 9-499-9.) Intoduction ............................ 9-499-9.2 Air Noie Control ....................... 9-499-9.3 Mechci¢l Noise Control .................. 9-50

iy


TABLE OF CO ENTS (QCWnt0

Ref.......... . . . .... .. ...... 9 53

(CIAPTEk 10. CXWLING OF ELECTRONIC EQUIPMENT

10 I Cooling Methods .................... .... 10-10 2 Computation of Cooling Requa-ements ....... 10, 2

Referenc .......... ..................... 10-4

CHAPTER 1I. CHEMICAL, BIOLOGICAL, ANDNAMAOLOGICAL CON'SiDERATaONS

11I- I Introduction .......................... ... I11- I11-2 C-nrud Cotsideratiom of Collective Protection... 1[1-3

11 -2.1 Kind& of Contamiation .................... 11-311i- 2.2 Airflow Requirenents ..................... 11i- 3

11-2.3 4ti ............................ 11-311! - 2.4 Perttm w ............................ I ! 1 -3

I1-215 Ckeso Rooins ............................ 11-411 3 Collezke c ftwti:or System Components ....... 11-4I -i.! Introd ction ............................. 11-411-3.2 Air Inlet Protector ........................ 11-511-3.3 Prefilter ................................ 11-511-3.4 Blower .......................... 11-511-3.5 Particulate Fiters ......................... 11-511-3.6 Gas Fdter ............................. 11-611-3.7 Filter Units ............................. I1-611-3.8 Control of Pre ure ....................... 11-611-3.9 Contrls ............................... 11-711-3.10 Protective Entrances ....................... 11-711-4 Installation and Mounting ................... 11-9

Refetrences ............................... 11-15

GLOSSARY ............................. G- IABBREVIATIONS ......................... G-4

APPENDXES

APPENDIX A- FUNDAMENTALS

A- The sychrowetk Chart .................... A-IA- 2 Overall W--t rarnder Coefficent .............. A-iA-3 Meav (i Reliability .............. ........ A-3

References ............................... A-3

APPENDIX 9. VESIGN CRITERIA

-I Clinwtk Desi Crikeds .................... .9-1


AMCP 7WI20

TABLE OF CONTENTS MCon't.}

P.•.ngrapthPa

B 2 Aflowa]e ('arbon Munoxd (concntrationsB 3 Noiw LveI Specifications .......8- 4 Effect of Noie on Verbal Coammunca3tio n 3

Refefencce• .... ........ . 4

APPENDIX C. DESIGN PRKO'EVURES

C- I -ta"trmnation of Envirow.rentWa ControlR[qu!, me nt .......... n...... .. .

C -1. 1 ntiofProccdul .. ..C- 1.2 Latent Heat Load Considerations ......

C. 1.3 Environnicntal Requirements for Equipmentan~d Activities . ................. "

C-- 1 4 Performunce Variation With Aititt,,b- ..C- 2 CalcuLation of Cooling Requirer-,ent .. 3C-3 Exampic of Air Conditoner Selection.......

C-4 Calculation of Heating and Coolingfor M.19 Van ............

C-4.1 Interior Design Air Condition ......... ..C- 4. 2 Exterior Des. Air Condition ............ (".C- 4.3 Heat Load C.Iculation .......... ...... CC'- 5 Alignment Chart for Calculating Coolin- Loads ... C-18

Refe•rences .......................... ... ( 20

APPENDIX D. AiR CONDITIONER TOPICS

D- I T-chnical Characteristics for Air Conditioning.Van Type ......................... . D I

"D- 2 Refrigerant Circuit With Hot-ps Bypass....... .... 1) 2References . ..................... ........ - 4

APPENDIX E. COLLECTIVE PROTEC-TION SYSTEM (CPS)FOR COMMAND POST VEHICLF

Reference .............. .. . . F 1

I


LIST OF ILLUSTRATIONS

Fig. No. TIdle Page

I I Cha.rt 1for IDct-rinining, lffective lempupatme forNormially ('lothed, Sedentary Individuals .... I _2

I2 Revised ASIIRAF Comfort Chart ...... .......... 1- 321 The loor-mounted Installat ions of

1 5,000 FBtu/hr Heater ................ .....2 TW 0io 0,00(0 vitt/hr hleate~rs Mounted Jriid'.

FExpansible Var' .. . . . . .. . . . .2) ,000 nm/hfr Air Conditioner Mounted Through

Wall of Air Trantsportahle Hut..................2--39 ,000 Btu/hr Air C'onditioner Mount d Through

Van Wa!] Witt, Half Iniside and Half Outsidethe Van............... ................... 2- 3

25 Frequently Used Configuration% for Mounting1 8.000 Btu/hr, Multi-package Air Conditioner ... 2--4

20 Illustrations; of Thrý!e Mounting C'onfith'.rat.-onsof 1 8.000 Btu/hr Multi-package Air Conditioner 2-_S

27 Illustration of' 9,000 Btu/hr Air ConditionerMounted Outside an Inflatable ShelterEmploying Flexible Ducts for. Air now .... 2- 6

2--8 View of 60,000 Btu/iir Gasol ine-engine-d riven Air.Conditioner With Duct Storage Compartment 2-7

3--1 Example of A,- Conditioner With SeparateConden-s.ýr and §-vaporator Se!ctions (6,000Btu/hr NMulti-packa_,e Air. Cinditioner) ........... 3-3

3 2 18.000 lltu/hr Multi-packagc Air Conditioner . ... 3_43-3 Two Examples of Sirgl.!J 1cg Air Conditioners . 3--5

5-- 1 60.000 Btu/hr Gasoline-burning Heater ......... -5- - 150,000 IBtu/hr Pot table Duc:t.'ype Heaiter .... 5--47- 1 Example of the Use of Shading to Reduce Solar

Heating of Air Conditioners ................... 7 -37 - 2 Method of Ventilating Heat-releasing Equipment

to Reduce Environmental Control Loads .... 7_-SuI Typical Air Distfihution Arrangements for

Traihkrs ............................ ...... 9-39_2 Typ';.--l Heating and Air-conditioning Installation

in Semi-trailer Using Vertical Ducts .............. 9--69- 3 Typical Heating and Air-conditioning Installation

in Semni-trailer Using Horizontal Ducts ............ 9- 79-.4 Through-the-wall Installation of Air

Condi' ioner,;...............................9-89- 5 Door-mounted Environmental Control Unit ...... ,9 6 Hinged Air Conditioner Mountinig Which Permits

Swinging for Servicing ....................... 9- 109-_7 Large Air Conditioner Mounted on Van With

Detachable Frame................. ......... 9_Il9 Installation of Multi-unit Air Conditioner..........9 - I 2

Vii


AMCP 706-120

LIST OF ILLUSTRATIONS (Con't.)

Fig. No. Tit. Pave"

9) 9 Wall-mounted lfeater and Air Conditioner in

Shelter .................................. 9 13"9 10 Exterior Mounting of Condenser Section of

6.000 ltu/hr Air Conditioner Showing PowerCables arid Refrigerant Lines ................ 9 14

"9 I !(A) Elevation Views of Air Conditioner andHeater Installation in Shop Van .............. 9_ 15

9 - I I(B) Inside Isometric View of Air Conditioner :andHeater Ilistallation in Shop Van .............. 9 16

9- 1I (C) Outside Isometric View of Air Conditioner andHeater Instdllation in Shop Van .... ......... 9- 17

9-- 12 Telescoping Rail Installation .................. 9 189- 13 Heater Mounted on Floor of Shelter ........... 9 -199-- 14 Floor-mounted Space Heater With Quick-

disconnect Fuel Adapter ................... . 9-209- 15 Space Heater Mounted on Floor of Shelter ...... 9 219-16 Pedestal-mounted, Gasoline-burning Heater ...... 9- 229- 17 Heater Fuel Line With Quick-disconnect Fittings. 9 -23

"--18 Clearance for Vibration Control inThrough-the-wall Installation ................ 9 24

9- 19 Method of Passing Power Cable Between Condenserarnd Evaporator Sections of Multipl -unitInstallation .............................. 9 25

9- 20 Method of Connecting Condensate Drain toAir-conditioning Uni ...................... 9-- 20

9-21 Method of Attaching Condensate Drain toHeater Exhaust Line ....................... .9-_26

9-22 Fitting for Connecting Refrigerant LineThrough Shelter Wall ...................... 9- 27

9-23 Arrangements for Protecting Exterior Openings inthe Envihonmental Control System DuringTransit ............ ............. ....... 9-- 28

9-24 I,1asic Air Distribution Problem ................. 9-299-25 Illustration of Poor and Good Duct Design ...... 9.319--26 Friction of Air in Straight Ducts for Volumes

- of 10 to 2,000 cfm ........................ 9- 339-27 Portion of Heater Discharge Ducl in Semi-trailer . 9-_379-28 Heater Duct Transition Piece ............... * *-399-29 Heater and Air Conditioner Installation Wilh

Connecting Ductwork in Semi-trailer .......... 9 409- 30 View of Semi-trailer Environmental Control

Installation .............................. 9- 4 19-31 Heater and Air Conditioner Discharge Ducts in

Semi-trailer .............................. .9 429-32 Completed Installation of I:ivironmental Control

Ductwork in Semi-trailer .............. .... . 9 43

Viii..


A 't." ýXj- IX Ut

LIST OF ILLUSTRATIONS (Con't.)

Fig. No. Title lakv

9 33 View of Ventilation System for Magneti-: Iape

U nit . ....... ..... .... .. ...... .. .... .... 9. 4 49 34 Interior View of Shop Van Showing l:lectronic

Equipment and Environmental Control Units ... V 459 35 View of Completed Van Installation ........... 9 469 30 Conversior Materials Required for Flexible Duct

Application ............................. 9-469 37 Drawing Showing Cani-lock Arrangement for

Conne-ting Flexible Duct to Plen!p ........... 9 47Q..- 38 Drawing Showing Method of Attachinz, Flexible

Duct to Female (onnector With Metal RingClamp ................................ . 9-48

9-39 %-'tachments for Attenuating Noise at Intake andDischarge Openings of Ernviron mental ('CntrolU nits .................................. .9 - 5 1

9-40 Attenuation of Noise in Discharge Ductwork ..... 9-5210- 1 Diagram To Illustrate Solution of Problem

on Cooling of Electronic Apparatu, ........... 10 3I - I Category A Collective lProtection ....... ...... 11 2I1 --2 Exploded Views of Two Concepts for Modular

Configurations of Coll,:ctive ProtectionEquipment .............................. 11 3

11-3 Recommended Gas-particulate Filter Unit((;PFU) Design Air Flows and Ranges ......... 1I1 4

1 1-4 Air Inlet Prote'ctor ......................... 11 5II -5 Straight-flow Dust Separator Tube Cyclone

Principle ................................ I ! 711 - o Cyclone Arrangements for Continuous I)ust

R em oval ..... ........................... I1 81 I--7 Typical Panel-type Particulate Filter

Construction ............................ I - )I !--8 Typical Lates!-design Gas Filt.,r ............... II - 11H --9 Air Purification Unit ....................... 11 - 131 -.10 Parallel Ar,nangcment of Three GI'FU's .......... 1 131 - II Antibackdraft Valves ....................... . I - 14

H - 1 2 Typical ('PE Air Distribution Methods .......... I1 1511 13 Schematic Drawing of Collective Protection

Syst•m With Booster Blower ................ I 1- I6

I1 - 14 Schematic Drawing of Shelter (olleciiveProtectior System With Air (Conditioner andFilter Unit Miounted on rrailer .............. 11 17

A- I U.S. Army Psychrometric Ch:rt ........ ..... .. A- 2B.- I Fffect of Noise, Separation, and Voice I Oe'el

-n Person-to-person Communiication .......... B--4C-- I Plan View of SI 4i Shelter ................... . C- 3C-.., Revised ASHRAF. Comfort (':arW ............. . C--10

ix


LIST OF ILLUSTRATIONS (Con't)

Fig \0 T-itle Npe

( • Psychtometnrc Probabdityhr"j ( - ilI( 4 Heat Source-. Smks. and Surface fieat

Transfer in M 29 2 Van ( - 12( 5 Extenor Surfaces of S129Q Van C 14C 6 Psychro-mtnc Density ('hat C 17k - Air (onditionng Load ( •ilulator Nomogaph C 19D I Refrigerant Flow Dagram D- 3E I Recommended Collective Protection System for

M292 Fxpa'ndable Van E 2


AMCP 706-120

LIST OF TABLES

Table No. Title Page

3 I Specifications of Military Environmental Control

U nits .................................. 3- 23-2 Future Environmental Control Units ........... 3-44- 1 Cooling Capacity Specification for 60,000 Btu/hr

Vertical, Compact Air Conditioner ............ 4-2

4- 2 Maintenance Time Objectives for MilitaryAir Conditioners .......................... 4-5

5-1 Specifications of Military Heaters .............. 5-2o --- I Maintenance Time Objectives for Military Heaters 6--49-1 Recommended and Maximum Duct Velocities for

Conventional Systems ..................... 9-319- Circular Equivalents of Rectangular Du%,is for

Equal Friction and Capacity ................. 9-349-3 Recommended Construction for Rectangular Low

Pressure Ducts ........................... 9-359-4 General Characteristics of Outlets ............. 9-389-5 Transmission Constants for Typical Isolators ..... 9-52I 1--I Dust Concentrations for Different Transport

Conditions .............................. ! 1-611-2 Existing Particulate Filters for Collective

Protection Systems ........................ 11 - 1011--3 Existing Gas Filters for Collective

Protection Systems ........................ . I 1011 -4 Standard CB Filter Units ..................... I1 - 12B-I Maximum Allowable Concentrations of Carbon

M onoxide ............................... B-2B-2 Maximum Steady State Noise Level for Army

Materiel Command Equipment ............... B-2B-3 Maximum Steady State Noise Level for

Nonelectrically Aided Person-to-personCommunication .......................... B-3

C-I Temperature and Humidity Requirements forTypical Equipment and Activities ............ C-2

C-2 Total Equivalent Temperature Differentials forWalls for April 20 and August 24 .............. C-5

C-3 Compact-'!nit Cooling Capacities (Btu/hr) at 1.0Sensible Heat Ratio and Free Delivery ......... C-7

C-4 Compact-unit Cooling Capacities and SHR atNominal Military Conditioned Air DesignConditions .............................. C-8

C- 5 Cooling Correction Factors .................. C--8C(6 Cooling and SHR Correction Factors ............ C- 8C-7 Conditioned Air Fan Performance - CFM ....... C-8C-8 Psychrometric Conditions at 99.9% Probability ... C-1 2

('-9 Corrected Equivalent Temperature Differences ... C- 14C-_10 rotal Heat Load Calculations. Summer

Condition: M292 Van ..................... ('-15

xi


PREFACE

Th, Engineermg Design Handbook Series of the Army Materiel (ommandIS 3 coordinated series of handbook; contaming basit information anifundamental data useful in the design and development of Army materieland systems. The handbooks are authoritative reference books of practicalinformation and quantitative facts helpful in the design and development ofArmy materiel so that it will meet the tactical and the technical needs of theArmed Frces.

The purpose of this handbook is to help fill the need for comprehensnmetechnical documents for regulating the environmental control of mobilesystems, such as shelters. vans. and trailers. As used in this handbook.environmernal control refers to the regulation of the temperature. cleanh-ness. and purity of the air in the controlled space, it also includes regulationof the noise and vibration genera!ed by the environmental controlequipment.

Following an introductory chapter covering the different aspects ofenvironmental control and a chapter on types of installations. most of thefirst half of the handbook consists of chapters which describe the military airconditioners and heaters, and the criteria for selecting them. A major chapternffers guides on the insta•t!ion. of en'rironmental control systems Otherchapters discuss methods of minimizing heating and cooling loads and thecooling of electronic equipment. which represent the major demand forenvironmental control in mobile systems. A final chapter considers coilectiseprotection equipment for chemical and biological contaminants.

Various design data and sample design calculation.- .. ... '"d tnappendixes.

The Handbooks are readily available to all elements of AMC. includingpersonnel and contractors having a need and/ot requirement. The ArmyMateriel Command policy is to release these Engineering Design Handbooksto other DOD activities and their contractors and to other Governmentagencies in accordance with current Army Regulation "0-31. dated QSeptember 1 96f Procedures for acquiring these Handbooks follo%

2. Activities within AMC and oth" DOD agenckes ordV direct on anoffictal form from

Commanding OfficerLetterkenny Army DepotATTN AMXLE-ATDChambetsburg. Pennsylvania 17 "201

3W


b Contractors who have Department of Defense contracts should submitthtr requests through their contracltng officer with proper justification tothe addte listed m par a.

c. Government agencies other than DOD havirg need for the Handbooksmay submit their request directly to the address listed in par a or to

Commanding (;eneralv. S. Army Materiel CommandATTN AM(AM-ABSWashington. D.C. 20315

d. Industries not having (Government contracts (this includes colleges anduniversities) must forward their requests to

Commanding GeneralU.S. Army Materiel CommandATTN: AMCRD-TVWashington. D.C. 20315

e. All foreign requests must be submitted through the Washir•!on. D.C.Embassy to:

Assistant Chief o6 Staff for IntelligenceATTN: Foreign Liaison OfficeDepartment of the ArmyWashington. D.C. 20310

All requests. other than those originaetig within DOD. must be ac-companied by a valid justification.

Comments and suuestions on this handbook are welcome and should beaddressed to Army Reserch Office-Durham. Box CM. Duke Station.Durham. North Carolina 27'06.

Xul


CHAPTER I

TYPES OF ENVIRONMENTAL CONTROL REQUIREMENTS

1-1 INTRODUCIiON Becci•e of the necessarily high equipmentdensity in many mobile military strutlures.

In its broadest sense. environmental •.ontroi the space -vailable for personnel may be lessentails reguTation of the temperature. pros- trbxq what is considered desirable for operatorsure. density. cleanliness, and putity of the effiwiency. It is, therefore, important to con-gas in the controlled space; control )f the trol the environment within the structure toconcentratiops of its componenlt, paiculry avoid discomfort. fatigue. and other condi-water vapor: the circulation and distribution tions that may cause degradation of human

of the gas; and also the control of noise and performance.vibration. Environmental control also involves

proviions~ ~ ~ ~Envro-n,-ental reqiirments (temperature.provisions for detectin g pollutants and wa rn- v n i a . n o s ) f r m l t r p b a i ning against their critict accumulations which aetle ,,fi, d noise) for military appbcatli nsc-uld cause humaH incapacitation or death. are spt ed in the standards published by theU.S. Art xy Human Enlgineering Laboe,•

The term "air conditioning" cowrs only trtes'" and also by MIL-STD-14722b. Thethe r€ocess of treatig air so as to control ps V-ary specificatioa is the required Effectivesimau.1nteously its temperature, nhui~aiy, And Temperature (ET). This parnmeter, which isdiMtrision to meet the requirements of the defined in the Glossary, combines the effectsconditioned space. of temperature. humidity. and air movement

on human thermal sensation into a singleAs used in this handbook, environmental quantity. In accordance with current military

control has two major purposes: design chtena for environmientaiiy cutro1spaces, the recomaneded El vadue is 81.3*F.

(I) To inovide a tolerabne habitat wher and the maximum allowable value is 85eF.

degradation of human performance is mi (The maximum desired dry-bulb temperatureand also to enhance survival under extreme is 90 0F.)conditions.

The effective temperature chart in Fig i -i

(2) To provide optimum environmental relates ET to dry-bulb and wet-bulb tempera-

conditions for materials and equipment opera- tures and air velocity. Fig. 1-2 illustrates the

tion. results of studies at th•e ASHRAE Laboratoryon the effect of emironmental conditions on

These conditions may be incompatible in the sensation of comfort.special cases. For instance, in locations wherefood is being pocemed. temperatures new the The major conditions regulattd by environ

freezing point are desiable to tetard spoilage mental control are elaborated briefly in the

while a room temperature above 6OF is paragraphs which fovvw. Several design aids.

favorable for personnel. In cames of such including a description of the psychrometric

mutually conflicting requirementh com- chart which is commonly used in air-condi-

promises maust be sought, however, the com- tioninig practice. are given in the appendices

promise must be in favor of the item it was of this handbook.

desined to protect-in this cam food; person- n - 0 W * in dw In onid can wear protective cklhing. .m CM-4.

1I4


Ia

ri

S//

444

/

do4 La'

vk~tto" o*So A-IL CANAA Ceg. 47 V4 emE M4? # .fv o 0 It f 100 944,gAY. w 34 ipewd fS 1766I

F*ume 1- 1. Chart for 0emmtniy Effecti,, Ty*r.eW e for Normaly Clothed.SederitWy ti* fAW Uopyripftwvv y A5II#Ar -;mnmt by pwer nsr

from ASHRAE Guide and Data Book 1967.

1-2 TEMPERATURE CONTROL Tabe 5-1.) In addition to the umi of elctriccombustion heaters. heating is sometimes

The most common form of environmental achieved by circulation of a fluid connectedcontrol is the regulation of temperature. to a thermal reservoir as. for exampe. in theUsually. a thermostat is used to control the circulation of engine coolant through heatei-addition or removal of heat as may be used in personnel compartmcnts of somerequired to raise o. lower the tempcnrature of military vehicles. IUmiled temperaturc contrclthe environment Can au - , - ,an; with

outside air. this is feasible when the tempera-In the type of enclosures considered in this ture of the outside air is low enough so that

handbook. heat is usually added by the use of the required ten., erature in the enclosure canelectric or combustion heatets. and heat is 1,c obtained with a tolerable rate of ventila-removed by the use of air conditioner%. Most tion.military air conditioners are in the form ofenvironmental control units which include 1-3 HIJWIXTY CONTROLeectric 1-hatia; elements. so that they ,in beused for healing as well as for %voling Humidityj• control is important because ofpurposes (The ,fsifieations of military en- its effects on both personnel and material.vironrmc al control units are given n Table High huflikdity ;Cduceý the comfort -f prepsA3-I. and those of military heater, firc given in 3nd causes many materials to corrode and

1-2


A"* MOVEMUE? on ufteutL(cC

So -

14

1 10

iflhe comfort dinfurs~Aon curt show that ade nwxkmtmn pmeeneW of poo~p* &#ow4 bewomlorftbs at 71 ET in maamw at 60 ET mn wi~nm Thm diuribtiva comw areb"O On~ Abe rMMOM Of P~WWM kn, wd&O4' aft., en a condiNomd lpmTO*AW haws VAms 3. 4. 5. mid 6) sOmw tho mcomm of v*.cem aftar &Aeximawgy hkwqhow Oc*Spmiwy. If itel a I A m rM ~l~ that OWSM will Ifel quit worm afittwMiea toan? eftomvn at 85 ET the mmxinim uW~ien on m""ur t^WOic Im

Firpm 1-2 Rei~f ASHRAE Comfort Chiwt Copyriftu by ASHRAE.RO"~m bY Puruvon frogi ASHRAE G"id aW D~a Book 1967.


decompose. Low humidity maty cause difti- some of the water vapor to condense. Whenculties in using certain materials. such as moist air passew over cooling coils. thete ispaper and fabrics. The increase of static insible cooling of both the (dry) air and the

Selectricity assciated with low humidity may water vapor, and dehumidification occurs

even initiate explosions in sonm environ- when the temperature of the moist air falls

ments. below the dew point. Most cooling coils

The amount of moistur' in an en provide simultaneotsly both sensible coolingatmospher depend on mseveral factors.the and dehumidification. In such a system. the

atmos re depends on sevorai factorus the amount of dehumidification which occurs ismoisture content of outside air • f dependent on the %ensible cooling load; and itventilation, the amount of moisture that may may not necessarily meet the humidity te-be added or removed by the environmenta quirement of the enclosed space. If notcontrol equipment. moisture that may be enough moisture is removed, the refrigerationadded or removed by processes crried out in system may have to be combined with athe enckloue, and on inoisture derived from sption 4ystem. or. if too much moisture ishuman respiration and perspiration. When 3i; removed. a humidifying system may have tohokld the maximum possible amount of be addedmoisture in vapor form it is said to besaturated. Relative humidity (RH) refers to Unlike what happens when mist air n,the actual moisture content of the air, e;i- cooled. then. is no change in moisture contentpremstd as a percentage of the maximum when moist air is heated - though generallyamount it can hold at a giWen temperature and the relative humidity is decreased.

preuure. The dew point is the temperature atwhich air with a given moisture cor, rntbecomes saturated, i.e., the temperature at Printing operations' provide an example of

whch its RH is 100 percent. Fig, 1-2 should an application in which humidity control is

be consulted for the effect of relative humidi- important. Adsorption and desorption of

ty on the comfort of penrsonl moisture can cause paper stocks to stretch orshrink; and when these occur mm-urnifotmly.

The controls of temperature and humidity the paper may become distorted. The en-

are intimately related because the saturation hanced development of static electricity in an

vapor pressure of water rises with increasing atmosphere of low relative humidity -may

temperature. Therefore, when the tempera- interfere with printing operation: on the other

ture of a given atmosphere is increased with- hand. high relative humidity can prevent

out the addition of moisture, the relative proper ink drying. Depending on the type of

humkiity decreases. The principal means of printing done and the natural environment of

raisi relative humidity are to spray the air the printing plant. separate control of humidt-

with water or to evaporate water into it. ty and temperature may be required.

Relative humidity can be lowered by chemical

means, though this is not an economical Computer installations are another examplemethod. More commonly, relative humidity is of facilities in which humidity control may belowered by decreasing the temperature of the important- Lack of adequate moisture in theair to be dehumidified to the dew point of air atmosphere can 'nterfere with the reeling ofhaving a moisture content such that mixture nagnetic tapes in computer machinery.with room air or. in extreme cases. subse-quent heated air brirg the proce'sed air to 14 VENTILATMIOthe desired temperature and humidity.

The purpose of ventilation is to renew part

Dehumidification occurs when air is cooled of the air in the controlled space to replenish

in an air conditioner if the temperature of the oxygen and to dilute pollutants such as CO0.humid air fait- below the dew point. causing obnoxiou* funtes, and odor

I-4


Venttiation and circulation rcquirements typically contain tarboa monoe•,r. oxides offor imltar) apphl.atonm arc spe~cfied by H[L nitrogen. and annmonia arr one source ofStandards. I-or communications systems and noxious substasices encountered ini militaryrelated eqwpment. for example. they awe operations. Another source is the exhaustgiwen asW products of cniges'b The maximum &Ilow-

able concentrations of these gases and other"-1 Ventilation facilities should prowide a pollutants Ifvapors. fumes. dusts, ett i can be

minimum supply of 1000 ftK of fresh obtained from the Threshold Lanut Valuesair per person per hour. published by the American (onfetence of

Government Industrial Hygienists. Maximum"2 Air circulation around the operator allowable concentrations of carbon monoxide

should be less than 100 ft per min and are gven in I able H. f. Appendix B.velocities less than 65 ft per nun aredesirablc. The removal of gases. vapors. odors. and

tine mists depeinds vet) much on their naturv"'S. Hot or cold torced-atr systems should an6 concentration. If the solubility properties

be designed so that the hot or told air perrmt it. washing or scrubbing is indicated.discharge !s not directed on person- Other forms of removal are chemica reaction.nel." combustion. and adsorption on an activated

solid substatwe suh as sihca gel and activatedWhere odors and furtles must be diluted, carbon. or alumina. Provision is usually srade

the needed level of ventilation can be con- for the rm.onstitution of adsorbent niatenals.siderably higher than is indicated in Item I. usually bý heating. Pa•riculate matter v, th

sizes dewn to i imcron in diameter such asWhen the temperature of t!- circulated industrial dusts. pollen. and bacteria--can be

outside air must be increased or decreased to effectively removed from the air with com-ment temperature requirements, vrentilation mon air filters. ISee Ref. 3. Ch II, Fig. Irepresents ma additional load on the environ- Spe.:ial high efficiency filters made of dass.mental control system. In cases where the or glass-asbstes. fibers-- are uc-essary forheat which has to be removed from a space is smaller-sized particulates' CBR* air filtersgenerated inside the space a certain amount tied by the military remove 99.97 percent ofof air cooling can be achieved by ventiltion rlticulatc matter down to 0.3 nmcron inwith outside air provided it is rot too hot or diameterhumid.

Activated charcoal is effective in adsorbingRecovery of recr.d.ulated air. as b) charcoal many organic %apors land some inorganic

filtration, can significantly reduce the te- gases) present in low concentrations. In addi-

quired outside air ventilation rates, producing tiong to removing obnoxious odors. carbon

substantial cost savings p<rticuiarly in sys- fliting is al-o effective m removin vapor%tems requiring large amounts of outsidc air injurious to health The latter properD. can beRecovery methods are diqcussed in Chapter enhanced by impregnating the Carbon With1 2 of Rcf. 3 and Chapter 65 of Ref. 5. The approprate chemicals for ab.wrbing the undc-economc asprct is treated in Chapter 80 of sired vapor.Ref. 4.

The mechanic% of the removal of radio-1-6 CON4TROL OF CONTAMINANI8TS AM active contaminant' :s esscntiallh identwal to

ODORS the removal of parliculatcs and ga.es Addi.Air contaminants art clasified by thlir tional problems. howcvct are pose4 by the

physical properttio as dust. fume, and smoý c. accumulation of radioactivity in the fi~tcrmists and fogs, atid saplxrs andf gae ae (,awsproduce-d when weaponr are fired which "R .

1.5


material. If filers are uwd with electrical of of vibrations for equipment are spevifted bymechanical equipment. the concentration of the U.S. Army Human lknginpering Labora-radioactive dust may create a health hazard tofies.m ' (MIL-STD-10OB. Ref. 2a. speci-and, th•rCby, require special tandlng. The firs %ibration and acoustical noise tcsts.frequent filter changes thus made neces•ry, among others, for military equipment.) Refs.with the attendant radiation hazad and 7 and 8 may be consultei [or guidance indisposal proolem, add additional burdens on methods of noise controlthe personneL The accumulation of radio-active Material on filters can be alleviated by There are essentially three sources of noisethe use of inertial dust separators, which can and vibrationseject approximately 92 pc=nt of the particu.late matter before the air is passed through a (I) Sources exterior to the controlled area

42) People and equipment inside the con-if filters are used to remove particulate trolled area

matter, their effect on tie overall environ-mental control sytem must be evaluated. For 03) Thlb environmentai control equipmentexample, the pressure drop across filters itself.increases the required fan power; also, it maybe necessary to remove some of th- moisture The technical literature on air conditioningadded in air scrubbing or washing operations usually concerns itself only with the last itembefore filtering. Here, the chief sourres of noise are motors.

compressors, and fans. The noise enters intoMore information on odor sources and the space to be controlled via transmissson

their removal can be found in Chapter 12 of through walls and other solid structures. andRef. 3. Chapter 65 of Ref. 5. and Chapter 80 through the air ducts. Noises from motors artof Ref. 4. effectively combated by proper anti-vibration

mounting. Sound attentuation in ducts result%1-4 NCE AND VOSRATIONS from absorption at the walls. reflection at

openings, and reflection at elbows. Lining theEnvironmental control also includes effec- walls of the ducts with absorbing material

tive means of dealing with nose and vibra- further increases the sound attenuation.tions. Noise creates discomrc-rt to personneland may. at excessive levels, impair their Maximum noise levets specified b) theactivities or even their health. Vibrations Army Materiel (ommand for personnct-offect not only pemionel but also equipment. occupied spaces and maximum notre levels forsuch as optical equipment and delicate me- various grades of speech intelliSibitlity arechanical apparatus. Maximum allowable levels Oivtn in pars. B-3 and B-4. Appendix 8.

REFERENCES

I. Standards of U.S. Army Fngineering b. HEL Standard S-2-64A. Hluman F'acttrsLaboratories, Aberdeen Proving Ground. Engineering Destgn Standard forMd.: Vehicle Fighting Comnartmenrs. June

1968.

a. HEL Standa-d S-1-63B. Maxmum c. HEL Standard S-6-66. IHuman FactriNoile Levei for Armny AkletWi Conm- Engineering Design Standard fopmn d Equprnt. Jime 1965. Wheekld 'ehicles. Sept. 1966

1-6


V ~AMcP 71%120

d HEL Standard S-6-68, Hiumban /-4 toot A'4H 1R M 'audi and Dala HI)l~, .Ip;pfus-Ebnglar'tifme Oesign Stradard fu om (iniI.'p /~Iv'-,, .t. jo', Ainct S~k ofrnunicafkt,n Sistertun and Relat,, dic .y~ Rtrigrtatinyi) jjrj ~i~ofdstiofl-Equipmnr1w c. 190~8 itlfItinl. z' Ir -\f, . A )1 Orb. N

2. Miii?3ry Stan ards NIP% ".44f vPiJ Data A .%ilrnpu

a. tIL~STL)-8108. 1.,: ro'anetua eiit Rcrmam cn ~udonn.etfhudi 15 Junic 1907. N'tit. 1 21)Oct b~ . It 9w) I 'It ,' rco ( It ai Inn Ro ciy Se I

ficitrnW Pipi;ng 3rt;J Air( (ndstionaflg. %tof

b. MlL-STD);4-. 11u'pra' Inginteering2 4j4 SpIt'LVestgn nrleria for 3.%iilart .5 ;:r'nEquipment, and F'artitie5, 1) 1-~ vb 1968.a~ "~ .Jtii~i t.,a

liall Ho ~~~YzI

3 ASHRAE. Itandbook ul 1-undamenta+'Amer. Soc o'f 14cating. R-ofrigterating and %I( Him.", I j lJInJhbI'.~ (,/ %13Air-Conditioning Enginieers. 1m . e or~ M", Iraw-Hill Hook (o nm. c%York. N.Y.. 1967. York I ~~s


CHAPTER 2

TYPES OF INSTALLATIONS

2-1 INTROOUCTION more efficient use of avazablr sp-. Pioi-

taom for air-sjndwtioner nu)unting ha•e bvrnEnvirconmental .ontrol units may be made in sotre van and shelter dc ,gn,. %uit-

mounted in a variety of ways. the choice abie frmie ,flgratens are med. anti rib%depending on the type of enclosure being z- designed to support one or two .sx:controlled, the type of environmental control conditioner,, hi somx ,ases. knockout panel%unit. and the conditions under which the are provided to simplify through-theaUll in-system is operated. Fhe aim is to make stalktgion.efficient use of space- to provide for con-venient maintenance and operation; and to The simplest wall mounting ior single-meet the service requirements, including limi- package air conditzoning units is providcJtatiorns on noise and vibrttion. In this chapter. when the unit us mounted with the rrar of thebrief descriptions of the common tyes of unit outside the enclosure and he front olinstallations am accompanied by figures illus- the unit inside the enclosure Some installa-trating them. tions. however. may requtre that the unit t-,

all inride or all outside ot the enclosure in2-2 FLOOR such cases. ducts are needed to aciomplith

the necessary air floi4. and. witere cooling t,If space is available, ,loor mounting usually req tred. the heat of compression must tve

providis the simplest type of installation, exhausted to the outside atmosphrre Ihcespecially for the larger units, since it elimi- most commo-1 apphcation of wall mounting i%nats the need for special supporting struw- at the front vntf o. an ,-aclosure. usual,% intures, It is not recommended for the snaller the upper half of the wall. where tlhcre is aair conditioning units because, unless modi- minimum of rterterence with vperationsflied. the air outlet and controls would not be inside the enclosure and there is no inter-convenient) located, and the units inherently ference with the cab of the vthicle in the cas,are more easily wall mounted. For heaters, of truck-mounted shelter, Side wall tounthowever, floor mounting is appropriate for Prg is not desirable if the umi must protrudrthe smaller, as well as the larger units. through the wall. Fig >-3 illustrates a uailLocating warm air supplies on or near the mounting on a transportable hut in which thefloor helps to prevent stratification of room unit protrudes through the wall mhen in tue.air (as does locating cool air supplies near the but can be withdrawn into a recessed pos•tioncedihnf Fig. 2-| illustrates three floor- during transit when the un;: is not ,eededmounted installations of a small heater, andFig. 2-2 illustrates shelf-mountLng of a largeheater. 24 INTERIOR-EXTERIOR

2-3 WALL A sligh; reduction in tP' requtred coolingcapacity and blower power of air conditioners

Wall mounting. including intecrim and ex- can be achieved by mounting the condensertrtvr.•, is the most common type of mounhng. section extenally and the evaporator sectionPaz•:cularly with smaller units, it rermits in the wall or. better. inside of the controlled

2-1


(Al Heater mntkiled in (B) Hleaetr insWul6an in (C0 hwwu u#mtsw inpoilabk phowop.phc mnbile ground ,tajn dwthelt Showing ex-dark room i va (see comtnrction van sut 0w yArrowl (WYiAC ru*WAtinj pgfdov fe Sri//

Figure 2- 1. Three Fioor-mcnted Instollations of 15,000 Brulhr Heatrer

Figure 2-2. Two 60,000 BwuAh Heaters Moumnted Irarde Fcpwwsibe van


t|

(A) Unit in opemi*ng positton (8) Urqt in trarsit p•ovon

Figure 2-3. 9,000 Btu/hr Air Conditioner Mounted Through Wall of AirTrwsoable :u (A special frame allows it to be rolled

into recessed position during transi r.

space. However. the prime advantage of in- 2-4.2 MULTI-PACKAGEtenor-exterior mounting is greater installationiersatility as described in par. 2-4.2 Greater installation %ersatiht) is provided

by environmental control units built with2-4.1 SINGLE-PACKAGE separable sections. Some units have separate

condenser and evaporator sctions. and oneRefer to par. 2-3. =ir, 2-4 illustrates this (18.000 Btu/hr! unit is constructed in five

type . instalh!in -n the cas of a laboratory sections comprcsor, condenser. condenserdarkroom var fan. evaporator, and evaporator fan- The

sections can be scparatcd and placed in man)"different configurations. mxking the unitcompatible -with a vanect% of structures. Fig..

-5 illustrates different t rk-s of installationpossible with units having scparac ciaporatoraano condensr sections. Fap, >-5 and 2-1illustrate sone of the installations possiblewith the five-section unit.

A multt-package air conditioner is recoie-aended for structures where large mountingholes would weaken the wall. When theevaporator -n. a mounted in the conditionedspac. and the condenser on the outidc. the

Figure 24. 9.000 Bru/fr Air Condition-€ oDii wall opcning r-qurred is a >- to --m.Mounted Through Van Wall With dianmetcr hole foT passage of refrigerant and

Half Inside and Half Outside the Van elcctnrc lincx

2-3


4IFA

Feque 2.5. FreqwJnflI Used Contpra"tion tol Mounting 18,000J Stu/?hr,A(,dd-pwcke Air C*,ndhtionw

2-4


each carn/n a fcwtiop cl the la'd. Anadvantage of this type of instation is thatfailure of one art: *oes not diaiulc the entire"V•,'l; as Iog as at leg one unit emauinsoperable, the "ystem can meet a poriton ofthe ± A comparable single-unit iutallationwould resut in co.pTI&L- !huY4-n- r ofailure. Fo& appfhctions in which a disruption

Sin full erice is intolerable, a multipte-unitinstallation should be used with one or moreunits as standby in case of failure of anoperating unit. Multiple-unit installations mayalso be applied to systems which encounterlawge variations in load requirements depenel-ing on the season, geographical location, oroperating conditions.

"- - 3t Occasionally, special consideations in-cate the use of a multiple-unit instaUaion.

R •e 1 u For example, the conventional 18.000 Btu,'hr""envuonental control unit (Table 3-1I.weighs more than two of the conventional9000 DtuI'hr units Therefore, in this case atwo-unit installation would nave the advan-tage of weighing less than a sinile-unit instal-lation.

S • , ITo avoid excessive power s$rs in inul-taple-unit installations, provision shoud bemade for a time delay between the starting of•• . ~individl units.

"A practcal examnple of a ta-w.nut ippiica-tion to a sheter is given in fSeL 1. . thethermostat of one a- conditioner was set at

Rk. the desied temperl um kvel. and the thermo-stat of the second unit was set about V Fabove the dered tempeatwe. This made ontunit operate full time while the second unitcycled on oly un-d extreme conditions. Lt..when the tenipertue was too high for the

Fipure 2-6 fIkhjsratiom of Tha ,ooitr feist unit to handle the toed. With thisConfJowbm of 18,000 BtuStr nrgement there was little dmaner that both

Multi.tckcage Air Corditiow umt would start imultarous•. causing alar po•we drain on the gnerator. As indi-

2- MULTiPLE-UNIT cated in a preceding pararaph. unkls th, isa -"cal wamnpanent as just described. multi-

When the heating or cooling load is sub- units would have to be turned on in sequencestantial, and especiaBy if the load is variable, to prevent an excesive power surge whenit nay be advisable to we two or more units. starting the system.

2-5


24 RyM • Remote environnental contrW u moyIn some appfictons it mkv be advan- be mounted on srad traiers or an W•eso

tsagous or ev"• nww to mout the skid& Type arrangments wre shown in FOqDIeswonmmatal coMrul unit remote from the 2-7 and 2-& Usmally, flexible ducts are eed

space being conba&. Rcame mounting is for ask flow between the enyvnmnental towOeniEw Jf I! WOOMture is not strong enough trol unit and the controled encosure. Re-to support the unit as, for ewsanvi, in the mote-control pael connected to the umi bycae of an inflatable shdter. A uqwantety- cable permit operation to be controled fromSunit s •m p ."Ml a nd witta the endoure. Heat trans•r throuhwpeeds installation for riwl-rected stuctures. ft walls of the ducts inacases the requiedEcononasa af realized if a seperately- heating or coolg capacity of the unit, andmounted unit can service sreeral structures friction omes through the ducts im theWhich do not require l-time opMtioM. blowr power required for a given flow rtme.Remote mounting also makes more spece To minimize both effects the ducts should beavaiable for other uses within the controlled insulated, and they should be kept as Ohort

strucure. nd asstraight as possble.

! "T

Fioure -7. iMaltivn of 9.00 w#f*r A* Comndrw MounOutsid an l-ff•W Stmh Entowiny Fmxibe Ducts for Air Flow


AMCP 706-120

'JIJ

2-7


IAK AM~?11120

I REFERENCE

1. W. MI. Imlen. Ret 4,,wi1~naw r f' wphitPlai" mcm ciawn (n . (Anffrj,,, An I--ore ix c NacwI' s Shefte, I cchima4 Rqxwrt No. York. Auwi~ IM96 f AD~sx 7 SOU i

RAD(-Mr-04-30P. Rortiv Atr i)cvcdop-


CHAPTER 3

TYPES OF MILITARY AIR CONDITIONERS

3-1 INTRODUCTION Ref. 8 lists the units in Table 3-2 for tuturedevelopment

The military air conditioners of interest totapplications covered by this handbook have 3-2 SINGLE- AND MULTI-PACKAGE UNITScooling capacities between 6000 and 60,000Btufhr. They are listed in Table 3-1 which Environmental control units arc avawlbic ingives some performance and physical data for both single- and multi-package configurations.military environmental control units*. More As the terms unpl). the singe-package .,nitsdetailed information on the configuration of are completely self-contained in a unglc cawasthese units can be obtained from Ref. 1 which and the multi-package units are separable intohas draisingp of exterior views of the units. two or more components wiuch :an bvThe design and testing of some of the mounted in a variety of configurations Ihccompact. horizontal units are discussed in simplest multi-package units am- those -Ai%.hRefs. 2. 3, and 4. It may be noted that all of have separate evaporator and condenser -.-the compvact units and many of the cninen- tions. such as those shown in Fig. 3-1. Ticnorta units arc capable of heating -- by means two sections are connected b. electnijlof electric heating elements - in addition to cables and flexible. quick-disconnect. pre-cooling. Environmental control units intended charged refrigerant lins.- A more complexfor future developmnent, probably aftet 1970. multi-package configu& tion. shown in Fig.are listed in Table 3-2. 3-2, has five separable sections in addition

to the condrnser and evaporator, the con-Whecevr possible, the stanAad units Listed denser fan. evaporator fan. and compressor

in Table 31 should be used in designing ane mounted in separable sections. Multi-air-conditioning systems. Units of 6000, package units with separable sections arc iN.o9000. and 18,000 Btu/h cooling capacity are discussed in par. 2-4.those used most often ? loads are Single-package units have the advantage oiusually met by installing multiples of the being morne compact and hghtnr than multi-smaller units. Specaai units can be developed packag units of eual capacit' and cor-for unusual applications only if sufficient lead pwabk design. As illustrated in Figs, 2-5 andtime is available. Occasionally, it is necessary 2-6. multi-package units have the advanit; ofto use commercial units for these special greater instalhtion %vrsatility Other advatt-applications, t:Ages of the multi-package configuration in-

clude the reduction of inventory investmentIn addition to the Carnlcs Iofnemm tal a made possible by the fact that ontunit titscontrol units.which fames ofisted in Table 3-many applications and the rapid repair attain-control un'it. which ate listed in Table 3-. able by simple replacement of defectis sec-

tionsOU•bmw DWmi O bustb t ok#W, MA o at 3-3 CONFIGURATION (HORIZONTALviW. MmilWk I by Ow FeduaI Swck Rumbae, Me avikfW P4MUM11•es,, Acm AND VERTICAL)

UThe availability of air conditioners in both

3-1


I

! t,

""q4 . 4 4q 44

Mill::lii Ili~lIi M!f PUM

Its $I ,,,,,,,,,,* ,,,,,,,,,,,:- .--" ,:,,'"---.. '- 4i)

--ill zI Atllli t I :W049

l i l I

• --


~VINT-tNlIa

AMU

i AM

CONDOENS EVAPMaATOR

IA) MOWd 4/f wirOrWe~a air ccvndidocvv

Fiqwe34. Exampfe of Air Conditionrw With Separae Condenserand Emporator Seaions (6,0061 Otu/hr Vulti-packaW Air Conditiower


horizontal and vertical configurations facili-tates fitting the units to the available space.The horizontal configuration is suited pn-marily to window and wall mounting, and thevertical configpAration is suited prim•aiy tofloor mounting. Air flow paths for typicalhorizontal and vertical single-package units EVAPOAT1O 1are shown in FiLL 3-3.

COMMiSEM FANTAKLE 3-2

FUTURE ENWROUMEUTALCONTROL UNITS c0*9SSG

(1) Thermoelectric Eni:rwonmental ControlUnit. IP 000- 24,000 Stu/hr, 208-V. 3-phas, Figure 3.2. 18,0W Bru 'hr Multi-ack60Oanc4 400 Hz gte3..1,08r hMut-ac•

Air Conditioner

S2) Waste Heat Powered Entironmental Con- ori w m t ei ni introl Un01. 60.000 Btufhr contnuois operation. (ontrol s)stenis inmo.!-

in, internuttent operation are uimpler tnd(3) Mobile Utdit" Moduies. 18.000; 36,000; cheaper than modulating system, hut in60.000 Btu/hr (Cooling) many military app#;cztbons. the pouev )urm, '

that occur whtn motors ae turned, on or offThe modules will provide cooling, cannot be tolerated in other equipment shar-

heating, and auxiliary electrk power. ing the same power suppW. In such cases one"They will provide also for inclusion of must select unitt, provided with modulatinghot water heating .-d prexurized air controlequipment when these are specifically One method of modulating control used inrequired. air conditioners is automatic cyclnmg of rcfng-

erant alternately through the evaporator sod(4) CompactMultion Air Condftioner. 10-15 and a bypass, depending on %tether or notton (120.000- 180.000 Btulhr). 208-V, cooling is required. This actucvs contro! of3-plase. 60 Hz discharge air temperature while allowing th<

compressor. condenser and evaporator motorsto opetate continuousl). Another method of

3-4 CONTiU AND INTERMITTENT modulating control is to vary the rate of anME•ATION flow by means of a variable speed fan or

adjust3bk dampers.To keep the environmental conditions in

the controlled space within the desired litnits. Control systems having continuous fanoperation of the air-conditioning equipment operation. with internmttent cooling. tnvole amay be controlled by either o V4O ii•ethods. humidity effect which may not be acceptableOne method involves the intermittent opera- i some applicstions. When the cooling cods

tion of a corrlonent, such as a compressor or are cycled off. the continued fan operationa fan, so that refrigerant flow ot the flow of causes recvaporation of water from the cool-air across cooling -.,;, respectively, is turned ing coils and the drain pan. resulting in lhgheon or off. The rmethod of modulating controlinvolves varying the rate of flow of refrigerant *A"vw0%d powe, .• , nt, -, dwad ,- ra, t'

3-4


COLLECTIVE PIOTECTOR EVAP•RATOR SECTIONMiET IWHEN ATYACHE1o

OUTSIDE VENTILATION RETURN (ROOM) AIR

Aill WHEN REQUIREO)

I'l 60.000 tu ',hr a,ood•ttoner

COU4OENSMRCOND•ENSER AIR

ACONDENSER

FR1ESH All

RETURN AIR901i

(8) 9,000 Btu'hr aw condfti0wv

Figure 3-J. Two Examples of Sinje-pockap& Asr ConJitioner3


fimniuity inv the occupied space. Unless the stallation can be mounted on skids or trailers,h•,'!e. ,idity can be tolerated, continuous as illustrated in Fig. 2-8. These portable

r- )I ,-,•iti'n should not be used. mountings lend considerable flexibility to

installation, and they also facilitate the han-3 : L3 L•CYRIC-POWERFD AND GASOLINE- dling and transportation of the controlled en-

FNGIN*E.DRIVEN closures. The choice between skid and trailer

mounting depends on the service required.nmij:itary air conditioners are designed Skid-mowited units can be placed directly on

K, •, ';I operation when connected with the ground, but it is preferable to provide a

lpply indicated in TFable 3-! The base to prevent trouble due to snow, rainwh!w•-, aii conditioners are also designed to water, and other deleterious conditions on the

w)t.iitt fiont power supplied by military ground. It is necessary to provide for the

ý'i•,t•~t(os. When system power is limited or loading and unloading of skid-mounted unit-t)•. •;l•c:•tionl requires an air conditioner onto and from the transporting vehicle.

o)LfltL.J (,, a trailer or skid mounted, a Trailer-mounted units may be located

,0) 00O lBtoi hr gasoline-engine-driven unit is wherever room is available, consistent withm-.liklbl.. power and ductwork requirements; and they

At the present time, only a special, are easily relocated when necessary. With

60,0OO-MB/tur air condi-tioner is available as a trailer mounting it is usually possible to

ga~olinc-cngme-driven unit. provide space on the trailer for auxiliaryequipment such as ductwork and collective-protection filter units. Hauling a 'trailer-

3-6 SKID- AND TRAILER-MOUNTED mounted unit over long distances, especiallyover rough roads, might be more cumbersome

Air conditioners intended for exterior in- than hauling a skid-mounted unit in a truck.

REFERENCES

I. viditairy Standard (Preliminary), Environ- Report 1918, Army Mobility Equipmentmental Control Units, Performance & In- Res. and Dev. Center, Fort Belvoir, Va.,,tallation lData, U. S. Army Engineer Re- Dec. 1967 (AD-665 368).wearch and Development Laboratori',s,Fort Belvoir, Va., Rev. October 1966. 4. D. P. Swan, Nominal 60,O00-Btu/hr, Com-

pact, Horizontal, Air-Conditioning Units,2. Nominal 18,000-Btu/hr Compact. liod- Report 1932, U. S. Army Mobility Equip-

zontal Air-Conditioning Units. Tech. In- ment Res. and Dev. Center, Fort Belvoir,lobrmation Rep. 33.1.4.2, University of Va., August 1968 (AD-676 119).Pittsburgh Research Staff, Wash., D.C.,NMarch 1968 (AD-830 057).

5. AMCR 701-6, Logistics Responsibilities,

3. R. P'eterson. Nominal 36,000-Bltn/hr, Corn- Assignment of Environmental Control andpaet, lHorizontal. A ir-Conditioning Units, Refrigeration Equipment, 4 April 1968.

3-6


AMCP 701&120

CHAPTER 4

FEATURES OF MILITARY AIR CONDITIONERS

4-1 INTRODUCTION tioners which are to be used in militaryapplications wherever possible, and it gives

I he puroose of this chapter is to describe the procedures which apply when special"Yolle of the general features relating to the purpose equipment is necessary. Generalstorage, transportation, installation, opera- specifications of the units are listed in Tabletion, and maintenance of military air condi- 3-1; information on the featwes of militarytioners. air conditioners can be obtained from the

Military Specifications listed there. AdditionalThe desilyn objectives of the group of information, including the discussion of prob-

compnact military air conditioners, which corn- lems and their correction, can be found inprises most of the military family, include development and testing reports and operat-minimum size and weight, standardization of ing manuals, such as Refs. I and 3 throughcomponents, minimum power requirements, 11.and maximum relability and maintainability.The features of compact conditioners include (2) Ref. 12 describes the environmentalrugged construction; capabilities for auto- conditions, including climatic doign criteria.matically controlled heating as well as cool- that are to be considered in the design.ing; for conditioned air delivery against development, and testing of materiel by theappreciable back pressure; for ventilation with Department of the Army. Environmental re-or without cooling or heating; compatibility quirements for materiel of the Mobilitywith collective protection systems; and self- Equipment Research and Development Centerprotection against abnormal temperatures, (MERDC) are clarified in Ref. 13.pressures, anrd loads; and against cutoff ofcondenser airflow. The hot-gas bypass type of (3) Ref. 14 includes specifications of somecontrol system is used in the units for precise of the tests used for determining the resis-conditioning without cyclic disturbance of its tance of equipment to environments peculiarexternal Llectric power supply circuit. to military operations - such as temperature.

humidity, fungus, salt fog. and vibration. Ref.Par. D-I, Appendix D, taken from Ref. I, 15 gives the MERDC vibratior. .. st procedure

specifies the general technical characteristics for air conditioners.required of van-type air conditioners designedfor military use. A description of the refrig- 4-2 SERVICE VERSATILITYerant circuit with a hot-gas bypass controlsystem is given in Par, D-2, Appendix D. 4-2.1 COOLING CAPACITY

The full rated cooling capacity must beAlthougn the air-conditioner features are delivered at ambient temperatures up to

amplitied in this chapter, one must reter to I120°F, with the return air having a dry-bulb

other documents for more detailed informa- temperature of 90rF and a wet-bulb temper.

tion. Some pertinent references are: ature of 90 F aly a w nt b y teature of 750F. Usually. as shown by the

example in Table 4-1. the sensible coolingI I) Ref. 2 lists the family of air condi- capacity is specified as a percent of the total

4-i


TABLE 4-1

COOLING CAPACITY SPIECIFICATION FOR

60.0%) BTUIHR VERTICAL. COMPACT AIR CONDITION'ER

(ram #Miwaiy SpscfAlioa MIL.A-U2S15MO))

Ev ,aeA hAnt SmuI.k Cco-"

Ammnst Total sorPma~tar. Tot. of TC ,w

F mnes C001i" cc"- CASiemvtDofw rY Seab Dry Bull) *a BUtt city. %Sti

A 120 9 75 6u 60000

C 95 80 67 65 60.000

.oolng capa,.at) tor ,_ifferent ambient and hercnt to ihýs ollecinc protectiton syý-tem 1oreturn conditions, be compatible with collective protection. air-

condit; -z units ha~t the

4-2.2 HEATIr•G CAPABILITY

I I There must be neglipblc ir 1akageAll of the compact units and some of the from the evaporator when under precsure

conventional units have thermostatically con-trolled eiectncal heating capability in addition (2) Lsc of a blo--throuah eraporator ?anvo the cooling capability. On some units. an ari a pull-through condenser fan i, requiredclectral interlock prevents operation of t-ne to help proent leakage trom the oatside toheaters dunng cooling, the conditioned --ide If the dpp I d 11 -n

a coliCtJre protector vs exposed lo the

4-2.3 VENTILATION outside air. it must be prssunrzed to asoidrecontamination of the suppl) air

When cooling or dehumidification are notrequired. %entilation can be obt,:. •J b-opening the fresh air inlet damper an -.dperat- 03 Travs and check salfs are required in

ing the evaporator fan alone. Whti .ooling is the Lo.,densjlc drain%

required. fresh air can be introduced asdesired by adjusting the ilet dam-per

141 Head presure .on'trol is requ.n-d it',permit op-rat.on on %.oohn! in io- ambient

4-2.4 COLLECTIVE PROTECTION C'-ý'- temperature Cooling ma% be req-ired everPAW ULITY with lo% ambient temr.erature if the internal

heat generaton i% high enoriuh Accordingy.For installations requiring prot.tiors the hiead premurc Lontro! %s~icm ri designed

again•t chemicaJ. biological, and radioactive tit flood part of the condenser and maintaincontamination. unuts are provided with a condenser pressure when the ambient temTer-separate inlet for connection to a collective ature drop, .x) lov. that the pressure differe-protector filter unit An auxiliary evaporator tti d,,rkr, th0 esaporator expansion valveair blower may be required to overcome the bcrt-)ome, ton small to induce the floA ofstatiR pressure loss and ductwork loss., in- refnrerant needed to sauisf. the load

4-2


411-2.6 COMPATISILITY WITH SENSITIVE put most units into op.-lawan, it shouEJELECTRONIC SYSTEMS suffice to connect them to drain lines icon-

dernwte lines in the c.oolinS mode) and theElectromagnetic radiation ciranae±iaS from proper electrical power soure. A siraple.

eictromitchaical equipment can interfere readily accessibit selector switch should allowwth~ zhe operaton of sensitne electronic the opefator to select easily the heating.equipment. Such tnterference can result, for ventilating, or cooling mode of operation. Iney~mple, from the current surges generated the cooling or heating mode, the enclkiairwhen motoi-s start and stop. Features which tempvrature should be aulon~xically con-reduce such interference arm trolledi by an adjustable thenmottat. Simple

damper adjustment should permit control of(1) Use of a hot Sas bypass for temper- the amount of fresh air entering the enclo-

sture control eliminates the stopping and sure.restarting of the compressor aftez the Ifintialitart. thereby preventing current surges. This The use of principles of human engineerin,systei , is described in Appendix D)-2. in the de-sig of the controls makes them

easier to use. Standardizvt.n o1 controis(2) Use of a pressure equalizing, valve and permits personnel familiar with the operation

electrical control of the starting sequence of of one unit to opmstc other units in the sauniefan and compressor motors minimizes cu tint famnily without !idditional training.

surges during the initial. manually-actuated t ho aigtmet ihscstart- Safety and ease of operation are enha~mcd

by providing moving pans and parts SUbjeCC

(F control devices such as main power line guards if they present a hazard to per-sonnelandsheddcb.

7 THE PCW&R SUPPLY of the compressor. when units are itrutil1

su.pply. Typical requiremnents call fo~r 60 cps

ratcd frtquencv at voltages between 95 and performance and communication of personnei10 pei%..nt of the rated value. in the conditioned ý.pacc. Quiet operation is

needed for intelligible conversaton 41~tna4-3 EASE OF OPERATION voice levels and for satisfactory ese of tele-

phone and open microphone-peaker systemns.Miiayair cuaditionern are &csignd fo In sorme cases-. e2l!temall sound attenu~to- airr

maximum practicable eaw of operation. To needed to satisfy the noise requiremcnt,-

PWL tm e itim*Rma Caeol abn muz* bt #dtUdMuEIt i gew (MM the rthn O't of the r4M =*- t The inobiltay of in'itary air-conditioner' it.

sbhdied "~ a tWkA-of puate enhanced by design &catures which lower the

4.3


size and weight of the units, by arra nnnts I I Self protection

which yield high rcstiance to shock andvibration. and by provumon of lifting and tn} Ovcrtemperature cutoff for htertie-dowa devices. Canvas covets can be pro- elementv•ded to prooect the condenser side of theunits during transit. Canvas covers should also (b) O(erpressure cutoff for compressrbe provided for the evaporator sections of and overpressure refrigerant release device,kid-mounted units during transit.

(c) Antifrost control for evaporator coilThe accelerations and vibrations which

envirc rimental costrol units am required to (d) Automatic cutoff when ambient-mthstund ca-t be toutd in the Military Specti dr-•. ibelw -_ db•!a-- . n,--

fications refernced in Table 3-1. which also mumlists the size and weight of the units. Corm-pliance with the specifications isurwes tt the (t) Ohvrcurrent and winding overheatunits are capable of withstanding loads asso- cutoffs for motors (To avoid needless tnppingciated with transport over rough terrain with- of circuit breakm used in cutoff circuis. aout ecqwung pump-down+ and blocking or tone delay dependent on the magnitude and

te-uown of internal components. duration of the current overload is em-

ployed.)

4-5 RELIABILITY AND DURABILITY (f) Phase sequence reina for 3-phase

unitsThe reliability cbjectvts for mditary air

conditioners are (2) Construction to withstand salt fog.

rain. misture condensot"on. fungus. inmectMI, Missuon reiabmhty* of 95 percent with attack, dust. sand. and high ambient temper-

Si mission timr ,), N4 hr ature and humidit.

(21 A mean-time-between-failures* of (0 The use of a filter-d•rer irn the refng-

1 104 hr w;th 0'0 per~ent confidence erant circuit to remove mosture. filter nm-

3) A rice life of 10 yr. with 4000h purities. and act as an acid neutralizer(3tweA .oiaerhieouls..wth400h

between overhauls. (4) Hermetic compressors

Although the mean-tim- -betwcen-failures is 15 i Hot gas bypass temperature controlimportant. it does not suffice to give a totalindication of system reliability. Equipment ib A rng sccured to cabinet and electncalreliability also imolves the case of repair and totors to present abrasion of insulationthe simphcatt of pre.entive n 'ntena.ne pro-cedures. These feature, are d&scusscd in par. C7) L se of high temperature soided joint,4-6. ;n the piping to reduce the p.svAbilith of

leakage an the reirigerant ystemFeatures now avaaiable which contribute to

the durabilit. and rehabdit' of military air IS) Permanent type filters. i .ones whichcan be cleaned b) washing or brtshing and

returned to w-',%-

S4t) Tube fin coali

S"m pmp 4-3.Appe-t•A. I 10I ;•se of an cectritcal mnterlfck to pre-

4-4


vent ormtion of the heaters when the ak for routine Service is less than 5 percent of thec.aditi,'•r is wt for cooling, COgkting til

(4) Motors and compwrwe are lubricated414t 14MI•TENNE for life so that no routine lubrication is

The maintenance requirements for military

air conditione-rs arm given in Table 4-2. (5) In some air 1nditionm, the

Some of the features now available which sor is mounted on a frame which can be slid

p to achieve t reqrments and whih out like a drawer to facilitate its removal.

facilitate maintenarwe when it is roquied are:(6) The cledtncal imucon box is Arranpd

(1) Interchangeability of as many compo- to permit removal from the unit to facilitate

nents as possible among the environmentai servicincontrol ums in a family should be the rune.This re,.quirment reduces not only the supply (7) Major electrical components are con-costs for s-pare pam but akso the trainit nected by MIL-STID connectors to facilitaterequirements. Personnel trained to perform repemnaintenance operations on one unit canpersorm the ayme function on othc' adnits of (8) Fixed anchor nuts of the floating.the same faly with titl if any additional ekin type used to facilitate mainte-tramaing nance and to reduce the number of loose

pans.(2) Access panels are provided to facilitate

maintenance. Greater facility is achieved if 99 The number of different types a Athe filter and maintenance access panels afmounted on spring hinges which cause the

doors to close when released is kept to a minimum.

(3) The permanent type air filters, which (10) Drawings are furnished for each non-must be inspected periodically and washed s standard military component. including thenecessary. are the only items that requie smiJllest pams.frequent attention. The filter cleaning opera-non require !ess than 10 min. The out time (II) A single refrigerant. R-22. i used in

all units in the compact family.

TAKtE 4-2(021 The refrigerant system includes s.r-

MATENIANCE TWA 0oSCTIVES vice valves to facilitate p-eventrve mamte-FOR WLIARY AIR COU•TM•IS naie checking.

O(ar cr 13) A liquid line sight glass ineucatesaMd Okme Gome wehether there is moisture in the reffigerant or

C* W6waSin I I I pWL a shortage of refrigerant.PIsgini. 1 h h

Men-T,,,e- (14) Number coding is used in the wong.

(15) Lifting handles or attachientu ame

Moan-Tim.- provided to faciliate dsnnomaoning %rith safetyto- Rap.' 4 8 24 if trouble shooinjg is required.

4-5


4-7 lNSTAULLATM (4) Provision is made for the attachmentS~of ducts.

The following are some of the availablefatumt which facilitate the imstalation of (5) Provision is nmde for remte mountingmilitary air conditioners: of the control panel and the thermostat.

(6) The stde surfaces of the units are free1!) Unts of each cooling capacity are of air apertures and Maintenance access panch

avzilble io vertical and horizontal contfgura- to permit sidc-by-side installation.tions to facilitate accommnodation to theavadable space. 48 STORAGE

Mihtary environmental control umts must(2) A choce of power soutce type is meet the requirements of Ref. 12 got static

available. exposur to salt fog. ra-n. fu-igus and insectattack. and blowing sand and dust withoutundue deterioration or excessive cleanup are

(3) Mounting is facilitated by lift fitting. startup time. Environmental control unitstie-dowrs, ard built-in attachment devvs. must also be capable of storage w-ithoutCaptivc nu• are provided in the base and damage at ambient temperptures from -65' Fback of the units. to 15MF.

REFERENCES

1. R. B. Sherfy. Nominal 36.000 Bruihr. 4. R. L little. Air (ondtuvneri v v#'wb

Conrenitmd. Standard Weigt. Single- Bliuihr, Muln-Package. 1,1,-ioht fVk-cic

S.ection. 208-svit. 3-Phase. 00-cycle and 20P!4.-zt'h 400-s ch 4-wirc. Tech-(Model CE36HBC6-208i Aw-Condition- nical Report 1695-TR. U. S. Armn. Engi-srg Unit. Report 1854. U. S. Army neer Research and Development [abora-Engineer Research and Development tories. Fort kivoir. Va_. I Sep emberLaboratories. Fort Beihotr. Va.. May 1961. (AD-272 179).i "66 (AD-485 823L).

5. H. R. Lopez. Engyneenng Report o!TwokSecnon. 36.10,91 Stu hr 4tr-O(ndi-

AMCR 701-6. Longttcs Responsibilities. tinning Unit. Technical Report Ioi I -TR.Asugnment of Environmental Control U. S. Army Engineer Research ar : De.Umits. Including Air Condtioners. Refft- velopment Laboratonem Fort BeMo'u.crators. flea irs. Fams. Blowers. and Va.. 23 December 19.59 iAD-232 9031Dehumidifiers. 19 May 1964.

6. 0. Oidbcrg. lEguneer LDksgr Te..t Report3. P. E. Chappell. .ominal 9.000 Btuihr. of a 9.000 Btu hr Sphll-Mountng. (6n-

Compact. iertical. 230-rolt. Single- rentional-Ti-pe Aier Conditioner. RepornPhase. 60-ticle (Model CE)I VAL6-230i 1836. U. S. Arm% Engneer Research andand 208P-motl. 3-Phase. 400-cyclk (Model DInevlopment Laboratones. Fort Bihotr.CEl I 'AL4-20P') APt Conditioning Units. Va.. Novcmber 1%65 (AD-1,." 301Report 1841. U. S. Army Engineer Re-search and LDevelepment Laboratories. 0 1. Oldberg. [)eeloprnnt ,,tn t it 1IfBtuFort ld-o4r. Va.. December 1%5 hr. Gas",lne-L"ngne-DnIer,, Ifult-fAD-631 325. va kagr -itn (•,nditincr. Report I 7%.

4-6


AMCP 706-120

U. S. Army .nierResiearch anid 1)c- Ii 11 McDulnakl Und L.H. Adkins, Eng(-velOPrllunt Laboratorie~s, Fort eldvoir, it crnfg Repori of' 6, 0OO-BLui//r A ir Cot-Va., '28 January 19055 (AI)459 445). 1-oii 11f TcnclRpr

J 7(J9-IR, U.S. Army Engineer Research8. J. F. Rylleska, lintil Report o! Sf'rvthe and Dievelopmnent Laboratories, Fort

It's of 36,000) Bti r,/j 60-cyciv, Single IBelvoir, Va., 1 5 March 1962 (AI)-283P'ackage, Jiorizontal, ConeflonlI0iel h'pe 204),.,fir Condiltioner. U.S. Armiy Airborne,Himcronics antl Specjial Wailare Board, 1 2. AR1 74-3K, lWvxurti.lkr, ii': 4Fort Bragg, North ( ablitia, 28 Dec. I 904 ~ und Luiltiaton of' M¶aterwi for !f'xireppi(AD-487 491 L). ( tdhiSMy19.

9., .J.,Smih, Nmine M,01ý itrih, 1 3. U. S. ,Armiy M'ý)hility EquItpment Rc-9 C.I. S ymjl , :V ppiIial i6, 00 I i ('/Jr..ýJ L II m idj~ D evelop mnlL m t C en ter., /5,: irm i-Comnpactl, V'ertical, 208-t'olt, .,-1'ase, me ,ittd I'quiremieni, for MaterielI of fllu'4 t'- vdc' (M/odel (T10) ~'4 L. W) nd Molr'ijify' Lquipmen''t C(v'untr, Letter of 2820H-L'olt, Y Phase. 400-vcvch' MAodel Jall. I 965. Research. D~evelo~pment andCI:40V,4L4) A'ir-ComditioninK Units, Re- l~niti~tccring iDirvcctorate. F-t. Belvoir, Va.por" 1 861, U.S. Army Engineer Research

and D)evelopment Laboratories, Foi 14. MII-SlI)-8101J. Liznmiroinmwnu( I esBelvoir, Va., June 1966 (A[)-638 011), 31 ,hod&, 1 5 June 190J7, Notice-I. 20)Oct. 190)9.

10. TNI 541 20-295-15, Air ('on dtiP.',pr,Ifloor Mfounting. ,If ir-( ooled W00, /lJ1ite/ 15. Tcý, l'w~cu/ire' V.\ 1.54 librawiv: t!.S.P r, 20N '/4Pe volts .50/60 cycle'. .- P/mve, Armay Mobility Lq uipment Research anoCarrier 11ir (and/hloning (Co. Model IX'~v~e~pmcn(i ('-iiter. Fort Bekoi,jj Va..76E3.1410.4, 7 November 1906, Novvinher .1'47.

4-7/4-H


AMCP M130

CI•APTE R 6

TYPES OF MILITARY HEATERS

5-1 INTRODUCTRION As with air conditioncrs. heaters ý.an be

tnstalled in a vanety of wa) s. i.e.. thc• can beMilitary, heaivi- consist primarily of elc- mounted on the floor as shown ui Fig. >-1.

tric. combustion, and automotive types. A and small units can be mounted on shel, spa•cebrief description follovs as shown in Fig. -2. Heaters .an also b<

skid-mounted and trailer-mounted.

t i lecrnc lleaters. Heat as generated by All heaters require electrical power forpassage of current through a resistive element, their operation. even if ori) Ln the controlMost of the electric heaters used in mobile ciucuitrv. In most cases, an external powersystems employ a blower to draw air over the source as r-qwred. but engine-dnven uits ,anhot element and discharge the heated air into be completely self-contained, with a generatorthe space to be heated. as an internal componerat. Several of the

military heaters are listed in I able 5-i Al are(2) Cw usn !icakrs. Heat is g rted combustion hcaters thich require pow'er on)%

by burning a fuel. which is usually gasoline or for auxilar) puroses , as Lonutoi and thea diesel fuel. in heaters designed for mobile operation of electric fans and fuel pump,systems. A heat exchanger is u, :d to transfer One of the units dcscnbed in P-r 5-3 11- iheat to air which is then discharged into the 5-') is of this type.space to be heated. Exhaust gapes are ventedseparatel) to prevent contamination of theheated air.

5-2 ELECTRIC HEATERS(3) 4utusmone Heaters. Most automotive

heaters are designed to make use of waste A vane., of requarements ha~c handh-heat from the engine, air being heated by a capped efforts tow-ard %tandArdization ofheat exchanger through which the engine separate electric heaters. Heaters expiwted tocotlant flows. Automotive heaters arc de- be available in the near future ha%e relaticl.%signed for use during transit. while most other small heating capicites. 4nd their chde use ishea•t" are n s; ed during transportation of an spu,, hlaur*n L.nits ot 1,gt-r capacit% arethe equipe•nnt in which lhe) are mounted, expcctcd to be deocloped

Automotive heaters may be used to suppi)heat either to a vehicular component or to the Although clctm. heating systems havecrew cem;a2nmem. lowe; overall cconomý than combustion

heaters. theq have %scsral advantagesThe famtiles of military heaters are tisted in

Appendix 11 of Ref. i. which gives the logstic (I ) Dectrc h.-attng is clean.responsibilitmm for eritronmental controluits. Technical data and the characteristics 42) The absence oL cum•justion productsof military heaters are liven in a prop-.d ebhrmnates the problem of their disposal andMilitary Standard2 . A summary of heater avoids the danger due to toxii. .ses such asspecifications in Re(. 2 ts lsd in Table 5-1. carbon monoxidr.

S • 5-1


AMCP 706-120

A~ Z.

T z~ x

w rr.w

cc~~~..

< .,-r'

-7 k

a2 U

LL

4,§:CR8

c

4 'S is

.- ~ s

-4p

al w~ f


AMCP 706-120

(3) With electric heating there is no fuel- up to 68,000 Btu/hr are to he developed, theNpd:igve problem, thus there is less danger of maximum capacity available in existing elec-c mVi,, a fire that, there is with combustion tric models r, 13,600 Btu/fir. Therefore, atheating, present it is easier to meet high-capacity

requirements by the use of combustion(4) An electric heater is much more simple heaters. Another advantage of combustion

in construction and control; therefore, more heaters using liquid fuels is their capability ofreliable and durable than an equivalent com- providing quick warm-up. The blower-type11mtion hcater, heaters arc the ones best adapted for use in

mobile structures such as vans, trailers, and(5) 1Ise of electric heating reduces the shelter,. The nonblower type, in which heat is

possibility of an occup'v"J compartmenn being transferred by radiation and free convection.:orittarninated during a CIUR attack. is better adapted "or use in putliafietit strui -

t u res.5i-3 COMBUSTION HEATERS

"lo further illustrate the features of com-As shown in Trable 5-1, several combustion bustion heaters, two units are describcd in the

heaters are available with capacities between paragraphs which follow.15,000 and 60,000 Btu/hr; and one gasoline-engine-driven unit has a capacity of 150,000 Fig. 5-I shows a 60,000 Btu/hr compactBitu/hr. Although electric heaters of capacities heater designed primarily for use in mobile

(A) Side aend left and view with heater positionod fordischarge-down Installation,

...... . (6) Side and right end view with heateq positioned for"discharge-up installation

(C) Configuration of heater

"Cae- be either or both. depetding apon installation ad position of control swltrh eard damper,

Figure o5-. 60,0O Btu/hr Gasoline burning Heater

5-3


t, , s, tlough not during transit. It is a shelters. The heater is mounted exterior toF. t,1•-z.ing, forced-hot-air type oi unit. the, shelter or other equipment to be heated

S I P"arrangnient purnits variation of and ls connected to it with flexible ducts. Asrecirculated air to fresh air. The shown in Fig. 5-2(A), it may also be used to' by used ai a ventilator when heating support air-inflated shelters. ThV heater is a

)I, f ,-•ired. By relocation of several 1!asoline-burning, forced-hot-air type of unit.a - li conponents, the unit may be The air-discharge blower operates continu-i c t:I f,): air discharge from the bottom, ously, and the combustion cycling is con-

F, A Fuel may be fed to the heater trolled by a thermostat. The heater electricala , : -1 ttnk eithcer by gravity or a fuel circuit is powered by a built-in generator. The

prime mover may be either a gasoline engine(Class 1) or an eiectric motor (Class 2). A fuelhows a 150,000 Htu/hr heater pump furnishes fuel to the engine (in Class I

,, pi mnarnly for use with military units) and to the heater combustion chamber.

HEATER FLUE

.• J£ET GOAF) EXHAUST

., , .AIR DISCHARGE

S[• ENGINEJ E XHAUST

~~~~i .,A.• C".•ItG/

elffiN (M ]rJ ENGINF (..00111JC.•'.*= •

AIR IN (CLAS I OtNLY)

(13 ('(onuration of (lass I, engine-driven. (A) Heater inflates and supplies heat to shel"S1,_' is r motor-driven,

Figure 5-2. 150,000 8tu/hr Portable Duct-type Heater

54


AMCP 70M20

REFERENCES

1, AMC'R '701-0, LoiqlYfics 10,'sioallsibiliiv•s. Vehicular Comparlinent. 1',,aters. Coolant,

Assign'nent ofl,'nvironmental Cimirutl and Engine; heaters, Space: Technical DataRefrigerations Equipfuwnt, 4 April 1908. and Characteattics, U. S. Army Mobility

Equipment Command, Fort Belvoix, Va.,2. Proposed Military Standard, Ileatvr',, 19 June 1968.

5-5


AMCP 706-120

CHAPTER 6

FEATURES OF MILITARY HEATERS

6-1 nldrRODUCTION fuels instead of a single fuel. These mullifuelheaters may be operated with aný grade of

Many of the general features of military gasoline up to 100 octane or with diesel fuelsheaters are similar to those of military air of classes DF-I, DF-2, or DF-A. The heatersconditioners which are discussed in Chapter 4. may be designed to be used primarily withTo avoid duplication, this chapter concen- one fuel, but multifuel heaters will have thetrates on those features which apply specif- capability of operating with other fuels whenically to heaters and does not elaborate on the most suitable fuel is not available.;eatures common to heaters and air condi-tioners. More detailed information catn be (2) Operation in Extreme Cold. All mili-obtained from the references listed in the tary heaters are capable of starting andfollowring paragraph. operating at ambient temperatures down to

-50°F, and many down to -65'F.Ref. I sets forth the responsibilities for,

and the general overall policies to be followed (3) Ventilation. Blower-type 1mlitaryin the design and development of heaters as heaters are capable of providing ventilationwell as other environmental control units, with or with'ut heating.This regulation may be implemented in thenear future by publication of a proposed (4) Col.ective Protection Cinipaiibil-Military Standard 2 which will supply data on Ity. Some military heaters can be installed sovehicular compartment heaters, engine cool- that fresh air taken in for ventilation passe,ant heaters, and space heaters in the military through a colective pjotection system. Forfamily of heaters. The document will include example, all of the environmental controlphotographs, installation drawings, and data units in the compact family (Table 3-1) arepertinent to application, supply, and mainte- compatible with collective protection sys-nance. Ref. 3 specifies procedures for some of tems.the tests used fur determining the resistanceuf equipmeut to environments peculiar to (5) Comnpatihilit)' with EIlcctronic SY.iytcn.mmilitary operations. Military Specifications on Saine Power Supp•y. Military heaters are(such as Refs. 4 through 7) should be con- designed so that they will 1ot intCrfcre withsuited for detailed information on the design, the operati,,n af sensitive electronic hy.tchesconstruction, operation, servicing, and testing powered by the same power supply. to helpof indiidual units, assure that there wil be relaively little cyclic

disturbance of the power supply. blowers ate6.2 SERVICE VERSATILITY usually designed to run confirluMusly. A!so.

thet electrical systems of military hcaters areThe available features desc.ibed in the designed for electromagnetic compatibili),.

following paragraphs enhance the versatility This means that the heaters will nitither emitof military heaters, significant electrical disturbances nor he %ts-

ceptiblc to the types of disturbances thai. may(I) Mullifuel "apabillt'. Some military he emitted by other equipment inl their

heaters are designed for use with a variety of vicinity. (Tile electromagnetic interferenceI b- i


Ahla 70&-120

suppression of military heaters is goveit::J by fuel hose connections on combustion heatersM 1L-STI)40) 1.)

(7) Reinotable control panels for con-(6) Tolerance of Power Supply Varia- venient location

tions; Military heaters are designed to beoperable under more than normal variation of (8) Instruction plates with adequate in-the voltage and frequency of the power formation to facilitate curr~ction operationsupply. The specification, for individual unit'should be consulted for the allowable varia- (9) Conveniently operated damper con-tions and the accompanying reductions in trols.capacity.

6-4 MOBILITY(7) Outdoor Ins allagion Kits. Some

heaters are designed primaAly for exterior, The features which contrabute to theand others primarily for interior, installation; mobility of military heaters art similar tosome of the latter may be obtained with kits those of military air conditioners. Militarywhich permit outdoor instaliation, Parts con- heaters are. constructed to withstand tietained in such kits should include flexible shock and vibration ot rough road travel,ducts, duct adapters, exhaust stack, fuel tan, Mobility is also enhanced by compactness,flexibl,: fuel hose and can adapters, and power low weight, and by provision of lift andand thermostat cables. tie-down devices. The use of ducts of the

compressible, flexible type belps conservc(8) Orientalfio jur Operations, Of partic- space during transport. Normally, blocking

ular interest is tile possibility of operation of and tie-down of internal components arc notthe 60.000 "A u/hr heater in all upright, necessary, neither during transport nor duringinverted, or on-the-back position after re- normal operation, However, suitable bracketsorientation of various internal components. are provided in ýomic engine-driven units

which require that the engine be tied down6-3 EASE OF OPERATION during transit. Some combustion hcaters are

capable of operating during transit of theMilitary heaters have a number of features, installation,

based on human engincering, which con-tribute to case of operation. These include": 6-5 RELIABILITY AND DURABILITY

(1) Toggle-switt a starting and shutoff 6-5.1 OBJECTIVES

(2) Standardized controls The reliability objectives lor militaryheaters aof-;

(3) Automatic regulation when connectedwith suitable thermostat (I Mission reliability of 88"; with a mis-

sion time of 250 hr. at a confidence level of(4) Ability to start and operate while 9(Y;Z**. In so,;w cales the fli.ssin may CorvIY

vibrating ol two 125-hr r lriuds seliarated by I hr ()Ischeduled maintenance.

(5) Low noise level7i 2000 hr betweeni major overhal.ls

(6) Use of vJick-disconneA. self-sealingS.... .: .......... 0 ) Availabl~i) ty of ')N';.

"aNol Al otlitary heateri Iivr 4i1 fdo hie I1qq14E f(ru n I #r . ...... ..esamiplr. Ilaturel (I ). (6). (7) and (9) mge not avaIabtl gin INot all of flit available |irater nme..i tlit....c o t-lhe itI 00 t1iu/hr heater, and fetoure, €1) and (6) tre rot U"elialstit and tiiisgn time at( defined in jim .available tin the 60,000 ltu/hr hestir. Appendla A,

0-2


64&2 FFATURES CONTRIBUTING TO RE- of heater =nma wreac are huted in the paw.UAWALITY AND DJRASSLITY 022ts wtuct follow.

AvaWiiuc iafetý aind sdjl-peviection fe. aIn-nattiure)i which hrlp nwct thc pfcviously statedobjctAiwes include a obsinHae~

i I iuLharc air ovehtca utof t (1) Reil fuel lank.. (%ot nocessary for

(2) ~utord ailre ctot- fvehrclt beaten if fuel is obtained from nmai.) lflit(Wifailre utof rak on vehile.k

3 ý 141e falur cutft -I Inspect for accumulated dirts around(4)Autwaw comuswituhariber heater. in =-intufake screen. in fuel screen or

purge cycl-t after manual cutoff fle n la fncmr

i)m otor oiverheat cutoff (3) Inspect housing, ducts, fuel lines.and wiring for looseness. breaks. cracks, or

ioi Electric~al fubcts or circwst breaker- to other damage.

proe~ Ieleinaloselodsb. bmnne-coo1kim-uperatrd Jieatern. N r

i Provwson of tenclosures. ot guards for rotn waitenance required.moving parlt !hut aught he a ha3ard to c. Eketnc Heater Inspect for loose con-opestiting or maintenance persanne! nectons. damage zu witrd or phurxg and lea "- in

t;~) Prowtecion against a-cci&nAi contict housin, connections. or hoses

with ct sufaces2. Orgmtanziaune oir Drec z Support Main ge-

(14 Enclosure of clectncally-enerpzed WC

parts and provision of grounds as requireda. Coimbustion Heater.

10i Hcatcr ducis c.apable of handlng ax: Relcigti.fncsar.it rughcr than norrnaý' tempnreaures i elc gue.i eesr

11 Ie of~t~nles stel ia cobuson 2ý Replace preheat resstor. if aicers-cn~rr~bers and mnun other parts sat).

i I _') ( onstruwtion in atxorancc *ihMh (3? Adjust or replace flame detectmrTarN Spc mfILsnjons go~cnung remsistance to f-witch. if necessar3f.sit-tog, ri-a. moisturc condertsation. and duest (41 lnspei darMpe frntrols and -and sand t

i I i L we of filters in t'ic fuel Lines tn aid in tEw *voear etrremoving mfle's~urc and other foreign matter-fromn the fuel 04.'VncwttoCt

66MAMTENANCE -

"6.1 THREE MAINTENANCE CATEGO- CL o tuat ot tan and heat-I

RIES


AMP 7I20

14) !nspoct dgasipeT t~nru3 And rcpzu. "2 "ANTEI'iANCE TIME OWECTIVIES

The JWaSOcflarilc tunw objecutrw for mil.-Pr Iant I/ra:er^ tary ficatern aft pv~en in fakt),- 1.

iI, P Repai or rrplace cord or plug if 6-6.3 FE~ATURES CON4TRIBUTING TOr-C--Aq -EASE OF MAINITENANCE

(2) Inspect anid clean heat echanger. 1-caturr- 'Ahici onUftributIc to ea-sc of1 iflai

131 1 nbpim mounting i~cup tihe teD~n--c intlutk

it nees~if). 11 Lkvdclpmcant of zinlt?,) hctc.te dcuagxaswith morrdct:vi drawing's .wmnin i maxi-

14 Regno~c 4nJ rcpUa,.c entire hcater ni mum twrchAngeabdirtý of p..im and mini-necessary. mumn frq~uirmcntis tor sparg: pdri *stxký.

15) lnmpcct damper contiol and rrpw~. ( I Permaninct iubri~itin -41wic !iubn,.aif ti~e r ork b rcqutuacJ

3 Ou'et or ,, .e.neral Sz~pp(*rr ~ 3, vuniber iaa of dcctnJ.a wiringI \ ormailw Nea~sepdJ

(4) Rcet jrT,.Lnf!ank' to ta~ilitatca. 0,mbm~izon fleatri di%mounnnpg when n~c~cný

(I i Rcmo-.c hcater from instlaliaon. 15~) provligon ,I Iip-. for "guiding 1,pare

dibassemble. clear, .an8 iwspe-t internal and fuset. cgncn.-enzJ% kx.s. tfig: iand thitexternal pans. holds the ot-vrating lusn%

I 2i Replace deteriorated pans. 4(('i Lwe of .3ptsic. quia-&isconrine-fastcnanp on ~ovcr,ý or p~lcts trial mu,-! N

13) Read,-usi and ret.:ahbratc asng.e. remo~cd for adjustment or repair oper-at~ion

CiProvision of linsinLtionf P1.4tvs Integralh Lngtnr.-.t wan-i-,tperale.J Hea~ter' with tnc heatcr, ind reidiIk ac~,e'-'.jb sind

readable (not %ubjt%:t to otliteratior I gxi~irlI11 Same as Item (II i or .ombustxo,,i imprtntj %crzn.m prgxcdurcs. a' mt

heaters. ind wiring thigram,

(-') Replace heat exchanzer. fan. motor.or motor hrus-hes, if necessar TABLE 6 1

MAINTENANCE TIME O&JECTIVES FOREk/c tit Ieaters MILITARY HEATERS

I4I) Same as lien; 9t for ~ombustion Opmwow Du~c Gen"8

Crw SivP S"vW

121 Rtpla~cc heating element. hcal cx A#i,.v T tIw12 1000 3000LhinMe. fan. miotor. or ;switchci, if noccmarý rwor

431 Rec.alihrate or replace thermnostat. if Met-T:o t- 4c


asiernbly of paU. in wrung timbinatinumfr~

4 9) Lkig~n ý(musdcm~tiom~ wtik-h min~linic~t (61 Budl-t in aslncr of othdr provliorb

n~ecesut to hold hcd&%-y or swkwjid pam tot nuunhtinsduring AUb~nb1) Ci AvadabitI) wvith diitlcrcnt ekcctnsi.A~

fINULciflrilb. pcmulttuig adaptation to Am67 *NTALLA~ON .nttu1p4cd wour~c!ý of powcr

Ithc vcns-t±ilt) of hc.jtcr i, "t414tir. vs O il uutdoofAnr ntall.1tion kits to PermitenhAncet b) Ithe tolowing I catuWc- of rnub- ipphi-mum~ Ahcrc the hctrik nmubt bx pLA4.rdtary healr-- vuubdi of thr t~icicd -,pA;.v

i Is i) ctlctor hoods of gnlbý to Jumet Um 49t) %ejdkr inj urumzois rci~ismz tv

64t5.hjr a~ t5i i required i n thow inm.!Ltron-, diinrun~ib drtcnoration in cxtcnor 1mtAts-in whi%.h Jw I%' trL not u.tcd I.ittion

12 Long ~k-on 'rumn thriv~nu-tat pvr- 68 STORAGEniuting bcest Iixtiaon I if .ontrof ~us

Storigc fccquderincnt% ltu nuLirin hc~tmraii (opin~t ~ontrul pincl, ths!a ..int*.:f d .t the ý-amvn. those foriilt aatrN =.; '.0fdji

ijcxtcd icitmutt Ih. L4t PtUnistit4g iumcm I ht: ainna rnuýt nicet thr requirement%!MtjilLitktvn whe~re tx--t lot opcritor 'orv oit RVI k tot Ntorigr Without darnugc 3'

xintenr. tempcr~atures tron; - W; tv IuA"'anid lot -stati,. rxPQ~unc IQ -c s~ll t4ilou

414 Mufiptrap'tt-o operAhilit) prov idc.' raln. ~and Miowing sand and tdust writhout;ýpabhI)t of onforinung to %.ontiguration of undue d nrorition or c)L~ixi-c dcanup andthe .avajabe -,pace startup 1mwi

REFERENCES

I AMCR -01-b. LogX;.sm ko'rumsibidairi 4; %.IIL-H-I I P;I 11), I1i'atcr Siv, ifun1uIzi-1 s.,a~wn1 Ptn fi 1ns itmnrnaI ( minrld -nd It tgh Bl'vt-t 0t /of#$ Btu hr I S kmtRefriger~aton I quip nuss: 4 ApnlI jI4iS Miobhit- huupmcnt ( ommand. F~or

Bdo.Va 14 1b.L. I QtV2.Proposed Mthtirn Standaid. I1ca~re

hicufli, ( wnpavrnrnt Ileatre ( oolant b MIL-H-5'22O4I.Ikatert ýp.A lunut1Ifnjne. Heaters 5pat.e 7crh?,at.; IDatfa With Bhtswc? I' #'f,' Buti~hr L. S Arm)and ("hacfenucs t S Arm-~, Mohdmt oat -upmn onn -iEquirment Ccommand. Fort Hcboir. % a .heloir. % 3. 13 Dc'. 1,461

() June 196h

3. %tIL-STD-1i0-l. F n~irrarenrai Trit ifeh- %1L-HF52230A. Ikaicr Dut; ipx Awl-,.d 15 June 19'tY. Notk.-.. 20 0i_ 11169 $! Buh S zn ~oit

Equipapcrt (om-mrand. i-ort Bevoir Va.4. -MIL-H-) 104WJ . ii.-verDur I t* -r A Purt 1 De4. I'46

6bir, tGavflane 2 *'s' BIa~ tu hr.Arm) Njtick 1.Al~atones.. Natick. %1a~s . AR~ '7601. RricarthIkdp'iz ti

27Jul) 1W~ Arnmaendmetit-1. 21 Mtarch and I vtduatum or; Itatmd !or I ittfr(PnI 966 (hntwil ( lmd.;ao' 5 Ma'. 1.9


CHAPTER 7

METHODS OF MINIMIZING COOLING AND HEATING LOADS

7-1 INSULATION 7-2 REDUICTION OF SOLAR LOAD

Increasng the insulation otf .1 trb.urc L'. 7-2.1 GENERALonc -Aa ot reducing environlmental .ontrlU~louds. B~) rnclu-ing the rtel of heat tnianirri Soiar ridthtion irt~iolcm on itic vcternalthrough the eclosa~ng surfaces. both he-ating o sue' at truCturc ma% hase ia4e4nd c.ooling loads are retlumxd Fo innrn n eattanmuno tiug hcffectiiecncss. insulation rrust be applied mi Al ifurc nllttrnmso hog hecmenor boundaines of the virui.turc ~ a~ I hr totAl inidcrit radiation is partt%root. and floor An idditiorul Ivrnetit of retleci:d. P.Irtl% tbsorbcd. ind parth trans-

tn,~ao t5 tha it %;i a fuctonntted In gcncr-a!n~eabsorbt-r it prperil) selected tnd in-

"taled. il

A typicAl !ihelter wall has a doublt.-%alkd %~here p is the rellte-titiv of the surface. a thesandwich cornfiguriation Lonswsing ot alumi- attsOpt~s Iit o1 the mnatcrial and 7 1!S rtrn-

nuni skins with a plastic foam filler lo misiet H ¶Alues ot triese quantitiesý sic-re'duce thermal con~uctanse where traminen pniJ or, the anfgie of inLident.. of Iffc ammembers pros-i-de a heat path bettveen inner lion. an~d the t~pc of mnatenal and its ths.k-and outer sktns. the framing membcrs, ma) N-be~ For --andard olv-c drab pavu.t thlscparated fromi the !shcller t.ki b) swctons ot domirntn faitur 15. the absorpt~sn4l %hikh L,plywood. T'he disruption of thse thermal pathi spprnxirrjteI% 41 ,: Potm fear di wube-sirengthby the plywood sections help-. to prcesent giass it normal iiwdnt-Wem, the salue s cf thelo-,ahied condensaton* a, well as to lower three lactors are the tof'o~infthe os-erall heat transfer ratc A tsp:i..al oserallcot-fficicnt of heat transfer for this type of CR iI

construction is 0.35 Btu thr-ft-2 Fi. 1heVAlUC of this Coefficient can be kept In% b)reducing wall discotntu~ihte, and opersingsand h)~ minimizing the numlier of feed- lf-M a bronie. graý. of green hcat-absorbingthrough connections such as -acks onl entrs glass vi1 I -- in th-cknevs the '-aluc ot r v±.panels. pound tugs. fuel lincs, and drain lines. redu%.cd to aboxut is4t

For usc in mobide vulitaty equipment Rz ! mesag~J4,,uto the prop-msulation must kv resistant 1o0 wc 2r- serk- o w4-f radiation it, w-Ase1Cn#1m dri-vibirAtln. And it must be nonhyposcopk. tnbutton. the etf-ect of the eanth' atinos-Although the use of foamed plastic insulating Ohtte. the distinutin tvtween direct soLarma~tenaJ.; with closed~t ccdU$ reduces the mlots- radiatio. and diffuse A%~ radiation. the daihtuea absoutpvaorsi terrins tap of n sutponem and scasonal %ariations of solar radiation. and

sealng ut apor reain a mjm robem, the rclatiofi to Frogpaphilal location The

-1* o" ~gft oewam 0( ywad kep t rethods fmq etimating the effect of solarWRONI ofi owig immrlaw aof desoo pow~ of *e ration on heating: and cooling loads xre

k"Wb~ presente:d in Rets I and A dtw-ussion of


~&ii~ wubpuiaw appeaucmto uiace. Trin is ncariy 3 u fIte 0VeiaU twatmiiay qpiFsew Pais in Ref. aio to trawser coefficlent for a typical bhtlher. "thrtR m of heat Mrangser thro&4i window reasAltboah the jeugmr of ensronmental can be reduced by doubl~elaimwn but OU Is

control systems must poI& adequate sdeldom practcal in transportblk eqwpfent.capacity to handle the worst olar loads Funhermore, faulty doubk-Ani. whzhanticipated. the uer of the equpment can don -jot produce a real dcad air space. maysomnetims take steps that will reduce the encourage fonin and the growth of fungi.solar loAd and pernut more efficient opera-tion. Unl-u other restnctions prc•vent it. the Except where s.ca-i upphcations may rt-strutr• itself can be orentcd to m n.muze quire windows. ;: -. best to ehimnate them.the solar load. For example. the structure can Windows do not takc the plac, of artificialbe orientcd so that the w&At radiation tails lighting which must bo ptOvidcd anyway forpredominanrt) on a short end wall instead of iaght operation. Furthermore, windowsa-&-W. Ud W-.1.u weud- have to be blatckd out under Combat

Some of the methodb desnbcd in theparagraphs which follow. for reducing sola 7-2-3 SHADINGheating Io.ds in the field. mni) be unnec-ssar.if the environmental control equipment hjý [he contribution ol solar radutwn to,Adequate capacit%. However. there Are occa- cooling loads mn) be reduced subsh-tatall) b)smoni when the coohng .apacit) na. be the usc ot shading devices to exclude the sun'striadquate or marginal, and a knulcdgLe ofemergent4 methods of redwanu g solar heatingloads can be put to use*. Furthermore. r+on it Ylrioms can be shaded internall) withthe cooling capacity is adequat. it is -ell to roller shade. curtains, or blinds. ExtcrWlltake advantage of convenient methods of windows can be shaded with awaainp, oter-reducing the lo;d on the envuronnrenial •.on- hangs. and othr- pro%,c or.. Lousered suntrol equipment. screens are also avedable for usc extermal to

windou suwraces. their advantages .,3-nmparcd

7-2.2 REDUCTION OF WINDOW AREA to internal sceer- ame descnbek in Ref 5Most of thesc do-ics are umal•) rat practhal

Window areas hate high heat Itanster .oet- fir nuhtars usc For, shelter use. an externalficzeni' COflfl3t!d to tlý ea of a~ typtcal widwsu:~har-d 2--,!h- tcr Cý It--shelter wall. Therefore. it I, dcsiwalc to w-%ndow makes a pracal shadmtr device.nurumnze wimdou areas. omitting them alto- When w.pported open. it wot-i iEc as angether if possmble Houev;r this i% not to awn.ig, and it 6could he clujwd di~ng tr-•rs-deny tht fact that properl) oriented windows port. P-e shuner cod also serve a. aon a bright jsunny daý iman .admr enough Nackout curtain. Lateral projection. are -solar radiation to iin-f i.at a room quired for shadirV when the altilude angl, ofwithout resortng to heating equipment the st n is %o s•all !hat overhangs and awnings

are incapable of shading a window. It is rotThe overall coefficlent of heat tsnsngssion $wc.tia•W to sbadc aindows from diffusc

for an uncoated single glass as approximnatc) 4k) rad-ation a"d radmiin•, from the .ur-I Btu,(hr-ft - F) assunmin stl air on the rodinp,inner surface and a ".5-mph •m-ar at the outer

Shading aiA. mam be a•ppe to entirestructitet Fx -- ilustratei; the tae of

S- • __ shad•i•,ng t, reduce soar bheting of systemsAnCO opda"of *a VMS to P" m roofs u*tc

AdoA SU ta*90 %bM sWt - s 0 Under no codiatbrA sould the mniement ofsoi on" te vdw s to Agc a CeaboZas

V"CAfwtl ov'XO -SOL Aar CC¶-Sari to reinoie ?be hemt of corn'-

7-Z


AMCP 706-12!0

out, a reduction in the cooling load due tosoklr radiation can be obtained by increasingthe rcflcctivity of exterior surfaces.

An indication of the possible inipzoev entcan be gaged by noting that the absorptivityfor solar radiation of standard olive drab paintexceeds 0.9, while the absorptivity of a glossywhite can be as low as t0. . In arctic regions.where white paint does not interfere withcaniouflage requireiaents, its benelt resultsfront the fact that its loa clilissivity decrcascsheat losses from the structuic.

'Ihe U. S. Armny ('oaunlg anid L 'liellni.dJ

Figure 7-1. Example of the Use of Shading Labo.ratory. Aberdeen Proving around. Ma: -

to Reduce Solar Heating of -brtr.AedePovnGou .Ma%-to Redu diSonear oland, has developed solar heat reflectingAir C'ondirioners (SIIR) coatings* ol low %isibility. wiiich c.anl

be used whelc the high ,isibility ot whitepaint is objectionable. L(,w encrg, il.soiptio.

pression be interrupted or obsiructcd. Note while retaining a dark camnoullagvc olor istha. an air space for ventilation must be achieved by ha.nv rellcctancc in the mlrarcdprovided between tile item being shaded and region of the spectrum. These coatings ha'.cthe canopy if a significant reduction in heat i, rellectances of about 65'; lot inlrared radia-to be obtained by shading. tion iii t11e range 0.7-2.0 hincrons. SHP. paints

have been shown to be vcry cqectis c. haviiijg

Shading may be achieved through the produced temperature rcducttons of 1i0' tojudicious location and orientation of the 20`F when used instead of standard paints,

structure. For example, the orientation can le Olive drab has been the lai,, of nosN o (1Ie0.

chosen so that the walls inost susceptible to SIMK paints prodited, biut g !;)S ills and

solar radiation such as windowed walls, walls even near tlac', have bec; dh% !d..co. Aii

with environmental control units mounted in evaluation of solar hi.a reecting coatins is

them, walls with air intakes, etc. are on given in Ret. 0.shaded sides. Furthermore. t"-% cotirn, struc-ture can oc~casionally be sh,,led by proper The I alar ran re it cd thrilocation with respect to other structures and window areas can be reductd 1w a inhllef-

ucI oihaly available reflective fhlih'i It .onsists of )1natural objects such as frees. 1with ;1 4;J)ipor v:f

backini, of alumninum, oh smi. diran',pti:cn.,Wall-mounted cooling units for cflicient (one wa'. looking oui ; thit I ii c iii. ',s

operation should bc located to receive a R0041.

minimum oif solar radiation.7-3 INDEPENDENT VENTILATION OF

HEAT-RELEASING EQUIPMENT7-2.4 INC \zAý.,•4-4 fiEFLECTIVITY OF

EXTERIOR SURFACES If heat-releasing equitpment can bc isola.tvd1

Most exterior sulrf'aces of tiiltary equip- *()rc StIR paint, the .haiaoteriqts of uhh cr. ;a, d. ,.li () MILl.- 46r)096, i% availohhc in ,r4 . lln L;,I .r¶ 41 t'

ment have low rellcctivity. and, unfor- ileteral Stotk MNmbeg ( S.Ni 11Ii Ul4 4O11 , A.n,4i,l'

tunately, it is uisually not practicable to paint ki, iik'ril-d 1) MI1I . -46117I. ind hA 1 , k Irfl-- Int.11AC MI 0' a iit Ci&Md It) MI I 4 -461 iincrease ile reflectivity significantly, ow- +"stolminr c.lat Ocnroul filhn. n,anuf;,ilird I, i'. "VM

ever, when other restrictionq (IO not rule it 4-.. 3M r'nief. St. Paul. M.,,rw;la


It 11my be ponwbi to rceuu*. the ouhng load 74 RECIRCULATION OF AIR FROMbý -ntriatt~ngi thc equipincrit independent.1% HEAT-RELEASING EOUIPMEN7of the reit of the cricot~urc betrng .ontrolle'I-or CXAMPIC. thu, .tau be done with clcctro.ni,. tihe piding p~rgraph hias 4,iun ho"equipment which rquiC renilation, but 1Xpalite %Centilition of heat-releaung equip-

w-ichcn tolcrite temperatures higher than mnet i.n ilwxc the wooiing load The pur-the staximurn tepratures allf.,Able in per posc of this paraigaph t5 to show ho'u one L.An

sonnsel areas or other parts ot the uonfrollcd t.Ae ad'.antage of heat-~rcicasng equiipment to*pac Also. therte ITXwy be ircurnlstimtcs in ridu,.e the heating loid unde-r o~ld wcatherwhir~h the tcmemctture o! the outtide wit, unisostoo viigki for the personnel Areas but 410-A

enought for %cmilAtion of the clc,.tronj. rquip- Iv rcdu.,c the hcatin.; load it o ictnc3ar)ment A zcpar;.st isent-lating -systcm %.culd IV vaz Al vr pal.1 the licit gen ratcd 11then khnng in outs.idc &-,f pLass- it through the itfl e aUPsaanr it to e I.o nditioned spate Inclcctruni, eouipmcrnt and ciiu~st it t) hc 'Surn .4ses I, rný "uflin.. to dactisatc 3n%outside San;.. the tempcr-tures in aLI part,, v! ,%)trrrt *-= !,g br paate -crntflation of thesuc~h 4n Isolated N)%teni vauld N- higher than. tq~apirint Junng Ai.rm %cathct opemrtionthoe mn the personn0.-ox.,upicd spaic. greater, tt,.As. the heitit n, uon~c~c. tti pcrsonnet NpjicesrlcAsc~sncss would be aý,hicsed b) risulawin D% radlition And lict .on%'L.tiol HIo~einr ao1 thte s~stem It IN uwsu~ll) not pra~.ti,.Abk to this pro~cjurc allouws thc temnperature in sorre.sppl) ansulainon to ele U!T. IwPffWCitl par!Ls ot tbe cquipmr-nt to rise too high it *dilcabinets. but i.omnponcnts u~h it, du~tw~ork kbe nec stcm to nu.kc prosmaoots lto air troinAnd 'in housing ~an be ins~ulated (it ýour's the perwi~onel spa,.e to be, anurlated throughAn) leakage at air used to sent,.atc the the equipnment and returned to the personnelelestrona. equpment into the -,nlspa,.~ -pa~x lhese< ptt.;edurrN arc not praýti-,3ti.must be asoaded tAppendux 1) of Ret -l .o ur'sc. it the htei-e.csing .Nupmnicu Ask)dewribes a -sýstcm tor us~ng outside air to gesOtt unpkc4Nstn ovij'I' tom. gait-, ortcoot instrunent racks. Iot:~zc undcstirbic saph r', Thuis. ,or e.%amnple

-nt mis bePow.-Ik 1- rC'TU;1itC .iIt trarou

Separate 6.entilationa o hcat-releAsing ci~rn wr umnitr,%htn~ hoo

wnent is not pra,:tikabic it protection ±galn'4 h o-pr. 5w;ui

chemai.al anJ hso~op-_al agernts I, reýquiredSo only. is it usualt impossibit ti. wit uon-, ~an h ehnu e.:aei nsustems wo that outsaIde air .ould not kal, Into %ol ~ noa.an n ue tpac

persnr~ sptes ~u Lotano~a~or atthe av "Iam-ilbut~on Air sJhould b-- remosct! fromneupmesnr-lst~rs ontamiruuora iC th rind returned to the personndc spa,.e without

equiriwn vtý 1- un-cp~hlcgencrating undesirabl%. high %clocitives or An%tcndrzLA- tWaird stratu.6ationa

The techniqu-. of isoiition .an bc ipplicialso to other ofetsa efivronawmiial in. Mh- PJ tht pr-:cedirq parzjraph shoA'trot soda as :he eAtnrol ot hurmi i--, dust triat, to ts3kz lull advantacc Mf possible rdu.-and odors S'paratc scntdation of elquipment Tlon,- al cravaonicninai ronti.q it-ads heaivw-hr-h excmiesvl) grnerates water ,apor. dust re csn quiprmnt mnust K- -ctxlawe xithor odor, W.3) simplafý the solution of the cui;!vdc anr during %4rm wcatlict opcrationGverall envxrorintcnUI ,ontrol problem [-(ar and Aith inside sit during 4:old wcaliherexample. %ev srale ýi-,nttol atpotopo.csn oprtr8 1-i. trates. so. h a SV'teni

cQuipment. w-hich releasei. *apor% At in :s.sTedesam should pernit e-as% omemion, 4 v ratc. reduces thc dchunrudifiu.atton !oad from one inode ot opcewr~oa ito the other Thethat woulf ive cxperwni~ed if the Naporsm %*ere .onfigurtion In Ft#g. -. *-hw arm airreleased direct i) Into Pv"nr'el-o-..upICJ being rClICAed Into thC ,-ontr4LAlej Sp&,ce at a

spak ciýrelatoeh1 high clesatwin 41111oiigh it is pme

7-'


AMCP 70&?20

A Qa

00

I LJ',

+A w~-_j

i(N

uI'


AMCP 706120

ferable to r.-Icasc warm air at a low elevation, of how often tile bypass system vould be

restrictions imposed by other cfonditions-- used and what power savings would be real-such as available space-imay sometimes pre- ized. Another consderation is the Lonmparisonvent it. (o installation costs, with and without the

bypa,.s. Space is another factor to be con-7-5 VENTILATION INDEPENDENT OF EN- sidered. In ;: densely loaded v~ia or sholter it

VIRONMENTAL CONTROL SYSTEM* may not be possible to provide spacc for a

byj. ,sb, no matter how small the ý;djitionalWhen a niobile system Is ti, I a large space might be.

fraction of th4 time under conditions whichrequire ventilation only without temperatureor hunidiiy control-there may be an ad- 7-6 EiFFICIENT LIGHTING SYSTEMvantage in designing the system so that tiheenvironmental control unit is bypassed when Thee heat generated by an inielicvient light-it is nut needed. For a given ventilation rate, ing system places an added burden on thethe flow resistance through a bypass system air-cooling system, ioweve. it is not alwayswou•d be less than that througI tile environ- possible tu choose hile umost efficient lightingmental control unit; therefore, les.s power system because of othgm Iactors that Joust bewould be required. considered. Although lluorcsciii lamps liaNo

tile advantages of' high himmlminou. , ticnv."I lie nature of the bypass systeci will low hica' generation rate. and J,',iglt', tl -

depend on the application. If the environ- produce objectionailc radlo-frctucemw intr-mental control uniz feeds into an air distrib- itence unless Cquil)ped with ,Il)cLi.ntieduting system, the bypass may be designed to shielding. hIcanCes'cent laml,, are ICes tCt'itCIe

feed into the same system. For I small and have a shorter lilt under normal operatingenclosure, it mnay suffice to proviuc a wall fan conditio,,s tut they have flhe ad\,.ntaz;gs• thatfor use when the environmental control unit th4y are njot an inherent source of radio-is not needed. It collective protection is frequency interf-rence and do not producerecui.-tt, the bypass should be designed .,, visible flicker. The acceptabiilty of incandes-that it,/et air pas.ses through the collective cent lamps is incrcased by proper lotJcrprotection filter unit. design. Louvers in a lamps).adc or houu.ing '.n

enlhance natural convec.t:un. aiding the dUs-

The decision to inatall a bypass ventilating sipatioi, of heat and ui :.ig ! Ic .s objcIiont-

system depends on the evaluation of several able for one to bhe ch ] io an incand"scent

factors. One important factor is an cs!imate lamp.

REFERENCES

1. J. L. ihrelktcld. Thernmal Environmental 3. R. L. Franseen. (',,dtin and Ih'at'ng L,'',,iUingineering, lPrcntice-hfall. Inc.. Engle- ( ah dai'o'ts fl/p t:ltritim pir ttal ((flrtlwood (lif's, N. J., 19(2. I:pqilm-'nt1 ,pp/h £ion., ".S. Ar m

1'. 1lgIneTR t'eeari hi and 3 )11 1)1lpnmnltl2. ASIfRA'. Iiandl,,oA o/ i-,imdameniaLs Laboralotjme. Vort lie] %ior, Va.. I0

Amer. Soc. of lIcatin'., Refrigera'ing and September 10115.Air-Conditioning Engineers. lnt.. New

York. N.Y.. 196/. 4. U3,S. Aim), m lest & I'valualtiun t ( onmandA i)((ial Stir4, dI A( wirl tit Iltattw and•,

*In a ,cakt s•nw . iu;z. 'itgestion of th..t raralpaih doet n't (6''lirg ,5'.siC??•i of I'Um' 41, ,m 'l%/,lit r-alter comling pr healing loads, Nit it was considerc, woriM,)h' mention i•bellal II st a &ay of reducing power ' 'Stequkcment.. Armiy .lectronic Proving (. ,,tdml. !:ort

7-6


5 .W F~nn-A "Ifow Lw.nvrv~d SunScmcem Cut Cooaing, tlesing Lowa-,*Heating Piping and An~ Conditioning 7- kadio 'oi-r. of Ant.- -tuei Repl~ri Llec

40ý 1 .,). R~-,-o % r.; rnnft Trt . vt tto'.. &i 4 Me--ukni4~alCov y Ne rations AlTY-M'TE-L, Ratho

. .F. Pickett SW-v fleat Refl~eaij'g (.oa) - Corp. of Am.. Artrospact Sy~lvn l~ihwo ftpcr 690:86. SOCie~y Of AUtOlf-11- Burlington, Maii. A~D-476 2j4 i


CRITERIA FOR SELFCt-ION OF ENVIRONMENTAL CONTROL UNITS

8-1 INTRO CTI (4) .f•bilit> (A ermbly and Dstembly).c fThe tune required to assemble Al components

SThe factors which goern the selection of of a system and to put them into operation atenIwronmental control units are discussed in a given location should be as short as possible.this clhpter. The primary considerations arm Similarly. it should take as little time as.the heating and cooling capacitics, anm the air possible to disassemble a system. and preparefle-w reuir•ncents. Followi•kg a tentativr it for transportation. This characteristic en-selection on th!: basis of these requirenments. cmpasses the posble =d-••i - of t;ie num-other tactors to be considered include spatial bet of system ý.omponer .s that require asem-and stnctoral limitations, power and other bly. the sunplification of ca?'le connectionselectrical requirements. and tramport con- and ductwork that must be set up in the field.sideritions. and the acessibility of auxiliar elements

such as power sources.

The general oljc,!ivcs that guide the choice The final desig should te arrived at b)of !wnvronmental ;ontrol units and the design considei of altemative components andof the environmental control system include: coardtrations, and a selection of the aost

effective combination in view of the desiredsh(1) Layoui Compactness. The equipment clh, acrctisucs. Undier some operational sitiuashould require as fittl space polible, and tioets ithe various environmental requirementstee •rrangcefnt should facilitate efficient for pesonmnel et'id equipment in a given

dprformance of the mission. Rksp a preides appocation may not be mutually compatible.i• gudance for meeting wo) teqtCC - The designer must then make adjustmepts1Uferts. whk* produce the mos! effective system

S• within the limitations.t!1!) Openitional Hiexi~ior. It is desirable

th that the system be adaptable to a variety of 8-2 PERFORMANCE REOIWEMENTSmissions if this capability can be achievedwithout sacricin the prinmay nmion• Th"is "I4 ETERIMINATION OF REW IRE-characteristic aiso includes the capiity- of MENperforming a given Inision with a Variety ofequipment configurations. Therefore. opera- The fit sep i• selecting m-om.,.altional flexibility may involve the ;e of control equipment is to cakl-ate the enmiron-different parts of a system for different mental c requwemnts. Then one canmissions. ai well as intcChan batrty of conduct a search of existing military and. ifcomponents. iecun,, commer-W units which meet the

-- Te oftdedn mquirernents. It is beit to investorte(3~ ivnso~ahity.me ese o tras seera design concepts m4d to choose the onew

portation by truck of tractor smi he as most effective for the applicatn. The e-al'a-reat as possible, and it is also desirable that tion oc ahtmt-we cis may nequwe a tet

the system be adaptable to ther modes of wuom to dernkiwrate which of the Con-tramponatfsm by air. ram. ship. cepts ik best suited to the requk, ewnts. A


t Ik 4 ý_ tt kj- t.!k n

n.i' Pit~ rn C Re t '~~~~~~

udrthe-w huvr-.,r _Asiim

N -! CA pni C. SýUtlines the proclaUOutflr ,ý U 1014UI One$. 10 ui4c thrdus.. for determni~ngt cnviruri~ncntal iontrfvl siandar.J d&z-pturpu trvv nmrn4) .~ontrcAtrqtutreinenls. and par. ( -3. A~ppendins (. pve~i Uniht, iflks- jtNA c jquide ckaltun an br

al exmle'f Jx, condition.:.- w~otion gieg tin ~ ~ in~ urnit W4m.zt prow~tcs cmoling onljy. Another type v! mtua-

Although Army regulalbuns specily Wh1ajp- tier zxt lhc~ the "tavditrd fl0Jle1i

ter I1) the trt~i mients ',o be met by cnvtron- co')ftiA U!--, that u fei rh i.oalig '-Cqatmental control systetnB. it is nocewsry also to UineXt J`At" M4iul of ffuif'illiny the hedtmag

tAke into account any ~vilrequiremrents Mqanwta extiefftY J(o1A ctrYJai! :=-

that might bee imosed by the applicatton. Fo blent tempeidturm5 in such ci~ses it may byC-iiisipk. the activities which take place irth necesaryý to supplIy a imppleawnntary byvater.controlled space may demand more flzi 0ne should also Qconsidcr. howalkr-r whetheinormal akertnms from the ape;.dtbors. and the the iow heating CZapCity COUld bz AdeqUilelyrate of loss of alertness wher. exposed io' the cotflpet15rd by outfitwi2i e ks-sonel withliniroling envirnmýntal codtos al~db arctic cdothinf. Ths ncinaurt wouwd b- t;,-

rmy replu ions may be U02Ccep~tabl high. cpak&nl t m~mew~hraAnother exiample is provided by activities f~t~ il~EhLo~ itju bC _SSUtrc S~

reqturmng a ipeCia degme of clcaalirvs3 which peronnel to pvrform their fask!1 whil wear-*vuld be inciumpatibk with anerronn ing arctic gear, Anathcr possibilfty. i0 it isconductive to high pers~gratuon rates, Uinder established that a mlpplemcntan. hwatet issuch conditions. one should design not merely needed diz!ng a flarq fraction oi Me operat-for tolerability, but for maintenance of the ir.F tiiw. is to chuoos a heater capable of

more ideal conditionts needed for the required meeting the entire hCatL'g requirement And

level of perfor~nmanee ormitting use of the heater in the coofing unit.

64.2 COMSWED HEATING AND COOL-ING UMTS VS SEPARATE UNITS S-23 NONSTANDARD UNItTS

In so"M colas it is preferable if heating andcook"n requirements can bc net with a single ft is Mhoably fetasibk to "Wct an en!fVirn-

C-vrmnntal control unit I %-isete -- intnti csmi wtrqmiremnts nthat re likeil tosepara systcIMs W~taaly complicates the de- be ncroitntered in mobile truunyiwvruncturessign of the air distribution system. It also by the use of exisaing em~iMcinment controlcomtpliates thte aulonwtic temperature con- equwpinen The *itiuition will improtec astWo system, 3dd (0 maintenace prOWleMs. mote of the units now be"n Punned or unukrtand increases the k*Mk sticspport buirden. The dem&pinent bec.omc as-Ait*.c floweert.cost of a unit which congbijse ha gM cases array he encountired in which the designcooling functions will probably be lower IThan comId be impri.wed substanxiiAll with a newthe cest of separate dcvices uidtabkc for the itcm: and there may also hN speetl cnviron-s;XW application. mental control problenis which cannot tic

solved acceptjbl% with any owti~ttt i~quir-mcni. in stie cmtm. it u. ne~-rccy to prepare

The xadatages of units embining heatinig speciflations for the cqwipavat nevded andand cooling &k not spply to al cireunstances to initiate Procurement in a o-Crdamce withhowemc. in some applicatkios. heating may establiMWe mmittary ptocedum3'.


3 E'tC1IK~CAL ItM ýrA FtOW "n~~,az ~ c i

8-3.1 FOWEA.MWPtY OHARACTERISr PVswn frNUAwITRrft s&Vald -Atc MKnTics tan Ad~igCt tht Pf)Sfltf po*t! awl

would ther. LAut mfiitC ex4cens power "PApLnnronmratdmu w.ntrol units of each capac- bility, This -sonudcntaon is espmwluUy inpor-

ity rTatng arc umsally Araihablc in snodch, -nut toto ne*4b developed structume %+*Ahhaving diffesvint electrica chancterastics. Mr. gabty pow In appliaUo1n.* AnM openMost of the .-tandard units are designed for tjonul tdenin~s after thecy are used ui Gieldoperation 4t 2081 V. although some smatle opmtfliol.units arm ivailablc in i05- models. 1 hepower ficquenwcis are either §0-6Hz (I or 3 Air conditioncrs create a large 143U)$phases) or 4CQ-fit 03 phrýC. Most conbos- pow.-r fac-tor that adds significantly to theion beatenr have fanis wihich opcentc on durtct load of the psinmay power se,-zz. Mflstotgh

Current, at 24 V. the rower factor car, be Liwcrased by die use-oft compensaing capaciters, these wofld In-

(outpre.J ith b0-llz power sourcms clewt tthe- seveity ortarc transients.AfX-dla sowrc,!.- hsweý the advAnxtrrs of preater

unmphcitt: and higher power4o-wýieit atjm6. *3.3 ELECTAICAL INTERFERENCEThafre.--m theze hos beeni a trend toward thedceieoprnenr and use of 400-14z equipmnent It is import-ant to 'Wtcrnune whether theand power sources for trainsorable apptica- environmenotal cotitrol units under ý.on~udcra-tions. When a 400-dz primary source is use4, tioua Mrc liely to 4create transiernts of utf-fi-it would be pvfer2'Ac if all of the AC CrUt severity to interfere with electrorutelectrical eqip~menit could be operated direct- appuatus operating fromt the bamnteve-,ý--lY from ýbc soa'rc. Howner.f iflt is meessy suppy. Chapter 4 and 6 discuss the featuresto use somne devices t.at Operate from 604k incovporated ivio standard military units to5.OrcnCCS ! W)1ysfrt a'tatt rfrequency convestns pvewr$d AeXsakftfftw "?c ' srciiircan be Insalld to convert the 400-Hz priý- the requicmenat; that must be met by mifll-rnaty power to 604kz primary power (A fly eqipment with resent to the enuWonmome cowfrete discumion of the relatve i, and mceptiblity to. electromnagneticadvart ge of different power sources may be intafe -cuemfound in Ref. 5.)

U4HWUCAL UUITATWWS*32 FOWER RATING

The femaity- Of mnowatua the enViron.Power comideratim ensa an importat atm" cactn tqi sijlmnt in fth stflituft

aspect Of selection criteria, and they mway arid attsct4 powe cables, control cwcuitr).sometimes be the dec~idig fator for the fuel lines, and ductwork provide additionalchoice of environmental control sunts. fUs criteria for the Selectioni of munts-would be- the cm, for example, if then werlittle difference 'in the heating 9!d ooin A review of Chapter 2' sill ad wn sdiecungpeffomance of the differet units une the type of instaflation =---a seistl for theconskidratkon and they dIffereW little in other application. The intornntion in Chapter 9 winlrespects also except thet 01tt of them it- also help an the evaluation of different mstat-quired substantiuy less power than the laton cccl lgwuationsothers Chloice of the unit with low powerrequirements might wake it possibe to use asmallr prbimary Power uw$ for the entre PAnnt' that need to be considered include"system. If the difference in power tcqsn-:-"usents were not0 peat enough to prime: We 01 It Is space avalatle fee the unit!


Whwot nunt,-4ctmfanton akm %-hf th enMMOMAý-11MM4 MI- Af

43 1% the structure strung enougn to $up- ductdwork and tu -ttirr ¶1.hrw itctm, ThtPort the untf' repmte unit inuso itut4 Le Inpared for

ttansport. A tradIvr-nwunIA unit might not( 4) Is the unt comatible *nth t;=ai require tmudi .-tfot. but a Akid-rnounted unit

disributin# tystegn" requires that 4 transpor vehuck be avaiubbleand that prvi~siomm bc mnadc for loadzing the

S5) Will the controls be convempently acces- uhilt.

t si~cqThe TrdALte unPortarý ý t;1'(6) Can maintenance be performed satis- sideratioms. wompared to those discuwed ir.

factorly' preceding paragraphs- depends on the rn por-tamc of mobility in the geven application

(7) Will noise level of Mtdlat~lian interfere The nm.rc often transportation is exipected towithA OenUGM' take place. the greater urill be the imnportanc.e

of mobility con-idmtaions.34TRAWPOAATION MIWTATIM

$4.2 VIBRATIONW4. MOBLITY

One of thc major facr-ts t- Ne tonadcer'dflefore a rinsia selection is made, it is is vibration -both of the envaoonrnental con'-

eesayto consider how the Oint afrw-ts the tWo wuni *nd of the transporting vthicletroportatility of the sbuctim on which it is Compliancv with the %filitavy Specifications

uw.¶I~tq V Th-,Chaper 4 and 6 any be hefUJ ina mskia that the internal copn~emnts of tnviron-this fiA&W eaatiA~ou Weight. Ohm, Oad Pew ame" control units will withstand the vibra~-vbkos of lift af utl-dm deyics. are am", tknfiinduming forces of trilitary transport. Thethe facto"s which afleet # units thc-mselres are usually inst&Uid in a

structure with fixed attachments rather thanwith vibration-bsorbing connectioms. Hfow-

Fron the mobilty poin of view it would eme, shock-mounting can be employed inbe desirabl if the envrewsaenal MOWto cues where vibrations transmitted froin thesystem ntqiked nothk* more than routine environmnental cointrol unit to the struc-presy""Mok for trApost. Thi insiht Includ tine and thence to Other equip-Such tperati as shuiad" off Power. do*#i mieft -would be intolerable. Finally, it isfand lines Ao~wtadcvrn extelMA Omneesry to conside the capbabities of theWwmpoiwt. Such routin PqvpMaou winl tramproerin vhcle*. Excessive vibration am-suffie a*y for urits which paaft- erwnn Phtodes. capabl of causing damag to pipingIM0m-sad an the sbunctu. Mor time and and odhe pelts of the isSmiaoom may reulteffout we requ1e to pwuptr for trinspwt if' the milt is too !MWg for the -. rhicle.

1. VAS Army MEL StMM4 "-646. IMsWW (AI).646 611).Fwtcos Eqhoeoiq Des4 Soadod for 2. C. A. lIsbe Cerdkcti he fteela~ forWh~eekd Ve~kks (tespwal byr ft. IF. Chad- CowANg FkWi Smecrawr5. Vol It. Reportlet anW A. IL. HMONO. AbW4M ftw No, 3MO. Witon Systema. Inc.. Mose-

um e Qaud, MMyld SOptember l%6 Vaobs, Minnsot. September 1966.


4014~

Rt Irfrtrra~un I quigtnen'ni 4 Apni P'flMt ý.\I )4 Jfl~jJr*! nr

¶ Il (oiflhtflK~I~f S~sm~ 1. (lp 4 pef h"r t terJtI V,


CHWAPER 9

L INSTALLATION GUIDES

S9-1 INTRODUJCTION4 distnh-4ion Hlowevr. militapy .3ns and Largstru'rtm'e- do, require ductwork

The purpost of !his chapter is to providesoftw guidance for the uistallatumofi 0 rtnIV~of There arc casecs in wrhich the trsinmentalmvental ccntrol units. dmtiwork. and other control requifeezncn can be met by a corn-auxiliary equipment *hvirneedd Sor of bination of fret dischirge and isae use offth informnation, such as the paragraphs on ducwork This situatb= mnay ariwc. for ex-

mowulndt design. applies primarily to air' amle if th peso~ are it n enough 1oIconditioners. but most o; it has general be venilaei ~piopy withoust ume of duct-applicability. It is assumed that theflrequisite wark. while thecre may t,- cqupipment cooling

requirements which can be met s,.orte rffi-sekicted, but in c-mms where one has a choicc ciently by ducting air 4iirectl) from the zirI bewee seera sutabe sstcis.thschater cortditioner to the equipment Iand exhaustinw

oimtallatiai-, ma tvl jin i the final- 61uecdty to the abrnosphere). in such casc!. the5scectiof between co pe~itivr systems. capacity of the unit must equal the total load.

Ina[to oO prah nte = -n v,-rpriat: ft-tion of the outlet &r~eis w-U tothe ouuipmrnent to be cooled.

the deuign and insta~ation of ductwork, ote 9-2.2 LOCATION Of EN VI RONMENiTAL.topics co'.erd inc-ludes airccuation and COTROL UNITSdistribution. CONIMIb, 300feY MdideMtOGM

mxitau*40 moYUwom Sil noise, 'rfrl One of the first things to be decided in

I eniwrontncrital control unit. Some of thiefYbt VWNUft4* f"1 a"IW tSO ir3 factors that muost be considered arc indicated

Pidwc, on work wamevmrtm in the paragraphs which fe-How. It w.4il bequimmnsm, flaMntelowte IOMOP5. Wnd heipful to review (7hapter 2. which dewcribce'athe topics piftnent to A~a~tioII5 in UnW air condifioner installations. It *ill &Ls.o tRuY a&ctwres Manuf&turess of environ- Wru to co"WHl other Varapaphs kit Ithixmnsital ct;nftroI umib tant Lmvs inclde motal- chp~et i9 which Pic factor% -nen~kinct) bclo%lation date in theis piubhicatiovi. ujeb as Ref. wek eil

9- OMRAI. AARANCHEMEW OF 00V4- ( I) Air ("tz~'alon. The way in wfitch tht4VINONMKf4AL OTROM SYTEM factot affcts* the location of the environ-

ment, ai control unit dcpends mainly on9-2.1 CHnIC* RK U E ft WE S whethtt the conditiontd &i is to bc deliterrd

CHN AND DUT 5YWVE throuvt free dfachatWe from the unit orthsuu-i a duct 5ystew. When using the

*Mo military sheftess and other Sna"l frtt-d*sme method. t%-, unit must be kmmob*e atrutue wre srafl enugh M that cate4 so that the anr will circulate wherelittl. if any. ductift is ncedem; for prome W require without exposing PC'-.onnel We~i


Veloctitei4iA-.t -i t'v fcvý 1I.Ep -i . 'AU ~i ciklt ltth tjaA., C111 Etic une ~"It-mino aAn "dki.1twc' qlkugfd Mit CeVdC IMA~ I irt'. (.ci rb% I~dt"411 14, ikrv.rsnc 111

It-min Vdten i -&Kt ~tjn uuisd Ow unit 4"ln i. t j'~i 1'r1hrtkernw't.,tdartc-hiauy tX lvO%.SteJ in I fC~jioVI UnC%;X,.e'd rlp' ý'ia: ;at this jrlan~fCItK 14t thcV vvalt!'11curr,

Poution gotryted. b) tbC de-agri t the17: duo u .. v. 411 1.ý . ' Iitrt.tN a2t a 0V

wuk ~iA ht--: j.rrjngcmci;1i iiN %r ~ ill I igI B lclert thc .UrPp) an~ Vntter- tlhe pt-r'crn-

t2l C aripallbilittwi th L;;wriwi ' ti r acd .ue. t!h:ourg1i a :rtarated e.-lnje %lirPfA'qtap"i-ent Vtjf, shelter.$ aNt te ilunt vjipmcw~i~ rjAd. iti Ow ottowf and flow,ýystems Are ust~lý oiaderd wiih ýqwpirnwm. 'dI~ird ttiiaura 014o"; lintk III- rtur~i 01'thus Mrictring the location Vf the Clvfol Jtu~ts fit hj r744vilrit shown Ill Hy 1j!.(Imental contrvl wtuit 11t is htghhý dt.-Nrabic that I-, wzrtilat to thc onec lit Fit! r'I 3 x,ep-tthe environmental control enginlxtr pa.vrici that thC iiso &.1,f1 Uth11 'ýPiie JtXo% thepate in the design of the wotz-l .systtio w thit pci-lrted c.euth into Nep.±ralte v.iparinrentsenvironmiental control consaiderations will re- -,uprdsed bý indis~Jd,al Ju~vb Ifiip.5 1,; -uaajn-ceive due attention along with the futectional tee unflormi delie'j-, '~t NEIPPI. an1 1 tirequiremients of the equipment and the pet- rgm Nt ho)1 m~ Uig 11-10)i it. ~witbicsonrtcl operaing it. This is particularly true if when thz! spwc. to Vc onditioned ~s relhtzsvl%the equipment itself require temperature open Instvad --? hznng 6%z tdb equil-control (or any other tylx of envirowni.., men Ibc pcrfurtted ceiling 'ielpý :- diotriIh-control). !t m. usually necessary to trade-off tit%: (he s-uppl-. aui c~vnhi'and tht: niturAloptimum electronic equipment loc~.tion with ferident:) of tVIC o utt r-

dimate cvtM-oi cquip~mn eif Vuitmfl ts- support,. eirw.uatin 1hC a~rrangemenctt n-Ul

~*i I:P s a~i~a'~ otIc Uric in Fitg )- Ii b(3) Maintenance. The enrwiwonmental con- with the alr used to i.0ool Mfe 4C u31Ment riick'

Wr!4 unit should be tocated so that inainto:- chauslzti ditectlv to oi outside Puis i-flace. P&CAZtic - !h-' rmutine tasks. can be t'etter titan rc ligthe air when the tcempC;-performed as corvrtnientlya p ossible. *-rL. mue through the equipment racks is so

high that it vt,ý ýx-rcaw the reclired(4) Nonse (JontroL Occasionally it is pos- coyling capai, ty of the environricintai

sible to achieve a measure of noise control LMsimply by the judicious iocation of theenvironmental control unit. For examiple. onc Fig. I)- Lilt 9-1 s1,oii% typical heating andshould avvoid loc~ia the uzlit near an area jir-ourditioriin installations in .t wyni-trailer.where personnel will be worling the fadithc, the firsit with vettital heat ducts the sc-_ondthe unirt i5 fromi work arma. :1e- casict it will with borizontal heat ducts, Cooling airbe to reduce the noise to an 2C';Puwb level. w.pplicd through a prdo-rated cedting and

Vt)-tt *okiLg th- licit ducts

0.2.3 TYPICL SYSTM LAYOUTSW3 MOUNTiNC DESIGN

Fit. 9-1 illustrates rwe traik:-ype applica-tions of enviroumental contro systems. It. the 9-11 INES OF MOUNT INGwanuipiemnt of Fig 9-1 (A). ductwork is usedto bring cool air directly from the air condt- 9-3.1.1 INTRODUCTIONtiontr to equipment and work arma whichrequir coofing; air which has powed through lht- viri-us types, ot ctnironinental controltheequirment racks nixes with air in the unit Installations %%etc illustrateu an,# dits-

work ea.m and returns to th~e env-ironmental oiiwd ini (iapter _'In lths- parapaph. mount-control unit by way of at psmsg~way A tog and attachmncrt methoids ore covmdei in)

9.2


AMCP 706- 120i

(A)

I9-3


AMCP 70i 1L20

11,.

44:4- /

ir0 AN RM

-- '-4~i .4 .

•Figure .9- 1. Typical Air Di•.tribution Arrangements for Trailers (2 of 3)(Courtey of Ellis and Watts Co. I

9-4


AMCP 706-120

Fit,

- A- -/

i E/*

Figure 9- 1. Typical Air Distribution Arrangements for Trailers (3 of 3)(Courtesy of Ellhs and Warts Co.)

grua:ter detail. For convenience, the structure the shelter door. This type of mountingbeing controlled is often referred to as a provides free access to the unit for mainte--,helter; but it should be clear that most of the nance, and it frees wall space for other uses.information is applicable to other mobile 71,e door hinges must be properly designed tostruct .ures also, such as vans and trailers. provide adequate support for the additional

weight of the environmental control unit.9-3.1.2 THROUGH-THE-WAI.L MOUNTING otherwise, the door will eventually be dis-

torted. Objection~s to this type of installationFig. 9-4 illustrates a type of mounting are that it is cumbersome to open and close

sui'table for relativelý small, one-piece umts. the door, and the electrical power cable mayThe unit is held rJ'mly in place by a frame become fatigued by repeated bending.which surrounds the unit at the wall of theshelter and a bracket which supports the 9-3.1.3 EXTERIOR MOUNTINGexternal overhang. It is necessary to cut a holein the , all large enough for the entire unit to Exterior mounting is most commonly usedpass through. Condensate is removed by a in larger shelters, where the environmentaltube connected to one of the drain connec- control units may be heavy ard bulky. and ittions which, in iinits oi the compact family iý nonetheless desirable to transport them as(Table 3-1 ), are located on the front, back, an integral part of the sh.tr he-ai-rand sides. This type of mounting is also permissible width of vehicles for the variousshown in Fig, 7-1.' modes of transportation generally limnits ex-

terior installation of environmental equip-Fig. 9-5 shows a method of installation, merit to thle front or back of tile shelter. The

applicalble to small integral air-conditioning units also can be supported on a platformunits, in which the m,.aunting :s made through attached to the outside wall of the shelter.

9-5

1-I41


CII

IZVI

LLIr0L1 4 04


,Ci

I I

9-


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a -

N.' -�1, m.

a

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I'.-* 1'

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4-C- I

4 5

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94

I


AMCP 706-1ao

9-3.1.5 RETRACTABLE MOUNTS

""... A special type of through-the-wall mount-ing employs a telescoping rail support, asshown in Fig. 9-1 2, which permits the unit tobe retracted into tl~e shelter. The ck'arancebetween the unit and the shelter can be cloedby a 1]:xible canvas or rubber boot. If the

unit is connected to ductwork, , flexible orremovable section must be provided to icc-commodate the movement of the unit. Thisarrangement permits the sheltei users to movejj •the environmental control unit outside theshelter when in use, thus freeing usble spaceinside the shelter. When not in use, and whenin transit, the unit may be retracted into the.""helter and the opening covered by a door or

Figure 9-5. Door-mounted Environmental flap.Control Unit2

(Courtesy of Treno Colrn'r;,y) Another example of a retractable mountingis shown in Fig. 2-3.

Opvnings are cut in the shelter wall for supplyand return air connections as required. The 9-3.1.6 HEATER MOUNTINGtrailer nose installation as shown in themiddle photograph of Fig. 2-7 iN typical. The mounting of heaters in mobile struc-

turcs is usually quite simple. l1I most cases,Fig. 9-6 illustrates an exterior mounting, in the heating unit is mounted inside the struc-

which the frame is hinged, permitting the tuee, either resting on the floor or on aunits to be swung out 90 deg for servicing, convenient shelf. Several heater installations

were illustrated in Figs. 2-I and 2-2. Addi-'Fig. 9-7 illustrates the exterior mounting of- tional examples are given here in Figs. 9-13

a large air conditioner which is enclosed by a through 9-17. These show more clearly thedetachable frame. use of brackets to keep the units in place;

they also illustrate fuel, exhaust, and power9-3.1.4 INTERIOR.-EXTERIOR MOUNTING connections.

Environmental control units of multiple- 9-3.2 VIBRATION CONTROLunit de: ign can be mounted with the evapora-tor section inside the shelter and the con- It is e..timated that 99%,4of aH air condi-denser section outside the shelter. An tioners used in mobile military structures areadvantage of this arrangement is that only hird-mounted. Antivibration provisions with-relatively small holes need be cut mu the in the air conditioners reduce the intensity ofshelt,'r wall; holes are needed for the fresh air vibrations transmitted to the structure, soinlet and the refrigerant lines and power that there usually is no interference withcables. This type of mounting is illustrated in satisfactory operation of other apparatusFigs,. 9-X, 9-9, and 9-10. mounted in the structure. However. rubber

gasketing is frequently used because it is,evejal views ofan interior-cxterior mount- ccnvenient to apply and it does reduce

ing of a fiv, -section multiple unit are shown vibration to some e; tent.in Fig. 9-1 l(A, B, and C). Fig. 9-1I(A) als(;illustrates the floor mounting of a heater. In the case of through-the-wall mountings,

%9-


AMC~ (E--7

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ti8

(d)

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Qo

9-10


AMCP 706-120

t [

4

0

0

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9-I I


AMlCi .,00.120

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1

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.42

,9. .


AMCP 706.120

8- T ( Ul MI i " A' I PI

Figure 9-9.. Wall-mounted Heater and Air Conditioner in Shelter

(This pl)(Ptogjraph is for information only and should not be uosed as a criterion for thedesign of mniJlr Instalations,)

a ,Jearanct! bctween the outside enclosure of power cables are usually attached to the backthe Ciivironflental control unit and the hole of the unit with MIL-STD connectors. butthvout,!i which it passes helps to prevent the alternative connections are also available attransinis•ion of vibration to the shelter struc- the sides of the unit.

,ru. lhis is illustrated in Fig. 9-18. Tie unitis c'_ntered in the hole and bolted to the floor The control panel, which is mounted in theof the shelter or onto a platform provided for front of air-conditioning units. may be re-the purpose. The opening may be sealed, as moved for re-mote mounting. Control cableslhcwn, by use of an aluminum or steel angle assemblies are available for extending the'and nbl bcr gaiketing. When units are control circuits from the unit. If the controlHinounted on a frame attached to the shelter panel is removed foi renote rmounting, thewall, a vibration absorbing gasket should also opening should bc closed with a block-offbe used between the bottom of the unit and plate provided for the purpose. Also, thethe top of the frame, as indicated in Fig. 9-4. sensing bulb of the thermostat must be placed

in the return air stream.9-3.3 EXTERNAL CONNECTIONS

When making interior-exterior installations973.3.1 ELECTRICAL CONNECTIONS of units designed t(. be installed with the

evaporator section inside the shelter anu; theMilitary environmental control units are condenser section outside. power connection

provided with power cables or terminals between the two componenis is made withwhich can be conveniently connected to the MIL-STD connectors. This is illustrated inpower source. In the case of air conditioners, Figs. Q-8 aind 9-10. Fig. W-I, illustrates how

9- 1 3


r- 77*-O

d -

r ~ ~ -IMY .9 1 ' E t rG-utj9 f C n e s- S~ci n f , 0 g fl r t o d to e

ShwiU Poe Cable and -. get hi ~ o o ra h isf,7 - 7 7 -om i p O l o d sh ud n tb w g& rrjj ,O ,dalp of siia in7l~~n


AMCP 706-20

- Ir

u*1

41

ir In


'4 ii I*1�, (I j

Ag 4 '4¼

*1

(.�

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N

[I

.4 ,, 33

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Af

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9.1


twom

Qdi

S9-i8


9.3,3.2 COOMESATE MAIN

A condensale drfin tube should be con-nected between air-conditioring umts and theexterior of the shelter. A trap should beincluded next to the unit, as shown in Fig.9-20. If there is only one condensate dram.the connection should be made to at. If thereis more than one condensate drai as in thecase of verucal comnpact units, the connectionshould be made to at least three of the fourdrins provided.

Depending on the climatic conditions andthe size of the unit, the amount of condensatemay be considerable - measured at the rateof I O's of gallons per 24 hr of operation.

193.J3 FUEL AND EXHAUST CONNEC-

(I) Fuel Connections.Figure 9713 Heater Moune on Floor

of Sjutr Fuel tanks for combustion heaters should(This oo•paw for ifw-mtvov onay Ai be so located as to avoid loading the fuel

sA..cd nmt be Lwd as cririvion Apr U pump umce~safrly. The distance betweendnin o-O Iilrw iUI.*emJ the tank and the pump should be as short as

posible and the connection tube should be ofthe power cable can be pawed between the adequate diameter. In paricular, the tankcondenser fan and evaporator fan sections for should hot be too low with respect to the fuelthe type of installation shown in Fig. 9-Il. pump. If it is located above the heater. the

tank should have a top outlet, which shouldbe provided with an antisiphon detice. If twoheaters, each having its own fuel pump. are

In Ref. 4 it is recommended that power- connected through a tee to a common linegenerating equipment be located exterior to from the fuel tank, the line between theshelters instead of being made an integral part pumps should be of adequate diameter toof them. interml location of nowcr units prevent the operation of one pump fromwould increasc the difficulty of controlling interfering with the operation of the other.noise. vibration, and toxic fumes. Other con- With a tee arrangement. if the line betweentributing factors are space limitations, lopgs- pumps is too small, it is possible for thetics, cost. and the re! ,e difficulties of operaiion of one pump to pmeent functioningproviding fuel-supply and engine-exhaust of the other.;ystems. When several pieces of electricalequipment (e.g.. air conditioner, heater. CB Fuel intake fittings should not protrudefilter unit) must be connected to an exterior from wall exteriors where they are lughlypower supply, consolidation of controls into a suseptible to damage during loading, un-common control box will simplify cabling loading, and transport. Detail A in Fi. oQ-which must be passed through the shelter wal illustrates a method of recessing the con-and conserve space inside the shelter. wtins.

9.1q


FiguregM 7 Floor mounted SPce Heater With Quick-disconnect Fuel Adpter

I T? hisP jot IS fOr Mfmforwfrn OVy and st-Mdd not bettdw s~ criteriow, fcw t1*an of afnwwa

9-20


[ I ~AMCP 706120

iL

Ail U)

9-23


If-pi 1. - L O

FUEL SUPPDIf 6.ftE1/4* COPOEM vPRI~G

duIEatl ofvv dnwfw imguC.

9(W.22"t&


Fipw*e9. ?) Heswt Fuel Line With Ouo**-dwomwct Fiffinp

(Thn pfttpwh a nw wiwfiee oy m~d ~ud ntw be wd a # cmwnte fr 0*eOf mowI# ombtiomu)

9-23


the lowest pointofteehutpe.adi

The nstllaton f jt coditonesinvolves

caw f mltile nitsdespedforinteflor-

extrio intalaton.Suc unts reprovidedwith flexble quik-dsconectrtfrigerant

madeforpassng hew ine thrughthe

Thaypmffitnotabcnbeue ito

~'~"'~'~gIconnell the exterior comosents. Fthe 2 inteio hs-

tits s how ui e of4 c9 va-o22-ad httr

(2) 18.te Ch ife fw this purpos.usedI in sysotem e-el maWhssto esien tpz 9315alw the enviomna o trel unitiargslvanie ia# e thUM g thew wn ot ie rpetractedionto pathecsulterl durng; transtr

are thea wý atmoIs W "soudb cvrdre roeto. This 14AR DITIUIO -D ICLbef nv ar anly.due fresh air 14.1s i theTshlter wll. a

~~~~~elas pmetopTexteareieora comportents i factor hichuminimum. ~ ~ tte Avtiaear msthbe cosdeedo chenva doesnang suthears

T~~~he exhauttnofacmustione wheatre Thcelatopiand railstypeton snstellaforn-psivnizd pie. t isp~sed hrouh te wal t viro etralt contrlof pot abe shelterduigtasith

qonfty tepeatre stncur humdit the thelyureveia pad othat theexhauofmostur aVimpyaeth is osdeain.Hvn

teanergonlee.The eohut liet can ofemn eetedsg ngne aot


AMCP 7WI20

S.- ~ _POWER CABLE

EVAPOIRATOA -ODf PP UFAN SECT ION4~' o~~j i~

SPACER-

OUTSIDE WALL

CONDENSER-7

FAN SECTION CODJ!PON'PIPE NoPPLE

Fiure 9-19. Method of ftssng Power Cehe Between Condense and Ev'aporatorSectown of AFiultWl- Unit Irnwtlationt(m Fip" 9-7I7 for Comp4*let imvwlstion I

(TINS *'wing do not ivcaeINlY #VPMWht the latut d*sir toehniqfM and IS Show"t

for infor"wIon60 &VY. I

The function of the air distributing systcm 9-4.2 AIR WXSTRIBUTION SYSTEMSIs to promote uniformity of Conditioned airw~ithin the space. Condition. at foot level and Nblitary en¶iaronmerital control units arehead level should not differ siinificanily. designed with louvers in the discharge airTheme are three factors which contnbute to openings which can be adjusted manugli) todistribution of the air kinetic energ of .,he direct the air in the pattern best fitted to 1he

primtary air stream. convec-tion resulting Iron. application. Howevei. it is often ncccssarý todifferences ina temperature. and movements usc .luctwoik to carry the conditioned mr toFnerimted byi the continuous introduction 2nd the equipmcnt and spaces where it is neiededwithdrawal of air. These factors are strongly When ductwork is uscd, the krnserre grilesinflueniced by the desitun of the %upply reg- on the uni~s do not serve a uscful purpcme.asters Their size. location. spacing. the ratc of and they art removed in order to mrducr thrair flow throuagh them, and the direction given static presstire loss, ft the ductwork is sirnpl%to the air are all ;mpovtant facto". an c~tension of the air discharg opening., the


AMCP 7M16-120 A

project tiie heated air downward with sulfi-cient velocity to mix properly with the coolair at the floor level. For heating conditions it

-i is desirable to have the supply outlets at floorlevel. As it is seldom practicable.o provide"separate distribution systems for healing andicooling, it is sometimes necessary to make a

N-PT -I'TT*ING compromise which best fits the application.

liqutlre: 9-20. Method of Conncctiq It is normal practice to take advantage ofConde-nsat Drain to• the fact that only that portion of spaces

Air-conditioning Unit which may be occupied by personnel need beICosirtn:•y ul Tlr•oCompny) kept within the acceptable limits of tempera-

ture and humidity. That part of the volumeprille re'moved from the unit may be placed at above the 6-f1 level may be used as athe end of the duct. Ducts running to fresh air distribution and mixing zone, as indicated inincIts should be L- nnected to environmental Fig. 9-24. This requires that the primary aircontrol ulits upstream of the air filter in the be projected with sufficient velocity to en-unit. 1 1 he ductworK should include an access train room air by induced secondary circula-door for Filter rntmoval. ton in amounts up to several times its own

volume before it enters the occupied zone. ItIt is difficult to satisfy the requirements of must be remembe-red that an air stream

both heating and cooling operation with a projected horizontally will tend to rise if it issingle distribution sy::tem. For example, ceil- warmer than the surrounding air and to fall ifiug dil'fusers are quite acceptable for cooling, it is cooler. It is not easy by piojection andbut when used for heating it is difficult to entrainment to achieve both good air distribu-

tion and adequate mixing throughout theoccuried zone. The primary air streams must

A# not be projected directly into the occupiedzone. . Also. the throw of a register should not

ibe so greac that the primary air is "splashed"against a wall without appreciable mixing.

Ceiling plenums may be used for applica-tions requiring a uniform distribution of airover a large area.

The amount of' ductwork that may Ie"attached to military air conditioners is limitedby the recommended maximum externalstatic pressures. Th.,e are about I in. of waterfor ufiits rated up to 11.000 Btu/hr 3nd about1.5 in. of water for units rated between"18,000 and 60,000 Btu/hr. Because of therelatively small size of the shelters and.

FiCron927 Methodrof Attachng therefore, the relatively %hort runs of duicls.

Condonlsate Drain to Heater these recommended pressures are not likely toExhaust Line be exceeded unless the applicatimi combinesf

("his photograph is for tnfornet/on only and use of a remote unit, requiring externalshould not be used as a r rlirlon for the ductwork, with a shelter having extensive

dulug of similar Insaltlshori.) internal ductwork. Values of total cooling

0-26


AMCP 700-120

lz Li

Iý-

II

8

9-27


~; ~ - - ~static pressure losses in ductwork, the coolingcapacity will decrease correspoadingly.

.,~ 9-4.3 GENERAL RULES OF VENTILATION

TI-e following ;mi: some general vientilationrules':

(I) T he greatest volumne rate of air fnowper unit area of total opening i~s obtained byusing inlet andl outlet opecnings (.f nearly 'qualil ' area.

(2) Short circuits of air flow betwee.n

uinvas covers for protecting the openings on NwO sides of' a high level mayt .)rdanefltr side of units clear the air at that N-vel without producing

appreciable ver~tilation at 3ther levels.

(3) TrO cnhance the generation of convuc-ction currents by temperature differences, thevertical distaaice bctwt.en inlet and ',utletshould be as great as poýýiblc.

9-4.4 METHODS OF AVOIDING OBJEC-TIONABLY HIGH AIR VELOCITIES

In small enclosures with largc cooling loadsit is possible that the air flow rate required

a esnnltwill create objcctionably hig~i velocities in

persnnelspaces. L rrt oto hN, * environment properly, the air within the

- shelter must be circulated ur -xchanged witha minimum of discomfert or distraction tothe occupants.

There are !we ,roblems Livolved in the us':-of unnecrisarily high air velocities: the noi.segenerated in the duct system increases withincrease in air velocities. and thec occupants of'

v) uter forcloing penngs!he shelter may be made vMr uncomfortable(I,) uter whir closngdensing adby dIraft.%, especially when the coolin?. cycle is

vrhro igh which ci des in dra n being used. An air velocity of 35 ft/m in in

contact with personne! I-as be-en considered

Iliqirv .9,23, Arrdngemnent- for Protecting acceptable".

I xpterir Oopninqs in the Environmental L'-.essive air velociti )es usually have twoowroflfj Systern Dutring Tra'~tt basic causes: tindcrsized duct A or improper

((wfs rif 7rentComnwlyl outlet register design. In systems with under-sized (lt~,i, 2;r velociti-s must he kept high to

c dpn.ru USUAlly hased on free-discharyc maintain tihe mnass-flow rate of air required forauj 11~;.I' !li'. air flow rate ik rediucedl by proper operation du.-ing the cooling cycle.

9->


AMC' 7001-120

CONDITIONINGPROCESS MIXING ZONE

L I . .. .. _ _ _ _

IL

OCCUPIED ZONE

Figýyre 9-24. Basic Air Distribution Problem6

hi.comfortahle drafts and excessive noise controlled is small enough so that ducts arer,:cult. A system delivering 10% more than its not needed to distribute the heated air. Evenrated flow will havc a noise increase of 60%9. in the larger shelters and trucks, floor- andImproper register design will usually be pedestal-mounted installations - similar ,ocaused by attempts to increase the throw of those shown in Figs. 9-11, 9-13, 9-14, andthe entering air stream to compensate for usc 9-16 - can be used In semitrailers, vertical orof too few registers in the system. The result horizontal floor-level ducts, similar to thoseis most noticeable during cooling cycles as shown ir Figs. 9-2 and 9-3, can be used.evidenced by improper mixing of the enteringair stream and draft- due to impingement on Overhead duct systems are undesirable forwalls or tequipment, Some of these problems the distribution of heated air because they are.;an he avoided by proper selection of the size likely to have poor air distribution tu theand location of the air outle!.s, floor !evel, resulting in ex('cssive air stratifica-

tion. These detrimental ef1'ecis can be cor-Another way to avoid objectionably high rected to some extent by increasing the air

velocities is to reduce the air fl6w require- discharge velocity and directing it downward,nients by reducing the sensible heat load. provided the temperature differential betweenThermal insulation may be improved, Air supply air and room air is not vxcessive. Seeused to cool apparatus can be isolatcd from pars. 9-4.4 and 9-5.5.the personnel space and exhausted to theoutside. 94.5.2 CONDITIONS IN POLAR REGIONS

9-4.5 HEATING SYSTEMS Conditioning air in inhabited structures isprobably most difficult in polar regioni.

9-4.5.1 AIR DISTRIBUTION WITH AND Added to the extremely low temperatures,WITHOUT DUCTWORK low absolute humidity and the general use of

srructurcs of lightweight construction con-Heated air should be dischvrged at a low tribute to the difficu!ties. In addition to

level, so th:at its natural tendency to rise will supplying enough hea: to raise :he tempera-result in low floor-to-ccilirg temperature dil'- ture to the level required, it is necessary toferences. In the majority of heater installa- maintain sufficient air flow to prevent strami-tions ii shelters and trucks Ilhe space to be ficaflon :!,I stagnation of air and to supply j

9-29


AMCP 706-120

the proper arnount of moisture to raise the is designed to provide both heating andzehltlve immridity of the comfort level without cooling functions. The usual practice is to.n cx\cC of frost and condensation on cool design the ducts so that they provide opti-.st, Lcc•. mum air supply velocities during cooling,

when the rate of air flow and air density are

.tratsihcation can be avoided with air dis- highest.tri , ,u ion sydtenls, such as a floor plenum

ytuw, hich disteharge warnm air at a low For most applicationb to mobile systems,level. lhic itatural convection currents gen- the fan available in the environmental control

crated by the upward movement of the warm unit will meet the air flow requirements. In

air and downward movement of cool air tend cases where it is necessary to provide auxiliary

to mix tIle air. When warm air i.; discharged fans, Ref, 11 and Chapter 4 of Ref. 12 mayfrom overhead locations, it i:; difficult to be consulted.attai titif')rm lical distribution. Sub,;tantiald(,wrward comnponints of ejection vlocity The general rules which should be followedare needed in this case to avoid stratification in the design of ducts, given in Chapter 3 ofbut, n any case, floor arcas will be relatively Ref. 12, are:cool.

"I. The air should be conveyed as di-Tests'' on heating systems designed for rectly as possible at the permissible

polar use showed that condensation and velocities to obtain the desired resultsfrosting on co I surfaces may become a with minimum noise and greatest econ-problem when humnidifiers are used to raise omy of power, material, and space.the moisture content of the air. For example,it was fiund that frost formation made it "2. Sudden changes in the direction ordilficult ,o operate the regulating damper it velocity of the air should be avoided,the fre:;h-air intake duct. The experimenters When sudden changes are necessary atsuggested that the problem be solved by us- bends, turning vanes should be used toof ;in intake duct of sealed, double sheet- r. inimize the pressure loss.metal construction with insulation betweenthe twD metal casings. "3. Where the greatest air carrying ca-

pacity per square foot of sheet metal isThle following are getneral steps which can desired, rectangular ducts should be

be taken to mirinize the condensation and. made as nearly square as possible. Aspectfaosing problem: ratios (ratio of width to depth) greater

than 8 to I should be avoided. Where(i) Seal joints and cracks to prevent seep- possible, a ratio of 4 to I or less should I

age of cold air into the conditioned space and be maintained.the consequent cooling of surfaces over whichthe air flows. "4. Ducts should be constructed of

smooth material, such as steel or alumi.(2) If possible, adui insulation between the num shect metal. For ducts made from

more criti-al surfaces and the heat sinks. other materials, proper allowance for thechange in roughness should be made' ".

(3) Use no more humidification than is

neces',;,ry to produce the required conditions. "'5. . .. it should be recognized that, in

actual installations, I flowj resistances9-5. DUCT DESIGN may vary considerably from the calcu-

9-5.1 GENERALRULES OF DUCT DESIGN lated values because of variation in thesmoothness of materials. type-, of joints

In most cases, the duct system for a shelter used, and the ability of workmen to

9-30


AMCP M&13C

fabncaksi the -,>itern in aordance -,4th TABLE 0-1kthe dc~gn. Fans and rnotor-s sJhoird. E EN IAPDMXUMUC

thecefume bc Nclected to provide itIm VELOCITIES FOR CONVENTION4AL SYSTMWi sli~ht factcor of i~afetv. and darnpc-ý (Adsptsd from Re.~ 12, Chepw F

y hould be InstallIed in cach brAnch outictl - - -- -- _______

for Iaian-cing thle systrm %~fMwVetoctaiw. ftirmnn

**b Avo-Ad qbstructing ducts with piping.conduits, or stnt;;tut;Ji ffeflbm Un- - -vai

avoidable duct obsructions musl be Re*encti BuwIchng

strOutdoor~ Air Intakes 00 500drop. tht, length of which should bt at 250 350least three tin es the thicknews of the ~ ~ a 5 5tear-drop." fan Wes 10001600 16OD-2400

Mon Ducts 700900 1200-1800Some of these rules arr Alustratted in Fig- Brach Ow-s 500 800 1000

Branchi Risen S00 S00

9-5.2 DESIGN VELOCITIES Maximrum" Vnioccties. t1'iminOutdoor Au 800es So 1200

The veo-.itics Wt~ed ir, Table 9-1 . which dat Fotm~ a 0036rcported': to twse pven satisfactecry rmulls FnOwtiets170 1700-2800in cot enttonl systerns. mnay provide a guide noeSM W 1320for siectuig the - elocity of air -.n ducts. Since Brom- Cum 700100 1ow02800prc2ssure low--* increae Approxifnately as the ~ ucs7000 0010square of the vekx-.ity amW fan noise geneaz- Brarx -00 100-60tion increases With sttxti pressure Vek)ilttes ;-h~ ~ ~1~ 0 ~ faaae itre~tfe

me., other veioctpes irs xabie are lo net free maft~ ~ C QC C~jhftdby ASKRiAE Rteprtrayperrntivon

Cc;ýc se f~x 9iASJAE GuWeold Orta*IOw 196W

;<~~: V:should be kept low for quiet and cfficient~ op~atitfl. On the othe~r hand, thc 'exoctes-

b~u h utsx tes-4 the --cloit

~I~~'c~ ~'~Iis decreased. A&Neuati- perf tC)Mante willUsuAlY meull if suppl% duct , ciotitio. of NI)0"~o '?00 ft IwnW arv used,

N 0-94*L3 DESIGN PROCEDURE

~i~! i~k~o'~ ~The gmmWta procduzres fo duct dC'4n.1 1- atlc t~ 4ap *,ed Ffrom Ref I Z, 3are

~1) Study the plair ki .%Iesrctr n

I -atrzingr 21-w pmeitions of the suppl% outkis toI~] ~ provide proMe di%!ribution of 2air

Figure Si.25 o~~Afl Poor an f 3b 1~ sketch of thl- most comn nient

G oo C Qcr '~ duct 8votmn i~onnecting the fupplý outlelo


and return intakes with the environmental 9-26, which provides values of resistance forconlrol units. straight ducts in term-, of pressure loss per

unit length for each specific duct cross-(4) (alculAte tile sizes of tile main duct sectional configuration*. (harts are also avaig-

'ilt all bratichl ducts. able which pe.,mit determinati.n of the lossesthat occur in most of the common duct

5 t)Determine the total (net) pressure loss fittings and shapes1 2through the entire duct system, including theri,'Srn sytem if one is used. It' there is a return dut;t systerli, it is sized

in the sanio way that tihe supply duict,, are,)t llt: tlhree duct design mllhods' ve- sized starting with the lowest velocitie'. at

ui .y reduction, equal-friction, and Ntatic- the return intake! aud increasing them pro-regain tile velocity-reduction method is the jressively as the environnintal control unit iso1e h tst silted for the small duct systems approached,uiwo(l ir finobile military structures. As theterni indicates, the duct sizes are chosen so Dnapers should be provided to permitthat the-e are progressively lower velocities at balancing tile system for the conidilions actu-each branch duct as one moves downstream in ally encountered during use.the wair. duct. On the assunmption that themain duct is no larger than the discharge A refinement of' the described procedure isopening of the environmental control unit, to design the main duct first and to determinethe lowest velocity at the entrance to the the pressure head available- at each branchmain duct can be estimated from the known point: then each branch is designvd to h[ave aair flow rate and the size of the discharge pressure loss equal to, or somewhat le'ss than,opening. If the cross-sectional area of the the available pressure !lead.main duct is made smaller than the area of thedischarge opening in the unit, the entrance 9-5.4 DUCT FABRICATIONvelocity will be increased. The velocities inthe raain duct at each branch point are chosen Ducts used in the enviror,wental controlarhitrarily, except that they are chosen pro- systems of transportable military structuresgressively smaller as one moves away from the fit into the low prcs.sure classification, whichentrance. Knowing the volume rate of air flow includes those with mean air velocities lessthrough each portion of the duct system than 2.000 ft/min and static pressures lessenabl'es one to compute the areas of the ducts than 2 in. of water' 2 Tz.ble 9-5 showsfrom the chosen velocities. The graph in Fig. recommendations for the construction of9-26 may be used to obtain duct diameters, rectangular ducts. To conserve space, roundand Table 9-2 may be used to obtain equiva- ducts are rarely used inside the structureslent rectangular sizes. The pressure drop in under consideration. All duct constructionthe air path having the greatest resistance details should hi, in accordance with Section Ishould be calculated. If the pressure drop of the Duct Manual and Sheet Metal Con-exceeds the capability of' the fan in the struction for Ventilation and Air Condition-environmental control unit, it is necessary ings~stcms S:ither to increase duct sizes to lower thepressure loss or to provide auxiliary fans. In the' interest o1' maintaining urn2'rm

velocities --- accompanied by decreased turbu-Resistance to flow in the duct system is lence, lower resistance, and less noise -- el-

developed by both friction and turbulence, bows should have long radii and shapeFor a straight smooth duct the resistance changes should te as giadual as possible. Tovaries inversely as the fifth power of the ductdiameter, and it is proportional to the length.

T eb Such as Fig. c pages 50, 51, 60, and 61 of Rel. i, Ch. Z or Ref,Tables and charts are available, su a16, and p.o 284 of R cf. I',

9-32


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di~ u I;, lit , -. -

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I IA

I2 T)sxl. - .4i I

9z3


reduce the tmAnmb son of vibrations and th mng ftwni which can be clampednois, flexible conrietons should be used together with locking pins, without the use of

where the ducts are attached to the eseeron- tooc (in Fig. o-37). Some flexible datsapntal control units. This Ls espenially lpor- attached at their eno by as tsher over c

iant if the u ppe is mountea on vibraion flange and thedn tightening a metas co ng whichisolators. slampe the duct to the flrn. (See Fites 9-38.)

shi is not as roomeanent ra the f walFwhe 9-27 tnouf h 9-35 dlostte the apocus lockLo-pwi amraepnent, but it may be ac-

cation of air distribution systems to hrobile ceptabe if the aucts are not to be connecsedMilitary structures and disconnected often.

"1.55 SUPPY OUTLETS "-.7 SELECTION OF DUCT MATERIAL

The duct systemo ued in shelters may have In the aeting of matera for fabricatedsuppa b outlets tb the floor, in the loe ducts, dooreisio use as ducts or ductsidewalls in te er seing he fitni the desige ould conide severalceilg In siird floor registers for heatinga the factors in tepi to the propley of thesupply atir shouvd ve sufficient vhlowety to matoricss:Wread oued the room and reach the wallwhnre most of the heat loss occursp Low (1) Flame propdfation and smoke poee -vdewalo outlets should provide a horizntial ducing characterist rtcspread of s y air the floor area for heatngand be gnjustable to diract air to the upper (2) Odor t missn likely at opeslevels of the shelter space for cooling. Ceiling temperaturesand upper sidew'all registers are especially

effective n cooling applications, however, (3) Toxac emssinwhere usd for heatinE, UNxi T( ot effective-

Dtw of this stem nequiees wh air supply (4) Resistance to defold tion or detovelocities with a temperature differential tion at operating temperatures

bentacn supply in and room r emts than25•F. The general characteristics of outlet (5) Air tightnessrn*Wsen in different plamewnts ame indicatedin Table 9-4. (6) Resitance to mri~n infesation

". DUCTS FOR REMOTE UNITS (7) Moisture absrto and trnmsffuson

Duwtwork is also needed when an environ- (8) Retturtnee t.o mold growthmental control -mut is mounted emiote from

the shelter. Conion of the unts for (9) Resitance to corrso erosmon, andflexibl duct application requires supply and detaminatio.return air plenums, a supply grille. Nd anopening for t1w return air. A skid-munted H CONTROLSunit is shown with thae components in Fig.9-36. The flgure also shows the containers in ".1 CONTROL PANILwhich the ducts ar stored dring transit.

The control prod on envmmo ental con-Round ,lexible ducts are used to connect troW uns can be removed for rmote mount-

rernote units with the xheltr. 11-- =etion of wng Thlins ki it pow~le to ;m4ae fth Panelflexible duct should be kept as strs.&t and as where the switches can be operted c-short as pomble. Flexible duct connections veniently. The opening left by removal of thecan be made most easily if they are provided control pal shoul be €toed with a blak

9-6


*AP761U4

Q-3


ILArv- W

4,

imvII ~ ~ii

E~10

a 3.4c 4z6

c c

00

jh. W~c

C - -at

9-38 ~


F€

"I

Figure 928. Heater Duct Transit'on Piece

(This photo~ is for Infoenvmtion owly and shouid not be usa j aitlitn for the d~tor Of SrMdJF zrMt8118r0on$.!

cover panil. It should be noted that th- Wonrcr or other %pot where there is no

protection against radio frequencn inter- ý.-rcuiation. nor should it bN lo-akted directri

ferencc wIll be destroyed unless the cablc in the path ot in a• blast The thermostat

used for remote mounting is sbielded should bc plakcad in an cxp4-,-d locat:on.

%here there i'+ norma- circulatif-on

94L2 THERMOSTAT9E-6.3 DAMPERS

The temperature control cir,.ustn ol en-

vironmental control units includes a therno- A damper v. prodejd within cnvironmertal

stat which provides both heating and .ooling •ontro)l units lot ontrolling the amo.cunt of

control, usually withm the range from 40+ to ircsh air entering the unit It the irdle? grille

90QF. In small installations. the thermnostat %hould iv laoed .. ae should -e taken to

may be left in the unit. but in large intali•- as,urc That enough a-r itesh or rt

tions. better control 3an b< attained b% Tur passc' ,%tsr the csa[xrator to jstod the

removrig the thermostat from the unit and build-up of ikc -rn the o0%

mounting it in the conditioned space In the

case of heatcrs, the temperature thermostat i% Additional damper- are usual!: provided in

always mounted outsde the unit -or proper the duct %)stem. if one is usecd. so that air

control. it is very important to locate the flow rate, in different branches can '0, J-

thermostat properly. It should not be in a juste,. to meet vancus requirements

9-39


ACP 0-120

Figure 9.29. Heater andm Ai Installation WithConnecting Ductwork In erni-trailer

(th/s photograph Is for Information only and should not be used asa criterion for the design of similar instal/latins.)

9-e.4 AUXILIARY CONTROLS such as the overheat controls, high pressurecutout switch, and back pressure regula-

Theme are a number of auxiliary safety tot - which are described in Chapters 4 andcontrols which art. part of the internal OIr- 6. This chapter considers only devices which,cuilry of the units and which, therefoie, do are inst'lled separately, A list of safetynot require any special attention during instal- precautions to bc taken when working with.ation. These include the outside air thermo- air conditioners is also included. Protectionstat, high temperature control, high pressure against chemical and biologica; contaminantscutout switch, and back pressure regulator is discussed in Chapter II.which are discussed in Chapter 4.

9.7.2 COMBUSTION HEATER OPERATION9-7 SAFETY CONSIDERATIONS

It is es.ential to make sure thatOthere he a9-7.1 INTRODUCT'ON continteus supply of fresh air to Lombustion

heaters, so that there will be no chance ofAs most of the safety fc-' ,re used in depleting the supply of oxygen in the con-

envircnmental contro! units are ;_ arporatp-l trolled enclosure when such heaters remain inin the units, they do not require special operation ror extended periods. The combus-installation procedures. These include items tion air intake line should txe of the size

9-40


Figure 9-30. View of Semi-trziler Environmewital Control (nsullition(This phctW~'h is for wtomanrion only anz viouid not Or tw as a cml*f*ofl

for 00 cta'r of shmwe Isintoo M.)

recormimcnded for the unit. it should be a, temporanlb overloadiag tue enroronmentalstright and short !ts possble, and the inJet control units In such cases. an emergenc)end should be free of oUstructios ovem.de switch should be p-o~ided to bypass

all safety devices and therinosatts to permit

It is also essntial to imisure pioper exhatst emergenz) opetrator. 4f thie ss-ern iithu

of the combustion nroducts. Installaticn of a rnormal protection against e.-mcal mechani-condensation drain in :he exhaust line. a: cal. nr thermal o'erload:' ThL' svfch is todescnbed in par. ?-3.3.3, helps to p;:vent be used on1% for short periods when emer-clogng of the exhaust line b.i the fre.ing of gpnm conditions take pecedern,e over Themo:;ture in the exhaut gas. probal'it% o0 rmajor compornmi faduwes It

the applhatior requires it ar ;,uxfla.

As meintioned in par 9-3 3 3. the heate: method of :mnimai %ent-lavion should he

exha';st should not be installed near any fresh provided in cas' of cJmpvneni f3a'urrs

a" mnlets or windous and doorn9-7.4 GAFETY PRECAUTIONS

9-7.3 EMERGENCY OVERRIDE SWITCH The fohowing list ,!.: al*I )-recauti•ns

taktrn trom Ret 5 should he fol]oueJ 'her.1v, some ap-hcations. it ma) be anticipazrC working w.th air ,1ndt1ore.P

that occasonally it w.ill be cssential to main-

tain environmental control even at the nisk of \nr.! !ern,-,t an% panels :- the air

Q- i


Pr

AAFigure 9-31. Heater and Air Conditioner Discha-e Ducts in Svmi-trailer

17Th,% POtO9ppo is for no,'tion v only and focld mor be& & as a cricrnon for thi

d of xin•!. ,nM-01t.Uo'u.

conditioning unit without first discon- -4. Stop the unit immediatel) if exces-nc"-Ung the unit from the powe-r source siv vibration or uiustal notses oc-.r

"2- Keep hands away from the fanN "'5. Do not us wa•ter on a motor firewhen the unit is operating. Use CO.

"-3 N'ever attempt any repairs or inspec- -6 If the motor or Compresor shouldton of the electrical cirtcuit inlte•s the heat excess'el). stop tnc unic immedi-unit has been disconnected from the ately anL' investiptcpower wurce On units •i-th tram powerline filter. ( RFI;. tht capacitorm %houldbe dicharged e.ectncally before a•; . Should liquid Reirig.rant-2• cometempting repair of the electri cartrust in contact aith the skin. 'he xtjur

9-42


F~xv 942 Cory~se !MtM - of mymwiwgWM CcWFVXW Diwnwv,* A7infvTam Phftvwhap is fo MA"Mw~ woj Sw Ax"d AN be &ed a ita~mr Ar f~t

1saxud be treated the sa~me as though the3 ps h been thmz&ate frrmn the lineskni has been frostbitten x frozen. and that the ame is well ventilated,

-9 Dow ok k~ pc h 10. Do not meaem ckeat coils.Refr~crt~- 22 may be leaking urdess 1.4 EPAICE PROVSHMNPANUiAte V-entiation ..4 pfaovdd.

"41 WflDUCTIOM~-9, 'Never use z torch on a iefngetant-22 pipe line until it ts dletermined tha! *11 The o0ectzve of ra~aiteniuncer Mto keep

9-43


I'r

Fp ft9-31 View O'f VunltiD*(' CVMffP for afwgnf* TAW Ulm,

9~4


-44

al.000 OTU/Mftam €•ONT $ONetE*

HEATER

Figae 934. Interir View of Shop Van Showun Elecromwc EwiuM andEfvMrwwwsW Cons fmitsa

d, ,' of aM .,oi w e u vo j

equipment operattirg satisfactonly with as neccsway to remnovc a painel to replace alittle effort and .st as possiblc. Pans that component. it should be a simpie operation.nqwre pe hdic inspection or sericing shouid If the panel is famtened with screws. theirbe readily accessibte Provisions should be number stoiud be kept to a rmmmummade for rapid rer•ioval and assembly ofcomponents that require smevcing. If it is ThKre awe two types of maintenance., pre-

ventive and corrective. Preventive mamte-*Anext•me 1it of roirsr: o•1t•n "t • s Vven w I &W name dtea' with inspection. se,•wing. and

11of Flet. "I. sbk* ") Ws tv e (ciWfo &-Ms mat, mtoLbbt*) mrnor repars. Corrective maintena.• in-

9•-45


S&PPLy GRILLES

Flgr" 93S Corw,,w? Aon Miw Roukswd for Flexub,¶e Duct Amkw

9-46


I / v ! i \ '! [:2 ;i

IIMF,

4 44144I / . ' - -- .. ./ i ..-

I ' € I *I.

_ ,._ "I __L- •Z I-I l

O MALE CONNECTOR

© COVER, OR FEMALE CONNECTOR OF FLEWOXLE DUCT ISME FIGUAE 9-30)

@ LOCK HANDLE

® CAM LOCK (TIGHTENS AROUND PIN)

Figure 9-37. Crawing Showing Cam-lock Arrangement for Connecting Flexible ,.uct to Plenum(Courtew of Trene Cotmany)

volvcs major repairs, replacement, and over- corrective maintenance, since i'orc time ishaul. The designer must always recognize the generally available for performing such main-need to make any maintenance operations, tenance. However, components which arcparticularly the preventive type, as simple a- likely to experience a relatively early failurepossible. Inspection, lubrication, filter clean- should not be buried in inaccessible locations.ing, and oil changes, among others, should notbe impeded by obstructions in the form ofcomponents that easily could have been lo- 9-8.2 ACCESSIBILITYcatcd elsewhere, On. the other hand. suchready accessibility is not so demanding for It is important to plan mechanical connec-

9-47


\ -CLAMP / -4ULAI'COOUT

FWV we 8 Dres*M $AOgWfr Aktho of Attachig F/*zibje Du-.-: toCwmrw WfToo 4twt Rg4

tioms so tw MainterAnce poits renma access to ervironmental control unitsaccessible. The arraaxpmeat shouAl not mak: mounted too hah to be reached otherawse.it difficult to paform operations which must They should be bIht enough to be handled bybe done rmpa•y, ah s the replacement of ot M= The 1,mI. required for servicing andar and fuel filter- bldaors which must be repair can be reducW by proMvng mountingviewed nrelady, such as fuel-actent and bWcket fw the acces ladders. If the ladders

l4ev indicatoM shouWA be cearly vale. are to be used neam power lirn. wooden ones

The reftfimt sght i should als•o be should be conidered.sudy see. It is deAsrble that it be peuible toperfornm comoon noubl hot o oquations -.63 CODING OF PLUGS AND AECEP-without mqotr ewwi a of the system. For 7ACLESexsmpk. it a duwsbe tdot samce v-alveswhich emable a repskmen to measure the The use of unique geometric shapes fmiWake and outlet presma of the reftea matcWing plup and their receptacles. andtion sYW= be redily accesfibe. Similary, fo ~roof location of rwae and fernale pamrtPam foi "dW*n the cooln SUt Should are excellent mean of avoiding nisatch-.be neddy accessible. Color coding of plup And receptacles is aLso

an efficit means of anuring proper identi-The conditioned w supply and mtuml air fication. However. if the number of plu-

glles must be ecceubie for normol semc, receptacle pain exceeds eleven tpreferablyand maintenance, fewer) there could be a problem of color

dis"tnation *ith vaiations m in ununauon.Thea have been cans where access door In such cases. numerm coding is preferable.

handles have become too hot to be handledde to sola radiation or becaue of neames In selecting colors for color coding, oneto a heat sotce, such as an engme exbast Should try to accommodate color-weakline" Z. The use of material of low thermal people who do not perm-mve :olors as noMmcoaductiit md low srfsce absoptivity will peope do. Yellot and blue are colrs ituchhel adeviate the problem due to sola r'4mw Vjb !WqWM +- !S- ,4sdon&. Hatin from other sowres can bereduced by care in locatim of ptu that mustbe handled ad by inraMig the resistawe of "4A PWOTECTION AGAJST OETDtI-heat now paths ORATION

Laddet, shoud be proided to faituate Eawironetal control units are desated

948


a=d manufactured in accordince with specift- bon are tho commonly used to controlcations which provutk protectin Ap st de- excasi• noise and vibration. Mechancaitenkwation by vamous agents such as funus. islation is bet muted for controlling forcedmoisture. temperature extremes, and salt vibratbons, and acoustical absorption bs theatmosphere. Other components of the total best way of handling auborne noisr.emironnental control system, such as duct-work and acoustic and thermal inluation, In the case ol cqwpment used with mobileshould be selected in accordance with the shelters for military opcratiuonm. the oontrol of"sawe pwoe.rtivc criteria. Protection Apitist vibration is complcated by secral factor,deterioration is not a matter only of material;election, however. Proper design can (1) Not only must the noite level insidediminsh exposure of senmtivc components to the shelter be kept to an a,.ccptable level, butthe deleterious agents. also the noise kvel sensed in the external

ope•,t~onal area must be .on~adered.

Occaionally, damage results from unex-

pected sources. For example, the surfaces of f 2) Mobility rcquucnwnt5 dcmand that thecomponents attached to air conditioners may equipment be as light in %%right %. po-wble.become cold enough for condensation to but this tenas to increase noise problemsfoirm on them. whch could contribute to because reducing mnaus leisen vibrationintolerable deterioration. Increasing the ther- dampingmal resistance of heat transfez paths to suchsurfaces may help prevent condensation. (3) The ngors of usage i nuhita* opera-Where condensation is unavoidable, the use of tions require desgn of rugged equipment withmoisture resistance materials will alle-vmte the a trununum of resihent mt,-ronnr tion and apitobic. nununum of relative motion btiOeen %.anous

components Thus the effect of noise control9-9 NOISE CONTROL by vibraton isoLation is mininmzed.

9-9.1 INTRODUCTION 9-9.2 AIR NOISE CONTROL

Problems of excessive noise or vibration it is %ell to introduce this top.- b%orgnate in the periodic motion ol 3 struc- necommending a step whish .an •e taken toture. The response of a structure to pcnod•L prcenrt the generation ot ao--iabie .. u-.st.energy input depends on its incrua and noise. This is to munimize the power asailablcflexibility. If a structure has high inertia, the for coniersmon to sound' b% keeping Thc taramplitude of oscillatory motion generated b% power as low as possible he acoutik poxwethe periodic energy input will be low, and the generated bý a fan in an air-moaing s)seitcstructure acts primarily as a path for energy varies as the fifth power of the flow rate'transnussion. If the inertia is low. the struc- thercf3rc. even a little excess tan power canture may undergo forced vibration. respond- result in subtantia3 asoidable ,ouiust, noiasrig like a rigid body to the applied force. The required flovw rate should tb .alculated asHowever. if one of the forcing frequencies of ac.uratel) as pFx•sable. and an% proeision )orthe input energy coincides with one of the CIMe's au flow .apa,.at% %houk' be kept Ic a

natural frequencies determined by the flexi- ninimunibility of the strtcture, the phenomenon ofresonance causes a cancellation of the oppos, The .omimon teahniquc ot air noa• ,ontroltmg reactions resulting from the mass and is acousti.ai •,•orption ,hi.h ha. the objc.-rigidity of the structure. and greatly amplified tie ot redt, ing nurse bh% mcr, epting awvhornevibrations result. acouststai energ. The an i% allowed to flow

thirough smull passagr% wacre its cnclg% i%The techniques of isolation and absorp- dissipated bt fnction against ,ac walls ot c

•4Q.,


pmap One may use baflks or acoustic tdi tical none generated by wz flow includemade of porous nmtnah readily penetratedby air. The efficwticy of absorption depends (1) Line au plenum wail with acousticpimarily on the ratio of the thickness of the inulation.absorbent material to the wavelength of theimpinging acoustca gnal. the greater the (2) Use ducts with acoustu. lining or applyratio, the gater the absorption. Thus, acous- liig to metal ductwork. The duct should betical fils arc more effective in reducing lined for a distance of at least 10 It. startnghWghfreluency nogse than low frequency at the environmental control unit.noise. However, •rictional loss is not a veryefficient mechanism for reducing noise, and it (3) Install a noise attenuator at the airmay not be effective an controllang noise o irntake and dscharge openmrn. 4Sec Fig.hig inteisity. In such cases, one may use 9-39.;&acstical barnersm which may range fromrigid endosures of the source to special (4) Install acoustic absorbing matcnl ,it

earmuffs for the receiver. stratcgic locations within the enlosure Fhcuse of acoustic ceiling Wtie is an example of

Prefabricated mufflers am avuilable for this method.insertion in ducts. Their primary advantage isthat a given noise reduction can be attained 5ra shorter lengt, of duct than would be sourcc and the listener. If the noise to berequired by other mcans. Although there may attenuated orginates in the cnvironmentaibe a 5ubstantial pressure drop through the control unit. the suppl) and return air shouldmuffler section. it may be much smaller then be ducted through the barrer The radiatingthe pressure drop through the length of lined sound path thould be .mide as mndirtt asduct that would be needed for equal noise possible and the barriers should be as masiscattenuation. The net amou,.: of pressure loss as practical to insure .. ,i acoustu, trans-is duininished if thre mtf-lr e:n b•e ,.f, nui_•on !

wher there is a straight. downstream sectionof duct long enough for pressure recovery to (6) Choose inlet and outlet register sizesoccur. Manufacturers provide pressure-drop. and duct sizes which do not >% eld hith airnoise-attenuation, and instlation. data for tlocitL".the various mnodeLs of mufflers on themarket*. (7t Des the du;t system for minimum

flow resistance (see par. 4-5 1I

A multiple-layer material which combinesone or more lead septurns with alternating eet t the least air flon rate that willlayers of polyurethane foam is available for meet the eninentai .ontrol reqtiremcntsnoise and vibration controlf. The mitenalcombines vibration damping, noise absorp- - MACHAN1CAL NOISE ONTRO.tion, and sound transmssmon reduction. It isintended primarily for application direciy to w ch an ical nose o rces t o in supportthe equipment which gene-rtes the unwanted which transmits tchncal forces t.o its supports

no•.and thence to the s' arroundmnr stnructur To

isoiale the structure from such disturbingforces, separators arc installed between theStep that can be taken to reduce acous-source of mechaical vibrations and the areafrom which they are to be excluded. Sepa-

"AMAW~o 116996 Offi 9h Q Wt Mt 0WhiOvK"MCm.. Auwy NY. i*dsla Acowos Co.. New rators con•ist of coil springs. elasturner pads.Yo-. PY.. apd Ko~ Co. 1=c.. balooae. M&..C i or combinztions of them The natural fre-fulmmetwaus by l TU• Sma, wo Conqical. ln,• 5i5

iMe o Av- Me york, %Y I0022 quencý ,'f the separators should be con-

9-50


t4'1

F19Ufe 9-39. AttrchrnentS for Atrei uVring Noise de/- InWA e na.

Dischrge' Openings of Envwronmen••; Control Untts•-

•tderabl) lower thin the (requuen-. tel+ vi .c en UrJ -AcCT loaded -flj rcO.1'4disturbing force in addition to picniming uis 1TCqucn,.. -An be prev-cd .direct contact between the %ibration ,out,,"and other pants of a structur,-. the wparator - ( L ,,cs M31 I-Iincreaiw the impedance mismatch izt theboundary and proportionatch dtrcas+ the %hereefficiency of energy transnussion The u•w ot4 -iu aboirtim on an automobile engine v, in ( o rvnn Itrant )I the Is,:ato. !b irexample of the isolation technique

L lo3d supported b% the isolato: lbThe d4tutbing frequency !,, ma- be de-

fined as the lowest frequenc, of forced Pic transmission ,crstant I of t~t. ,.Qa, -1;vibration. i.e the vibration generated h% expresse, inc per~entage of the tcd! ithratorýrotating or reciprocating rmachiner% A- a force '.hich is passed through th ro.la -- atgeneral rule. isolation aganst the Iow.est dr- each irequenc) An equation his bci. de-turbing frequency of the system will provide a selnped to calcul ýtc this .onsuan: from thegreater degree of imolaticn for the higher physical rharacttnst:,7 of the systermfrequencies. In the case of a bclt-d-vcn -

centrifupl fan. there would be two dz.w:rete T -

disturbing frequencies of vibration gencr-ated. that of the drive motor and that of the

fan. The fan usually operates at a lower -

rotating speed than the motor. therefore. if However. Eq 9-.' is tsable or]) in i•olator%the suspension for this system can isolate Laving low nysteres"s losses The shear- loadedvibration produced by the fan. it will providr mounts and the pad-typc solators ha-e ,ucha greater amount of isolation for vibratlo., hih ýiysteresas tht the abo~e equztton doesproduced oy the motor not provide a good estimate of the trans-

rmuwon constant. Values of transrrmassion con-The natural frequency I. is the freqvznc) stants for typicai isolators ar. shown in Tablc

at which a vibration tsolator will r c-nat€ .5

9-5 I


-NC mf- 2

TAXLE 0-6

VRANUISMSION CONSTANTS FOR TYPICAL ISO.ATORS

flat" awZýSj.j hvnm tuaawnabdokp

ZA ~ CF" $1 00 ~ 3 10"00 12 X0 3 I

10 to 10 05 1 @

was ~ i~~ 2 1i5 17 7 4 3 i 0 .'tI im 40 .4 9 6 4 l

• .•,Copyrighted. Heprinted biy permission ofbC• Heating, PipiA"g dnd Air Condit'oning tro

paper authored by W E. Thale.

A new ,•{ho•J of norse conItrol, which h~s du•.1wotk by u•e ot 4 resihent ;ra.•itiorprov-d to be a juwei1ul reined> for resonant pre•.. such -s /sbcstos ,.an•a isee. hg$ '-40vibratio.s. •s constra~rr'd~ayer dahiping: A flexible -onn¢ctien is p~arIiuiarl> re~.onmrne method einptoys a nri~d|)-b.4_ked La)er of mended if iw ,,and z• rnouitd on isoa~ors

Cprola h td mnRtenat applied dueItI> to thesurfac.- of the voratng strucre ,he ,aon- r3) Noises .. auscd b> du.t flexing tdue tostront of toe ngad tcWkng criusem theo later o thertmal expanslon and aontmKtwFi o'4-40)vitsco•s•tic !na!ens to urindego shear dtion m in fx ternaJ air prLs ur.-rt• •an b .onv

mation when the structure %ibrales. and the trolled ti bracing use of shcet metal ofmechanical vibration efrer-g Is signuficantl) adequzic gage. and asotdinj high *idth dcz•hdassipatcd by Lonversion to heit The ef- ratjo•.ficiency of the method depends not only on

the energy-dtwipation capacity o; the damp-

ing layer but also on the ifficiency .vth --

which cnergy is transferred from the pinmaryvibratng structure to tht: damping layer. tnelatter requirement !Lkc. it 2mperative that .- .

there be suitable mecnamcal coupling of the

three layers.

Method of reducing meJaIrumcal nois tri-clude

tI) Mount equwpment on vibration iso-lators.

(2) Separate anlet and outlet environ- Figure 9-40 Arrve.,oatpotn of Voe ,n

mental control unit from shelter openings or Dru'ge Du woork

9-521


AMCP 706-120

REFERENCES

1 Stanuards of U.S. Army Human Engi- 7. ASHRAE, Handbook of Fundamentals,neering Laboratories, Aberdeen Proving Amer. Soc. of Heating, Refrigerating andGrovnd, Md. Air-Conditioning Engineers, Inc., New

York, N.Y. (1967).a. HEL Standard S-2-64A, Human Faa-

tors Engineering Design Standard for 8. F. A. Govan, Air-Conditioning Design,Vehicle Fighting Compartments, June National Research Council, Publication

- 1968. 709, National Academy of Sciences,Washington, D.C., 1959.

b. HEL Standard S-6-66, Human FactorsEngineering Design Standard for 9. R. J. Kenny, "Noise in Air-MovingWheeled Vehicles, Sept. 1966. Systems", Machine Design 40, 138-150

(1968).c. HEL Stanaard S-6-68, Human Factors

Engineering Design Staneard for Corn- 10. C. R. Hoffman, Modified T"-5 Barrack•-munication Systems and Related Controlled Climatic Hteating Studiej,Equipment, Dec. 1968. Tech. Rep. R286, U.S. Naval Civil Engrg.

Lab., Port Hueneme, Calif., 12 May 19642. Trane Engineering Bulletin, Military Air (AD-600 619%.

Conditioner Selection and AFplication,Section B-10, 67-86, The Trane Co., La 11. R. J. Kenny, "Fans and Blowers", Ma-Crosse, Wisconsin, 25 June 1968. chine Design 40, 151-173 (1968).

3. Study Report, Electronic Test Set No. 3, 12. Guide and Data Book, Systemn andVol. 4: Mechanical Considerations, ATE- Equipment 196 7, Amer. Soc. of Heating,MTE-L-4, Radio Corp. of Am., Aerospace Refrigerating and Air-ConditioningSystems Div., Burlington, Mass. (AD-476 Engineers, Inc., New York, N.Y., 1967.234).

4. A. 3. Reynolds and S. T. Hovey, Mobility 13. R. D. Madison and W. R. Elliot, "FrictionAspects of a System Design for a Depiloy- Charts for Gases Including Correction foraspectsofnaiSyssane DEtrtign For aipioy, Temperature, Viscosity and Pipe Rough-able Reconnaissance Extrac-ton Facility, ness", Heating, Piping and Air Condition-Technical Report No. RADC-TR.65-222, Ing 18(10), ) 07-1i 12 (Oct. 194(6).Reconnaissanct-IntclUgence Data Han-dling Branch, Griffiss Air Force Base,New York, July 1965. 14. R. G Hucbscher, "Friction Equivalents

for Round, Square and Rectangular5. Manual for Trane Compact, Verrfral, Mill- Ducts", ASHVE Trans. 54. 101 (1 948).

tary Air Conditioners, The Trane Co., LaCrosse, Wisconsin, July 1968. 15. C. Berny, Ian and Flow, The Industrial

6. N. B. Hutcheon, Air-Conditioning aihd Free Press, New York, N.Y., 1954.

Comhfort, Occupational I lealth Review17(2), 3-11 (1965). Also available as a 16. Carrier Design Manual. Chapter 2. "Airrcbrint, NIRC 8625, National Research Duct Design". Carrier Air ConditioningCouncil, Ottawa, Canada, July 1965. Co., Syracuse, N.Y., 1960.

9-53


AMGP 7019-120

17. Trare Air Conditioning Manual, The pOrt, New York (AD-481 331).Trane Company, La Crose, Wisconsin,39th printing, July 1967. 21. AMCP 706-134, Engineering Design

9 Hndbook, Maintainability Guide 16r De-

18. Duct Manual and Sheet Metal Construc- sign.lion for Ventilation and Air Conditioning 22. V. F. Galbig, Engineering and Envlron-Systems, Section 1, Low Velocity Sys- mental (Desert) Test of Semitrailer, Re-lems. Sheet Metal and Air Conditioning frigerator, Van, 15-Ton, 4-Wheel,Contractor's National Association, Inc., XM347E1, Report No. OTA/TB5-1963. 1401/480, TW-501/14, U.S. Army, Cru-

19. Guide and Data Book, Applications for nonce Test Activity, Yuma, Arizona,1966 and 1967, Amer. Soc. of Heating, Nov. 1959. (AD-229 076).Refrigerating and Air-Conditioning 23. T'. P. Yin, "The Control of Vibration andFngineers, Inc., New York, N.Y., 1966. Noise", Scientific American 220. 9h-l106

20. Installation, Operation and Maintenance (1969).

Instructions, Vehicular Environment 24. W. E. Whale, "Isolating Equipment forControl System, Harrison Radiator Divi- Vibration Control", Heating, Piping aridsion, General Motors Corporation, Lock- Air Conditioning 38, 122-5 (1906).

9-54


on~ i10Nti pIa

CHAPTER 10

COOLING OF ELECTRONIC SOUIP'MEN'Y

101-1 COCliNG METHM)CS IWtO a'ýount when chooXit-Ul tltc Wowers forthtic tooIing tytterns 14. riccew-ay. di.--b and

thc (..'ethod niurst whnI used t. oo~l iacs rnaý bec used mubdc the cabinct toIocstrora,. equipknte t* to circ.ui-- outsadc Cirectc the foib of air wo Par1wutar ),t spots

filtcrt-d .ur through thr "uiect5 contauiungthr N~uipuient -:erni -ratuve rejf4lstlon ean I hc ptroocr aksign of A L.oolhng iystrm to!N.- ahieir-4 bý vaiying the ralte of a - 1iow. It ',,xtrorw. rquiptarws a ki fo*Ie~gge ofAdCQUatC ~oofing -.Annfot be amtmn,-,j *ith tfle tcvilnturr lirnuts witfljn which thcoituidc air. jir .onditorting must be cm- cqtiP~nt tLan iunk~tovs prope~lý Difse-rntlplo~cd, but thn. iiiji b< needed othh, lot p~art, v: _- Vcn ýiicm n A) hav~e owtcc0ookfl equipmc-nt '%hich v. ctrrietnc ternl- diltzrcrii toictamrix-, A .ornpulei, fcr ex-pcriture cnaI ficat .on~c%:tcd froni clie,.- Onlr nu) htwv 4 Mrn flon corc "Pabic %.;troniý. apparaiaus into the ý_p4icc o%.cupwed b% wihstandint: temperaiwne %sp tw i *hik-

penw.rilfl C:In bc e .itsd hý bO!311fg thr the fliti.tpe_ rma) operate ~~t~lmzan~rumcnt ra. i. tnd pros teling _ prae ord-. within ite ranVe v!A tu CJ(4 -F-orcxhav-tQ dirct!) to the ouU-_1- of the 'ýari for tLnwljý conponerit5, it is rs~sntwa to imrt.A,.11 arUsd -.n c'ý':nhij thte 4pparatus If Most ttht utv of !ýu~t.t~ac Impetizatrc flaveý tt131 zh,ý etc.-tronzý. cqctptmnit doc~i not praduice componen~t at a rwe ade~uate to wwintaim thes tush wTcmeiatusre i-m in 1hr c, %rlmg anr. t-Inperatore O1 fl W Tp~le~ *ithsrn iti,

po isoin oft. WPAnstep rlthw?~st to the Outiide& iolerane. I hr pobktm -an. bc %ol d usang

mzy e 1-mtitd to fhowst components that hr-at tranme- the-er Ln ita-4 01ww of wplb-_rju- a hdig ternpcrature n',c und thai fgvomeU-ieý Howe--cr. Ofiti th oiifiguiatton n

~oud -wi.Oker~ieat M<l rezurl. air zomplei ari the- temr-raturr tokto-A.r- i--

Sonr air :owhtiiorioag flnstdal~torl are de- rml.if rru; shc tlo %ioakc an c~ptri-upwrxj to citeulate ;h,. ,oiu-tioned at,, to (he rnwnta: dtde. Tiuation at the 'oe4in' au rei

*m~tr.T'r.mat tin~t. then tW thte clcctronltczabinets klth( uejn th,: -, not t~w PcortCMks#ni Pletm..d ut ýo'L;hnfVictrom". equip- A prdtctka] example of Uhec 4aiTa l r

cas.es whirn: CHR. proteIAion re..iairemenits in Ref I Appendix 1.) afM Id an;e- xhmu", 'S-ý *x-' Xi' !a-!e ef tnts -ungt'ht 4'nX~ outsul~e 4.1A * i~t$1C

vr~x.Iuse I%~ that it nua. .xiww the ;operatvr*\ te redwtc thr aU-'nditwon~

rcatrit 134C of tihrc~ e44wplnerit 'a-nts rUI-t

r- h--tr4~ -ký4d ;t the ei-trou, draw- nth't.

air, the temapcraturv of wht&0 maý r_- toa- %%t"h .onsidcr- the- pto;ýkcn L-f :oruoV-ingjsiderahly fromn PeAking into thc jersonnt! ;hc trinffrAltme of %an- ani tre-r

quartet It is imtpOPasint to take ftltte kww*~- c.koed dk'ctroruA. equiprmrtn Vith, pantt';Uws


AMP "76-120

empha-sis on its relation to equipinen, per. the maximum allowable ambient tcemperatureSforwance and reliability, for its components is 150*F. Conditioned air

of 630 F dry bulb and 60*F wet bulb (satura-tleat pipes, which transfer heat basically by tion) temperature is available for cooling.

aipor transport and capillary action, provide a Assuming turbulent flow, (i.e., good mixing)new method ofi removing 'iaste heat and what cooling air rate in cubic feet per minuteleveling temperature in electronic equipment, is required?The uses of these thermal conductance de-vices are reviewed in Ref. 3. In Fig. IO1, Point A designates the state

point of the processed cooling air. SinceThermoelectric cooling methods being de- moioture is neither added or removed dunng

velopud may provide better solutions for the heating process, the sut, point movessome problemns, particularly for ipot coolii,g', along a horizontal line to Point B. which

represents the maximunm allowable tempera-ture (150'F). The difference between the

10-2 COMPUTATION OF COOLING FIE- enthalpics associated with points B and A. isQUIREMENTS 48.0 - 26.4 = 21.6 litu/lb. The mass rate w

of air delivery required is:The heat load on the environmental control

system due to electronic equipment is equal (Bttihr)to the heat value of the electrical power w - , lb/hr (10-2)dissipated as heat inside the controlled en- c.hange in enthalpyclosure. Except for power transmnitted from of air (Btu/Ib)the enclosure ias radio waves, for example)this will be equivalent to the operating powerof the equipment. This load often accounts Therefore, to removc heat al the r.mc of 1000for a major portion of the total cooling load. W or 3.413 X 1000 Btu/hr, the rate o air

flow required is 3413/21.6 = 158 li/hr. )iiSince different kinds of electrical equip- the psychrometric chart, one can read the

ment have varying usage requirements, a specific volume r of this air in the cool state.so-called usage factor is defined as the ex- which is 13.4 ft-/lb. Then, the volume rate Qpected power requirement for a four-hour of air dchivery can be comp~uted.period divided by the power requirement forcontinuous, full-load operation for a four- Q 0b lb/hr)X (t/Ib) J0-3hour period. 0O (min/hr)

The total electronics load q, Iis I: Thus, to perform the cooling work for theequipment of this example.

,et 3.413 2(Full Load Power in watts) (158 X 13.4)/60 = 35.3 elm of cool air arenecessary.

X (Usage Factor), Btu/hr (10-1)The ca!culatiois can be simplified for

The summation extends over all equipment in commonly encountered causes by using thethe controlled enclosure. following formula:

One method of computing the amount of Q 3.1 PA II 0-4)cooling air required involves use of thepsychrometric chart. ;!. illustrated by the iHere Q is the required1 flow (-f air (cfin). P' isexample which follows the electric power in waits and Al i thc

diffCrCnic between the entrance temperatureA transmitter requires I kW of power, and of the cooliniz air and the maxinmum allosahIe

102


i1

'I

AMCP 706-120

U $ ARMYPSYCHROME T HIC CHAR I\.,44

u ........ ,

0 / 0

.a .- .. .. .I\L_4

/1 N 0

$ .....T

II

Is-

4"",'7

S I I ,,,

, '':

S.-

If :

911HAP IN @T

F

,JO r0 yAm

't'CWY g ll ? uP~e~

um( 'I 0

FNTNlLP. (D) ToI U P Sol P u io40 o f P oY oeN

of Electronic Apparatus

l e • mmn ~msin ailInmil m Figur 101 Diagram l To Illstat S uini of ProbUUleimi oniCooini tmrli iiiI m n


4Jmbient temperature in the equipment. For This value of cool air delivery comparci wellthe given example one obtainU: with the result of the more detailed cWd-

3.1 X 1000 culation.QJ = = 35.6 cdm(i 50- 63)

HEFERENCES

I. Radio Corp. of Am., Study Report, liec- Pipes A (ool Way to Cool (ihwtr.t ,Ironic Test Set No. 3, Vol. 4; Mechanical Ekcctrunics, 43, 94-100 411970).Considerations, ATE-MTE-L-4, RadioCorp. of Am., Aerospace Systems Div., 4. Study of hTertnoelcctric Coolhng of lE/t -Burlington, Mass. (AD-476 234). tronic Equipment, Final Report

LMS(/HREC A783745, NASA Accession2. U. S. Army Tes; & Evaluation Command, No. N68-15786, Lockheed Mistilcs and

Special Study Report of Hleating and Space Co., Huntsville, Alabama, JanuaryC'ooiing Systertn of Vans and Shelter- 1967.ILclosed Electronics Equipments, U. S. 5. R. E. Franseen. Cooling and lhcating LoadArmy Electronic Proving Ground, Fort Calc'ulation.% for l:,isront•eunial (ontrolHluachuca, Arizona, March 1965 (AD-820 EqaipmnenI Apphcations, U. S. Arm)730). Engineer Research and Devclopmcine

Laboratories, Fort !Ielvoij. Va., 103. . ff. iDutcher, Jr., and M. R. Burke, "Heat September 1965.

I OA


AMCP 706-120

CHAPTER 11

CHEMICAL, BIOLOGICAL. AND RADIOLOGICAL CONSIDERATIONS

11-1 INTRODUCTION agents and r,,diological particulates. ( oilcvAtivcprotection is also provided for vital equip-

The purpose of CbR protection is to ment whose proper functioning could besafeguard personnel and equipment from impaired by dust and the effects of anti-chemical, biological, or radiological warfare materiel agents.ageIIs including radioactive dust. The terni"collective" indicates that protection is af-forded to a large group or area, in contrast to chere prouerton reports tat ondan individual in the open. 'l here are four the collective protection of vehicles, vans. andcategories of CBR protection. shIelters'; and notable am.'ng these arc the

following.

(1) Category A. CDR protection equal tothe standard personnel gas masks wlile elimi- I " and Dcgn .udi ,'Xprrt.•nating the human element (time-to-mask, Rel 5considers the c~j%-c pro-

mask fit, and danger of continuous expo,.ure tection for the AN/TSQide systei .o helivcts.may be disregarded). This includes an air lockto allow shelter entrance or exit. (The The appendix of InC report gives a rCq taiedschemes of collective protection systems for analysis of the shclter system req Iiie for lcl.('atgor A re ilusratd inFig liI.)including a computer program tor (iJR cal-('atcgory A are illustrated in Fig. i11-1.) culations. The body of thc report inludtes

(2) Category 1B. CBR protection equal to plans of CP systems for several shelters.

standard personnel gas masks while eliminat- (b) Ref. 6 i5 a report on , a design studying the human element; no air lock. of collective p.rotection for the M292 :!x-

(3) Category C Only petsonnel gas mask pansible Van.

protection. (c) Ref. 7 considers various approaches

(4) Category D. Shelter space sealed from to adapting collcctive protec:tion cquip-ient

external infiltration and inert as to venti- to the AN/CSM-44 Shelter Systei. In par-lation, ticular. the shelter inside temperatures ,'crc

computed for different collccuon protcctioli

The objective of CBR environmental con- equipment (C1;) systems.

trol for mobile systems is to provide a cleanatmosphere within which personnel can live (d) Ref X ei oils oui a fea.ibilty andind work without special clothing or masks. design study of the appication of collctiveThis requires that purified air be supplied to protection to the various Iy0 cit th0

the protected area of thc vehicle, van. or AN!MSG-4 Antiaircraft l)cfcnse System.

shelter at a pressure high enough to preventthe iufiltration of chemical and biological (e) Ref. 9 reports oi a feasiblhty stndy

rhe collective plotetlton of tanks and sIIwiiUrte rrquulrsg"Chemical Corps boatjJ Repofr 10-50. rield amembly" "" is not considered in this chapter


AMOPC01-120

SAirflow Vol o GPFU

t m Clean AirV Leakage

Protective,1] Entrance

One GPFUOProtected

Area

GPFU CGPFtJ

VTwo GPFUs Protected Area -

Protective

• . Entrance

GPFU Gas-Particulate Filter Unit

Figure I 1-1. Category A Colf!ctive OrotectionI

of the collective protection of the AN/ (U)Rel. 12 reports on test of two modelsMRC-6p 4nd AN/MRC-73 Radio Terminal Set of flightline taxi designed to protect per-Shelters. sonnel being transported in a chenmcal and

biological environment.(f) Ref. 10 is an Interim report on the

development of the M9AI Collective Pro-tector, including a discussion of filter design (3) Modular Collective Protection Equip-problems. mint. Ref. I is. the final report on the

exploratory phase of a program io establish a(2) Test Reports system of modular equipmcnt to provide

collective protection to a variety of vehicles,(a) Ref. I l Is a report on an engineering vans, and shelters. (Two of the concepts of

test of a collective protection unit. Meaure- modular configurtions are shown in Fig.meants of the temperatun rie of the air 11-2.) It was concluded that modular collec-caused by the action of the collective protective protection oquipment should be providedtion equipment and vehcle leakage are of to cover the airflow range of 50 to 600 cfm.particular Interest. The study included concept studies of CPE

11-2


AACP 706-120

Figure 71-.2. Exploded Views of Two Concepts for Modular Conliguratioi'sof Collective Protection Equipment3t

e,}mponenls. Subse:quent r.~ports' 3.t discu'.s trates the design• airflows antI the ia'•,. :lc.tne development of the comiponents. cover. Systemns requuin~arflo irws gi.a.r ct•1 ,.J.i

600 cflm can be ,is.senhibd ro,, vwera:.11-2 GENERAL CONSIDERATIONS OF smaller units.

COLLECTIVE PROTECTION11-2.3 PR ESSU R IZATI ON1 G-2.1 KINDS OF CONTAMINATION

lhe purpose ol overprcss•urc In th lienr-c;Chemical and bacteriological agents can be tectcd cnclosures is to prevent the ini~o\ o~l

employed as a gas, an aerosol, and in the form outside air by ways ot',,tr than through thyof solid particles, collective protection syOWtem. "l'herefor. the

prs.~sure within the ei~closure n~i;t he higlhcrRadioactive particulates cause radiation than the stagnation pressure cat ted 1v wind~

hazards which come predominantly from fall- velocity and/or the speed ,.t the n inxgout settling on roofs and other exposed vehicle. A design value is gur m.ph ol u n i:Lsd

surfaces. Mobile equipment u.sually cannot be wind and veh~icle velocity, which cttrres•[ondlsadequately~protectod by radiological shields to a stagnation pressure of 1.2 n. I1: 1' I1i:bcaumsc of the additional weight required. presstre must be added tm the van ,

pressure. (orrect presstnle is norniidll nuin-n11-2.2 AIRFLOW REQUIREMENTS tained by cortrolling the inflhx ot an• into lti

protected enclosu,'" In some applications tb,,A survey conducted by the Donaldson Co. outflow air is regtdated by anr an,'ti-hackdralt

revealed that in the majority of applications valuc.to mobile systems, airflow between 100 and600 cfm is required'. By taking into account 11-2.4 PERFORMANCEthe elasticity of system designs, four designairfiows are recommended. Fig. c1o3 illus- h, the designing ol a collecttiv p troltem t• ic

Ii 3


AMCP 706-120

600 i

EU

09400-

Z

uj 250U_0

100

0 100 200 300 400 500 600

AIRFLOW RANGE, Cfm

Figure 11-3. Recommended Gas-plarticulate Filter Unir (GPFU)Design Air Flows and Ranges'

system, design goals should be met in the micron and larger. cr 700 jdrticles of 5"Iollowing order of priority: microns and larger. Usually. ambient air is

passed through a coarse filtcr and then11) Performance through a high efficiency filter for particlcs of

0.3-micron size.(2) Reliability

11-3 COLLECTIVE PROTECTION SYSTEM(3) Maintenance COMPONENTS

(4) Weight. size, and power. 11-3.1 INTRODUCTION

11-2.5 CLEAN ROOMS The following basic components are re-t qu-red to provide collective protection for a

Repair shops for delicate electronic equip- mobile enclosure such as a van or shcltcr:ment require clean environments. These con-ditions are obtained by providing laminar air (I) A source of purified air. essentially freeflow directed vertically toward the work of CB agentssurface at a velocity of 100 fpm. Customarystandards for controlled environments are (2) A means of pumping the air into theCla:,s 100,000 per FED-STD 209. which enclosure al a pressur, high enough to preventstipulates 100.000 particles pcr ft"- of 0.5 infiltration of (B agents -

11.4


AMC? 700-120

(3) An air lock to allow entry and exit of located to avoid the excessive pick-up of dustpersonnel without drastic loss of pressure and and, where applicable, engine exhaust and gunto minimize the possibility of contaminating fumes. Dust concentrations are highest atthe enclosure, ground level, and may be two to three orders

of magnitude lower at 8 ft above ground.11-32 AIR INLET PROTECTOR Typical dust concentrations that miay be

encountered are given in Table 1 1-1. AnThe air inlet opening must be protected extensive list of dust coi.centrations that mayagainst a variety of hazards. Particularly sus- b% encountered in nilitury activities i6 givenceptible to adverse effects of the environment in Ref. 15.are the gas-particulate filter units (GPFU) andthe bladed of the blowers. It is the function of 11-3.3 PREFILTERthe air inlet protector to protect this equip-ment against damage from ingestion of solid A prefilter or dust collector should removcor liquid materials. The air inlet p~rotector about 90' of the dust. F-or efficieicy testing.may be provided.with a rain shield and, if'the Standard AM (coarse) Test l)ust is used*.application requires it, a deep fording valve, Simple prefilters consist ol several laycrs ,1which zutomaticaly c'loses and prevents ingus. ixpanded aluninunm shectb. fibrous glas.,. o•xtion of water when the vehicle fords through metal gauze. Cyclone type dust collcctors.deep water. While th. air inlet protector also even though more complex, are lpreIcrred,shields against larger objects such as rocks ind because of continuous perlormance wit. lesstwi,.-bullet proofing is usually not at- maintenance. Fig. 11-5 shows a schematictempted. An example of an air protector is drawing of a dust cyclone. 1ig. ii -6 show,shovn in Fig. 11-4. The air inlet should be typical arrangements using cyclones lr con-

tinuous dust removal. The two arrangementsshown differ in the amount ol dust to which

,/BALLISTIC the main fan propell,.r blades aie subjected.

5 S11-3.4 BLOWERS

A detailed discussion of blowci-s. especiallya conmparison of basic lypte.,. ma>a bI- tound in

5 Ruf. I. Design procedures lor idviitmfying2'. rvquiremcnts ari sele-ting a booster blor

are given Ji Ref. 5. in ,:onjunction with anxanalysis of ('BR proicclion for ' ,vslcii ,iI AIR FLOW I

IA shelters.I ! ( TOTAL

INTERNA blowers should be able to ol-cra' I, or 5(0;1. HOLS Rhr without maintenance or repair, (0I partic-

AVERAGE I AREA ular concern to ilc design cngccer arc the28l.3 SO IN) noise levels gencrated.(TOTAL

AREA N11-3.5 PARTICULATE FILTERS

The purpose of thL particulate fjcter I! to"Filter out solid particle% such as dust. hactcria.

-- -PRESSURE and lhquid droplets having dianecters, down •oTAPALL IM. IN I OTA about 0.3 micton or smailer. l1csign icquprt-

menits are: remnoval of 9)9.7'" l o).,3 nizcr.rm

Figure 11-4. Air Ildet Protector SSupptwd hy AC Spark Mug I)n'.

Il-5


AMCP 706.120

TABLE 11"1*

DUST CONCENTRATIONS FOR DIFFERENT TRANSPORT CONDITIONS

Sampler SmnplerDtman • elght

Vehicle from Above DustVehicle Speed, Vehicle, Ground, Concntrsuon,

Terrain Type mp 1 ft /ft 3

Desert Tracked 20-30 20 5 0.10 -0.20Desert Heavy Tracked 10 20 5 •6 0.05 - 0.10Cros Country Heavy Tracked 10.20 2u- 40 5 0,00)5 - 0.05Gravel Road Heavy Track,-d 10-20 50 6 0.0005 • 0.005

* I sokmi it.i, ker, 1 , wf h su~matruci lii is ,-'tfii w, kct. 16.

particles, and filter awd pr, ,ilter to havy "'bere are plane and cylindrical constructions.dust capacity capable of handling the intak-, The major deficiencice. of these filters atof coarse test dust at a rate of 0.025 g/ft3 1, present are their size. weight, and sensitivity24 hr. During the !service life, the air resis- to malfunction due to vibration.tance of the filters should not increase to alevel where proper functioning of the collec- 11-3.7 FILTER UNITStive protection system is impaired. Typicalparticulate filter material is a glass fiber media The U. S, Army, has standardized a number(MIL.-F-51089. A conventional filter panel of module filter units which include as comn-design is shown in Fig. 11-7. Attention must ponents a prelilter, particulile filler. gisbe paid to the proper scaling at the edges of filter, and an integral blower imit. The chara,.-the filter material. (MIL-E-5 1065 is applicable teristics of some of these units arc listed into the sealant.) For further details of the Table 11-4. An arrangement is shown in Fig,construction of particulate filters, consult 11-9. The aim of present and future develop-Ref. 1"7. A list of existing military particulate mcr.t .'fforts will bc to construct the variousfilters is given in Table 11-2. components of a collective protection system

in module form which ensures saings !r11-3.6 GAS FILTERS maintenance and repair. It wil! then bc

dcsirablk to reduce the nLimber of stan-The gas filter shall be capable of providing dardizcd modu!es to a minimum. For applica-

protection against all gaseous toxic warfare lions with high airflow requirements. a :om)agents. As a measure of this protection, the bination of severa; mod,!cs in parallel mayfilter shall have an operational safe life at its become nccessam,. A sclicmnatic of s-ich arated airflow grcate: than 20 min whcn tested ' concept is shown in i ig. I i-1 0.with a concentration. of 10 mg/liter of phos-gene. The absorbent agent is, e.g., type AS( 11-3.8 CONTROL OF PRESSUREwhetterized charcoal (MIL-C-I3"124A). Onefilter dcsign ,"ypes E(I ard E165) is shown in A men-,, of regul, ing the piessurc is anFig. i i-&. rhe cloth fince media indicated in antibackdrtft valve. It allows air to flow fromFig. I I-8 preciit fine charcoal dust from the inside of the erclosurc to the outside. butescaping. This fine dist is created by attrition not in the zevcrse d~rection. In its simplestdue to vibrations in the installations. Other form, as illustrated in Fig. I -i 1. the valvecritical components of the filter construction consis:s of a hing;.d plate which lifts un Whenarc gaskets and sealants. The design of gas the internal prcsurc works against its w'igh:.filters is covcted in Refs. I and 6. Table 1 -3 The adjustable weight position delcrmninc thegives a list of presently available gas filters, pressure drop across the vaive. 'This #'onstlh-

II-6


DIRTY AIR IN rmn; w a wontro loop. .ara m-fs beczereacd io avotd unstable mods i'ttchCould 1i!ad to pre'ssure -yclng annoying to theshelter ocCupWnu3.

11-3.9 CONTROLS

The controis reor red for collective protec-.tion sytern-• Comprise switches, indicator,cuvr.ut breakers, and warning dricc-s Inpafticular, some shelter systems have hothvrkal and audible alarm indicators wrhid alc-.

S,,he operator if the preure in the enclosuredrops Wlow the danger point. A mntnal)operated switch serves to turn off the audi'9alarm, w.ich autoatka.fy resets for a next

"I ttiu. One component of the control pWt is.an elapsed tume meter which indicates imainte-

Sjnance interval requirements of the system.

11-3M0 PROTECTIVE ENTRANCES

*-" ,A protective entrance is used to pro-'ide a* .~ mewns of safe entry and exit of pemsnncl into

- ".. the protectie in'titV of thE protected AM

" " EXK. UST durir. entry and exit The pressure of theProtective entrance it =nmaited at a 1vhW= than atoVmoq prssur but lovmrthan the ptemw muk the shnlter Thispvnts pol e corraUinnated &r in theprotective entra•te from penetrating into theshelter. In the test ytem, the prote-tive

CLEAN AIR entrznc is nedther' htaWe not cocied.

OUT Ease ad rapidity of i.- "lation we ofpaam unt fimportc wiL protective en-trances -'m ction of protecme entrancefor v- I , .IJ s ar f a , ortable shelters is offabric, such as butyl coated nylon, and z

• 7 .5. S -5 . -fta xSe tor suppt 1 frame. The pa"P doors am,STube C ydm Pf P *, unally waaled 5y means of spinploaded

Tube ~ "~'~4' nteewdockl flaps or 1ky *ipers. A Oriallwindow with -bickout catwla is pmroided.

tion h! vey s-cepuibt to vikvtkm. but the For moev detas ee 1ef. 1. Proctau fordashpot helps to dampen them. Other fons decontumntion of Pmome ad O materiof rePtti V*es coneW of motorized eutet the pott eftntraeam Mrelouver or ades atuated by prew treat .in the rCem operator maintenanceswitches. Pre re sensors and .=trto loop n mt .

11-7


OUTLET ORIFKcE

I ----- DUST

S....EXHAUST

AIR PRIMARY

* FLOW FLOW

"-/MAIN FAN -cDUST COLLECTOR

(A) &,at CofJtr Oo•imsttm

DUST EXHAUST- OUTLET ORIFICEBLOWER

___ P o LomW

S- " - EXHAUS T

DUST COLLECTOR

[mA ? FAN

~ 1 1~Cyd0' ArrVatpmmr hw Cwmnjm~.o Diat RwrMW

"•. : I-I4


META ENDPLASTISOL

FILTER

MEDIA

CORRUOATEDSPACERS

SCREEN

SP`ONGCR J8 R

METAL SIDECHANNEL

Figure 11 -7. Typical Panel-type Particulate Filter Construction'

11-4 INSTALLATION AND MOUNTING some instances filters must be mounted JnsJdcthe van or shelter. If radiation p-tcction i-,

Sore. of the veidcles, vans, and shelteis required, internal filter installations will re-that require collective protection specify that quire a radiation shield.the protective filter be mounted inside theprotected shelter, while others specify that it The internal and external mounting of thebe mounted outside. The internal application filter require different designs to protectis usually specified for combat v.hicles, such personnel within the shelter from CB agentas the Main Battle Tank and Mechanized containination. When the unit is mountedInfantry Combat Vehicle, to provide prot-c- within the protected enclosure, the main fantion of the filter from battle damage. Vehi- or air supply i6 mounted downstream fromdes, vans, and shelters with logistic missions the filters so that thw air is pulled through thegenerally do not require that the filter be r11ten. This provides a pressure within themounted within the protected area, both filter housing lower than that within thebecause there is no need for Protecting it and surrounding protected shelter. Thus, any leak-because internal space is Um.ted. In addition, age in the filt-r housing results in clean ai-the noLse generated by the fans would be from the enclosure leaking into the filterobjectionable to the usage of some shelters. In housirg. For external mounting, the filler is

I I-Q

.4


iCk:lP 706G-120

TABLE 11-2

ý:XISTING PARTICULATE FILTERS FOR COLLECTIVE PROTECTION SYSTEMS"

Rated Overall Maximumfilter No. Flow, Dimensions, Air Resistance.

dm in. In, H1O

MIA1 150 24 x 24 x 3-1/16 1.0M1; 12 7 x 5-1/2 x 1-7/8 0.7,1119 20 7 x 5.1/2 x 4-1/8 0.94

MQ24 150 22 x 21 x 2 1.0M22 400 21-3/4 x 16 x 9 1.1C18IR 600 24 x 24 x 5-7/8 1.25C19R1 1,200 24x24k 11 1.25C 20R 1 5,000 48 x 48 x 11 1.25C3OR1 2,500 24 x 46-1/2 x 11 1.0'47 2,400 43 x 31-1/2 x 6 2.0

XM36** 400 24-3/4 x 17-3/4 x 6 0.79XM37"° 250 24x 14x4 0.58

"List provided by Physical Protection Lab. Defens( Development and Engineering Laboratories.Edgewood Arsenal, MSarylnd.

10Thpe clais•fication anticipated by end of IQFY7l.

TABLE 11-3

EXISTING GAS FILTERS FOR COLLECTIVE PROTECTION SYSTEMS*10 mg/liter

Rated Overall Air PholegF. er No. Flow, Dimensons, Resistnee, Gas Ufe,

cfm In. in. H2 0 mlh

M18 10 5-5/8 dia. x 9-1/4 1.4 31

M1?AI 12 5-7/8 x 6-15/16 x 3 4.2 28

C22R1(1) 600 25-1/2 x 25-1/2 x 29-1/4 125 48

C32R1 (2) 1,200 25-1/2 x 25-1/2 x 51-5/8 1.50 48

C'29R1 (3) 2,500 25-1/2 x 48 x 51-1/2 1.50 48

C23R 1 (4) 5,000 48 x 48 x 30-3/4 1.50 48

M21 100 22-1/2 x 21 x 2-11/16 2.3 33

M1, 150 24 x 24 x 2-11/1I 4.5 46

M23 150 22x21 x2 3.6 22

C4S 220 24 x 43 x 1.1/4 2.1 18.5

XM34(5) 400 24-3/4 x 12-3/4 x 12 3.6 22.3

XM36(5) 250 28 x 14 x 7 2.7 31

(11 Assembly consisting of 10 CIO modules

(2) Assembly consisting of 10 C31 modulas

(3) Assombly comisting of 10 C21 modules

(4) Assembly consisting of 20 C21 modules

(5) Typo classification anticipeted by end of 1OFY71

"List Premided by Physlcal Prot-tion Lab, Defense Dcvdlopment and Engineering Labortort.

Edgewood irsenal, Maxyland.

11-10


AMCP 706-120

8

1. Gasket2. Outlet Channel3. Corrugated Saces4. Cloth F;nes Medo5. Wnlet Channel6. Perforated Metal7. Charcoal8. Ho'Lsing

Figure 1 18. Typical Latest-design Gas Filter'

!!'-I!I


AMCP 70-5 -120

E

SX Nz,, N" ;

"" X X N X X N 04

D .

cc I ccit

aFa

4�•I ME

11-12


AMCP 706-120

PURIFIED AIR OUTLET

G AS T'lL TFR S

-I~:LTER

iblltET SC REEN PARTICULATE FILTER

7> LOE

Figure 11-9. Air Purification Unit' I

FigureM 777.PrlllArnemn fTre PU

GAS FILTER


AMCP 706-120

I-I I -~i1j,

Fiur I I-1. An/I.da t ale

11-14


wrpud- t ,nL tacisaarcd IVy nS Mv ssnw Typial nranpnwnts of Gift %ynenv4 artka O w VPM knas-rd nwA n Innv the shovmwnshcuutically inft. 11-1 IA 2 and I11-1 3

mitr- thus PgnvwvMstr the filter howus~n As as true f or many Military air-conditoningshow the ainbinn air, Any leakage in the amstwailtm, CB Protective equipmeTnt May behcnntrtg will retuft in air 1eakuig out, rathier mounted on trailers for Storage, rrarnpen.tt~han the contaminated air eaking into tht and operation lItthe traler is used for remotetNuning and postibly e-t~erin$ the %helter, mouriving, it as ncccsaary to rL-m electricalihnesThe modularr approach facilitates apilication and air ducts between the conditioned spaceof thc unit to either push-througth or pull- and the remote CII protection cnit. Fig. 11- 14through configuration. :Eustrutcs a remote m~ouning.

IN

Fig". I., 1- 2.rwm PEAhrD bi 440ho&~4

.* a ,-tdS IH, wt, o~fie Polctm orj Apld cknc Mrsin2St N71

4"0 NM 291aAM16 A 0)

M~~~~~t~V I po m'.w Re.E'-D

645Mq 4.**16 Get D*0- - -m-fl

Reotw.' Repo N. 211, 001i501 Syste 10D. ~ Iego oigRi


I I ,

Wit Bose Blwr

-- -

Report,~~~ Amr. Ai Fite Co. In. Loui- A of "W tr hnitr"is o

, I . . . f... . . I

S07) v e i.ficle -

L I f

7.ur 11vjycf('i~n-13.Sematg-ic Drrawin9o oletv PoetonSse

Byn,&Iet. Protection for A(ýG,14 ~tm. pa. FuabllertondOsnSt), fao..Dcebr 1 964(-

7.11- b.iof colngf*a-n-C.0 •i-

Prote', t D. fovrsK AVG1..W st1, n l.S.seJ. XFe.-a4ili' d 1-si2.Studhy. forcrf 'om,-

507 .1eices6


MAI

COI4PARTMENT

AN/GS ~I

FILE

C340TITE-

~-PRESSURE CON7iTHL HOSE

SUPPORTUNIT ITAKE (COVERED)

Figure /V 14. Schematic Drawing of Shelter Collectve Protection Sysem WithAir Conditioner and Filter Unit Mounted on Trailer"'

tin %mv-tiffm Equipownt fior the 10~. N. P. Oldson and R_ J. Zablodi1. kcAV'tLS(4 System. Study Report FD liiw Frvtecruo !ksign and Ikrrdopment.6Z-75 ifugbes Aircraft Company. Fulier-. TechilaI Note N-783. V S. %avai Civiton. C'alif. 15 Mmrd 1962 (AD-2174 Enjitecring Lab. Porn Hucncne. Calif-.245) Noimbcr 1Q65 (AD-625 402.'1

9. 1-anibility S~ind) of Coufkcritr PWroteism 11. W, (iooicy. kt and4 R A McCullough.for Radio TrMninal Set A VAMC(-6w 1. ) Report for Egi~nrerng Trst of Colfr itand Radio Termital Sei A.'AMRC--i. Pro tertfor L'nif !or ("Mbat 1Vdzwkl.

flughes Aimr-aft Company, Futkrton. .ikr-hant.:rd 1npsntrs VJ1 701 Repo"iCatlifrmnia. Fcbniay 19Mvr I APh4Vl 15Z). D)l'GR E546. fDugway Provirng Ground.

11-17


iugway. lUtah. Matze 1961t (AD)482' Kesemb rml titutctý Lbe-pt. of AutornothvResearch. San Antoniio. Texa. 26 Oct.1960 (ADA721 67f)).

12~. P. W. Kloii. resyjs of the Modifled Chemi-cat and MloAoracaI-1ightfine Taxis, Re- 17. Design and Dkielopment of a Callectireport ADIC-TR.68-4. Anntrunent Devtlop- ii'uteticn System fcw the Mains Ilaftimoa~ft andl Test Center. EgIin Av Force Tank, Donaldson Co.. Inc.. Minneapolis.Raw. Florida. August 1968 4AD-840 M~inn.. Jan. 1964 fA1).29 17!).276).

18. Univ~. of Pittsburgh Asny Mataeli Re&33. J. It. Scott, (04lectire faection for Staff, lkivloptnenr of CoIlectliv Ptuter

Vehicle-s. Vans and Shelteps, Report No tnon for Tentage and field Shelters,3, Do~naldson Co., inc. Mi-.apcgis. Technical tinfornudar Report 2-4Minn.. June 1968 (AI).83? 997). University of Pittsburgh, Pa.. April !944

(AI)444 298).14. J. Hi. Scott. Collectire P'oeec: ion for

Vehicles, Va~n.; and Sh~eke, Report No. 19. Feasibdit) Studsy. Crilkcm te W~tic tio~n4. Wrialison Co.. Inc.. Stinneqpolii Equipment for R7'L MITE. andMinn.. Septembe.-1968 (AD4J44 172). ANIGS.4I-44 Shelter3. Report

FR-64-1 1-7. Hughes Aircraft (ompany.15. Hurnan Enjoteft Laboratwkis Stan- Ground Systems. Fullerton. Cahto-.nia. 5

dud S-2-64A. lluvon Fectors Engineer- Feb. 1964 (AD-431 306).ing Desig Standaird for Vehide Figfi~ngCompartments. Aberdeen iProving 20. .1. C. Groff. Dcidiopmeni: of C~ulleclnveGround. MdL, June 1968. wtlecrion,"C"imae Control Support Unit

and Col/ectire Protecfon Systemn for16. C. A. Hafer. and D. J. Skinrn, Definifion ANIGSS-l Radar Su "tillance Cewral.

of the Dust Ern*ornmnt for Phuposrs of Summiary R~eport FR4A6-I 1-27. HiughecsGas Turbine Ingeto Suas.FweI Aircraft Co.. Fullerton. Calif.. Decembe-rReport No. SWAR!-E1E-387, Southwest 1967 (AD477 5 121).


APPENDIX A

FtNDAMENTALS

A-1 THE PSYCHROMETRIC CHART A-2 OVERALL HEAT TRAESFER COEF-FICIENT

The interr-lationships between the ihermo-dyt~-� of tlx mixture of air 3nd The over.All heat transetr coefficient. Cr

*iter vapor air represented in a voncise forn Ujacwr. of a wzal c.-r be derivcd from theon the psychrometric chart. The U.S. Army zxpresionPsyebronetric Chan. Fig A-I. gives the fol-lowi•ng quantities*: U

U - .IBtu/IFh-f4&F) (A-I)(I Dr)- Bulb Temperature. OF fR +-

(2) Wet Bulb Temperawc, OF

where XR represents the sum of the thernml(3) Enthalpy. Btu par pu~nd of dry air. resistances of all tayts of material (includin$

(The chart gives the enthpy in the ak and its air spaces) composing the %-il. and - and foassociated moisture, relative % dry air at P, are the ai fim conductnces at the inner andexpressed as Btu per pounduf dtyý air.) outer surfaces. respectivey. Typical values of

film condu-cancts ave (Ref. 4. Ch. 26):(4) Relatire tuminfdty2

(5) Humidity Ratio. rainm or pounds ofmoisture per pound of dry air. (The dry bulb 4, = 4 Btuf(hr-ft,-F). fbr an outside aixtemperature and the huwidity ratio from the velocity of 715 mphlinear orthogonal coordinate stem of thepsychrowhtric chart.) = 6 Otuf(hr-ftl-'PF), for an .lside ai

velocity of 1$ mph.(61 Specific VoPri,tw. cubic feet per pound

of dry ais With the snmaller value of ,. wc have

(7) EffectS€e 7"emrnire (Ith'. °F U !____

18 0.73;f any two of the above quantities atn

S-p,,citied. all the other quantities can be fradfrom the psychromctric chart. In parfictlau. and ws!h the 6rr value of f. w%*-Twofor a change between given initial and fina]conditions, the amount of cncftt invoteed is ! 1given by the dilference in the conesponding .R ÷ t,7enthalpiC&

Thus. considering tkit 41he contrilwutlon of X8is donlnantC a i-McUical formula fr* t)Tical

4se (409MY FMf &fiutiom. orumwsde desig cv.Wiition is

S~A-i

3m m


U S AWYVPSYCHROMETRIC CHART

UU.L" tgt96

6@60"If oXisf

aý

-~if

A-2K


LIen on cwfaglue MU of each of th7~#. BMuthr-ft 2'.F) (A-2) cmoets in a system. To fttmiim tht

provided~~~o~~oest R ateadrc jito .CMOM n tOw system. Asmming that

The aftruW owc=Hl heat turanfcr coefficient O O tfwoa mualyk pednof ani enck)OSf can be deeandwt a tes fadtrl b thetw* ca wsymstemt pefon sefir,

chamber in which it is poukbl to control the fICIwgy fo h ytmtojfm01ýtempetatume The van, shelter or other en- fystaft isth WOWS ofa the faLOWe rate of al thckosmn to be tested is placed insie the test Sytmithsuofheagrrtsofnischamber. Then a beat source wthich Wene1tes COPS~s Thmheat at a kstown rate is jpLavd lmide theecadosre so that best is ws4WLbtdunifo y wwonnwithin it When beqilboun mjditios am TR (A-4)

etdablished; he UIfcior is given by rMoiniiUFaflur Rates

A f SmBtuIWh.tF) (A-3) AM example of a rditbilty anaysis for threeA V -Alternative enVnirnmental contro *1ystemi sOm ih Appendix 0) of -&E 1. Adtma

where ~infmOt~oe on the aineamnent of systemnftibility cmn be found in- Re&s.Zand 3. Ref.

A = total nurface ame of endosur, Wt 4 provides failureate data on many comn-P~OflCtX Of Miltary liartwaz

q - rate at which bcat is generated ieddethe enclome, fttu/h Reliablty R is 6tfioed by the fanrnla

tj a vera temperature iNsde the R =exp l-0rIVTOF1 (A-5)enclosur, *F

to =averag tempe eouztld& dueenclour, *F t nlsfl ime

Althouho this procedure does not accurate- AITOF t~m-ewe-ahly amulate the out&oo conditions (mainlythe wind velocity and radiation Wcons) the The reliability of a uinit with a-pvtn MTIFv~walu btsined is suita" for applications is the pwobabfty that the wait wil opertewithin the scope of this hvidbook. Without fafl*e for ý. period t. Wahues of

MTDF can be established far a tompom~t by43 MEASUES OF RELIMIUtY records of its perfomance while in uwe or by

miabty emoWmt"q -x F-- a pmveA meweir of the refiabilty of a de7lce bs WB~F. the rlixbfty caecreues if the "ision

the mea~n-da-between.-faiw" (MTSF). It tkfe is Lncremed.

F1. C A. Iiagher& Coikedre Phfeedmc o for 2- Asfro Kelhabty CWP.. r&&t~sy Ans-aGom*W I*IE S*thewom Vol. It. Re"or menf Iimdook. 16 July 1961 -6 Jaw-No. 3MO Utton Svftem, b%.~. Mimi-, mty 1962.*dg WMASO SttI-


Tthi zrqpt is an adute rvexeamination ofobtneci ntedegd~pthe whole Pmst of PuhiUidW techswk snent. and production of hardware forof rellabilty me"Wts of dectroldc amd variouis submarine, ship, aircraft, gu~edc

t~ectronchankg ysktm.*missie. satellite, and vuduprequipment pspMOM MitarY c~ntrwtt

3. Rd~siJty Documeni LMYC 447458, and ohms participating in the propasnLockheed Missl and Symc Company, wflribute failur iz'te daM from infovrma-Sui~ayvale C&. 6 June 1962z. tion btfti dii3CiF psoPIIDS Th .t -s

nitte~da"ame =vise puykas newThis document is a conrnpoeu~ive ptesen- ifts~ mm as bta

r ~tation of tecdinkues to~ he utilized in the abourt 124 contributing smrces (noneasseurnnt Of system, c ponziit MWd put Mmdeaid by rame) who supply datb Inreizbility considration examutered dui- two cateories: electrical and electronicing de~ign, nm~acttwoe and test. L-~eit and nvchaicaL. hydrauli,

4. Bureu of Naval We~pons (SuWeps), F&M. coimpmfeftL Each Mmbr rate presented isure Rate Dtha Handbookc. (FARAPA) W~nfified as to sou=c and the data fromSP63-470. which it wa coinpined.0

L PEAPA is a 13up*-snousot~id smrice-ý Ay~m0o

Fto provide reliabiniy design data to pifmeVA

A44


r.

APP4IX I

DES1I4 CRITEIA

1-1 CLIMATIC DEQN CRITERIA tmpea , huidity d solrtalatio forthe Intewd•_e cn' --t Cli atic ctO ,

The poliy reprding climatic design criteoi which ame used in most *pplicatioa, arefor Army mteriel is Siven in Ref. J: quoted in the • ag-phs VA cfcow.

"1-2. Poficy. a. ClImatic Omidetdom COateO 1. iUVWM "P tcnc of reM-wig be included in RO)TE IRem", ative hmidifty above 95 percent iv owe&la'Development; T_•.+•+-d E alutlonl of tion with temperature nely comtant atAMnY Materid to provd eafe and effc- 75F occur for periods of a day or morm"tie materiel for ar'e of b use(opertime and Storage and transit). Tlie Gtl• 2 YMMer. "Four contnuoWAntarctic cdnlnent i1 excluded from hours with an ambient tempeatur• (4-6 ft

is an arta of intended me. aboe the ground) of 9VF, a maximumb. Stmndr genea purpose materiel pround sufa tempersat of 130WF, maxi-will be dsýiMd for safe and efective mum soa radiation (horizontai rfce)ý, at aume in the intermediate and wet climatic rate of 360 Btu/fk2/hr for not more than 4-hr.categories (Categoies 1,2,5, and 6 de- a widpecd ea ttan S kroft wncament withfi6d in Chapter 2). Materiel for ue in the igh tepperatures, and rMath humidityothetr climatic cateries will be priovied of 74 percemt ,*oncunvt %wth the hihby deOphWn (1) standard materiel tempahtmr."cap"bl of suh ms; (2) specWa materielexluivly for such use; or (3) modifi- Catreoy S. itemrAkrf "t*hror "aFourcation kits which adapt new stAdd hours with an anbiem Ai termorAture (4-6 ftmtei or pevioM y typeý ied above the pound) above l0S•F with an

standard mteiel. The appoach chosen extreme tempeature of I IOeF for not momwill be that which provide. satietary than I hr. a maximum pound surface tempr-Sin-the mo e mn , &atufe of 130(fF. solr radiiation (hrizwntalSextent of deployment in surface) at a rate of 360 tuftfl/hr for not

h of intended-toe, the devlop more than 4 hr, and a wimdpeed between 5mert state of the aM, and the time and 10 knotb during pei with temnpatmrerequired for development. For muanpk, abo•e lOVF. For elevatis of 3,.0ý ft toif catain matniel h to be Weed otly in '0- ft, the goimud =rf=e t#V4%Wextreme cold conditio, the secmW and wind remain the saim. but avntappoach aboe would be aected in temperatu, decrease rF P"' I X ft awdSMOO caof radatiz i• • c tf 4

Btulft2 ~ *per 1,000 ft."MR I defne the varim cfimatk cate-

pores by pecifying t0, e codtion of air and Catery 6. Intrcmwtde cok. "ft con-*ater taerift, SCAo• adiasom, water tinumo hous with an a3dent ir tempers-vpor, pftclphatOM i ow sad Was pbmont- t 4-6ft abovetue $Lewd) of -2rlF, a

mad and dut.Th aLa condtlo of *Winseed lea than 10 knof.a, nebLe solW

3.


rMdI2tiorn Qmkwxntal naurae), arid humidity TABLE 0-1teisdlg tou saumi Inrquf MUM1AV ALLOWABLE 0OOENUM ATMSI OF

dspcweed gowe than TO lzmts ma beCRO CO0waiodmzje with tcrnpe"tumm of 2*.

&~2 ALAVOMALE CAIRWP MMXIDE _0K ~CONGENMTRATO 20 2

40= 0.12in~ notdnce with Ref. 2. cadbo monex- I mlin 0.0

id& concntrstions sould not eXCeed the 3 hn 0sve V3IIWS ror the interval indicated in Smi. &02

table aim. io,~mn TbeB2 ht ontno m

The maximum notm leve permitted in pezKM-t*VCson (nonclecticsily Aide) coMi-pua+=pied space of equipmet t munication of infor~mationii s a "eslm meae.developed, or procmed by th-, Army quninmct the steady uiori levels du)&ad not

MAterie Comnand arnd the fteia q S7iWw cicwid thwovepen ini Table 3s-3. Noise redusc-!ncnts for detemidning coiifomumwe to the Ow11 may not be aceonPiided by pecifying

peswtte eeib an estublished by HEL wmandtc1y wse of mw protectmv &eMMe tx-St.~ad S-2-64/0. This stuadanl specifies Cept tgo avoid pmeti*.Ue cost or dcpdadtkm

thw eqiwpment for apautbw u orCi of systm effectiveaem (as determied by thewwoualm ab S notmp~vpersmp ocudag activity).

tIAXMtTWY STAtE NOU WLML FOR

,,. CwwnwW FteQwe ASA Z24.10-ISW

379 S53 12075 Ido M1It

150 -3w 212 Too3Ma -M as04 101am0 I=~O 860 93

1200 -2400 1700 so2400 -4M0 3w0 so

Ow -rA Lbm*IP cowr FOOMY. Nill. Lod*."a It do

44 - 07 63 Ito6 7 - 1-7 12S 114

fi - 3S0 260 to?* ~ ~6 M-?0006

m0- 140 100911400-2M1 (06

2600-510040001- ~~fi '3ilmob0U

5-2


MAXMUM STEADY STATE MMO*LEVEI L FOR NQNELECTAICALLY AftXD

A. Cw~merciaIFreqmmsa&SA Z24.010.9W6

37.6- 75 611 7975- ISO 106 73150 -300 212 Go

600 - 1200 O5w6120M - 240C 1700 62400 -4800 340D 56

B. Puvfwr~dfWwk ~ASA S:.IAI-19

44 -6W 63 7767 -175 125 72

175 - 30 230 6750 -70 600s 63

700 - 1400 1000 611W -2W2000 so

560 - 11200 8007

Ref. 4 *a~ a pwtactca example of a stusdy speech. SRIL is defined as the av' :W (into detenidn how much acowtical mateal is &~) of the musking nose's souyW krebmvquized in a shelter to comply with the in Wene octave bands: 600 to 1200.reqwrements of Table 9-3A. 12.00 to 2400, and 2400 to 800 Heesta

(HI). Sometimes speech intesfesewc canbe ftedicted bettter by abc averanft in

S4 EFFECT OF NOISE ONi VERBAL COM- the 30"M60 Hr bend if it is 10 dR orNANW THMmore fude~r than the 600-1200 lit ad.

The SRIL cannot be twed if the madtIgRobse has interns I l-ftquncY compo-

The effect of noim on vesbs coimmici- m I bbc sod, isk level wbklOm cani be expressed in teruw of the 5Pweewi d nistareiabe IdoIweIution (7Inteffefauc Level. In woanewith Ret. 2: percenst wonosylaei woeui Wint

va"bay) (at dksetl e"41W

11% h ee atederentce Leve (I~L) At "dmi SIL wkkthon Up m~wem isdescebes how eflect~vey raise mask shown in FuRom 11w] .-

'.3


a4UtD

x

1 5678 1 0 2

Ditncf

4..'.Efw fAi, ewts, n oc

L"o won-aon5aeoto

I HEL Stndard 5-A HunmF stm nMd, Im16 ftM 07)

wwxkV~4# S.W Fiand ek84. Equip-' 5fPl .Spwati an. Stndrd Assm ASLebmatoOL",LAvel rovif Gmnd. theAm~ps Cow ,~c ofN oieadOhrSw

I. MEL 70-38. RS-1-639, Devloment Abest 4 lH i~zd rNu teiLed fuaitor A ofn Mwt as *1 for Equip- & AgeriasIn Sandad Am1/ &I. ASAhClinwkCsdos My16.Nt U.S. ArmyHmnEgwyi .- 16.Afm Frruenax foreci

Labntoift Abdm wvb Gw-mi A oitoical mawerdents ASA.in Gron

Wd., Juee, 1965. York, NeYok .Y.


Af, ENDIX CDESIGN PROCEDURES

C-1 DERMINATICN OF ENVIROIMEN- which fan driven air s used as the trnsferTAL CONTROL REQUIREMENTS nwedia. An estinule of thT p1•sure low in the

cd.cu~ating stwern will peirrmt determinationof the static pressure which must be main

C-1. OUTLINE OF PROCEDURE tained at the eitrance to the ystem. Factors

to be considered in this estimate include .While it is outwide the scope of this ductmg loss, shelter distribution loss. sheriter

itandbook to give a tho •ugh accrtunt of the leakage. and heating/cooing equipment to%&Wculatbn of ewvirotunental control requi- Determine charctetistics of a fan required tw

*-N tsr infomiation on the subject is overcome the premwur loss while mantainingi mnckf.d in this Appendix. This paragraph the required air flow rat.•€/ an oufte of the procedure includingcmiikratiom of factors whiuh affect theo oaf tC-1.2 LATENT HEAT LOAD CONSIDERA-de an envinrnental control system, TIONSfbawl4 paztapbs eive prCtical examplesof deftn kidaftios. The lItent k-at load is of interest only

during the portion of the environmenta)ThM foClowing JS an outliM of a pxocedure control op m.tiov when coolinS is required.

tog deterrning the perorrmance require- The principal sources of latent heat load in amcitin In gng an environmental control shelter are: moisture from personnel respira-systzm fr• a shelter. tion and perspiration, mosture :tom materials

within the "helter, risture from processe(I) Caculate shelter wall heat transmis- (e.g.. photogaphic processing and laboratory

tion. Thi wil require assumptions for the baths) within the shelter, and moisture ad-following pararetenrs: georaphic Iocations, mitted with outside air used for ventilation.shelter oarntation, time of day, wind velo,.ityand drwtion, outside temnprattre, and de- Athough an estimate may be n'mad of theSired elter temperatur latent heat load before selecting air condition-

ing equipment for shelter environmental con-(2) Calcuate heat transfer through walls of troL. there is Little o;.e can do to accommc-

air duac which are external to the "elter. date this load. The packaged air conditionersof the type used for portable shelters have the

(3) Summarize total hest load6. The loads capability of removing a fixed ratio of mois-cal~cuted in Items (I) wd (2) am to be tur- to heat (latent heat/sensible heat) in aadded to the personnel heat loads and the given operating statt. The latent twat factor.heat loads genewated by eqmuipsent within the or ratio of latent heat to sensible heatshelter. The m tmtion of the heat loa4s removed by the equipment, varie from 0.15knkatea the mizantity of heat which must be to 0.35. E-'aporatofr coil design affects thistenioved fro~ti the sltter, ratio in a ptedictable manner; the longer the

air is in contact with the coofin coil surfaces.(4) Dot, tmine the prawu loss charaeteris- the greater the quantity of molst,*e removed

tiks in Wa er tramntid controW sytem in ficm the Wir. Thus. low at vrlocities tlhoult

C-I


4

I

deep coih te:ad to incr"aW monsturx renova. t; tVi•,n Redu.cd air denst•, iak highwhk.h is equivalen to removal of haten! hat alitudeas On .ffc,.t of lowrnng the heat

transfer rate whilde the motor is in opcration.the example givcn in par. C4. Appendix C, thus sugpsling derating the pot.r output of

indicates Low to take the lat•nt heat t-md into the motor Motorm should be der-atcd b) aa•zount when sdkcting an ,ir candityer. factor approximately k-qual to the au denszty

ratio. For ex+ampie t? dcnmty of air " (K0iC-1.3 ENVIRONMENTAL REQUIRE- It is 0.83 times that at wa lr.el Iherrdore. a

MENTS FOR EQUIPMENT AND motor with a rmtiry of 10 hp at sea lkwi forACTIVITIES operation at 5.000 ft shouh; be rated at abewt

8.3 hp.

In aMition to z;mm.odating persopei8elpthe environmental coptrol system must ac- (2) h-ni (ontlaf-} to intuition. the de-commodate equipmernt and processes con- igr•.r •.an expect fans dnven by alternatngducted in the controUled space. Conditions of current motors to provide approximately thetemptrature and humidity which are rer-ired smm: performance (in .fm) at high altitudes asýfor typical op mationu are listed in Table C-|. r I sea level.

C-1.4 PE•FORMMNCE VARIATION WITH (3; Air-cooled Cundemers Where the airALTITUDE cooled condenser 1s equipped with a motor-

driven fan to move the ar; across !he wods. the

The effec-t of altitude on environmental fo!Iowivq would be the situation at high

control systems for mobile shelters should altitud A equal volumb of au *ifl moveover the cods at any alutudr. but that at theconsidered when designing the installation, higher altitude w•Il be lIs• dens•e: therefore

Although specific information is s',Jdom pub- thie mass r o, rlat w s b oe-er and the beat

lished concerning equipment rating, at high thass flo ratc is lw and th beat

altitudes, application of engineering judgment transfer rate will be reduced by a factoiwlluenable the desio r to n eg anudstimate approxinmtely equivalent to the air densitywilenable the des•grucr to make an estimate ratio. The condenser must be derated by this

of the adequacy of his design. Ref. I indicates ratio.

how the high altitude performance of air-

conditioning units can be estimated Ex-amples of the effect of altitude on the (4) !!eating Coids. The derating reqwucd asperformance on some confimon components previously noted for air-cooled contlenser.of environmental control -sytems are: -ay aLho be applied to those heating devics

TABLE C-1

T1W•RATURE AND HUMWDITY REOUkAEMEAT' FOR TYPICAL EQUIPMENTAND ACT1VITIES

Equoownt C# At~ifty (0ery Bulb), *F Hudty

1. Electi 4 swiwnmt. cnpciers t_&8O 20-65

2. PMotoqapmek i ug uixd ptentlnh 10-0 45-50

3. rFp& burch. seftia or eectronic 65-80 20+66

4. fpair berth. vinI m~tdnwas 72-76 "

5. cO*tkmi Iiormto5y0 2065

02


whtch depend upon o.omttion u. formd air 15 cfm per person, when moderately hcavy,fl--- for heat tr'nsfc." . The Wa of ficai smoking is anticipated.i.mnsfri by radiation is condicred to beindependent of air dcns;ty vanatiorn. By paying close attention to thew three

faetoon outside design ambient. inside designC-2 CALCULATION OF COOLING RE temperature. and ventilation air require-

QUIREMENTS ments tMe system designer can choose an air

conditioner that ts adequate but not over-the following example of the proocvdure sized.

for calculating cooling leads was taken from

Ret 2. It seres to illustrate the req',ired B. Sample Problemsteps, A morm dev.aied desciption of designcalcutlations for both heating and coohng To illustrate the selection procedure therequirerwnts is given in another example, in following example is used. Assume that anpar. C4. Appendix 1L. S141 shelter (light frame construction) ts to

house two people and electrical equpmentA. Design Conditions* having a 3.16 kW rating. The shelter is to be

located at 40 deg North latitude and thc time

1. Outside Design Ambient Tempera- for the combined maximum heat gmans fromLure. Army Regulation AR 70-38 establishes the various sources is assumed to be 2 PM.the maximum design ambient condition of August 24. Fig. C-I shows the dimensions and125 F DB. location of the shelter.

2. Inside Dtsgn Temperature. When C. Solutionaselecting an inside design temperature, it mumtfirst be deterrmned whether fth controlling The following symbols are used in thefactor is persotnl or equipmentL Once the calculations.controlling factor is determined, the inside specific heat of air at con-design tempmiau should be based on the stant pressurc 0 24 Btumaximum allowable-. Fo- photographic pro- (tbD.F)cesses. it may be 7(V-730 F. For personnel, thetemt erature may be 70V-80*F and for dcc- (1)tronic applicatio s, &0"!0 0WF.

When designing for extreme outsidrambient conditions, it is iuually desirable toraiw the in-4. design temperature not oo.y (4 ( )to reduce the amoust of coolUg required. butalso to make it wore comfortable for pcrmn-7hel moving in and out of the shelter Al5-epree difference is recornwnided. (3)

3. Ventilation Air. The third design TOP VIEW 5141 SHELTER

factor is the amount of ventilation air to be Maws -nso' : 142 " L, 61 Ir.. I, '..3

brought into the system. F.xcess ventilation Z1av- Color Dw-k Ore=air needlesy inceAe either the sensiblecooling load. the Watent cooling load or both A R of !.4•eicr± 0.)5 i-'.-•- -'

Thev r ommeraded venn~iation ai is

"Wtt~i mmcv c$•et, tbc Teu o thiS ADr-675lx wk

11mm Re apphirg t he MA#A5m ta Rtf4 F19wre C- . ft n View of S4 Ihr iter

C-3


L - latent heat of vaporizaiun s cndifion (70'F.

of water - 1054 [tufib I atm) - 0.075 lb/ft 3

= number of occupants Subscipts

qE = heat input from electrical L latent

equipment. Stulti

q p = h e a t in p u t fro m e t c h v an T e c o i g l a a c l t o s a e zoccupanL Btu/hr Tecoigla citos•¢:

follows:a = otata heat input from van

occupa•nts, Btutihr 1. Transndsion and Solar Sensible Ifeat

Gains q throug %vlls and q through

q - heat input through floor, roofBtulhr qr. - Area (ft'/ x U-factor x Efluir-

q = heat input through roof, lent At

Btu/hr

a. Wall (1) facing North (Refer to Fig.q, = ventilation air heat pin. C-1)

Btu/hrS= 82 (0.35) 12 = 340 Btu/hr

q. = ]hat input through wall,Btu//r (Note: Ste Table C-2. or similar

tables in Ref 4. for equivalent tern-= ventilation air flow rate, pe turedifference.)

cfmb. WalN"'facing Eas-

= dry bulb temperature ofoutside air en~t.ng air con- q, = 46.5 (0.35) 14 230 Btufhr

ditioner. 'Fc. Wall (3) facing South

t=(if) dry bulb temperature of airinside conditioned ce, 82 (0.35 4! = 1180

At = I,/DB) - t/DB). OF ' Wall (4) fadng West

qm = 46.5 (0.35) 22 = 360 Btu/hr* Equtdei: At A r correc:ed to tae solar

radi3tion into account. OF e. Roof

w = pounds of water VaSor per. qf, 80(0.35) 64 = 1790 Btuihrpound of dry air in okdeair (Note- See Table 3-38 of Ref. 3. or

similar tables in Ref. 4. for equiva-i pounds of water vapor per lent temperature difference.)

pound of &-y ar inside con-dtioned space Z 4sw +oq_ = 340 + 30. + 1180 + 360

"" specific wegit ot air at + 1790 - -W900 1tahti

(C-4


TASRLE C,2

TOTAL EOWIVALENT TEMFERATUME OIFFERENTIALS FORWALLS FOR APRIL 20 AND AUGU6T 34*

Aut L1fs ,1,fLL - I U

0 L!.LL .. LIDLDLj

33t 0 ) * 3d ft A4 :: 40 4 4 1 J 4 4 4 aKto so...A ..3... ts teje 24 as sv 1 : o .: 11. "s : el 4 e

:w 1 - 2t * 314 "5 1s4o I0 I44 4 Is di Si.U a 24 at t 07 so488 3) 5 4 2 04 A a S

of.aa .2 4 2 1 0 1 AD wa is tis to S o 124 tO to so 0 * 2 49 tas.41

toa 0 -a a it Ito1 101if a #A S~t- 4 4L14 :0 :2 : 4 1 : fite *1 2 . 1635 O to to 14~*i wSAd * e a, SO ~ 14at 1. 09 4 * zv so at1) 1 :: tue tott 1 It t'0 a ai

a a 01 of o~e 34 Is 1854 9to so ta 644 toj 4 4a -o a - 7.1r-o 3 I t 44 35 "7 -oSogf"0*4 : we sto %4 as %a 384 ta it0 0 S*M

1.w44 0 is 8 0 is 0 12 I t It4 Id 4 4 is to 6 o 8 a9.e

44 a 2l 1 aT to I'slt toT 41 $Iw Iet ej~~T f 1%

* ' 0 I's is 11 149 t1

ab4 so vs woul *.4. 114,v es ca c.01101 4140"

A 40 494 414 is t O!91 tD a 14 1 04a Io a to a to I* 01 tso t tot :915 t: 18K

014 1 1 .fag to i ts I'S 41SO~4 4 1

a 0 to toIS0 t I0 a IS~ .-Aeat

a : 10 t o~ 14 10 48 14 4o1 .. t216 I C 4 0 4te a9 6 $a 011 c So So9 tf of1 ie 2 t 2 4 w

13 4 62 40 :0 ett1.0 s 7 4 t 41.- 41* iS a 62 9 $a Iwo i# 4 it * *! Aot it I * t4;* z*t wi

$1W to 0 4 0141 to i 0 Is It !t So .0 fa i* 144 .61 Stl t IS _!t 0 0 42 6 ta t e -610 a ea

0 11.0"¶ of 43 4 4ogde f 0 0 4 0 00t&

W- 7 I is 4j1 :1l 3t :% t lt 14 s

Ke a 0 v4114I *410 it 8t ii 4119 30a4 2t 4 3 to 1*8 408 to IS 11 1111 tzft IS *A

;w iu 4 e .6 ts 0* 4 wga ? 1to At 17-j 3 3 S3 [if

qt 0 4 a 1 w031 46 *2 if a6 6o 94 aat t8-W a~C 4 0 6 4a Ito 10 a4 8 0 0 0

33-eeh)~ U jis a , S;4 40 08 -

ofC40~#0 14

44 ?4 p4 P 04 0 *4Ol 1 0 .' j it to 4K 8 jt 10 of1 61 05041*0 I'l "0 8 4 ) . 1 1 t5J4. J 0 :3 ** ts ti Is. toiso is 4*S

a1w 6 0 7 0 7 tO 10 0 a 11 se;?t I as 14 t "

44 1 to vv00 0444

94109 C-2 Is fm 4Ci day wtw4lt It Play be %.Aid for 4g4 witl~ftG few *b~t,4e 20 Ora Octimbor 23.

C-5


2Tnmfmzizssi Jmew cidn v,"* P76W that the motible heat kosm from fte &r

is appmumtely 270 Stuilpr/Peon.

Arco (fil) xU-facw~to xj At -Nx qe.

80 (0.35) (125 - 0) = 1260 -2 x 200 -400 Iizulhr

b. Lagent ftwt

W sau4gfe kpspbnt

shelter) Thr, latent hat loss by a seated mnit(&~zl h&asaarni fise200ampeneat

3.IfWz Ggat Of Venikdonk Afi-Scnlibk petSmf.aond W~ernt q

a. venhikadon mit:

Q =No. of persmi x vendblwu rate(cfmi per Pmp 3 EwowrX Healm Umahiiugt

Q2x 1SqEWantag ratla x 3 4 fBrluhr)

Q30 cfm 14wtt

b. Sensibe hewr gun; 3160 x3.4 = 10.740 Btufiu

q. Cp -Y (6 0 Wl(Du) 6. Swmnwy of Hw: Cebu Z%:

- t 1DE~lSenibkLe tent.Bhftlhr Ins/hr

-0.24 x 0.075 x 60 x 30 (125--

-~ - ~a. Tnmumios, and-80 a 460stut s~w wdsad wocf) 3900

c. L*:ent hewt Von.:umkl ft ) 16

qL, -L -YO(60 0) hi. -W/ d. Occutv s 400 400054x007 S~0x30 e. Eqtipmmst 10,740

-I S4 WSx 6 x 0 Ttal17,760 440(0.011Is-0.01Is) wfth vulusesof w detesruine from F*g A-1 T&e following psmqqu, per. C-3, $Ives an

(Mutlm of the poced~we for selecting an air

Note: No outsde air intihtratiou pin and coong lW&e us *ven in per. C-4, Appen-

4. Heet Goa~n from Ocrujuo-Serableq; wd fe ierqj.. C-3 EXALE OF AIR CORl1W1

IELECTMOa. Sntrift Heat:

In tbib apwapb. we tdwicet doutonFollowing Ref. 10. we win gwimn cooding Woad cowmpuatom ivnn the Pw


AMCP 70e-120

C- .1d show howv to select an air condi- To proceed with the example, we will use,!io~ ~equipment capacity and performance tables

V/ have:(CA- through C-7) taken firom Ref. 10. SinceI ) mbiet ai tenperttjt-s:the sensible heat ratio is iiearly 1.0, wj: canI ) mbint ar tmpertii~s:use: Table G-3 to make a tentative choice of

air conditioner. 1ble C-4 can be used when,,/I); )= 125)F the sensible heat ratio is substantially lower

ta(Whll , gof than 1.0, but Table C-3 always yields aIre:d conservative choice. From Table C-3, we sý_eConditioned air space ttmiperature thtte 0-z unit with a nomidnal capacity

t (D10 0('1-'of' 8,000 Btu/hr provides a cooling capacityyi~h O of 18,300 Btu/hT when the temperature of

!PV(IV) 67.5 0F the air entering the condenser is 125"F DB

(3) Outside ventilation air flow rate: and the temperature of the conditioned airreturning to the unit is 80OF DB, with SHR =

Q 30 A'fm 1.0. For accurate selection, however, it isnecessary to compute the actual temperature

(4) Rate of sensible heat gain. of the conditioned air entering the unit. FromTable C7-7, we find that the free air delivery

(s=17,760 B1tu/hr rate is 710 cfm. Since the rate of outsideventilation is 30 cfm, this leaves 680 cfrn as

(51 Rate of latent heat gain: the rate at which conditioned air enters the. q 40 Bu/hrunit. Computing the calormctric average tern-

44 =~ tl'i perature, (30 x 125 + 680 x 80) 710, we findFro~a the given data we find that that the dry-bulb temperature of' the mixturethe total cooling load is will be 820 F. Returning to Table C-3 andq = (1 +q 18,200 13tu/hr interpolating for an entering cooled air tern-

perature of 82*1F DB, we find the actual(6) Sensible heat ratio: capacity to be 18,820 Btu/hr, which is more

than adequate for the application.SIMIz qslq= 0.98. If supply or return air ducts are vsed, the

TABLE C-3COMPACT-UNIT COOLING CAPACITIES (BTU/HR) AT 1.0

________SENSIBLE HEAT RATIO AND FREE DELIVERYNOWýJNAI. COOLING ___0_ "a_____SUPL

"_Ivia_031 its 125 02 ItS 122 00 11 6 lie inli It in5

COOLING AinR- so -7w- tosb 90900 "W-a -2 140 ii000 IVWIW 41O 37400 34200 6W WXDR~Y BULB3TEMPER~ATURE CS 930 7700D 7000 11500 10400 9300 7"W0 21000 M300 431100 4030 3"W0 690M "37W 56500

WNIOI4 &0M00 60 7500 12100 11100 10000 34000 23400 -20600 4590 43700 39000 72900 47900 43900UNIT. F 93 -9 400 60 700 I 1100I W lo 2si00 2w 218 40001 42W0 7630 Y - 0400

NOMINAL. COOLING 400 "a CYCLEK POW V11 SUPPL.Y

l~?, ie IS 126 as ISO in lie in6 a it* 1in a 1i6 in

CCOLING AIR so 7201) 1100010000 0600 220 20o0 530 6440 41100 27V04000sa0TEPERATURS 40600 7600 am 10700 273 2100 1940 430 4W 5 7W WH -&

ETERV4F

lCourm2s of Trane Comnpany)

C-7


TABLE CACOMPACT-UNIT COOLING CAPACITIES AND SHR AT NOMINAL

MILITARY CONDITIONED AIR DESIGN CONDITIONS(5>0% Rellatirew Humidity) Free DelIvwy

lie _2 I m6 li-nia t nle i

* 76Ck16 9 4?I Il 71 91 tO III 75IS I 1 ItO

I.~ 6 ' 58 .61 6 6 .62 65 60 .621 .41 .9i 64

AL~nL~~c400144 P0110faf $UFrLv

I:.O~~t~o viax It I, tsto 17S Ile 1 in~ Its t"I

Nis. 1! 9 ~ 7 0 70 74 19 1317 S 70 .73 7, t4 7

65 70 '73 64 f.4 .72 67 1~ 0 74 '1) 67 70 7

1000 9Z~)660 400 jRiJ 11700 2900 2610 17000 0IW 94t, 70 92A00 64000760; .602 6-3 66 58 .64 60 .63 .6 9 621 64 62 6

(Cotn,':sy of Trano Company)

TABLE C-5 TABLE C-6LQCOLIAJ ORCIO ATR COOLING AND SHR CORRECTION FACTORS

ju 1'abI, C 3 Cooling Capoctiute for CFM other then SlzndardI "woi "Itat ilorip.) (APPIV to T.03. C 4 Cooling Cepatcit,. for CFM othw th~n StandardI

10 7'A~f0 .Fo.d of 20 yi1' 40 COMPARFD 10 RA! (1 lrNoted 0 20 130 40P QUANT11Y

COX.JLING CAPACII,AP(A! ULTIrPiIR 1J 00) 97 94 9

Stilt MU.hTlftlil 1.01) 9979 11

(Cutzv ofTraý, ompny)(Co jrtsy of Trmne Company)

TABLE C-7CONDITIONED AIR FAN PEAFORMANCZ-CFM

~~R1111 I MXIUNL STATIC IAISSURI*

INTRL/au a.MSO WATIN)

600/60 240 220 lo ISO IDS% RIEUCTION a 20 38 566000V/400 704 260 225 210 175 135

to3 1 33 4a

oo00io 315O ~j* 25 250 i26-% R(OIDTO 5 13 21 301600(960 330 315 295 270 240%RIE UCTION - 5 11 16s 7

16f0Z0Z400 ON 6S 625 SOU 530 .370 335%__ R ____ 5 11 1IV 2 49

4000/ 710 600 645 6C'1 545 420ZRRCUCTION - 4 9 16 23 41

% M0UCTION -__ 621 12 Is 2_

400 375 1308 1230 1160 30110 900Zvcfrl2CTI2 1- 1 I 6 21 35

60006/60 203 330 3850 1775 165 3500is%REOUCTION - 4 6 12 36 25

60Q400 Ifoo* (4 6 P1775 13590_%0 MMSIO 24

-WET COOMING C OtL 11131tAANC INCLUDED IN UNIT,0

(Court.,y of Trene Comptany)

NOTE - The above tablet were taken fromn R f, 10. Modeolnumbers and other data for oompact units werqiven in Tabe 3-1.


AMCP 706-120

cx tcrzial static pressure must be estimated and them. The first step is to define the internal.:-rrections appli,-d to the air flow rate and and external design conditions accurately.•oling capacity. In the given example, for

iid.Aance, if the pressure drop through the C-4.1 INTERIOR DESIGN AIR CONDI-c"ut-rnal air distribution system is 0.5 in. of T'IONwatter, Table C-7 shows that the rzte of air Different combinations of temperature,d: ivery is reduced by 9%. Then, Table C-5 humidity, and air movement will produce the

ws that this has the effect of reducing the same relative feeling of warmth or cold incm'ing capacity by nearly 3%. The corrected humans. Studies using prolonged exposures ofc;oling capacity would be about 18,250 test subjects to various psychrometric condi-Wuliir (18,820 x 0.97), which is still ade- tions showed median responses as indicated inquate. Fig. C-2. This chart also shows the line of

maximum tolerable conditions, as determinedIf the :scisible heat ratio is substantially less by Yagloul. This chart enables one to pick anthan 1.0, Table C-4 should be used to select air condition, or condition line, which willari environmentai control unit of adequate yield a certain quality environment. Thecapacity. In this case, cooling capacity and "comfortable" line on the ASHRAE Comfortsensible heat ratio correction factors for lower Chart (Fig. 2) is desirabl e ASrAeM292 Vanthan rated air flow rates are obtained from interior in all its uses. Since electronic equip-Talble C-6. ment .nay abound in the enclosure, tile

Finally, it is well to caution -,against over- humidity should not exceed 40%. This designdesignofallyitem by selocation ofgair condi- point is indicated in Fig. C-2: 77 0F dry bulb,design of a system by selection of air 61*F wet bulb, 40% RH, enthalpy 27.4 Btu

tioners which are !.:.• •,,r thin necessary. Over- per lb of dry air..zapacity may resuli. in poor temperaturecontrol and inadequate dehumidification as a C-4.2 EXTERIOR DESIGN AIR CONDI-consequence of on-time being short compared TIONto off-time. Furthermore, the larger units aremore expensive, weigh more, and require The exterior air condition which should bemore space and electrical power. This point is used as a design standard will also be aillustrated by the following example 2 : function of humidity as well as temperature.

Net every combination of temperature andNominal Unit Size, Btu/hr humidity is met throughout the world. Mac-

Donald 6 has studied the probabilities of40,000 60,000 % Inease occurrence of various conditions throughout

the world. His data are plotted in Fig. C-3. WeWeiUiit, lb 445 600 30 have chosen to design to the 99.9% probabil-Power Required, kW 9.8 15.5 63 ity line. Just which point on thi- line will posSize, ft3 17.4 26 49.5itli.Jutwihpitoti.lneilps.the maximum load on the air conditioner isCost, Based on

$O.10/(Btu/hr) $4000 $6000 50 not immediately apparent; this will depend onthe relative importance of radiant and con-

C-4 CALCULATION OF HEATING AND ductive heat transfer and the interchange ofCOOLING REQUIREMENTS FOR latent heat in the system. The only reliableM292 VAN* way to determine the maximum load is to

take a range of conditions and compute the"Tb', heating and cooling requirements for maximum load. Table C-8 lists some choices

t.e M292 Van can be determined by con- along the 99.9% probability cuive.sideration of the various heat sources andsinks, and the modes of heat transfer between C-4.3 HEAT LOAD CALCULATION

Fig. C-4 gives a schematic representation of*Th.s appendix is an edited version of Section VI of Ref. 7. the various heat sources and sinks involved in

C-9


NMC? 706-129

f AIR Mjv.-VMCNr OR TUnDULENCEBER LEP

15 TO3 25V E INCNIIN

~A

--

~Y V~v00

OR BL EMEAUV,~

Fiure C_,oie SHA(CmotCh~r oyihtdb SRReprnte by ermssin frm AHRA Gu~e ad Dta Bok 907

(Tecofrtdstiuto cressi~wthtth ixmi'vpecntg o eoi soldb

t-o


240

200

905

Cond It ion

Line of CwcfortsbieISConiditiont-

140

Nil

110

45 7 7~W SB it s oo~ J0 "s~*oi25 30 3~ I~ go

~V ~LBV~Vso

Fi~awc-a ~cftm~ufk TO

toI


TAM.!Cd + 220 Mutijb weAtc heat) Met.1 CCN MW A U9%4)FOM"ffvqW towa hest input throuh roof, Btu/

A 0 111 63 t q. Vtowa beat input thmuolg wafts.

41 10 11? 12 36A t T

C 20 114 is 412 - heat removed by air cotndi~onr~,o 40 107 86 4" Btuftr

so 00 5A = eth~alpy of air at d-,!j point miF 100van interior, 1hululb

ftRd from F1s. A-i. enthalpy of air outside van, Btu/lbtRa ftm Fig, C-3.

themmlsiLIn hisfi~m, A air flow through &i lock. lb/hr

q -m4 hetiptfo 3cia qi-Q ak leakage, lb/hr

meatRtu/r (4+( mankcup air flow. lb/hr

-bWa input from each van occupant tj =interior temptnture, *F

Ma53 Bftu latent heat.t extertior ah, temperature, OF

q or

IIqm . Iý-4

Fipre C4. MWa $ouaum -IWIs &Wd Swfc IHeo Ti'wuf#in U292 Von

C-12


N = number of occupants .iflemtil h not a'ayz the ' I SF ork whichthe abe in the ASHRAE Guide ar bmed.

Ow - conditioned aWdr flow into van, Ihr Te ptocedue ford rkitnsg thew correctionstu desen fod in the Guide.)

I.ols that s of and Loseu at Van Surfaces. With these o editkms w iatnd, the Eqera-Sunrwer Condtiwon lent Temperetne Diffelles can be rea-

from the ASHRAE tableks and appropriateUc'h ASHRAE method for computinlg concreatkos applied. Cafftticns will be dif-

beat Pin (or tov=•) thwus waWh and roofs ferrot for each of the chosen extzrior designinvolves the use of an "Equivalent Tempu•a- conditions. Fwthemme, the FEquivaknt Tern-tuse Diffamntial" which suns anl the effects perature Differeces¢ will depend on the rela-of radiation and conduction (see Ref. 4.). tive position of the sun and the van surfaces

We hav- assumed that the sun will be high inThen the sky to j-fve maximum roof ttrmfer; we

orient the van with its dde wall facing south.X d4, z2d t4A, (C-) The remaining wal wi be shade Tabi C-9

lists the Equivalent Temperature Mernceswheiv for the chosen operating points for A four

walls and the roof.• = area of the ith element of the van

surface, ft2 The next step is to determine the natureand area of the exposed surfaces. The con-

total heat tmnsmiussion through figuration of the expanded v-ja is shown inthe Ath element resulting from Fig. C-5. Fourteen separate surfaces make upboth radiation and conduction, its exterior.0 However, we cn p•oup s•,me ofBtuI(hr-ft) these and reduce calculation. Thres areas.

together with the proper EqWi-alent Tempem-" equivalent temperatur diffner ture Differences, are fifted in Table C-10. Theenfial" for the tth thment, "F othr entrift in this table are expl.ined in the

paragraphs which follow.= heat trasfer coefficient for the

Ith eement, u(hIfrt 2 .:-F) The van walls are made of a tlhee4ayercomposite, consisting of a metal exterior skin

Taking the roof fitt, we awarme the follow- s, glass fiber insulation I. and tempereding fiberboard interior panels p. The overall heat

Stranfer coefficient U for the composite walla. The roof is equivalent to the "ligh is:

contstrution" line of the ASHRAE table ofequbralent temperature ditrentials. U ((-2)

tK We ue the *wst ac e for the roof as . + _ ÷determinlng 2 P~M on a sumirtr day. k

c. We corret the differential upsar4 w tf"w W WV sR.7.F i "fla continuous 9S*F day, rather thin an asua wi" be.7 F tsummer day vaying from 75V to 95OF as .S i th t oh W.rm,-Mstate in fte table; the camrction is 10 dtg at *W- beftm OM POW ow "4for hiL In additiom, we add or subtract a air_ fto t e Otr6temperature difference which correts for the Wta a" d, ami OM k f iW1 to 0 1 OWfact that our interior-extedor temperat 0ure

C-13


TAKEI C4ICORRECTED £OfWVALENT TEMPRATURE DIFFEREN~CES

aulk~w ROO H NWuII WON f wa W8114

A 97 46 65 47 5a 9) 46 65 47 56c 94 42 6244 50 87 36 56 37 45

al 29 49 31 39F so17 3~7 19 27

FiEKt"M .5 Exgadw) (Expq~owf (M292d Vshdw

C14P'

II


o Lot

fa

4C M

to -Cvt

to to

RR-

oo

ru 4K-Z


Whmr laytr lh~ckrxm es 9 = 60 Q~I-6. BMu'h Iv3

5tf= 3116wn. WhereR, I in_. the wedfic wdajt of theoutiik~ar

VP toWa buat introduaced by t*it 4rAnd layer heat tmisler coefficients k are: Stu/hr

ks 1.0 Btu/(ft2-hl&P~ftr) h = alpy ofuiro*uW&van. B~wb

k, = 0.27 Btu/(It'-hr-!PT/M*) The beat removed by air Jeakap and sir lockflow will be

k 08BtUI(ft2 _thr-0FIý.n)$'q, = 60 hj.Btuittr (C-4)

Substituting.where

U1176 + 1/8 3~ 4~totis beat IWby airflow 6utward.

2 (0.27 018stf

-0.26 Stu/0ur-t2-PF)* tebhaJy of &i flowin ou~tward,

2. Otewr Htvt Loim .d GWeba BvwRtr

a. hnermeXL We asime that M per- iumed to~ be 2700 W, ov 9200 Stulhr.Man we1 m eupd M I* sL~at I WWcLuk".ah La* i ttKef. 8 esh 750 B3W/br totd but aOUV Per ka sO abo- s f hepvodnun in "h situdion'9. MW bo, t~c

b. F-Werix S4d Leafn Air £ii%*y Ar.~oa e bdWe mm 00t t5 efm of Mknq * vMbe UOM (bAt

airwindepnd n d co"= l~qM&+ (hest frix oC-8. Air demids clIVR6t u COiP80ft)

conwaman W a th to ofext+ ;bhest frogaM jle%ýcetmctnm~ of T*Wk C-10; lkwm wv triC~l eqUip.

Obtak" fr(M ftDexsuity MwCast, F. R& 6. With theM data 45 LMd the + (bUt ft*M Mn

heal Ob*UfM9 am t esset * ;be c1aktod for Mah CMeUbA)14 giuig the (hen in leuag

exprewim

*WM ** *ad Wb% 41~ ft SM IN .-L -~ S ts o ob& boiomw qrzW Alw md to A& afb It

-b BW is*swM a too pis P A-?. Apo$& A. ftswod Uvedib &fsil ,-f l~M s"if a a

C-ý6


I)~ $4

I

I * !|-i-

I I ... .

I '.


AMCP 706-120 -

"i11w-c five terms and their sums are listed in qc = total conductive loss, Btu/hrI .1c ('-10. lhe maximum load appears at thecUlllit~on of saturation, E and corresponds to U = heat transfer coefficient for the0.6,0 tons of refrigeration The bulk of this walls, 0.26 Btu/(hr-ft'- 0 F)lo.,I :,• in the incoming air; unless the ventiia-ti',ri rate can be reduced drastically, this AT = total area of the expanded van '

cooling load cannot be reduced. This quantity 1040 ft2

ot Aitr i's almost certain to be required forsevw.,. reasons. Smoking is one of these; At = wall temperature differentiald•i,,ipation of odors and flammable vapors inm•dicad air stations, and rest and relief uses is = [60-(-65)) ] 125 0F..inoth.r, metaboliz (oxyg-n-carbon dioxide)rcquirenient is another; the need for reason- Substituting these values, we have q.ablc air conditioner discharge temperatures is 33,800 Iilu/hr.3till another. (Ventilation requirements arediscussed further in par. 1-4 of this hand- -- For the heat supplied by occupants, webook.) cannot assume that the van will be fully

loaded; ihe worst case Is a single occupant,supplying 750 Btu/hr. The wont car. for

3. tleat Gains and Losses: Winter Condi- electrical power is perhaps 200 W or, 683tton Btu/hr. The heat to be supplied to entering air

must be based on a reasonable flow rate.The minimum design temperature for Since there Is no provision for lowering the

the van interior i3 600 F. Again assuming 40% flow to accommodate a single occupant, thisrelative humidity, we have a dsign interior flow would be 375 cfm, raised front -650 toenthalpy of 19.2 Btu/lb of dry air. The 60*F at 40% relative humidity. Taking theexterior condition is -65"F; humidity is of no enthalpy difference, 119.2 - (-15.6)) or 34.8,jgnificance here. The heating load iJ corn- Btu/lb, and a d,:nsity of 0.1 lb/ft3 , we haveputed in a imanner similar to that for the heat gain q, of entering aircooling load described in sub pars. I and 2 ofpar. C-4.3, = 375 x 60 x 0.1 x 34.8 Btu/hr

=78,200 Btu/hr(Heating Load) (heat loss through

surfaces) Summing terms, we get for the heat to be- (heat from occu- supplied

pants)- (heat from electrical 33,800 - 750 - 683 + 78,200 = 110,567

equipment) Btu/hr+ (heat gain of entering

air)

C-6 ALIGNMENT CHART FOR %ALCU-LATING COOLING LOADS

The first of these terms is much simpler thanin the summer case; the worst condition Is at Fig. C-7 enables one to make a quiAknight, when no solar heat is available and estimate of the cooling load of a mobilelosses are purely conductive: structure. Larger, more useble coplex of the

chart and a booklet explaining the methodsq• tu.t, Btu/hr (C-5) used in developing the nomograph are avail-

able from the Ellis and Watts Company,where Cincinnati, Ohio.

C-18


AMCP 706-120

~fit

it. 0-'

rlrr = ,,,I...F-77 JJITTIF '" I1 1-

II wo 1~

C-1


REFERENCES

,. r,:cy "Effects of Altitude on MIL.-STD-2)0A as Compared with

t Performance", Air Condition- World-Wide Weather Data, Mechanicalf: Ing and V,.ntilatiwg 65, 41-48 Dept., USAERDL (now USAMERDI'),

I) ;Fort Belvoir, Va., May 1964.

"i lle, :iineettug Bulletin, Military Air 7. R.D. Rivers, K.L. Westln. and R.J.'• ,. 'r Selection and Application, Boylan, Collective Protection for Corn-

10, Pir. 67-86, The Tiane Co., mand Post Vehicles, M292 Desttgn Studyr', w, Wisconsin, 25 June 1968. Report, Amer. Air Filter, Co., Inc.,

Louisville, Kentucky, 4 May 1965Co., "rane Air Conditioning (AD-462 507).

''1, .9th p)rinting, The Trane Com-"y,1 •.r osse, Wisconsin, July 1967. 8. ASItRAE Guide and Data Book, Chapter

26: "Air Conditioning and CoolingI/%, Ilandboo/k of Fundamentals, Load", Amer. Soc. of Heating, Refrigera-Th. of' Heating, Refrigerating ,and ting and Air-Conditioning Engineen,'jr-t 'Irliioiiing Engineers, !nc., Ncw Inc., New York, N.Y., 1963.

"r ý4 , 1967.9. R.E. Franseen, Cooling and iteating Load

r, , Tolerance Limits of Ppople Calculations for Environmental Control-, : 'k,,at and Hlumidity in Under- Equipment Applications, U.S. Army

;::,,ld: '4zelte'rs, Proceedings of the Meet- Engineer Research and Development,,n -- Iinvironmental Engineering in Pro- Laboratories (now USAMERDC), Fort

-ct,.,, Sh•w.ters, pp. 31-40, February 8, 9, Belvoir, Virginia, 10 September 1965.

10. Trane Catalog DS-239, Lightweight Mill-0, i•,i•n f. M4acDonald, A Review of High tary Air Conditioners, The Trane Co.,

"/'tlictesfre Extremes in AR 705-15, LaCrosse, Wisconsin, May 1965.

(C-20


AMCP 706-120

APPENDIX D

AIR CONDITIONER TOPICS

'0-1 IECHNICAL. CHARACTERISTICS Appropriate components will be treated forFOR AIR CONDITIONING, VAN TYPE tile rumination of interference with radio'Copied from Ref. 1, pp. 6W-70, with communications in accordance with appli-minor changes in Item I .%) cable Signal Corps specificationi.

"1. 'lhl- air conditioners shall bc designed th. Be air transportable as a part of theto provide the environment within the van, item of equipment in which it is to be used,hut, shelter, or enclosure that is necessary to and in the same phase of airborne operations.insure proper operation of the installed elee-tronic or other sensitive equipment, and shall i. Be capable of operation, as specitied,

at one or more of the following voltages anda. Range in capacity from 0,000 to frcquencies: 120, 208, 416 VAC and 60 or

1 80,0(0() Btu/hr. 400 cycle,

b. Maintain temperature, humidity, and j. Be capable, where required, of being/r,-h ai circulation necessary for proper driven by either a gasoline engine or anfunctioning of the primary equipment in- electric motor.stalhkd in the enclosure.

k. Have mecharlrI and electrical partsc. lie equipped with dust filtering de- adequately protected to prevent injury to

vices, personnel.

d. When required, be compatible with I. Be as light in weight and small in bulkchemical, biological, and radiological (CBR) as is compatible with other requirements.filtering devices.

m. Be constructed of readily availablec. Be capable of being mounted on or in noncritical materials as far as practicable.

the associated van by organizational mainte-nance personnel without requiring extensive n. Be capabe of being manufactured inmodifications of the van or interfering with quantity by modem fabrication metho'J.the .ffhcient-Operation of the Primary equip-ment. o. Be designed with maximum simplic-

ity commensurate with their Intended per-f. Be sufficiently rugged to withstand formance. Ease of operation and maintenance

prolonged cross-country hauling in a mounted to be considered in each feature of design.position and be capable of operation con-tinuously for 6 months without a major p. Where applicable, the design of theoverhaul, unit shall be such that its operation will not

interfere with local radar scanning devices.g. Operate at a noise level such that It

will not interfere with the efficient operation q. Be treated to resist fungus and mois-of the equipment in the vats or shelter. ture, as specified.

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MAPCP 700-120

Where required, be capable of interior "Liquid refrigerant flows from tie receiverwl cxterior mounting and be designed for a through the drier and sightglass to the evap-

,v1,XIzu inumr ber o'a;,plieations. orator solenoid valve. The drier removrs

foreign particles, sludge, and moisture fromthe refr4gerant. The sightglass pro'ides an

.I1v,: the inherent capability of ac- indication of the quantity of refrigerant in the,-.ptable performance tinder Basic Operation system and the,... prefer, el of moisture in

f , nd'lliorvr ; rad Extreme Hot Weather Operat- the refrigerant.', (Cnditions as estuiblished in paragraphs 7a t.

.uv! 7. of AR 705-15, Ch~lnge I W) , exceptiif operation will not be roquired at amble'it "When electrical power is applied, the

terntratures of +600F1 and lower, and shall evaporator solenoid valve opens, allowing

•w c;atr)ahc Of safe v,,arage and transportation liquid refrigerant to flow through the motor-

,.Mder the conditionm, as established in par. 7d operated valve to the evaporator expansion

ol AP 705-)5. Change I ). Where electric valves. The motor-operated valve responds to•,•' ,;e specified and are in integral inputs from an electronic temperature senainghatc ent, -x scapable of providing the rated circuit, opening and closing the refrigerant

cotiporient, be the unit at a minimnug r lines, land thuJ] modulating refrigerant flowhempitin re oo-t0ut *. in sries with the evaporator expansion valves

to maintain evaporator discharge temperature

t. Where necessary, be treated for the at 730 t 30 F.

tijinijjtioii of interference with radio com- "Temperature~cnsitive expansion valveilitirini~t~ons in accordance with applicable sensor bulbs are strapped to the outlet lines ofSipial Corps specifications." the evaporator coil. As the temperature at the

D.2 REFRIGERANT CIRCUIT WITH HOT- sensor bulbs increases, the expansion valves

GAS BYPASS open, allowing refrigerant to enter the evwp-orator coil.

Ilie refrigerant circuit described, quotedI he refritger5ntfcircuit desypribed, cirouits"Pressure inside the evaporator ,;oil is keptfromi Chapter 5 of Ref. 3, is typical of circuits rltvl o ytescino h fieausing a hot gas bypass for temperature con- relatively low by the suction of the ifngcrsnt•ro). Refer to Fig. 1-I. compressor. As liquid refrigerant enters the

evaporator from tile expansion valves, it is

"Cool, low-pressure refrigerant gas enters vaporized by the low internal evaporator

th, refrigerant compressor through the suc- pressure. The heat necessary for vapornwation

tion iervice valve. The cpmpressor increases is extracted from air drawn through the

the pressure of the refrigerant gas which I,; evaporator coil by the evaporator fan.dis-harged into the condenser coil throughthe discharge service valve. The temperature "The cooled air leaving the evaporator coilofthe refriargern gasev incrvalved b themheatu is supplied to the area or equipment requiringof the refrigerant gas is increas d by the heatai o d t n n& A a r ii c ol d b thol omrioair conditioning. A; air is cooled by the

fcompression. evaporator coil, moisture in the air is con-

"AM the warm refrigerant gas flows through densed and drained off through Jrain howes.

the condenger coil, it is rapidly cooled by air "Cl refrigerant gas leaving th. evaporatordrawn through the coil by the condenser fans.AM the refrigerant gas is cooled, it condenses coil wturns to the suction ide of the cor-and ii stored in the refrigerant receiver. prissor and the cycle is repeated.

"During periods of operation with rela-*Tbe mIdnum tempwmtae was iven w .65P In Rd. I. tively small heat loads on the air conditioner,tAR 7o5-15 has beow emdissd by AR 70-38 Rech, Insufficient heat for refrigerant vaporization isDertlopwmt. Tat, and Nnhot M0MtfeOl/V eWm'arimmt Condi,,on, s May 1%9. drawn from the evaporator airflow. Under

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this conditon, the ueffigunt suction pfcssuft "O1W rum*= of rkW cool reflIPMnn enter- 4

starts to drop below tokcianc4. WSthe sRction sIc of the COMPTCOM is to 4provide Cooim for the 'Cofrcsor motor.During hot go bypm~ apemtio. the tempemawtM of the sUctOM fS besses, moslting M 4

"~Wtmi suction Presm"dee Case$, pitSwe Uncreased cm mso ternui temperaturmssaminS tuoing connected to two hot ps The orbulb of due quenchidg expinsimbsypass ValVes opens tk-t brpF valves Warm, I&ve zelaS the sution temnperature increaseshigh prceure refhrmnt Ps from the comn- to the qunchIdnS expansion valve. Liquidpressor dmscwr flows dk..tiy into the suc- reffiserant is evaporated into the RMUcto line,tiof 111,. tteporg suaction preaure above reducing suction tenpemture to within tok-r-low'er limits. an= during bypass operation."

REFEREMME

I. R.B. Sherfy, Nomndel 36. 000 Rtulkr, Cof t- Resewrh &iteloPment. Test. and Eiake-&Ienfkdon Sguzrfrd Wei.k,: S4hwgkeSeca"~v lion of Murefiel for Exrenue (2imak2?08-yale. 3-Phase. 60-cycle (Mo~dl Condtions. 5 May 1969.)CE36HEC6-2081 Akr.Coetlowng (Mu,Repor 1854, U.S. Army Ea~me Re-ueud. and Development Laboratories(now USAMERDC) Fort Belvarnr Va., 3. TM 5-4120-295-15. Air Co~dw erwn.. R007

Maw 1966 (AD-48 623L). Momqlftb RW.Cood 60.0010 Itu fr."2'81416 YWUt 50160 cycle. 3J4ese. Car-

2. AR 705-15, Ogwemdcv of MkiwWi Ukor Hier Air Coxdltioning Co. ModelExreme Cbewtkmu of E,*'owmmc, 4 76E34104. ffeakmiatv. Dept. of theOctober 1962, inchxl6adin 1~p , 14 Asmy. Washingtofl D.C.. 7 NoiitmberOctober 1963, (Supeseded by AR 76,38, 1966.

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I

APPEWOX E

COLLECTIVE PROTECTION SYSTEM (CPS)FOR COMAND POST VEHICLE*

A drawing of the recammeedcd ClPS fo( ported by external fram 127) (shown only inthe M292 ExparndabLe Van is shown in Fig. part). Door (30) is j f1ap door tc Alow rapidE- i. entry witi litter cams. Entry (2M.) i! necessary

to allow, flap door (30) to hang vertically andT system provides mobile protection for seal propeAy.

equiprment inside the van, plus up to fourpersons also ridings inside. To accomplish Luis, Cables (16) attached to the van and to theliner (9 )tjS instAlled permanently in the van door frare around door (24) support air lockbody, and a gS particulate rdter unit is (0S) when the system ts not pressurized.instaled between the ier and the shell of the Straps (17) are provided to suspend a littervan at (3). Connection to the outside is made inside the air lock for the decontaminationthrou& pipe (4); disehauue from the rdter petiod, LAmps (18) and (28) are provided tounit is directly to the interior of the van liner. illunmnate the air lock and ante-room respec-Fold bags (10) sr pwrovid at each corma to tively. Telephone jacks at the control stationallow dte Une to folw inward with the van imid the van (6) ins the air lock (22). ana3W pmels. both imide and outside the ante-rom (31)

allow communication between the chamrbers-

Limr (9) is attached to air lock (15) byzippes (14). A staircase or ramp (19) is Contra of air flow is provided by control

b"Wied i this a 1oCL In moo cases, panel (5) connecting to vahves (12) and i23ýex•on (21) wil b • onto ok through cables (8). Power Le also tcd through( wuso G O w)a L T ill be At e reson to ai slick cable (7) to externally located filter umt ( I •(IS) at (20). This extension allows a S* th* These units can provid the flow of approxi-doo(24)to be used at thenoutreend13 fthe ey 400 dium qui•A for use of the tanair lockas wl3s at the inner ( 13). with up to 22 pemons inside. Air from this

unit is supplied to the distribution duct in theFor Medca: Aid Station us(. and perhaps roof of the van (l )via fle.itic duct 2). An

for Rest and Relief, where WW numbes of anti-back4•aft valve (32) is incorporated totroops would be peocewd through the van. ý.revmnt intpe of contaminants into thethe anterom (2$) would be attached by ante-•i.nm; Ance this valve is me4h+nical, nozipper (26). This tent-like structure is sup- connection to the control system i3 required.

REFERENCE

1. I. D. Rivers, K, L Wea3in. and R. J. Report. Amer. Air Filter Co.. Inc.. Louis-Boylan. Co&ctire Phorectlon for Corn- viilk. Kentucky. 4 May 1965 (AU%42.nwnd ?osr eikcleks. M292 Desgn S udy 50").

-A 0*ste*M -o "h AfAX *W fakM booawW 3 f ywý 1.

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GLOSSARY•

Absorption A process whereby a materal lower than that of the aMr. Coohlsn may bec tracts one or more sub.saces presnt in an accompanied by toisture addition (evapora-atmoiphere or nuxtur.e of ;m-, or fiqwds. tion), by moistur extraction (dehumidifica-a,:compamxe by physical change, chimcal tion), or by w; change whatever of rsiurrEchange, or both, of the materiaL content.

Actmuted Alurnwa. A form of aluminum AL Outdoor. Au taken frov- outdoe.s and.omde which adsorbs moisture readity 4nd n iherefore, nrot previously circulated throughused as a drying agent. the system.

Acttiated (ýzrbon. A form of carbon Inade Air. Saturated Moist air W which the partialporous by speciA treatment by which it is presare of the water vapor is equal to thecapable of adsorbing various odors, ancs,- vapor pressure of water at the existing tem-thetimcs and other vapors. perature. This occurs when dry air and satu-

rated water vapor coexist at the same dry-Adsorpton. The action, associated with sr- bulb temperature.face adherence, of a material in extracting oneor more substances present in an arBs e 77--Dnsh T0h-.d L: (BIt-. The Btu is de-or rmuxture of gwase and iquids, unac- fined as 778.177 foot-pounds. Approxi-zvi:ipanied by physical or chemical change. mately, it is the heat rquired ;C raiws tmrCommercial adsofrent materials have enor- temperature of a pound of water from 5 9 ' tomoos internal surfaces. 600F.

Air. An~bient. Generally speaking, the aii lofioe. Heat required to raise the tcmlpera-swrounding an object, ture of I graV of water I "C, actually from 4*

to 50 C. MWan calore = I. 100 pan of dth heatAir Circulation. Natural or mparted m otion required to naks I gram of watei( from 00 toof air. 10PC

Air Conditioner. An assembly of eouipment ColbIkca Protection. The protecton of anfor the control of at lest the first three items area and!or one or more pesonnel from tox i.enumerated in the defini*,n of air condi- aents used in Cemical-Bioiopca| w'arfaerioning-v without use of individual protection equip-

went.Air Conditioning The proces of treating airso as to control f-muhareously its tempera- Cnotsru A s-vrssi or arrngemren vs pipeture. humidity. c6-anhness. and distribution or tubing in whuch a vapor is hqtufxed bhto wnect the require-oents cf the conditioned rmoval ,f heat.space.

Drcibd. A unat used to express the relationAir Coolng Reduction in air temperaturr betwern two amounts of powr. B) defmitiondue to the abstraction :ýf heat as a eesult of the difference in decibels betvw,.n two"contact with a medium held at ; temperature rowem P3 and P2 . P2 bcir4 the Ulrgp. is dD

differenc = 10 log, ofF. 'P, . Used in acous-

W-ezemm P*iai. thrit fý bAVV bam aken ("M mr tit a~ Ta=Lmoloo %ASIIRM IAemdbok */ FISE'#

M (19P'. .Ouw A1nr. See Termperature. DJ.-Posnt

- CG-i


Em'ssiely. The capacity of a materaW to emit ft-lb per wc. or 33,OW( ft-lb Me mim.radiant enarg Emnittance is the ratio of thetow'l radiint flux emitted by a body t~o that lluntd~fy. To add waser vapor to the atmnos-emitted by an ideal blackbody at the sarm phcrt. to add wi'Ie vapor at moisture to anyteraperatuire matcrial.

Enthzalpy. Thernodynarnic property of a srb- Hrunddity Rn*,'. Wegt& of wataa vapozstanc defined as the sum of its internal (steam) asvsemted with one lb wcigh~t of d&yenerg plus the quantity PP/J. whie P = W,pressure of the substance, r =its volume. and

*J = G znemcharaical equivalent of heat. For- ftu~njdfi~r. Rdrswe. The ratio of the niolmerly called by the obsolescent nanms total ftaction of water vapor present in fte air, toheat and heat content. the mel fratio-n of Water vapor pftsent in

saturated air at the same temperature andEmporator. That part of a refuigmfai~g sys-, barometric presmure. approimately, it equalsttmn in which refiigerarf is vapotized to the ratio of the partial presure o: density ofproduce refrieration. the water vapoy in the air. to the saturation

pressure or density. rsecthvly. of waterExfifrnzrion. Aur flow outward through a vapor at the sare terrneratu~r.

hnch of W~ater. A unit of pressun equal to the[Failure Rate The number of fa~ircs of an pressure exerted by a co;%mm of bhquid wateItem per UV'Z MMeaUU of life (CYCles timne, I in. high at a temperature of 4"C or 39.2ZOF.miles, eients ewc, as applicable for the item).

inf*Irrtwm Air flo~wng inwad as thuough zcHear, Latent. Change of enirhalpy dutsin a w.All, crack, etc.change of state, With pure substanccs. !,atetmheat is absorbed or rejected at constant Load. Enwtaed Design. lin a heating orpress=-e cooling system., the sumn of the wefi-d hezV

transfer, plus htat trarafet from or to theHeat. Sensible. Heat which is aumoiated with connected pipin; z"~ ducwork. plus heata change in temperature; 4%ecific heat ex- tvansfer occurring in any a.zxffiary app~iatuschange of temperature; in 4contrast to a heat Connecird to thn system.interchange in which a% change of state (latentheat) occums Mnaitztlbiliry. A urch cigtsic of Orsign

=4d installation whiich is expressed as !hrHeat Pump. A refrigerating system eiaployed Mbreability that an item will be retained in orto tranfer heat into a space or substance. The resored to a2 secified condition within aIcondenser provides the heat wid~e the evapor- f~ven period of time. whlen the nmaitensncc t&ator a arranged to pik up heat from z;ir. peTiomwd wn accordance &-*:h prescrbed pro-water. etc. Bý shifting the flow of air or other cedures and resource&.fluid a heat purn', systemn may also be used tocool the sace. Mwrn-Maingenacc-TImer Thr gotal prk-sen-

ti-v anid conecwme n mm .~T- tunr dhvidcdlier: One he.rtz (Hz) eqtals I mp (adopte try, the total number of pre~ic-ntve and correc-.7 U ."a ~~cec n tre mainter-r a ctions durimg a spe-cifinWeights and Measures in Pzais. October, period of time,1960).

Akan- Tinw-Between-Pailurri ItfT8FJ. Foraho p~vrUnit of pover in foot-pound- Particular interval, the total functioning life

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tot al umwb Of (allUMe Wkio the poubtion cuting system in which thr e fft-cm~t aSuduring tCh eazumrernnt intemaL TIe dceni- evolvied in the evapowetr is takien upi, n antion twlds for time, cycles miles, events, or absorber and releawed in, a generaor upon theother nxeasure of tift unims app~ication of hwaL

IMean- TIme-Ta-Riepm-r (MTTRJ. The u"ta Retkalfty. The probability of a dc-ace per-corretmv maintenance time div"W by the for-lng its purpose adequately for the periodtotal number of malfunctsomb during a Omve of time intended under the opcrar',ag condi-

Perio of ~etions ecowuntmcd. For a syster, with mde-

Micon.A uit f lngt, he houandh pn penwd ent z copoents, te overal treliailiy i

Med%=aW Eqs-ekwof Het, Anprit and n to he broeuc0 of the rdvdati re he-wwrron ra.tion pc4i of117 time In Btu.h an Pries;ZYC of three sou de to reecmponent-,

item must perfotm a speciite aisin 90%e The bbt reee c c %rssrchal hbe i oeraiill

Mobil LMI Ayn wailt &wei Cewfabesr A inaatoO .9x(A9x0' 2V

fOm ne kcOaris e to Inte with- verysU little S eech wnillfex vc a overall (Skimbl ohfpec

ficme Ad efrit. Gf kmay cthe th uanith pis Skpxenercncc LcYW o oI-e ison thessrge.nmountedM oirectl odintho a m eter. vehcle ai n decibel is, of t -e sound ires -1e dle' s ofthe

be radie fo traspor ina fe hous. oaise i tho thre ocase 10ofth rti o f trhqen

.Modion Ant- ashemblyd oforming whihn ofem ofabsudt herfrm r

largerO fsebage, wtuch is n dei bed fo on Tmeawre ewPmndei ~aufmm oe repacemetos nit.herce vthe very tut Swhic thei~we Lee (SIDa~o owTher spor inamoadur uniet. modumary cntumtioe moular is sptacw beins ofo a gInie isthte of hunud itsmountendnce, monular mesr vet., ad a pr-eissu as the soundpeimure evl o f the ao

be radid fr trnsp ina fe hors.noredcd inhe theme ratur bands of nqenc t

of~m Ang bymanseomblytomangnetAcf wave ie bouehnd~a .osatp-ofW vseylnbge wareengh isdcgae. folr r citom- sue.wmr esPit Tetm~~ealkt-arehan: ener of auny t wavelnmthe teay, whenecodnanofwt. a-o rwuabsrbed. beomelz tconsructioenz anodsultr sep~~ace bem ora' c -si'tate of hnudit.. f

iwntan icrs moua em t.trmea the tempe~rature of the a a rrttreo ae ns aporJbsa~sorblng h~reiaccuraThe tlernmpcrtur xftrer-W-nd7ing to:Radiatn. herml!Rea). Th musissio satradation 00 ecn.eai un~ o

RafdgesenzeThe of any wavekid my, whefrneaaiowcyle, abecomben thmmt fro an resulci t Tempera w'c. DfecrihP Te A cnpcrbttrar ofd

temin inture. i h eprtr fte ap of tmixrture. humie- idityaned b-r aoeneaccurthe thermitonicof armth .-T -rctohi feto~th

Refifgenznintz7b Svxak, fluidpion a reffrig- hmnb' h ue~ au 4 o

ti~nc-yle.absobin hel (m a esecirt Te~emure Effcrie A arbtraý ith3


fth tieavalb or gol, SUMtw~ air Which aft of et bw ow per Oak as-t UN6&V *Nu4W044 k~ue un Mnidal ka g. m~ co.Won from the fluwi cc "M uw de of

3 t~o th "fdaItile ON iecýPaleu tTemnperairaer. Wet-M&Ab Thamiodyunaki aeu difference between the twowe24,ujb temIpuatue is the tempeclabi at fluids.which liquid or SOWd waler, by evaporatuttisto air, ca bow Owr ak to smxain rmit:ak . A fackity penenlly de-adiabaticdy at Wh suwn tempasimbe Wet- s~ped to be brought to a OMe lora*ic andbulb tewperatiwe (without w cainis remain for awaoths at a time. COasidcab*the tenperature uzmtd by a wet~bulb vaore time and effort ame needed to iEipOreaPsychrometer consructed and aped accomding Ou O unit than to prewe a iNWM~Ito specuitcations. mit fr~ shipmnent to a new kicsty. For

Throw~. The houizmtui oir vertiam U2I ds %be aisemblies (fer local poifamW buttance W & stream trWals att ksvgu an ar whc ,.vds a MI bed truck for UMotfoutkt before the maximum stum valociy n to-nw MWa over sevewa Milc awlay, isreduced to a soecifkd itiadaal leveL, ez., cndrdtmPUkl2W0, 150, 100, cc 50f(PaL

mmN. Down (Do"aWuln). That AlMent of UFactov. see: frMUWIUMCw. Ther."ULtimne &mg which the iefao tm n odtoto perform its intended functima Vemufikion Tbe process of npp~yiag or re-

nmovg aw, by ratural or mnechanica w&re,,Ton, of iRefi~gemroeL A useful a**~grafsig to or frow any space- Such air may or mayeffect equAg to 12.00 E#t per hr.; 200 Btu not have been cniind

Vokowe, *pdfic. The voluwe of a msubtanceTMM.uued.e Thenma (VI A*to). %Ce time per unit inux; the reciprocal of 'desity.

ASREVATIONS

Aim Airq MesWd Commnand HIEL Human Enp~ectr*n Labwratories

Cre hf;4kk PATOF Meart-7une-BtwceenFaitires

CSR nC4~-i~oARdA9 MTIRM M mrmst it

C' Cocsective Prtection UMT Mea-run-Th-Rex*

* aE C~ective Protection Equipnient QUM1 QuAitative Materie Dtvdopnmst0bdc

DA Departmient ofT the Army

ECU Enyviomental Control Unit QMR ialatatac Materiel Rcqsw==ets

GE Gwf%ý:nSI)R smn aI' iopienea Require eats

Owl) =*f~~aM ti Sit. Sound Psessmr Le~e1

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S(NCRM-TV) AMP 706-120

FOR THE CW WR: j4CKARLES T. HMER, JR.Kajor General. USAChief of Staff

OFFICIAL:

!lonel, GS!Q•-, A' in Wt Oft

DISTRIM ~ION:

Special

-I


II IENGINEERING DESIGN HANDBOOKS

"1 . l , ' , , i -k.. , ..

,

1• . . .*, 99 .

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Best Aaila.l Copy


SUPPLEMENTARY

IOT

INFORMATION


AMCP 706-120

DEPARTMENT OF THE ARMYHFADQUARTERS UNITED STATES ARMY MATERIEL COMMAND

5001 Eisenhower Ave, Alexandria, VA 22333

AMC PAMPHLET 19 ,June 1974No. 706-120

1 CHANGE 1

n Engineering Design Handbooks

CRITERIA FOR ENVIRONMENTAL CONTROL OF MOBILE SYSTEMS

AMCP 706-120, Engineering Design Handbook, Criteria for EnvironmentalControl of Mobile Systems, 16 September 1971, is changed as follows:

a. Paragraph 4-5(l), page 4-4, is changed to read:

(1) Mission reliability* of 95 percent with a missiontime of 24 hr with a 90 percent confidence

b. Paragraph 4-5(2), page 4-4, is changed to read:

A mean-time-between-failures* of 480 hr with90 percent confidence

(AMCRD-TV)

FOR THE COMMANDER:

OFFICIAL: JOSEPH W. PEZDIRTZ

Major General, USAChief of Staff

JOHN LYCASColonel, GSChief, HQ Admin Mgt Ofc

DISTRIBUTION:&Special


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