UNIVERSITI TEKNIKAL MALAYSIA MELAKA

INVESTIGATION OF MULTIPLE COOLING COIL EFFECT IN

HYDRONIC RADIANT COOLING SYSTEM FOR AIR

HANDLING UNIT (AHU) PURPOSES

This report is submitted in accordance with the requirement of Universiti Teknikal

Malaysia Melaka (UTeM) for the Bachelor Degree of Engineering Technology

(Refrigeration and Air Conditioning System) with Honours

by

MUHAMMAD HAZWAN BIN ROSSLI

B071310394

911019-14-6593

FACULTY OF ENGINEERING TECHNOLOGY

2016

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS LAPORAN PROJEK SARJANA MUDA

TAJUK: INVESTIGATION OF MULTIPLE COOLING COIL EFFECT IN HYDRONIC RADIANT COOLING SYSTEM FOR AIR HANDLING UNIT PURPOSES SESI PENGAJIAN: 2015/16 Semester 1 Saya MUHAMMAD HAZWAN BIN ROSSLI mengaku membenarkan Laporan PSM ini disimpan di Perpustakaan Universiti Teknikal Malaysia Melaka (UTeM) dengan syarat-syarat kegunaan seperti berikut:

1. Laporan PSM adalah hak milik Universiti Teknikal Malaysia Melaka dan penulis. 2. Perpustakaan Universiti Teknikal Malaysia Melaka dibenarkan membuat salinan

untuk tujuan pengajian sahaja dengan izin penulis. 3. Perpustakaan dibenarkan membuat salinan laporan PSM ini sebagai bahan

pertukaran antara institusi pengajian tinggi.

4. **Sila tandakan ( )

TERHAD

SULIT

TIDAK TERHAD

(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia sebagaimana yang termaktub dalam AKTA RAHSIA RASMI 1972)

(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan)

Alamat Tetap:

No 6, Jalan 16/3C

Taman Cheras Jaya, Batu 9 Cheras

43200 , Selangor Darul Ehsan.

Tarikh: ________________________

Disahkan oleh:

Cop Rasmi: Tarikh: _______________________

** Jika Laporan PSM ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasa/organisasi berkenaan dengan menyatakan sekali sebab dan tempoh laporan PSM ini perlu dikelaskan sebagai SULIT atau TERHAD.

DECLARATION

I hereby, declared this report entitled

“Investigation of Multiple Cooling Coil Effect in Hydronic Radiant Cooling

System for Air Handling Unit (AHU) purposes”

is the results of my own research except as cited in references.

Signature : …………………………………………..

Author’s Name: MUHAMMAD HAZWAN BIN ROSSLI

Date : 9 DECEMBER 2016

APPROVAL

This report is submitted to the Faculty of Engineering Technology of Universiti

Teknikal Malaysia Melaka (UTeM) as a partial fulfillment of the requirements

for the degree of Bachelor of Mechanical Engineering Technology

(Refrigeration & Air-Conditioning Systems) (Hons.). The member of the

supervisory is as follow:

………………………………

(Mr. Amir Abdullah Bin Muhamad Damanhuri)

i

ABSTRAK

Unit pengendalian udara adalah alat yang digunakan untuk mengawal dan

mengedarkan udara sebagai sebahagian daripada sistem “Heating, Ventilating and

Air Conditioning (HVAC)”. Komponen utama dalam unit pengendalian udara adalah

kipas, elemen penyejukan dan pemanasan, alat pelembab, rak penapis, pengurang

bunyi dan peredam. Sistem ini kebiasaannya disambungkan ke salur udara yang

membekalkan udara dingin pada bangunan. Sumber penyejukan di unit pengendalian

udara dihasilkan oleh sistem penyejuk yang menggunakan air dan bahan pendingin

sebagai media pengangkutan. Penggunaan bahan pendingin mempunyai kesan yang

ketara kepada alam sekitar dan lapisan ozon. Tambahan pula, pemampat

menggunakan banyak tenaga elektrik untuk memampatkan bahan pendingin ke

dalam sistem. “Hydronic Cooling Radiant (HRC)” adalah salah satu sistem alternatif

yang menghasilkan air sejuk sebagai media pengangkutan. Sistem ini telah

digunakan di negara-negara barat. Di samping itu, sistem ini juga boleh membantu

mengurangkan penggunaan elektrik kerana ia hanya menggunakan pam untuk

membekalkan air sejuk. Di unit pengendalian udara, kipas menggunakan hampir

40% daripada jumlah tenaga elektrik di dalam sistem. Oleh itu, pemilihan kipas perlu

dipertimbangkan di dalam kajian semasa. Pembelajaran ini hanya memberikan

tumpuan kepada prestasi unit pengendalian udara dan menerangkan kebarangkalian

menggunakan sistem HRC di Malaysia. Data yang diperolehi akan diperhatikan dan

dianalisis untuk mengukur prestasi dengan membandingkan parameter yang memberi

kesan pada sistem unit pengendalian udara. Suhu dan kelembapan untuk mencapai

keselesaan di Malaysia adalah di antara 23°C hingga 26°C dan 30% kepada 60%.

Rekabentuk, fabrikasi dan eksperimen projek telah dibentangkan.

ii

ABSTRACT

The Air Handling Unit system is a device used to control and circulate air as part of

Heating, Ventilating and Air Conditioning system (HVAC).The major components in

Air Handling unit are fan, cooling and heating element, humidifier, filter racks,

sound attenuator and damper. The system usually connect to a ductwork that supply

the conditioned air through the building. The cooling sources in Air Handling Unit

are delivered by a chiller that use water and refrigerant as medium transport. The use

of refrigerant had a significant impact on environment and ozone layer. Furthermore,

compressor use a lot of electricity to compress a refrigerant into the system.

Hydronic Radiant Cooling is an alternative system that produce cold water as a

medium transport. The system has been used in western countries. In addition, the

system also can help to reduce electrical consumption because it only use pump to

supply cold water. In Air Handling Unit, fan use almost 40% of total electricity in the

system. So that, the selection of fan must be considered .This current study focus on

the performances of Air Handling Unit and describes the possibility of using

Hydronic Radiant Cooling in Malaysia. The data obtained were observed and

analysed to measure the performance by comparing the effective parameter in Air

Handling Unit. The temperature and relative humidity for thermal comfort to be

achieve in Malaysia are between 23°C to 26°C and 30% to 60%. Design, fabrication

and experimental of the project are presented.

iii

DEDICATION

To my beloved parents, Rossli Bin Yusoff and Saodah Binti OthmanI acknowledge

my sincere indebtedness and gratitude to them for their love, dream and sacrifice

throughout my life. I am really thankful for their sacrifice, patience, and

understanding that were inevitable to make this work is possible. Their sacrifice had

inspired me from the day I learned how to read and write until what I have done now.

I cannot find the appropriate words that could properly describe my appreciation for

their devotion, support and faith in my ability to achieve my dreams comes true

Lastly, I would like to send my gratitude to any person that contributes to my final

year project whether it is directly or indirectly. I would like to acknowledge their

comments and suggestions, which are crucial for the successful completion of this

current studies.

iv

ACKNOWLEDGEMENT

I wish to thank my faculty members who were more than generous with their

expertise and precious time. A special thanks to Mr Amir Abdullah Bin Muhamad

Damanhuri, my supervisor for his countless hours of reflecting, reading,

encouraging, teaching and most of all patience throughout the entire process. Thank

you to my bachelor degree project teammates, Muhammad Ridzuan Bin Pawanteh

for completing the project together. I would like to acknowledge and thank to my

university faculty and library for allowing me to conduct my project and providing

amy assistance requested. Special thanks goes to the members of staff from the

Factory 2 in Universiti Teknikal Malaysia Melaka (UTeM) for their continued

support. Finally, I would like to thank my academic advisor, Mr Mohd Harris

Fadhilah Bin Zainudin for always assisted me to complete this current project. Their

excitement and willingness to provide feedback made the completion of this project

an enjoyable experiences.

v

TABLE OF CONTENT

Abstrak i

Abstract ii

Dedication iii

Acknowledgement iv

Table of content v

List of Tables viii

List of Figures ix

List of Abbreviations, Symbols and Nomenclature xi

CHAPTER 1 INTRODUCTION

1.1 Background of the study 1

1.2 Problem Statement 3

1.3 Objective 4

1.4 Scope of Work 4

1.5 Thesis Outline 5

CHAPTER 2 LITERATURE REVIEW

2.1 Central Air Conditioning Cycle 6

2.1.1 Air Conditioning and Global energy demand 7

2.2 Air Handling Unit 9

2.2.1 Air Handling Unit Performances 10

2.2.2 Energy Consumption 11

2.3 Fan 12

2.3.1 Fan Selection 12

2.4 Cooling Coil 13

2.4.1 Coil placement inside the Air Handling Unit 14

2.5 Hydronic Radiant Cooling System 14

2.5.1 Hydronic Radiant Cooling System definition 15

2.5.2 History of Hydronic Radiant Cooling System 15

vi

2.5.3 Types of Hydronic Radiant Cooling System 16

2.5.4 Limitation 17

2.5.5 Energy Consumption of Hydronic Radiant Cooling System 17

2.5.6 Comparison between Hydronic Radiant Cooling and Air- 18

Conditioning System

2.6 Silica Gel 18

2.6.1 Absorbing and Removing Moisture 19

CHAPTER 3: METHODOLOGY

3.1 Flow chart 21

3.2 Design and preparation of prototype 22

3.3 Fabrication Process 23

3.3.1 Selection of Component and Material 23

3.3.2 Selection of Equipment 32

3.3.3 Procedures 33

3.4 Experimental Process 41

3.4.1 First experiment (Water temperature) 41

3.4.2 Second experiment (Effect of distance on temperature output 42

with single coil)

3.4.3 Third experiment (Effect of number of row cooling coil on the 43

temperature output)

3.4.4 Experimental Equipment 44

3.4.5 Experimental Procedure 46

CHAPTER 4 RESULT AND DISCUSSION

4.1 Result 49

4.1.1 Experiment 1: Effect of amount sodium chloride to water 50

Temperature

4.1.2 Experiment 2: Effect of Distance of Cooling Coil on temperature 53

Output

4.1.3 Experiment 3: Effect of Number Cooling Coil on temperature 59

Output

vii

4.2 Coefficient of Performances (COP) 64

4.3 Efficiency of the system 68

CHAPTER 5 CONCLUSION AND RECOMMENDATION

5.1 Summary of the Project 70

5.2 Achievement of Project Objective 71

5.3 Future Development 72

REFERENCES 73

APPENDICES 76

viii

LIST OF TABLES

2.1 Typical coil air pressure drop 13

3.1 List of Equipment functions 32

3.2 Amount of Sodium Chloride 41

3.3 Experimental Procedure Process 46

4.1 Effect of amount ice cube to water temperature 50

4.2 Effect of amount Sodium Chloride (NaC1) to water temperature 52

4.3 List of data for single cooling coil with lower fan speed 53

4.4 List of data for single cooling coil with medium fan speed 54

4.5 List of data for single cooling coil with maximum fan speed 54

4.6 List of data for double cooling coil with maximum fan speed 59

4.7 List of data for triple cooling coil with maximum fan speed 60

4.8 Result of COP and Efficiency for difference number of cooling coil 69

ix

LIST OF FIGURES

2.1 Central system cycle 7

2.2 Energy usage of equipment in HVAC system 8

2.3 Air Handling Unit Flow 10

3.1 Flow Chart 21

3.2 Schematic diagram of complete system 22

3.3 Acrylic Sheet 23

3.4 Axial AC fan 24

3.5 Proton Waja Cooling Coil 24

3.6 Copper tube 25

3.7 AC water pump 25

3.8 Silica Gel 26

3.9 Insulator 26

3.10 Hollow Metal Bar 27

3.11 Zinc sheet 27

3.12 PVC Pipe 28

3.13 L bracket 28

3.14 Threaded Metal Bar 29

3.15 Plastic container box 29

3.16 Screw and Nut 30

3.17 Plywood 30

3.18 Fan Regulator 31

3.19 Electrical box 31

3.20 Schematic diagram of 3 cases (Effect of Distance on temperature output) 42

3.21 Schematic diagram of 2 cases (Effect of number of row cooling coil on 43

the temperature output)

3.22 Thermometer Fluke 44

3.23 RH data logger 45

3.24 Anemometer 45

x

4.1 Graph of water temperature vs amount of ice cube 51

4.2 Graph of water temperature vs amount of sodium chloride 52

4.3 Graph of temperature outlet vs distance cooling coil from fan 55

4.4 Graph of relative humidity vs distance cooling coil from fan 56

4.5 Graph of air flowrate vs distance cooling coil from fan 57

4.6 Graph of air velocity vs distance cooling coil from fan 57

4.7 Graph of water temperature vs distance cooling coil from fan 58

4.8 Graph of effect of number cooling coil on air temperature 60

4.9 Graph of effect of number cooling coil on relative humidity 61

4.10 Graph of effect of number cooling coil on air flowrate 62

4.11 Graph of effect of number cooling coil on air velocity 62

4.12 Graph of number cooling coil on water outlet temperature 63

xi

LIST OF ABBREVIATIONS, SYMBOLS AND

NOMENCLATURE

A Ampere/Area

AC Alternate Current

AHU Air Handling Unit

C Celsius

Cfm Cubic feet per minute

COP Coefficient of Performances

Cp Specific Heat

F Fahrenheit

Ft Feet

Fpm Feet per minute

HRC Hydronic Radiant Cooling

h Height

HVAC Heating, Ventilating and Air Conditioning

Hz Hertz

Inch Inches

Kg Kilogram

Kw Kilowatt

L Litre

l Length

m Meter

ṁ Mass flow rate

NaC1 Sodium Chloride

PVC Polivinyl Chloride

RH Relative Humidity

Rpm Rotation per minute

USB Universal Serius Bus

Q Heat

TR Temperature

xii

V Voltage/Velocity

W Width

ɳ Efficiency

ρ Density

≤ Less than or equal to

1

CHAPTER 1

INTRODUCTION

The current chapter introduces the most important subtitles related to the

project. However, the subtitles are the plan and the basic topics, which include

background of the study, problem statement, objectives, scope of the project and

thesis outline.

1.1 Background of the study

Air-conditioning is the process of treating the temperature, relative humidity,

provide clean air and distribute it into the building space. In thousand years ago,

several ancient architectural already studies cooling technique for controlling

building temperature to local climate such as thermal conductivity of material, high

room ceilings and shading. The first modern air-conditioning system was created in

1902 by a 25 years old engineer named Willis Carrier. Nowadays, conventional air

conditioning become an important device. It’s mainly used in building over the world

such as for residential, industrial and commercial. The main purpose of air-

conditioning system is to provide thermal comfort and improving indoor air quality

(IAQ) for occupants. The application of air conditioning in daily live allows people

to feel comfortable especially in Malaysia that is known as a hot and humid climate

condition. By lowering the occupied zone temperature, vapour compression cycle are

commonly used in air conditioning system to achieve thermal comfort for human use

(Regnier, 2012).

2

In recent years, a system that provide more comfortable thermal environment

than conventional all-air system has been created. The system is designed to reduce

energy consumption in the line with current modern technology. An alternative

system is called Hydronic Radiant Cooling (HRC) which is using water as the

transport medium(Colorado, 2010). It is becomes one of the significant solutions

since it is able to reduce amount of air distribute in the buildings. HRC is normally

install in ceiling, wall and building floor. Unlike the conventional air conditioning

system, HRC does not use a vapour compression cycle that consume 40% of the total

electrical consumption in the world (Westphalen, Koszalinski, & Little, 1999). Cold

water are used to replace refrigerant gas as a cooling medium that is unlimited

source, cheapest and also environmental friendly. The natural cooling provided by

HRC is more acceptable range for thermal comfort.

In this current study, an Air Handling Unit (AHU) which are used in air-

conditioning system will be design, fabricate in prototype and tested the application

for cooling in Malaysia. HRC are connected to cooling coil to supply cold water as a

cooling sources. Fan are required in AHU which performs the function of force and

recycling the air present in the building space. The second important components of

an AHU are the cooling elements which are used to allow cold water flow into the

air-conditioning systems. The distance between fan and cooling coil, number of row,

and oriental of the design must be considered because it will affect the AHU

performances (A. P. Guide et al 1998). Selection of material for AHU casing are also

are important parts to prevent heat loss and the types of insulation are selected. Drain

pan are attached below the cooling coil to catches the condensate that drips off at the

outside of the coil as the warm moist air passes over the coil. The cold water in the

coil cooled the air and causing the moisture to condense on the outside of the coil.

In fact, the characteristics of the plastic container are to keep store heat

because it will minimize heat transfer due to conduction and radiation process. So

that, it will be selected to ensure the ice cubing in HRC system is durable. In order to

lowering the temperature as needed , salt is added to the cold water and it will cause

a temperature drop that slows the melting rate and increases the freezing rate. Pump

are used to force the cold water into the cooling coil. The data that will be taken in

3

consideration are output temperature and also relative humidity for controlling the

humidity of the conditioned space. In order to control the humidity and dry bulb

temperature, silica gel material is placed after cooling coil where the air inlet is

supplied. Therefore, the experimental work will be carried out to confirm the

suitability of this application in Malaysia.

1.2 Problem Statement

Hot climate in Malaysia led many building use air conditioning for comfort.

The total energy consumption increase and cause a large impact on economy. Most

of the existing air-conditioning in the market using vapour compression cycle

compared to absorption cycle. Compressor is one of the basic components in the

vapor compression cycle and it is assigned to compress the refrigerant into the

system. It requires a high energy consumption to operate. It also generates noise and

vibrations in the system that requires maintenance and this increase the annual cost.

Vapor compression cycle use a refrigerants as a medium transportation which

absorb and remove heat from a space to be cooled. These can be less environmental

friendly as they require refrigerants for emission. This current study is looking for an

alternative source of cooling associate with AHU with less energy consumption to be

assigned which focusing on Hydronic Radiant Cooling system associated with AHU

is the challenge.

4

1.3 Objective

In this current project, some targets has been select to focus on the studied.

Therefore, the main objective of the current project are:

a) To study the possibilities of using Hydronic Radiant Cooling (HRC) as an

alternative cooling system for Malaysia climate

b) To develop a prototype of Air Handling Unit to apply Hydronic Radiant Cooling

in achieving desired temperature

c) To compare multiple row of cooling coil in demonstrate temperature and relative

humidity data by applying silica gel.

1.4 Scope of Work

Commercial businesses play a role at reducing costs and energy

consumption through a heating, ventilation and air conditioning (HVAC).This

study focus on enhancement the performances of Hydronic Radiant Cooling system

in hydronic tank that has been develop. The scope of this current study is the part in

AHU that includes multiple row of cooling coil and the distance between fan and

cooling coils. In addition, cold water supply in container box is also will be

considered. The working process only considered at enclosed place to maintain its

surrounding temperature.

5

1.5 Thesis Outline

This report has been divided into five chapters. The chapter includes are

introduction, literature review, methodology, results and analysis, conclusion and

recommendation. Chapter 1 contains background of the study, problem statement,

objective, and scope of work. Chapter 2 written about the previous studies and

research related to this project. Chapter 3 presents the Methodology of this project

which include the materials used, equipment’s, fabrication, and procedures. In

Chapter 4, indicates all results and discussion with analysis of the project. The result

of the project has been discussed in detail within this chapter. Lastly, in chapter 5

shows the explanations about the conclusion and recommendations for future works

is presented.

6

CHAPTER 2

LITERATURE REVIEW

Present literature review is summarized to survey topics that have more

relevant to current study. The most important subtopics summarized for current

Literature review are background, Air Handling Unit, fans, cooling coils, Hydronic

radiant cooling system, acrylic and silica gel.

Therefore the background for current project is carried out and summarized to

understand the basic idea of air conditioning system. Central air conditioning cycle is

the attractive example which used in wide space. Air Conditioning and Global

energy demand is considered as well.

2.1. Central Air Conditioning Cycle

Central air conditioning cycle is an air conditioning system. However, it uses

a series of equipment’s to distribute cooling media to exchange heat and supply

conditioned air from one point to more than one rooms. Normally water is used as

the cooling media for larger buildings. Central air conditioning cycle is a process of

removing heat content from multiple sources in the building through a series of heat

exchange equipment which ultimately remove the heat to outdoor atmosphere. Once

the air is being cooled, the AHU must distribute it throughout the building. AHU

supplies the cooled and dehumidified air to the conditioned space and returns it back

into the facility .Cooling towers are heat rejection devices used to transfer process

waste heat to the atmosphere. Cooling towers may either use the evaporation of

water to reject process heat and cool the working fluid to near the wet-bulb air

7

temperature or rely solely on air to cool the working fluid to near the dry-bulb air

temperature (Christiansen, 2007). The arrangement of Central system cycle is shown

in Figure 2.1.

Figure 2.1: Central system cycle

2.1.1 Air Conditioning and Global energy demand

Heating, ventilating, and air conditioning (HVAC) consumes almost

31% of the total electricity compared with lighting and other applications that

use electricity as a main source(Kusiak & Li, 2010). HVAC is widely used in

building with hot and humid climate conditions like Malaysia. Many air

conditioned spaces in largest building such as, hotel, office and shopping mall

have lower temperature setting to compensate for inadequate air distribution

in some areas (Yap et al., 2011). Figure 2.2 illustrates energy usage of

equipment in HVAC system.

8

Figure 2.2: Energy usage of equipment in HVAC system

Using supply and return fans consume huge amount of energy

compared to the other applications, because it used in almost 100% of

system types as defined in (Westphalen et al., 1999) and as reported that.

Normally, air distribution design resulting considerable pressure drop for

filtration, cooling and heating coils, terminal boxes, and diffusers, and many

of these fans operate at 100% power during all building operating hours

Improvements in equipment efficiency can help to reduce in building

operating costs. Energy conservation in buildings is important because

HVAC system is one of the primary energy users in buildings. Efficiency of

AHU and air distribution systems can save amounts of energy, reduce

operating costs and comply with widely used energy standards (ASHRAE

Standard 90.1 2004) and building codes. The electricity sector involves the

generation, transmission, and distribution of electricity. Carbon dioxide (CO2)

makes up the most of the greenhouse gas emissions from the sector, but

smaller amounts of methane (CH4) and nitrous oxide (N2O) are also emitted.

These gases are released during the combustion of fossil fuels, such as coal,

oil, and natural gas, to produce electricity. Buildings produce to about 30% of

the total greenhouse gases emissions, and the proportion has been increasing

to the level of the developed counties (Yun et al., 2014) .