MECH 351 - Encskadem/MECH 351/W2019/LABS/ME… · mech 351 laboratory manual (winter 20 1 9):...

THERMODYNAMICS II H 1063

MECH 351 LABORATORY MANUAL

(WINTER 2019)

GINA CODY SCHOOL OF ENGINEERING AND COMPUTER SCIENCE

Department of Mechanical,Industrial and Aerospace Engineering

EMERGENCY • URGENCESecurity 514-848-(3717) Sécurité

BUILDING EVACUATIONWhen you hear the fire alarm, YOU MUST LEAVE THE BUILDING IMMEDIATELY.

1. Stop your work.2. Gather all your personal

belongings.3. Calmly leave the room, closing

doors and windows behind you, and go to the nearest emergency exit door or stairwell.

4. Once outside, move away from the building.

Help mobility impaired people

If you encounter a mobility impaired person that can not use the emergency stairwells during an evacuation, the following procedure must be used:

1. Escort the person to the nearest emergency stairwell, remaining outside the stairwell.

2. Use a telephone (Fire Department, emergency or cellular) to contact Security and advise them that you are with a disabled person; if not available, send somone to advise Security.

3. Security personnel or Emergency Responders (CERT members) will come to assist you.

4. In the presence of danger, such as smoke, alert Security and move the person inside the stairwell ensuring the door is closed behind you.

ÉVACUATION DES LIEUXDès que vous entendez l’alarme incedie, QUITTEZ LE BÂTIMENT IMMÉDIATEMENT.

1. Cessez toute activité.2. Rassemblez vos effets personnels.3. Quittez la salle dans le calme, en

fermant les portes et fenêtres derrière vous, et dirigez-vous vers l’escalier ou l’issue de secours le plus proche.

4. Une fois à l’extérieur, éloignez-vous du bâtiment.

Aidez aux personnes à mobilité réduite

Si vous rencontrez une personne à mobilité réduite qui ne peut utiliser les escaliers de secours pendant l’évacuation, suivez cette procédure:

1. Accompagnez-la jusqu’à l’escalier de secours le plus proche en demeurant à l’extérieur de la cage d’escalier.

2. Utilisez un téléphone (service des incendies, urgence ou cellulaire) ou dépêches quelqu’un pour aviser la Sécurité que vous êtes avec une personne à mobilité réduite.

3. Attendez que le personnel de la Sécurité ou les intervenants d’urgence viennent vous aider.

4. S’il y a présence d’un danger (de la fumée, par example), contactez la Sécurité et emmenez la personne à l’intérieur de la cage d’escalier en vous assurant de refermer la porte derrière vous.

concordia.ca/emergency

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TABLE OF CONTENTS

CONTACTS ii

LABORATORY CALENDAR iii

ACKNOLWEDGMENTS iv

GENERAL LABORATORY SAFETY RULES v

LABORATORY PROTOCOL viii

LABORATORY REPORTS x

1. STIRLING ENGINE 1

Introduction 2 Equipment 5 Theory 11

References 12

EXERCISE A: MEASURING MECHANICAL

POWER (SETUP #1) 13

EXERCISE B: MEASURING ELECTRICAL POWER (SETUP #2) 14

EXERCISE C: SOLAR STIRLING ENGINE (SETUP #3) 15

EXERCISE D: STIRLING ENGINE AS A HEAT PUMP (SETUP #4) 16

Data Sheet 17

2. CYCLEPAD 21 Introduction 22 Analyzing Our Design 23 Finishing the Problem 27 Problems 28 References 28

3. REFRIGERATION 29

EXERCISE A: BUILD A LOW COST AIR CONDITIONER 30

Introduction 30 Materials 30

Procedure 31 References 36

EXERCISE B: ROOM AIR CONDITIONER ANALYSIS 37

Introduction 37 Apparatus 39

Theory 39 Procedure 46 Results 46

References 46 Data Sheet 49

4. AIR CONDITIONING UNIT 51 Introduction 52 Description 53 Operation & Software 59 Specifications 63 Background & Theory 65 References 70

EXERCISE A: PSYCHOMETRIC CHARTS 71 Equipment Set-up 71 Procedure 71 Results 71

EXERCISE B: SENSIBLE HEATING 72 Theory 72 Equipment Set-up 73 Procedure 74 Results 74

EXERCISE C: HUMIDIFICATION 75 Theory 75 Equipment Set-up 75 Procedure 75 Results 76

Data Sheet 77

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CONTACTS

LABORATORY INSTRUCTOR (Fill in by student)

Name: _____________________________________________________________________________

E-Mail: _____________________________________________________________________________

Office: _____________________________________________________________________________

Phone: _____________________________________________________________________________

Lab Section: ______________ Lab Day & Time: __________________________ Week: ________

LABORATORY PARTNERS (Fill in by student)

Name: _____________________________________________________________________________

E-Mail: _____________________________________________________________________________

Phone: _____________________________________________________________________________

Name: _____________________________________________________________________________

E-Mail: _____________________________________________________________________________

Phone: _____________________________________________________________________________

Name: _____________________________________________________________________________

E-Mail: _____________________________________________________________________________

Phone: _____________________________________________________________________________

LABORATORY COORDINATOR Name: Petre Tzenov E-Mail: [email protected] Office: EV 004.183 Phone: 514-848-2424 x8670

LABORATORY TECHNICIANSName: Dave Chu Henry Szczawinski E-Mail: [email protected]/ [email protected]: H 1061/EV S3.419Phone: 514-848-2424 x3199/x2984

LABORATORY SPECIALISTName: Peter SakarisE-Mail: [email protected]: H 1047Phone: 514-848-2424 x3153

TECHNICAL/SAFETY OFFICERName: Robert OliverE-Mail: [email protected]: H 1062Phone: 514-848-2424 x8797

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LABORATORY CALENDAR Laboratory Calendar is subject to change after time of printing this manual.

MON TUES WED THURS FRI

JAN

UA

RY

WE

EK

1 7 8 9 10 11

WE

EK

2 14Lab TJ-X: 8:45-10:35Lab TR-X: 10:45-12:35Lab TM-X: 12:45-14:35Lab TT-X: 15:45-17:35

15Lab TN-X: 8:45-10:35Lab TO-X: 10:45-12:35

16Lab XJ-X: 8:45-10:35Lab TV-X: 12:45-14:35Lab TX-X: 14:45-16:35

17Lab XO-X: 8:45-10:35Lab XM-X: 10:45-12:35Lab XP-X: 14:45-16:35

18Lab XQ-X: 8:45-10:35Lab XR-X: 11:45-13:35Lab TF-X: 14:45-16:35

EX

PER

IME

NT

1

WE

EK

1 21Lab TI-X: 8:45-10:35Lab TK-X: 10:45-12:35Lab TL-X: 12:45-14:35Lab TS-X: 15:45-17:35

22Lab TG-X: 8:45-10:35Lab TH-X: 10:45-12:35

23Lab XI-X: 8:45-10:35Lab TU-X: 12:45-14:35Lab XK-X: 14:45-16:35

24Lab TP-X: 10:45-12:35Lab XN-X: 14:45-16:35Lab XS-X: 16:45-18:35

25Lab TQ-X: 8:45-10:35Lab TW-X: 10:45-12:35Lab TE-X: 14:45-16:35

FEB

RU

ARY

WE

EK


29Lab TN-X: 8:45-10:35Lab TO-X: 10:45-12:35




EX

PER

IME

NT

2(H

841)

WE

EK


5Lab TG-X: 8:45-10:35Lab TH-X: 10:45-12:35




WE

EK


12Lab TN-X: 8:45-10:35Lab TO-X: 10:45-12:35




EX

PER

IME

NT

3

WE

EK

1 18 Lab TI-X: 8:45-10:35Lab TK-X: 10:45-12:35Lab TL-X: 12:45-14:35Lab TS-X: 15:45-17:35

19 Lab TG-X: 8:45-10:35Lab TH-X: 10:45-12:35


21 Lab TP-X: 10:45-12:35Lab XN-X: 14:45-16:35Lab XS-X: 16:45-18:35


BR

EA

K 25 26 27 28 1 BR

EA

K

MA

RC

H

WE

EK


5Lab TN-X: 8:45-10:35Lab TO-X: 10:45-12:35




EX

PER

IME

NT

4

WE

EK


12Lab TG-X: 8:45-10:35Lab TH-X: 10:45-12:35




WE

EK

2 188:00-15:45(Technician available)

198:00-15:45(Technician available)




MIC

RO

STE

AM

CA

R PR

OJE

CT

(ALL LA

B SE

CT

ION

S)

WE

EK






APR

IL

WE

EK

2 18:00-16:00First Qualifying Session (Day 1)





WE

EK

1 88:00-16:00First Qualifying Session (Day 2)



118:00-16:00Second Qualifying Session

12

159:30-12:00MICRO STEAM CAR COMPETITION(H 1065/H 1067)

16 17 18 19

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ACKNOWLEDGMENTS Design and layout of this manual are made possible thanks to Véronique Verthuy and Marc Bourcier, part of University Communications Services, Concordia University.

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v

GENERAL LABORATORY SAFETY RULES

FOLLOW RELEVANT INSTRUCTIONS

• Before attempting to install, commission or operate equipment, all relevant suppliers’/manufacturers’ instructions and local regulations should be understood and implemented.

• It is irresponsible and dangerous to misuse equipment or ignore instructions, regulations or warnings.

• Do not exceed specified maximum operating conditions (e.g. temperature, pressure, speed etc.).

INSTALLATION/COMMISSIONING

• Use lifting table where possible to install heavy equipment. Where manual lifting is necessary beware of strained backs and crushed toes. Get help from an assistant if necessary. Wear safety shoes where appropriate.

• Extreme care should be exercised to avoid damage to the equipment during handling and unpacking. When using slings to lift equipment, ensure that the slings are attached to structural framework and do not foul adjacent pipe work, glassware etc.

• Locate heavy equipment at low level.

• Equipment involving inflammable or corrosive liquids should be sited in a containment area or bund with a capacity 50% greater than the maximum equipment contents.

• Ensure that all services are compatible with equipment and that independent isolators are always provided and labelled. Use reliable connections in all instances, do not improvise.

• Ensure that all equipment is reliably grounded and connected to an electrical supply at the correct voltage.

• Potential hazards should always be the first consideration when deciding on a suitable location for equipment. Leave sufficient space between equipment and between walls and equipment.

• Ensure that equipment is commissioned and checked by a competent member of staff permitting students to operate it.

OPERATION

• Ensure the students are fully aware of the potential hazards when operating equipment.

• Students should be supervised by a competent member of staff at all times when in the laboratory. No one should operate equipment alone. Do not leave equipment running unattended.

• Do not allow students to derive their own experimental procedures unless they are competent to do so.

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MAINTENANCE

• Badly maintained equipment is a potential hazard. Ensure that a competent member of staff is responsible for organizing maintenance and repairs on a planned basis.

• Do not permit faulty equipment to be operated. Ensure that repairs are carried out competently and checked before students are permitted to operate the equipment.

ELECTRICITY

• Electricity is the most common cause of accidents in the laboratory. Ensure that all members of staff and students respect it.

• Ensure that the electrical supply has been disconnected from the equipment before attempting repairs or adjustments.

• Water and electricity are not compatible and can cause serious injury if they come into contact. Never operate portable electric appliances adjacent to equipment involving water unless some form of constraint or barrier is incorporated to prevent accidental contact.

• Always disconnect equipment from the electrical supply when not in use.

AVOIDING FIRES OR EXPLOSION

• Ensure that the laboratory is provided with adequate fire extinguishers appropriate to the potential hazards.

• Smoking must be forbidden. Notices should be displayed to enforce this.

• Beware since fine powders or dust can spontaneously ignite under certain conditions. Empty vessels having contained inflammable liquid can contain vapor and explode if ignited.

• Bulk quantities of inflammable liquids should be stored outside the laboratory in accordance with local regulations.

• Storage tanks on equipment should not be overfilled. All spillages should be immediately cleaned up, carefully disposing of any contaminated cloths etc. Beware of slippery floors.

• When liquids giving off inflammable vapors are handled in the laboratory, the area should be properly ventilated.

• Students should not be allowed to prepare mixtures for analysis or other purposes without competent supervision.

HANDLING POISONS, CORROSIVE OR TOXIC MATERIALS

• Certain liquids essential to the operation of equipment, for example, mercury, are poisonous or can give off poisonous vapors. Wear appropriate protective clothing when handling such substances.

• Do not allow food or drink to be brought into or consumed in the laboratory. Never use chemical beakers as drinking vessels

• Smoking must be forbidden. Notices should be displayed to enforce this.

• Poisons and very toxic materials must be kept in a locked cupboard or store and checked regularly. Use of such substances should be supervised.

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AVOID CUTS AND BURNS

• Take care when handling sharp edged components. Do not exert undue force on glass or fragile items.

• Hot surfaces cannot, in most cases, be totally shielded and can produce severe burns even when not visibly hot. Use common sense and think which parts of the equipment are likely to be hot.

EYE/EAR PROTECTION

• Goggles must be worn whenever there is risk to the eyes. Risk may arise from powders, liquid splashes, vapors or splinters. Beware of debris from fast moving air streams.

• Never look directly at a strong source of light such as a laser or Xenon arc lamp. Ensure the equipment using such a source is positioned so that passers-by cannot accidentally view the source or reflected ray.

• Facilities for eye irrigation should always be available.

• Ear protectors must be worn when operating noisy equipment.

CLOTHING

• Suitable clothing should be worn in the laboratory. Loose garments can cause serious injury if caught in rotating machinery. Ties, rings on fingers etc. should be removed in these situations.

• Additional protective clothing should be available for all members of staff and students as appropriate.

GUARDS AND SAFETY DEVICES

• Guards and safety devices are installed on equipment to protect the operator. The equipment must not be operated with such devices removed.

• Safety valves, cut-outs or other safety devices will have been set to protect the equipment. Interference with these devices may create a potential hazard.

• It is not possible to guard the operator against all contingencies. Use commons sense at all times when in the laboratory.

• Before staring a rotating machine, make sure staff are aware how to stop it in an emergency.

• Ensure that speed control devices are always set to zero before starting equipment.

FIRST AID

• If an accident does occur in the laboratory it is essential that first aid equipment is available and that the supervisor knows how to use it.

• A notice giving details of a proficient first-aider should be prominently displayed.

• A short list of the antidotes for the chemicals used in the particular laboratory should be prominently displayed.

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LABORATORY PROTOCOL

GENERAL

Each experiment presented in this manual is performed on a bi-weekly basis. The order of performance of each experiment is followed unless specified otherwise by the laboratory instructor.

Students are divided into groups of three or four to perform the experiment. Each group is required to work together throughout the semester. In other words, no switching groups in mid-stream. The same group formation in the laboratory is employed for the Micro Steam Car Design Project. Consult the Moodle site for more information.

THE STUDENT MUST ALWAYS BRING A COMPLETE AND ATTACHED COPY OF THE LAB MANUAL TO EACH EXPERIMENT. EXPERIMENT EXCERPTS, UNATTACHED OR NO LAB MANUAL DOES NOT QUALIFY AND IS SUBJECT TO PENALTY. Bring a USB flash drive to copy data files when required.

The student should always have on hand the lab manual, paper, pencil, eraser, calculator and a USB flash drive to copy data files if needed.

In order that the laboratory session is conducted in the most meaningful manner possible, it is imperative that each student read, study, and understand the experiment to be conducted prior to coming to the laboratory. The student should also read and understand the laboratory safety guidelines. Failure to follow these guidelines will result in expulsion from the laboratory.

An attendance sheet is circulated and it is the responsibility of the student to sign it at each lab session. The lab instructor is not expected to remember if the student attended and later forgot to sign the attendance sheet.

The student is required to complete all given laboratory tasks within the allotted laboratory time (110 minutes). There are no extension or makeup sessions outside the scheduled time.

At the end of each lab, the laboratory instructor must sign the completed data sheet provided in this manual. This signed sheet must be incorporated at the end of the laboratory report to be submitted by the group to receive credit.

No food or drink allowed in the laboratory. Cellular phones must be turned off during the experiment.

COMING LATE

All issues coming late to the laboratory are handled by the Laboratory Specialist.

Arriving late for whatever reason to the laboratory is deducted 20% for the experiment.

Arriving 30 minutes after the start of the scheduled lab results in a zero grade for the experiment and not allowed to enter the laboratory..

There are no makeup labs for coming late to the laboratory.

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MISSING AN EXPERIMENT

All issues missing an experiment are handled by the Laboratory Specialist.

There are no makeup experiments except for statutory holidays.

Missing an experiment for any reason results in a zero grade for the experiment unless the student provides a valid medical note (i.e. no other type of notes are accepted) to the Laboratory Specialist specifying he/she was not able to come to the laboratory on the date in question.

Once the note is verified, arrangements are made to make up the experiment with another section. The student must contribute in writing the lab report with his/her original lab group. If it is not possible to make up the experiment due to schedule conflicts, the student receives a final lab grade based only on the experiments performed during the semester. There is a maximum limit of one experiment missed with an approved note for the semester. Afterwards, it is a zero grade for each missed experiment.

LATE REGISTRATION

Registering late for the course (i.e. after the labs have started at the beginning of the semester) must attend their registered section without exception. If a student officially registers for a lab section which has completed the first experiment, the student must notify the Laboratory Specialist either by e-mail or in person. The Laboratory Specialist will make arrangements for the student to possibly attend another lab section for this one time only. The student returns to his his/her registered lab section for the next experiment.

DROPPING COURSE DURING THE SEMESTER

Out of courtesy, the student should advise his/her laboratory partners in the event of this occurrence. The student’s previous performed experiments are deleted from the record.

If a group reduces to one student then he/she is moved to another group. Two members in a group is still valid.

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LABORATORY REPORTS

GENERAL

Each group submits a complete written report covering each experiment performed. The report is to be the group’s own work. The report is written in the third person, past tense (for procedures executed, data taken, and results obtained) and should be self-sufficient. In other words, the reader should not need to consult the references in order to understand the report. Correct English and spelling should be used. The reports are practice for writing technical reports similar to those, which are required by engineers engaged in industry and engineering practice.

The reports must be typed using a word processor and stapled only (i.e. no paper clips). All pages, equations, figures, graphs and tables must be numbered. Figures, tables, graphs, etc., must have titles and be introduced in a sentence in the text of the report. Figures must have axis labels that name the variable as well as giving its symbol and units if appropriate.

Figures, graphs, and tables must be neat and clear. Figures and graphs should be generated on the computer through drawing and plotting software. Choose scales that are appropriate to the range of data and that can be easily read. Leave room on the paper for scales, labels, and titles.

SPECIFICATIONS

In order to observe the accepted rules of good writing form, the following specifications for the general makeup of the report are suggested:

• Use 8 ½ x 11 inch white paper.

• Write the report with a word processor.

• Use Times Roman or Arial fonts, Size 12 with 1.5 spacing.

• Use one side of the paper only.

• A SINGLE GRAPH SHOULD BE REPRESENTED USING THE ENTIRE SHEET OF PAPER. MULTIPLE GRAPHS ON ONE SHEET ARE NOT ACCEPTABLE.

• Graphs axes should be clearly labeled, including units where appropriate.

• Discrete experimental data that are plotted on appropriate graphs should be designated with small symbols, such as circles, to distinguish these data from those represented by curves fitted through them either intuitively or statistically or by mathematical model. If more than one dependent variable (ordinate) is presented on a graph, each variable should have a different symbol.

• When mathematically fitting curves to experimental data, use appropriate judgment. Just because a 6th order polynomial can fit exactly to 7 points does not mean that it is the appropriate curve for this experimental data (i.e. the distribution may actually be linear or quadratic). Instead look at the trend of the data and avoid the pitfall of many students in letting the computer chose the best curve fit. As a general rule, the lower the complexity of the curve fit that represents the data trends, the better.

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FORMAT

The following report outline is required for content and order of presentation:

• TITLE PAGE: Must include Lab TI-Xtle, date performed, student names with corresponding identification numbers and lab section.

• OBJECTIVE: State the objective(s) clearly in a concise manner in your own words.

• INTRODUCTION: Background information preparing the reader as to what is done during the experiment. Do not copy what is written in the manual. Any theory mentioned or relevant information must be referenced.

• PROCEDURE: A general description of the procedure should be given. This description should be comprehensive, but brief. It should include a generic list of equipment used and a sketch to show how the equipment items are related. The enumeration and detailed description of multitudinous mechanical operations or sequence of such operations such as closing switches, reading instruments, turning knobs and so forth, should in general be avoided. However, when a specific method of mechanical operation or sequence of such operations is necessary in order to insure the validity or accuracy of the test data, it is important that the essential details be included in the description. Note that it is unacceptable to simply use or copy the procedural instructions from the manual.

• RESULTS: Answer all the questions posed in the laboratory manual. All observed and calculated data should be tabulated when possible. Headings and subheadings (titles) identifying items of data or sets of data should be used.

• SAMPLE CALCULATIONS: Show a sample of a complete calculation of each type involved in the determination of calculated data and the solution of problems. These sample calculations should be first shown in symbolic form with all symbols properly defined. Then numerical data should be used with units shown in the actual calculations.

• GRAPHS: See Specifications section.

• DISCUSSION: MOST IMPORTANT SECTION OF THE ENTIRE REPORT. IT SHOULD BE A COMPLETE DISCUSSION OF THE RESULTS OBTAINED. Part of this discussion should deal with the accuracy or reliability of the results. It is suggested that this section consist, when applicable, of a careful treatment of the effect upon the results of the following:

• Comparison of the results obtained with those that would reasonably have been expected from a consideration of the theory involved in the problem. Whenever the theory is apparently contradicted, the probable reasons should be discussed.

• Errors resulting from the necessity of neglecting certain factors because of physical limitations in the performance of the test.

• When results are given in graphical form as curves, the shape of each curve should be carefully explained. Such an explanation should state the causes or the particular shape the curve may have. It is not sufficient simply to state that a particular curve has positive slope, the reason for such a slope should be given. If the slope is not constant, that is, if the curve is not a straight line, its nonlinearity should also be explained.

• Any original conclusions drawn as a consequence of the laboratory procedure and a study of the results obtained should be given in this section and should be justified by the discussion.

• Constructive criticism of any phase of the experiment that may seem pertinent may also be included here.

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• CONCLUSIONS: In this section the conclusions which were supported and drawn in the Discussion are succinctly restated, usually as a numbered list. No new information should appear in this section. All justification of conclusions should have occurred in prior sections.

• REFERENCES: Whenever referring to published sources of this kind, for example when quoting technical specifications or specialist theory, full particulars of the source in a numbered list of references must be included. Below are several examples that show the correct format for journals, books and web sites.

• Journal: [1] Hamilton, R. J., & Bowers, B. , The Kinetic Theory of Molecular Gases: A Roy Model Exemplar. Physical Science Quarterly, 20, 2007, pp 254-264.

• Book: [2] Hyde, J. S. & Delamater, J., Introduction to Physics, (10th edition) New York: McGraw-Hill, 2008, pp 220-227.

• Website: [3] cms.mit.edu/research/index.php (Accessed October 2009).

Note: Every item in the reference list must be referred to by inserting its number in the appropriate section of text. This is done using square brackets.

• APPENDICES: Materials that support the report but are not essential to the reader’s understanding of it are included here. The laboratory data sheet should be an appendix.

ORIGINALITY FORM

This form must be completed by each student and submitted to the lab instructor separately with the first lab report one time only. Failure to submit this form results in a zero grade for the experiment. A copy of the form can be found at the end of this manual. For more information, go to encs.concordia.ca/ current-students/forms-and-procedures/expectation-of-originality.

PLAGIARISM

The student is responsible for their own work and is expected to write their own thoughts. Plagiarism is a serious problem. If caught plagiarizing, the student forfeits the right to attend the laboratory, receive a failing lab grade and be removed from the university by due process as stated in the student handbook.

Plagiarism is any portrayal of information as your own when not truly yours. Plagiarism is rewriting another student’s report. Plagiarism is turning in the same report from a previous year even if a few words are moved around. Plagiarism is forgetting to cite information that was obtained outside your brain. Plagiarism is cheating.

Avoid plagiarism by signing the “Originality Form” and submitting it to the lab instructor as a separate attachment with the first lab report one time only. The signed form claims this is the product of your own work, that the material presented has been created by the student and properly cited and that no other person created or prepared the lab report.

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SUBMISSION

Each group must submit their lab report to the laboratory instructor at the following laboratory session (i.e. exactly 2 weeks from the performance date of the experiment). The final lab report for the semester is to be submitted to the Laboratory Specialist. If a lab report deadline falls on a statutory holiday, the report is to be submitted to the Laboratory Specialist the following day.

Electronic submissions by e-mail (i.e soft copies) are considered invalid. The lab instructor or Laboratory Specialist immediately disregards these type of submissions and have no weight. Hard copies of lab reports are the only form accepted.

Submission of a lab report outside the scheduled laboratory period is not accepted under any circumstances resulting in a zero grade for the experiment.

The corrected report is returned to the group in the next experiment for viewing only. The lab instructor keeps the lab report.

GRADING

The grading breakdown for each lab report out of 100 marks is as follows:

• Presentation (20%)• Results (40%)• Discussion/Conclusion (40%)

EXPERIMENT

1STIRLING ENGINE

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INTRODUCTIONWhen air is heated it expands, and when it is cooled it contracts. Stirling engines work by cyclically heating and cooling air inside a leak tight container and using the pressure changes to drive a piston. The heating and cooling process works like this: One part of the engine is kept hot while another part is kept cold. A mechanism then moves the air back and forth between the hot side and the cold side. When the air is moved to the hot side, it expands and pushes up on the piston, and when the air is moved back to the cold side, it contracts and pulls down on the piston.

OPERATION

While Stirling engines are conceptually quite simple, understanding how any particular engine design works is often quite difficult because there are hundreds of different mechanical configurations that can achieve the Stirling cycle. A typical Stirling engine is a displacement-type engine that uses two separate pistons, connected to a common flywheel (see Figure 1.1). One piston is the working or working piston; it fits snugly into the cylinder and maintains the seals on the working air. The other, a displacement piston, is moving freely inside its cylinder, shifting the working air through the gap between the piston and the cylinder from the hot tot the cold end of the cylinder and back again

Figure 1.1: Typical Stirling Engine modeled in Solidworks

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The ideal Stirling cycle can be divided into four parts (see Figure 1.2):

I. Expansion - Gas is shifted to the hot end by the displacement piston; it expands as it heats up, and pushes the working piston which in turn rotates the flywheel;

II. Cooling - Displacement piston moves, shifting the gas toward the cold end; heat is lost from the gas;

III. Compression - Cooled gas is re-compressed by the inertia of the flywheel pushing the working piston.

IV. Heating - Gas is compressed by the working piston, the displacement piston shifts it to the hot end, where the heat is absorbed into the gas.

Figure 1.2: PV diagram of the Stirling cycle (a) Ideal (b) Real

As we follow along the curve made by the measured pairs of pressure and volume, the area on the PV diagram inside the cyclical trajectory of the working cycle of the engine represents the amount of mechanical work performed by it. The work is being done by the gas on the flywheel along the upper curve and by the flywheel on the gas along the lower curve; the difference is the net work done by the engine.

Four snapshots from I to IV show the relative positions of the displacement and working pistons illustrated schematically in Figure 1.3. Figure 1.4 shows a more realistic plot of the positions of the two pistons during continuous rotation of the flywheel. Both pistons are attached to the same flywheel but at 90° to each other. As a consequence, the solid and dashed lines are a quarter of a cycle out of phase with each other. The grey region in Part II shows the part of the cycle where the working piston is near its lowest point and the gas volume is approximately at its maximum. The area above the dashed line represents the fraction of the total volume that is above the displacement piston, in thermal contact with the hot end of the cylinder. Since it takes less work to compress the gas when it is cold (against lower gas pressure) than the work done by the gas on the piston when it is hot (gas exerting higher pressure over the same piston travel distance), there is a net conversion of heat into mechanical work.

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Figure 1.3: Relative position of the displacement and working pistons for one cycle

Figure 1.4: Realistic representation of the Stirling cycle.

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EQUIPMENT

The Stirling engine can be used for qualitative and quantitative investigations of the Stirling cycle. It can operated in two different modes:

1) Heat Engine

2) Heat Pump

Typically, the Stirling engine is used as a heat engine; heat is applied to the round end of the glass tube containing the displacer piston and the engine uses some of this heat energy to perform mechanical work. If the engine is connected to a motor/generator unit, some of this mechanical energy is converted to electric energy. As a heat engine, the Stirling engine will always turn in the same direction.

If one uses an external motor to drive the Stirling engine through its thermal cycle, the net effect is the reverse conversion from mechanical energy into thermal one, heating up one end and cooling down the other end of the cylinder. If the Stirling engine is used as a heat pump, the opposite of a heat engine, a DC voltage is applied to the motor that rotates the flywheel and moves the pistons. The electrical energy is expended to transfer heat and thus create a temperature difference between the two ends of the cylinder. The direction of the transfer of heat depends on the direction of rotation. Thus the engine can heat as well as cool the round end of the glass tube relative to the other end that has a large metal heat reservoir attached to it exchanging heat with the surrounding air.

STIRLING ENGINE

The displacement cylinder and piston are made of heat resistant glass. It is also equipped with two recessed temperature measurement sockets to accept sheathed thermocouples to measure the temperature of the hot and cold. The working cylinder, flywheel and gearbox cover are made of acrylic glass. This allows for very clear observation of the individual sequences of motion at all times. The flywheel has markings to allow measurement of the RPMs using a light barrier. The crankshafts are equipped with ball bearings and made of hardened steel. The connecting rods consist of wear-resistant plastic.

TECHNICAL DATA

• No Load Speed: 1000 RPM (minimum)

• Maximum Power: 1.5 W

• Resolution: 1.5 x 10-3 N-m

• Flywheel Diameter: 140 mm (Base Plate); 70 mm (Solar)

• Working Piston Diameter: 25 mm

• Displacer Diameter: 30 mm

• Maximum Volume: 44 cm3

• Minimum Volume: 32 cm3

• Minimum Temperature Difference: 100°C

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Figure 1.6: Stirling Engine Assembly Drawings

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HEAT SOURCES

A Stirling engine is a heat engine that is vastly different from the internal combustion engine in a car or a steam engine. It uses air as working fluid and is powered by an external heat source. Thus the engine has the potential to use any heat source as a fuel like biomass, waste heat or solar energy. As the limitation of our fossil energy resources became obvious, scientists and engineers recalled the old Stirling principle to use alternative energy sources. In this experiment two different heat sources with different configurations are to be used:

1. Base Plate with an alcohol burner as the heat source to drive a Stirling engine.

2. Solar mirrors with a heat lamp used as the heat source with an attached Stirling engine.

BASE PLATE CONFIGURATION

The Stirling engine is placed on an acrylic base plate and firmly screwed from the bottom with two knurled screws as shown in Figure 1.7. Two other knurled screws on top of the base plate are used to attach the GT03 motor/generator unit or the torque meter scale. The heat source is an alcohol (or methyl hydrate burner (density = 0.83 g/ml; heating value = 25 kJ/g).

Figure 1.7: Base Plate Stirling Engine

The flywheel normally remains fastened with the aid of an Allen key. After the flywheel has been remounted, the shaft should be pulled slightly outwards and only a small air gap (i.e. the thickness of a sheet of paper) should be present between the flywheel and the motor housing so that the shaft does not have too much play when in operation.

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GT03 MOTOR/GENERATOR UNIT

The GT03 motor/generator unit has two pulleys of different size with which the influence of the transmission ratio on the power and speed of the Stirling engine can be demonstrated. A belt links the flywheel to the motor. The operating mode is selected by a switch to either generator or motor mode. In generator mode the integrated lamp lights. Two output sockets are wired in parallel to the lamp socket, enabling a variable resistance to be connected. For operation as a motor, a DC voltage from a power supply is applied to the input sockets. Maximum voltage is 12 Volts DC.

TORQUE METER

The inner metal part of the pointer (Prony brake with inclination weight) is fastened to the shaft of the Stirling motor in front of the flywheel using the Allen key. The friction between the metal part and the pointer can be changed with the adjustment screw on the pointer. When the Stirling motor runs, the pointer is carefully pushed onto the shaft. The friction should then be slowly increased; it should not be so high that motor comes to rest. The set torque is indicated on the scale. See Figure 1.8.

Figure 1.8: Torque Meter

The measurement range of the torque meter is 25 x 10-3 N-m with a resolution of 1 x 10-3 N-m. The balancing weight is 50 g.

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SOLAR CONFIGURATION

The solar powered Stirling engine uses a parabolic dish to focus the sun’s heat onto a receiver. A Stirling engine is placed near the focal point of a large parabolic dish. The dish is pointed directly at the sun using a tracking mechanism. This allows the sun’s energy to be continuously focused onto a receiver placed at the focal point. This receiver channels the heat energy into a Stirling engine which powers a generator, generating electricity.

The solar power Stirling engine setup used in the experiment does not use the sun. The sun is “mimicked” using an inside frosted crown silver incandescent type light bulb (150 Watts) attached to the base of an aluminum transmitting parabolic mirror (i.e. transmitting mirror). By positioning the bulb at the focus of the transmitting mirror, a narrow beam of light is created with high efficiency. When using ordinary clear incandescent lamps in this application, more than half of the light is radiated out of the bulb crown without striking the reflector. However with the crown silver coating, the forward rays are reflected back to the transmitting mirror and collimated into its beam with high efficiency. On top of this, the bulb coating completely masks the filament from view and presents a very low glare form of spotlight. When properly aimed at the receiving parabolic mirror (i.e. receiving mirror); it focuses the incoming light rays on the hot side of the Stirling engine (i.e. same one used in base plate configuration with a smaller diameter flywheel). An aluminum rack with angle supports of different height is used to mount the mirrors. The transmitting mirror is positioned about three times higher than the receiving mirror. Each parabolic mirror has the same diameter (470 mm) and positioned about 1 meter apart. Figure 1.9 illustrates the solar set indoor setup.

Figure 1.9: Solar Set Indoor Stirling Engine

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The Stirling engine is attached to the base of the receiving parabolic mirror. The end of the displacer glass tube (i.e. hot side) is encapsulated with a black absorbent ring which glows while in operation as shown in Figure 1.10.

Figure 1.10: Stirling engine attached to base of a parabolic aluminum mirror

The engine is driving a generator/motor unit with fixed resistance load of 1 kΩ.

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THEORYAccording to first law of thermodynamics, when thermal energy is supplied to an isolated system, its amount is equal to the sum of the internal energy increase of the system and the mechanical work supplied by the latter:

(1.1)

It is important for the Stirling engine that the thermal energy produced during the cooling phase be stored until it can be used again during the heating phase (regeneration principle). Thus during the heating phase, the amount of thermal energy released is absorbed during cooling. In other words, only an exchange of thermal energy takes place within the engine. Mechanical work is merely supplied during expansion and compression. The internal energy remains unchanged during an isothermal process thus work performed during is equal to the absorbed energy (expansion) and released energy (compression).

For an ideal gas:

(1.2)

where P is the pressure, V is the volume, T is the temperature and n is the number of moles contained in the system. R is the universal gas constant.

The amount of work produced during expansion is:

(1.3)

It is negative because this amount of work is supplied.

Consequently, the amount of work exerted during compression is:

(1.4)

|W1| > W3 because T1 > T2.

The net work Wnet is equal to the area of the PV diagram or the sum of W1 and W3 or:

(1.5)

Only part of the net work can be used as effective mechanical work Wm through exterior loads applied to the engine. The rest contains losses within the Stirling engine.

Effective mechanical energy during a cycle is calculated using the torque M displayed by the torque meter:

(1.6)

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The rotational speed of the flywheel is converted to frequency (f) which allows the calculation of the mechanical power Pm:

(1.7)

Effective electrical power (Pe) is calculated by measuring the voltage (U) and current (I) at the load resistor:

(1.8)

The maximum thermal efficiency of a reversible process within a heat engine is equal to the ratio between net work and the amount of supplied heat Q1 = -W1 or

(1.9)

Carnot found this to be the maximum thermal efficiency for any heat engine which can only be reached theoretically. The efficiency increases with increasing temperature differences.

REFERENCES

1. Instruction Manual, Stirling Motor GT03 and Solar Set Indoor, Stirling Shop, Germany.

2. C.G. Deacon, R. Goulding, C. Hardiass, B. deYoung, Demonstration Experiments with a Stirling Engine, Phys. Educ., vol. 29, 1994, pp 180-183.

3. www.3bscientific.de/product-manual/1002594_EN.pdf (Accessed July 2017).

4. www.leybold-shop.com/physics/physics-equipment/heat/heat-and-work/thermal-machines/hot-air-engine-p-388176.html (Accessed July 2017).

5. youtu.be/tNtEZ_UNtwg (Accessed July 2017).

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EXERCISE A : MEASURING MECHANICAL POWER (SETUP #1)

PROCEDURE

1. Weigh initial weight of the alcohol burner using the provided digital scale.

2. Light the burner and start the timer.

3. After a minute, turn the flywheel to start the Stirling engine.

4. When thermal equilibrium is reached (approximately 5 minutes), record the two temperatures from the temperature display unit and rotational speed using the tachometer pointed on the flywheel mark. All data is recorded on the data sheet found at the end of this lab manual.

5. Fix the pointer on the flywheel axis.

6. Apply a torque of about 2.5 x 10-3 N-m using the torque meter by adjusting the screw on the pointer carefully for it not to oscillate.

7. Record the temperatures and rotational speed.

8. Repeat for increasing torque at intervals of approximately 2.5 x 10-3 N-m up to 15 x 10-3 N-m or when the engine stops.

9. Turn off the alcohol burner by placing the cover over the open flame.

10. Record the time elapsed and the final weight of the alcohol burner.

RESULTS

1. Calculate the Stirling engine, mechanical and frictional power for each torque setting. Assume a value of n = 1.1 x 10-3 moles. Show sample calculations and tabulate all your results.

2. Plot a graph of torque as a function of rotational frequency. Where is the torque maximum? What are the highest and lowest values?

3. Plot a graph of mechanical power as function of rotational frequency. What is the effective power or work for this engine?

4. Calculate the total efficiency of the engine and thermal efficiency of the alcohol burner.

5. What is the mechanical and Carnot efficiency of the Stirling engine?

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EXERCISE B: MEASURING ELECTRIC POWER (SETUP #2)

PROCEDURE

1. Light the alcohol burner and after one minute, turn the flywheel to start the Stirling engine.

2. When thermal equilibrium is reached (approximately 5 minutes), record the two temperatures and rotational speed WITHOUT the transmitting belt.

3. Place the belt to the large strap wheel on the generator/motor unit carefully. DO NOT BURN YOURSELF! Record the temperatures, rotational speed, output voltage and current of the generator/motor unit on the data sheet WITHOUT LOAD (Toggle switch is in the off position).

4. Turn the switch on and the potentiometer connected to the load resistor about one turn (variable resistance) and record the temperatures, rotational speed, output voltage and current of the generator/motor unit on the data sheet.

5. Repeat by further turning the potentiometer about one turn in the same direction and record the data up to 10 turns.

6. Return the potentiometer back to its original setting.

7. Place the belt to the small strap wheel carefully and repeat the above steps. DO NOT BURN YOURSELF!

8. Turn off the alcohol burner by placing the cover over the open flame. Turn toggle switch off.

RESULTS

1. Calculate the power output of the generator/motor unit for different applied loads (i.e. at the different potentiometer settings). Show your sample calculations and tabulate all your results. Make two tables for the belt configuration.

2. Plot the electric power versus rotational frequency. On the same graph, plot both curves for each belt configuration. What is the effective electrical power?

3. Calculate the torque corresponding to the different output powers and plot the torque as a function of rotational frequency.

4. Describe any differences associated with the belt configuration.

5. Compare the results obtained with the electric generator and those obtained with the torque meter.

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EXERCISE C: SOLAR STIRLING ENGINE (SETUP #3)

PROCEDURE

1. The solar Stirling engine is already running due to time constraints.

2. Record the temperatures, rotational speed and output current and voltage without the belt, with the belt on the small strap wheel and the toggle switch off and then on.

3. Place the “black cloud” onto the receiving mirror and start the timer.

4. Using a stopwatch, record all the data at about one minute intervals until the engine reaches thermal equilibrium.

5. Place a larger “black cloud” onto the receiving mirror and repeat the above steps.

6. Shut off the power to the heat lamp.

RESULTS

1. Calculate the Stirling engine power as the heat input decreases.

2. How does the larger “black cloud” affect the engine power? Explain your answer.

3. What do your results mean for the use of solar power in Canada? Research any required data to support your answer. (Hint: you might at some point want to look up historical cloud coverage data.)

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EXERCISE D: STIRLING ENGINE AS A HEAT PUMP (SETUP #4)

PROCEDURE

1. Rotate manually the engine slowly by turning the flywheel clockwise and then counterclockwise. Note the relative movement of the working piston to the displacement piston. The two pistons are offset by 90°.

2. Connect the two wires between the motor/generator unit and the power supply. Red to red and black to black. The voltage that is applied to the motor is adjusted by turning a knob and monitored on the corresponding digital display in Volts (U). The current flowing through the motor is shown on the other meter in Amperes (I).

3. Check the toggle switch is on.

4. Turn on the power supply and increase the voltage to 10 Volts. The engine should start to rotate.

5. Carefully touch the glass cylinder to see if it is hot or cold. Note the direction of the flywheel and the temperatures.

6. Turn off the power supply and switch the two wires (red to black and black to red).

7. Turn the power supply back on and set the voltage to 10 Volts. The heat pump should rotate in the opposite direction.

8. Carefully touch the glass cylinder to see if it is hot or cold.

RESULTS

1. Explain why is the cylinder hot in one direction and cold in the other direction? Your answer should be an engineer’s response.

2. How is it possible for the Stirling engine to reach high rotational speeds if the temperature difference in the glass cylinder is so small?

3. What is the direction of the flywheel when in heat and cool modes? To which side is the heat being pumped?

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DATA SHEETEXPERIMENT 1: STIRLING ENGINE

EXERCISE A : MEASURING MECHNICAL POWER (SETUP #1)

Initial Burner Weight [g]: _________________

Final Burner Weight [g]: _________________

M [x 103 N-m] Speed [RPM] T1 [°C] T2 [°C]

02.55.07.510.012.515.0

Elapsed Time [s]: _________________

EXERCISE B: MEASURING ELECTRICAL POWER (SETUP #2)

Large Strap Wheel

Speed [RPM] T1 [°C] T2 [°C] U [V] I [mA]Without BeltWithout Load

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Small Strap Wheel

Speed [RPM] T1 [°C] T2 [°C] U [V] I [mA]Without BeltWithout Load

EXERCISE C: SOLAR STIRLING ENGINE (SETUP #3)

“Small Cloud”

Time [min] Speed [RPM] T1 [°C] T2 [°C] U [V] I [mA]0 Without Belt0 Without Load012345678910

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“Big Cloud”

Time [min] Speed [RPM] T1 [°C] T2 [°C] U [V] I [mA]0 Without Belt0 Without Load012345678910

EXERCISE D: STIRLING ENGINE AS A HEAT PUMP (SETUP #4)

Notes

EXPERIMENT

2 CYCLEPAD

1718

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INTRODUCTION

CyclePad is the first open source simulation software allowing the simulation of complex thermodynamic cycles. It is user-friendly and allows the determination of the characteristics of several simple to complex cycles (net work, heat input, thermal efficiency, Carnot efficiency etc…).

GETTING STARTED

We would like to outline the steps involved in setting up a typical Rankine cycle, which is a very common ideal steam power cycle (see Figure 2.1). Using CyclePad, setting up such a cycle is actually very simple, but it requires that we know some of the basic facts and typical assumptions that apply to the cycle. We will examine a typical Rankine cycle problem and note the assumptions necessary to find the problem’s solution, many of which will not be stated explicitly in the problem.

Figure 2.1: Ideal Rankine Cycle Using Cyclepad

TYPICAL PROBLEM

Let’s say we want to set up a typical Rankine Cycle. A typical problem statement is:

Consider an ideal steam cycle in which steam enters the turbine at 5 MPa, 400ºC, and exits at 10 kPa. Calculate the thermal efficiency and the net work per kilogram of steam.

This may not sound like a very complete problem description, since we are given only three numbers. However, it is sufficiently described that we can solve it. Here we will detail the other properties of a Rankine cycle which allow us to complete its design.

WHAT IT LOOKS LIKE

First, an “ideal steam cycle” where we are only told of one turbine is probably a Rankine cycle. This cycle consists of a heater, a turbine, a cooler (or “condenser”), and a pump, in that order. We will talk about the properties of each component and the state points between them later. Right now we have enough to set up the cycle’s basic layout.

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ANALYZING OUR DESIGN

With the design layout complete, we turn to adding the assumptions which allow CyclePad to solve the cycle. For this example, we will go around the design and add what information we know as we go, clicking on each device or state point to get its meter window to show up. It is particularly during this stage that our own knowledge of thermodynamics is critical to making assumptions CyclePad will use in design solution. We start at the heater.

THE HEATER (HTR1)

We aren’t explicitly told anything about the heater, but we know that a Rankine cycle has ideal components. Heaters are usually a long series of tubes through which the working fluid is forced. As it moves through the tubes, heat (from a combustion process, for instance) is applied to the outside of the tubes and the working fluid gains enthalpy. In real heaters, it takes energy to push the fluid through all of these tubes and there is a pressure loss for the process. In an ideal heater, we assume that this pressure loss is negligible and the heater is isobaric.

(When we consider non-ideal components, we are often given a pressure loss (or a relation that allows us to compute a pressure loss) for the heater. In that case, we could enter the pressure loss as delta-P for the heater.)

We also notice that we might assume the heater to be isochoric (no change in specific volume or density). Since we will have liquid water entering the heater but steam (which is far less dense) leaving it, we know this is not the likely assumption for an ideal heater.

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THE TURBINE INLET (S2)

Looking now at the state point after the heater, we know both the pressure and temperature of the fluid at this state point from the problem statement. In addition, we are dealing with a steam cycle, so our working fluid is made of water.

We are also given the temperature and pressure at this state point. Entering their values, this state point’s intensive values are completely determined.

When T and P have been entered, CyclePad pauses for a second and figures out the other intensive properties at this state point, like specific volume, specific internal energy, etc (see Figure 2.2). If we were doing this problem by hand, these are all values we would have to look up in tables.

Figure 2.2: Turbine Inlet (S2) properties

THE TURBINE (TUR1)

The next component is the turbine. While we aren’t told anything explicitly about this turbine, it is ideal. In general, this means it is isentropic (zero change in entropy) and adiabatic (no heat transfer). Even if we did not know that it was ideal, we would probably assume it to be adiabatic because we have not been told how much heat transfer takes place and we have no way to figure it out.

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THE TURBINE OUTLET (S3)

At the outlet of the turbine, we notice that the specific entropy is already known. (It is the same as that for the state point before the turbine because the turbine is isentropic.) We are told in the problem that steam exits at 10 kPa, so we assume the pressure at this state point to have that value. Since we now know both the pressure and the entropy at this state point, we know all of the intensive property values here. (Once again, CyclePad has saved us much time in table lookup, especially since this state point would require interpolation to find.)

OTHER TURBINE OUTLET ASSUMPTIONS

We are told the turbine outlet pressure in this problem, and that is the most common case, but there are other possibilities as well. We might instead know:

• The turbine pressure ratio (PR). In this case, there would be nothing to enter at S3, and we would assume a value for PR in the turbine’s meter window.

• The turbine outlet quality. Turbines can typically only handle fluid down to a certain quality; lower qualities can damage them. But we want the quality to be as low as the turbine can handle in order to extract the most energy from the working fluid. In such cases, we often assume a quality at the turbine outlet and let the state be determined by that and the outlet entropy.

Note that the turbine outlet quality of 80% is dangerously low for practical use. We might wish to address this problem by adding a reheat stage.

THE COOLER (CLR1)

Similar to an ideal heater (and for the same reasons), an ideal cooler has no pressure drop, so we make the isobaric assumption here as we did with HTR1.

THE PUMP INLET (S4)

This is a state point when our own knowledge and reasoning about cycles is key to making assumptions. The only reason we have a cooler before the pump at all is because we know pumps can be damaged by non-liquids. To avoid this, the cooler must condense all of the steam leaving the turbine into a liquid before we send it to the pump. So we at least want to cool our saturated working fluid to 0% quality before sending it to the pump. Figure 2.3 shows the region to which we must cool the working fluid before safely using a pump.

Figure 2.3: T-s diagram for water

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Of course, pumps can work with compressed liquids as well, so we could cool the fluid even past saturated fluid down into the compressed liquid region. We do not do this for several reasons related to cycle efficiency.

For CyclePad, we can specify that a fluid be saturated by selecting a phase and choosing it to be saturated. Once we have told CyclePad that the phase is saturated, it adds another property to the meter window, allowing us to specify a quality. In this case, we want to assume that quality is zero, since we are forcing the fluid at S4 to be a saturated liquid.

OTHER PUMP INLET ASSUMPTIONS

Sometimes we can’t cool the working fluid just until it is a saturated liquid. Most often this is because our cooling source is at a specified temperature and we cannot remove the working fluid from the cooler early enough. In these cases, we are usually given a temperature for this state.

THE PUMP (PMP1)

We are given no explicit information about the pump, but, like the turbines, ideal pumps are adiabatic and isentropic. We assume both of those things here. Note, CyclePad uses the equation wpump = -vΔP to calculate reversible pump work because the fluid (liquid water) is very close to incompressible. Sometimes CyclePad finds a small heat transfer for the pump and, because this heat transfer isn’t quite zero, CyclePad asserts that the pump is not adiabatic or causes a contradiction when we assert that the pump is adiabatic.

Why does this happen? The reason lays in the approximation that the water in the pump is incompressible, which is very close to accurate, but the slight variation in v between the saturated liquid at the inlet and the compressed liquid at the outlet causes this small heat transfer to show up, confusing CyclePad. This is more likely at low pump inlet pressures (under one atmosphere) than at higher ones.

For our purposes, this heat transfer is not important (it is typically on the order of 0.1% of the work done by the pump), so we can just not worry about whether the pump is adiabatic if some heat transfer has already been found or the adiabatic assumption causes a contradiction.

In general, we might try to change the order in which we make assumptions, just to be certain no contradictions occur later on. We could, for instance, always choose adiabatic before isentropic, or make the pump assumptions before those for the pump inlet. In these instances CyclePad will note the small heat transfer and assume that it is due to round-off accumulation.

THE PUMP OUTLET (S1)

Typically, this state is already known because we know the pressure (the same as for the turbine inlet for an isobaric heater) and the entropy (the same as for the pump inlet for an isentropic pump). In cases where this state is not known, it is because we have a non-ideal component in our system (such as a non-isobaric heater). In those cases the problem statement will typically include information about the pump outlet pressure or the pump’s pressure ratio.

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FINISHING THE PROBLEM

Our original problem was to find the thermal efficiency of this cycle. Go to the “Cycle” menu and choose “Cycle Properties”. This meter window is mostly empty because CyclePad doesn’t know which definitions for efficiencies to use and they are different for a heat engine (like our Rankine cycle) than they would be for a refrigeration cycle, for instance. Here we need to tell CyclePad that we are modeling a heat engine. We see that the Carnot efficiency is just over 52.6% (see Figure 2.4).

However, we notice that CyclePad still does not know the many of the values in this cycle. Among the unknown values is the net work per kg of steam and the thermal efficiency, which we are asked to find in the problem statement. The reason is that CyclePad finds some whole cycle properties based on extensive values, which are not known until we assume a mass flow rate (mdot). (In other words, CyclePad needs the whole heat transfer Q, not the specific heat transfer q).

Figure 2.4: Cycle Properties

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PROBLEMS

Solve the following problems using CyclePad:

1. Consider an ideal Rankine cycle in which steam enters the turbine at pressure of 3 MPa and a temperature of 450°C. The pressure within the condenser is 50 kPa.

a. Compute the actual Carnot and thermal efficiencies.

b. Plot the T-s diagram for the actual Rankine cycle.

c. Plot and comment the variations in (i) Carnot and thermal efficiencies (ii) steam quality at turbine outlet; for inlet turbine temperatures of [450 500 550 600] °C.

d. Plot and comment the variations in (i) Carnot and thermal efficiencies (ii) steam quality at turbine outlet; for condenser pressures of [50 40 30 20 10] kPa.

2. Consider now an ideal regeneration Rankine cycle working under the same conditions as above.

a. Represent using CyclePad the ideal regenerative Rankine cycle.

b. Plot and comment the variations in thermal efficiency for feed water pressures of [200 400 600 800 1000] kPa.

REFERENCES

• www.qrg.northwestern.edu/projects/NSF/cyclepad/cyclepad.htm (Accessed November 2009).

EXPERIMENT

3 REFRIGERATION

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EXERCISE A : BUILD A LOW COST AIR CONDITIONER

INTRODUCTION

We owe a lot to the humble air conditioner. Like most inventions, the idea came from a very real need: relief from extreme temperatures. The quest for cooler air has a venerable history. In ancient Egypt, people hung reeds in windows after dipping them in water; the water evaporated, cooling the air that blew through the window. Over time, innovators in China, England, and the United States transformed this cool idea into our familiar household staple. But for all their virtues, modern in-window air conditioners are not perfect machines. For one thing, they cost a small fortune to run. But with a fan, you can get all the benefits of a window AC for far less than a store-bought unit by using that same age-old concept: ice.

In this lab, you will assemble a do-it-yourself low cost air conditioner using ice.

“The units are clearly not large enough to replace your air conditioner, but they work well enough to cool small rooms. They look complicated, but it’s very basic work that involves a fan, a large container like an ice chest or bucket, and some ice. It might not look great, but you know what it feels great, especially in the summer time. And this thing is much cheaper to run than standard A/C.” - KFSN News.

MATERIALS

• Plastic container (750 ml) with lid

• Large plastic glass (295 ml)

• Small plastic glass (50 ml)

• Glue gun

• Glue sticks

• 7 X 20 mm DC motor (0.4 Watts @ 3.7 Volts)

• 55 mm diameter fan

• Plastic bushing

• AA Battery (1.5 Volts)

• 30 mm (approx.) thin gauge wire

• Marker

• Scissors

• Ruler

• 6 to 8 Ice cubes

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PROCEDURE

1. Trace a hole using a marker on the side of the plastic container. The lipped end of the small plastic glass is your guide.

2. Cut the trace with the scissors.

3. Cut the base of the small plastic glass.

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4. Trace the large plastic glass about 50 mm from the lipped end.

5. Cut the trace around the large plastic glass.

6. Insert firmly the plastic bushing onto the DC motor.

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7. Place motor/bushing assembly into the pre-drilled large center hole of the lid. The shaft should be located on the inside of the lid. In addition, the lid has numerous predrilled smaller holes (snowflake configuration) to allow for air flow.

8. Attach the fan to the end of the motor shaft.

9. Take the gun and apply glue around the assembly to stick onto the inside center of the lid.

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10. Glue the cut large plastic glass to the inside center of the lid.

11. Glue the lipped end of the small plastic glass to the cut hole of the plastic container.

12. Glue the AA battery onto the exterior side of the plastic container. The battery has wires pre-soldered to each terminal.

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13. Put ice cubes about half full in the large plastic container.

14. Close the plastic container with the lid and manually wrap the wires in REVERSE. The fan turns on and runs in the opposite direction for improved air flow.

15. Observe the temperature of the air flow coming out the vent. The room temperature was 21.5°C.

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DISCUSSION

• Describe in thermodynamic terms how does this do-it-yourself air conditioner work?

• How would you go about in improving this air conditioner in terms of energy consumption and efficiency? Give at least 3 examples.

Include your responses in a separate Discussion when submitting the lab report.

REFERENCES

1. http://www.instructables.com/id/Simple-Cheap-Ice-Box-Air-Conditioner/ (Accessed October 2016)

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EXECRISE B: ROOM AIR CONDITIONER ANALYSIS

INTRODUCTION

The room air conditioner is the simplest type of packaged air conditioner which can be installed through a wall or window. Filtering, cooling and air distribution are combined in a compact package. The room air conditioner consists of a case, which is divided into two sections (outdoor and indoor) by a partition as shown in Figure 3.1 The outdoor section consists of a hermetically sealed motor driven compressor, condenser and motor driven fan. The compressor and motor are housed in the bottom part and condenser and fan with small motor to run the fan are housed in the top part. The indoor section consists of the evaporator and the motorized fan. The air filter and power connection are housed on the bottom of the unit. The air conditioner is fitted in an opening in the wall or window such that the outdoor section remains outside the wall. The indoor portion is fitted with bottom and top shutters which can be set at different inclinations.

Figure 3.1: Model of a Room Air Conditioner

When an air conditioner is working, the low-pressure vapor refrigerant is drawn from the evaporator to the compressor and it is compressed to high pressure and temperature. This high pressure and high temperature vapor is condensed passing through the condenser. The condensed liquid at high pressure is passed through the capillary tube and then flows through the evaporator. As refrigerant comes out of the capillary tube, the pressure and temperature decrease and it starts boiling absorbing the heat in the evaporator compartment from the air and is vaporized. The compressor again draws this low-pressure vapor and the cycle is repeated. The main components are identified and shown in Figure 3.2. For condensing the high pressure refrigerant vapor, the air is drawn by a fan from the bottom of the outside compartment, passed over the condenser and discharged to the atmosphere from the top. The air from the room to be cooled is drawn with the help of another fan through the air filter from the bottom and passed over the evaporator. The air loses its heat and moisture giving out its heat to the refrigerant passing through the evaporator. The cooled and dehumidified air is thrown into the room through the dampers from the top. Figure 3.3 shows a schematic of the air conditioning cycle.

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Figure 3.2: Identified components of a Room Air Conditioner

Figure 3.3: Schematic of a Room Air Conditioner

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APPARATUS

A Danby 5000 BTU window air conditioner Model DAC050MUBIGDB with the following specifications is used for the analysis:

• Cooling capacity of 5237 BTU/hr cools up to 150 square feet

• R410A refrigerant

• Mechanical controls

• 2 way air direction

• Removable air filter

• 2 fans speeds (High/Low)

• Variable temperature control from 17°C to 30°C (62°F to 86°F)

• 379 W electrical input (compressor)

• 0.6 HP horse power (compressor)

THEORY

The Second of Law of Thermodynamics includes the statement, “It is impossible to transfer heat from a region at a low temperature to another at a higher temperature without the aid of an external agency.” Heat and refrigerators are examples of machines which transfer heat from a low to a high temperature region and the “external agency” employed may be either work or high grade heat.

The First Law of Thermodynamics states that in a cycle the net heat transfer is equal to the net work transfer. Thus for a heat pump, Heat Transfer at Low Temperatures + Heat Transfer at High Temperatures = Work Transfer (applying normal sign convention). In the case of a heat pump or refrigerator using a work input (i.e. vapour compression cycle), it follows that Heat Transfer at Low Temperature + Work Input = Heat Transfer at High Temperature. If the external agency is high grade heat (i.e. absorption cycle), then Heat transfer at Low Temperature + Heat Transfers at High Temperatures = 0.

REVERSE CARNOT CYCLE

The ideal refrigerator is represented by the Reverse Carnot Cycle as illustrated in Figure 3.4 in which heat is taken in from a constant low temperature source TL and is rejected to a constant higher temperature sink at TH.

Figure 3.4: Reverse Carnot Cycle; (a) Schematic and (b) T-s diagram

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Wet vapour at point 1 is compressed isentropically from a low pressure PL to a high pressure PH. Vapour at point 2 is passed into a heat exchanger (condenser) and heat is rejected at constant pressure to a cooling medium (sink) so that the vapour condenses and becomes saturated liquid at point 3. The high pressure saturated liquid is expanded isentropically from PH to PL and the resulting very wet vapour is passed into a heat exchanger (evaporator) at point 4. In the heat exchanger, the vapour evaporates at a low temperature taking in heat from the low temperature source and reaches point 1. The cycle repeats.

CYCLE ANALYSIS

Heat transfer in the evaporator:

(3.1)

Heat transfer in the condenser:

(3.2)

Since compression and expansion processes are isentropic and there are no other heat transfers, the net heat transfer in the cycle is:

(3.3)

and from First law of Thermodynamics:

(3.4)

where Wnet is negative and represent work input.

The coefficient of performance of a heat pump (COPHP) is the ratio of Heat Delivered at a High Temperature / Work Input.

Thus, for the Reverse Carnot Cycle:

(3.5)

The coefficient of performance of a refrigerator (COPR) is the ratio of Heat Taken in at Low Temperature / Work Input.

Thus, for the Reverse Carnot Cycle:

(3.6)

Strictly according to sign convention, this is negative but for convenience it is usually written TL/(TH – TL) which is positive.

Qevp = ∫1

4 Tds = TLDs

Qcond = ∫3

2 Tds = THDs

Qnet = Qevp + Qcond

Wnet = TLDs – THDs = (TL – TH)Ds

COPHP = = = or Qcond – THDs – TH TH

Wnet (TL – TH)Ds (TL – TH) TH – TL

COPR = = or Qevp TLDs TL

Wnet (TL – TH)Ds TL – TH

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IDEAL VAPOUR COMPRESSION CYCLE

Although no refrigerator or heat pump can have a coefficient of performance higher than that of a Reverse Carnot cycle operating between the same source and sink temperatures, the Carnot cycle is unattractive. This is largely because of the practical problems associated with the design of an expander which would take in haigh pressure liquid and pass out very wet vapour at a low pressure while producing a small work output. There would also be irreversibilities in a practical attempt to make a Carnot cycle.

In the modern vapour compression cycle as illustrated in Figure 3.5, a throttling process is substituted for the isentropic expansion process 3-4 in the Carnot cycle and although the coefficient of performance suffers due to the introduction of this highly irreversible process, the reliability and simplicity gained far outweigh the small increase of work input required.

Figure 3.5: Ideal Vapour Compression Cycle; (a) Schematic and (b) T-s diagram

CYCLE ANALYSIS

Although the throttling process is considered to be adiabatic, it is in fact irreversible and entropy increase from s3 to s4 during expansion.

Heat transfer in the evaporator:

(3.7)

Heat transfer in the condenser:

(3.8)

Since process 1-2 and process 3-4 are adiabatic in the ideal cycle, the net work transfer is:

condenser:

(3.9)

Qevp = ∫1

4 Tds = TL(s1 – s4)

Qcond = ∫3

2 Tds = TH(s3 – s2)

Wnet = Qevp + Qcond = TL(s1 – s4) – TH(s3 – s2)

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The coefficient of performance for a heat pump and refrigerator are:

(3.10)

and

(3.11)

respectively. These expressions can be evaluated but it is more convenient in practice to illustrate cycles on a pressure-enthalpy diagram as shown in Figure 3.6.

Figure 3.6: P-h diagram for an ideal vapour compression cycle

For the compressor:

(3.12)

COPHP =Qcond

Wnet

COPR =Qevp

Wnet

q1 – 2 = h2 – h1 + w

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If compression is adiabatic, q1 – 2 = 0 or:

(3.13)

Note that this implies an input of work which by convention is negative.

For the condenser:

(3.14)

but at the condenser, w = 0, therefore:

(3.15)

Note that this is a rejection of heat from the system which by convention is negative.

For the expansion valve:

(3.16)

but w = 0 and the throttling process is adiabatic, q3-4 = 0, therefore:

(3.17)

For the evaporator:

(3.18)

wcomp = h1 – h2 and W.

comp = m.

r (h1 – h2)

qcond = q2 – 3 = h3 – h2 + w

qcond = h3 – h2 and Q.

cond = m.

r (h3 – h2)

q3 – 4 = h4 – h3 + w

h4 = h3

qevp = q4 – 1 = h1 – h4 + w

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but at the evaporator, w = 0, therefore:

(3.19)

Note that this is a heat input to the system which by convention is positive.

PRACTICAL VAPOUR COMPRESSION CYCLE

The practical cycle differs from the ideal cycle in the following ways:

• Due to friction, there will be a small pressure drop between the compressor discharge and expansion valve inlet, and between the expansion valve outlet and the compressor suction.

• The compression process is neither adiabatic nor reversible. There will be usually be a heat loss from the compressor and, obviously, there are frictional effects.

• The vapour leaving the evaporator is usually slightly superheated. This makes possible automatic control of the expansion valve and prevents compressor damage by ensuring no liquid enters the suction valve.

• The liquid leaving the condenser is usually slightly sub cooled (i.e. it is reduced below the saturation temperature corresponding with its pressure. This improves COP and reduces the possibility of the formation of vapour due to the pressure drop in the pipe leading to the expansion valve.

• There may be small heat inputs or losses to and from the surroundings to all parts of the circuit depending upon their temperature relative to the surroundings. The net effect of these losses or irreversibilities on the cycle diagram is shown in Figure 3.7.

Figure 3.7: P-h diagram for simple practical vapour compression cycle

qevp = h1 – h4 and Q.

evp = m.

r (h1 – h4)

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RECIPROCATING COMPRESSOR PERFORMANCE

Most heat pumps and refrigerator compressors run well above ambient temperature and there is a heat transfer from the compressor to the surroundings. In addition as the compressor is hermetically enclosed with the motor windings, electrical heating losses will be directly added to the system.

The enthalpy change, h2 – h1, is therefore the difference between the electrical input and the total heat transfer to the surroundings and should therefore not be regarded as the work input to a practical compressor.

(3.20) h2 – h1 = q1 – 2 – wcomp

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PROCEDURE

1. Record the temperature at the 4 key points indicated on the data sheet.

2. Record the two pressures from the red and blue pressure gauges (low-side and high-side) on the data sheet.

RESULTS

1. Show the key points (1, 2, 2s, 3, 4, 4’) on the given pressure-enthalpy chart on the next page. Tear the page out or photocopy and insert in your lab report. Comment on each process (i.e 1-2,1-2s, 2-3, 3-4, 3-4’ and 4-1).

2. Determine the specific enthalpies at the key points.

3. Calculate the mass flow rate of the refrigerant. Hint: Determine the heat transfer of the refrigerant in the evaporator based on the given cooling capacity data of the air conditioning unit.

4. Determine the heat transfer of refrigerant using the calculated mass flow rate in Question #3 on the following:

a) Compressor

b) Condenser

5. Perform an energy balance on the whole cycle (i.e. Net Heat Transfer = Net Work). Is there any discrepancy between these two values? If so, why?

6. Calculate the COP for this air conditioner.

REFERENCES

1. http://home.howstuffworks.com/ac.htm (Accessed October 2016).

2. http://inspectapedia.com/aircond/Air_Conditioning.php (Accessed October 2016).

3. P.A. Hilton Ltd, Experimental Operating and Maintenance Manual, Air and Water Heat Pump R831, September 1996.

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DATA SHEETEXPERIMENT 3: REFRIGERATION

EXERCISE B: ROOM AIR CONDITIONER ANALYSIS

Atmospheric Pressure [kPa]: 101

Refrigerant Reference Units Reading

R410A

Compressor Suction Gauge Pressure (P1) [psig]

Condenser Gauge Pressure (P2)

[psig]

Compressor Suction Temperature (T1) [°C]

Compressor Delivery Temperature (T2) [°C]

Condensed Liquid Temperature (T3) [°C]

Evaporator Inlet Temperature (T4)

[°C]

EXPERIMENT

4AIR CONDITIONING UNIT

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INTRODUCTION

The Armfield RA2 Unit shown in Figure 4.1 represents a model of an Air Conditioning system by demonstrating the effects of essential Air Conditioning processes: cooling, heating, humidifying and dehumidifying. The effect and relationships of the primary processes involved in air handling systems can be investigated. The RA2 Unit is designed so that the student can simulate different environments and perform measurements to allow psychrometric data analysis.

The unit is totally self-contained and is supplied with software and a computer interface device to allow remote control, on-line monitoring and logging of results.

Figure 4.1: Armfield RA2 Air Conditioning Unit

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DESCRIPTION

Where necessary, refer to Figure 4.2 and 4.3.

Figure 4.2: Front View of Apparatus

Figure 4.3: Top View of Apparatus

OVERVIEW

The RA2 is a bench-top unit which comprises of a square ventilation duct mounted on a mild steel support frame. The duct is made of clear acrylic so all components are clearly visible: air fan, air preheater, humidifier tube, chiller/dehumidifier heat exchanger and air reheater. The duct consists of 4 main parts: Left-Hand (LH) assembly, Right-Hand (RH) assembly, Fan assembly and Louvre assembly.

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An axial fan moves the air to be conditioned through the duct. Heating elements are used to heat the air. Humidification is provided by steam delivered through a tube from a boiler. The refrigerating capacity is generated by an evaporator (heat exchanger) which is connected to the refrigeration unit. The refrigeration unit and boiler are located underneath the duct.

Temperature and humidity sensors record the temperature and relative humidity at every stage of operation. The air flow rate is determined using an air velocity transmitter. An acrylic louvre is located at the end of the duct.

The equipment needs to be connected to a suitable PC to allow remote control and data acquisition with the RA2 software.

CONTROL BOX

The control box illustrated in Figure 4.4 is located beneath the louvre assembly. Accessible from the front of this are the On/Off power switch for the whole unit, the RCD switch and test button, and the USB socket for connection to a PC.

The signals accessible via the USB interface include the On/Off remote compressor switch, fan speed control, air velocity display, preheater, reheater and boiler heater control, temperature sensor displays and Relative Humidity sensor display.

Figure 4.4: RA2 electrical control panel

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AXIAL FAN

The axial fan shown in Figure 4.5 moves the air through the duct. The speed of the fan may be controlled to give different air flow rates. The fan must be on when both the pre-heater and re-heater are on to avoid heat damage to the acrylic duct during operation.

The fan is protected with a guard, which prevents objects from reaching the blades.

Figure 4.5: Front view of fan assembly

PRE-HEATER AND RE-HEATER

The pre-heater comprises two electric elements of 200 W each, for a total power of 400 W as shown in Figure 4.6. It is located downstream of the fan in order to preheat the air flowing through the evaporator. In the second part of the duct, after the evaporator, there is a re-heater (200 W) which can be used to reheat the cooled or cooled and dehumidified air. The elements are arranged at an angle to give efficient heat transfer to the air stream. Air sensing thermostats are incorporated in the duct above the heater elements to provide overheat protection.

Figure 4.6: Heating coils

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EVAPORATOR

The refrigerating capacity of approximately 500 W at 20°C is generated by an evaporator, which is part of a compact refrigeration system. The refrigeration unit is used to cool and dehumidify the air stream. The evaporator consists of a direct-expansion coil operated with a thermostatic expansion valve. The evaporator is clearly visible within the ventilation duct as illustrated in Figure 4.7, and the rest of the refrigeration unit-the condensing unit- is placed just underneath the duct.

The refrigerant used is R134a.

Air passing across the evaporator fins is cooled as the refrigerant flowing through the tubes absorbs heat and is boiled (evaporated). Refrigerant flowing through the coil tubes is controlled by a thermostatic expansion valve mounted at the inlet to the evaporator coil. This valve automatically feeds just enough refrigerant into the coil for the refrigerant to be completely converted (boiled) from liquid to gas. The valve is controlled by a temperature-sensing bulb mounted on the coil outlet (suction) connection.

The evaporator itself is complete with an angled draining tray at the bottom. During the dehumidification experiment, condensate can be collected and measured with a graduated cylinder.

Figure 4.7: Evaporator assembly

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CONDENSING UNIT

The condensing unit shown in Figure 4.8, located below the ventilation duct, incorporates a compressor and a condenser. The compressor is used to compress gaseous refrigerant leaving the evaporator, and in the fan cooled condenser the refrigerant gives away the heat gained in the evaporator. The condensing unit also incorporates a refrigerant collector, filter/dryer, sight glass and high/low pressure cut-out for safety purposes.

Figure 4.8: Refrigeration unit assembly

HUMIDIFIER

Humidification is provided by a water boiler of 5 L total volume as illustrated in Figure 4.9. Steam is generated when the water is boiled using the electric element, (2 kW). The boiler is made of plastic and includes a tube which delivers steam to the air duct. It also includes a drain valve, and can be refilled manually through the filler cap and refill lance. Distilled water is recommended in order to avoid scaling of the vessel and duct.

The boiler incorporates a cut-out switch, which prevents the electrical element from overheating if the water level falls too low. If this occurs, wait 2 minutes and refill boiler, the cut off will self reset and steam can be produced again with 5 -12 minutes.

Power to the boiler heaters can be remotely controlled and monitored using the Armfield RA2 Software.

Figure 4.9: Boiler assembly

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AIR VELOCITY SENSOR

The air velocity in the duct is measured by the air velocity transmitter shown in Figure 4.10. This operates on the hot film anemometer principle, using special thin film. It has very good accuracy at low air velocities. The working range is 0 to 10 m/sec and the response time can be up to 4 seconds at constant temperature. Therefore it is important to obtain steady conditions in order to have stable velocity measurement. Steady state in the system is usually obtained after about 15 minutes.

The velocity transmitter is mounted in the duct in the best position to measure the average air velocity. Care should be taken to ensure the correct angle between the sensor head and the air flow.

Figure 4.10: Air velocity sensor

TEMPERATURE / RELATIVE HUMIDITY SENSOR

Temperature and Relative Humidity (T/RH) sensors (see Figure 4.11) are located at every stage of operation. There are 4 T/RH sensors in total: at the duct inlet, before the evaporator, after the evaporator and at the duct outlet. Temperature and Relative Humidity is measured by the sensor. The RH sensor is a water resistant type so that it can operate in the range from 10 to 100% RH.

Figure 4.11: Temperature/Relative Humidity (T/RH) sensor block

For improved accuracy, each RH sensor is provided with a manufacturers’ calibration certificate. The values on this certificate should be entered into the software.

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DATA LOGGER/EQUIPMENT CONTROLLER AND SOFTWARE

The Armfield RA2 Air Conditioning Unit is designed to be operated using the RA2-304 software supplied with the equipment. The RA2 Air Conditioning Unit must therefore be connected to a suitable PC running the RA2-304 software. The RA2-304 software also allows data logging of experimental results, and performs some standard calculations on the data.

OPERATION AND SOFTWARE

USING THE SOFTWARE

The RA2-304 Software is powerful Educational and Data Logging Software with a wide range of features. Some of the major features are highlighted below, but the full details on the software and how to use it are provided in the presentations and Help texts provided with the Software

Check that the USB connection is made between the RA2 unit and the PC, and that the RA2 software is installed and running. Check that the circuit breakers and RCD device at the rear of the unit are in the on (up) position. Turn the unit on by pressing the ON/OFF switch on the unit, then click on the Power On switch on the RA2 software mimic diagram.

On starting the software, the user is met by a simple presentation which gives them an overview of the capabilities of the software and explains in simple terms how to navigate around the software and summarises the major facilities complete with direct links to detailed context sensitive ‘help’ texts.

A toolbar is displayed at all times, so users can jump immediately to the facility they require. The toolbar shows a selection of icons (standard for all Armfield Software) and pop-up text naming the icon when the cursor is placed over it.

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OPERATION OF THE HUMIDIFIER

The humidifier boiler should be filled with water before use, and drained after use if the equipment is not to be used again for some time. Distilled water is recommended for filling, in order to avoid scaling of the boiler vessel and duct interior. The equipment is filled through the filling cap using the filling lance. The sight glass in the front of the unit allows the water level to be viewed during filling.

Humidification is controlled from a PC via the RA2 software. A PID controller within the software maintains the boiler setting based on the temperature measured by temperature sensor T5. The temperature Set Point, Proportional Band, and the Integral and Derivative times may be adjusted by the user. Alternatively the boiler power setting may be entered manually as a percentage value, using the same controller window as for the PID settings.

The water level must be monitored during use, and the boiler refilled as necessary to maintain the level. Great care must be taken to avoid scalding from steam if refilling the boiler during use. Do not look directly into the filling lance and wear insulating gloves if available. Allow time for the water to cool before draining the boiler vessel.

OPERATION OF REMOTE CONTROLLER/DATA LOGGER AND SOFTWARE

The Armfield RA2 Air Conditioning Unit is controlled using the RA2 software supplied, which allows real-time monitoring and data logging of all sensor outputs and control of the heaters and refrigeration unit. Recorded results can be displayed in tabular and graph format. The software runs on a Windows™ PC which connects to the RA2 using a USB interface.

Installation of the software is described in the Installation Guide, and the software must be installed before connecting the PC to the RA2. The software may then be run from the Start menu (Start > Programs > Armfield Refrigeration and Air Conditioning > RA2). Operation of the software is described in a walkthrough presentation within the software, and also in the online Help Text accessible via the software Help menu. Operation and setting of specific controls is also provided within the experiments described in this manual.

Mimic Diagram

The equipment is usually controlled from the Mimic Diagram screen in the software. This shows all the sensor outputs, and includes controls for the fan, the heaters, the humidifier and the chiller.

The software also automatically generates a series of ‘Watchdog’ pulses, required by the PLC, ensuring that the hardware shuts down safely in case of a software or communications failure.

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Controlling the Heaters

The heaters are controlled by controllers in the software. Click on the appropriate PID symbol to open the controller window.

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Control can be either closed loop (Automatic) which uses the temperature sensor immediately following the heater as the process variable in a PID loop, or open loop (Manual) where the user defines the percentage time the heaters are ‘ON’ for, and hence the output power.

When performing humidity measurements and investigations it is best to use automatic control as this produces stable temperatures most rapidly, and maintains these conditions by varying the heater power. However when doing quantitative heater power investigations it is better to use Manual control. This allows an accurate measurement of heater power to be made, but does take longer to stabilise.

Controlling the Fan

The fan is controlled from the software using the up/down buttons. The associated air velocity is displayed on the sensor reading box.

DATA LOGGING FACILITIES

Sampling can be Automatic or Manual. In automatic sampling, samples are taken regularly at the requested interval. In manual sampling, single samples are taken at operator request (useful when conditions have to be changed and the equipment let stabilise in the new condition).

The RA2 software defaults to manual data sampling, allowing the operator to take a reading once the equipment has stabilised.

As the data is sampled, it is stored in spreadsheet format, updated as the data is sampled. The table also contains columns for the calculated values. New sheets can be added to the spreadsheet for different data runs. Sheets can be renamed.

Extremely and powerful graph plotting tools are available on the software, allowing the user full choice over what is displayed, including dual y axes, points or lines, displaying data from different runs, etc. The automatic formatting and scaling is normally used but can be overridden.

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USB INTERFACE

The RA2 interfaces to the computer using a USB interface, built into the sensor and instrumentation enclosure. This interface is sometimes referred to as the IFD5 interface.

The use of USB means that any current or projected Windows based PC can be used. There is no need to open the PC or fit anything inside. Even if all the USB ports are full, expanders are very cheap and readily available. The hardware and software are fully compatible with Windows 98, 2000, XP, Vista and 7 operating systems.

SPECIFICATIONS

OVERALL DIMENSIONS

Length: 1700 mm; Depth: 440 mm; Height: 605 mm

ELECTRICAL SUPPLY

Green/Yellow Lead: Ground; Brown Lead: Live (Hot); Blue Lead: Neutral; Fuse Rating: 15 Amps; Voltage: 220-240 Volts; Frequency: 50 Hz.

VENTILATION

The equipment must be situated in a well ventilated environment or in a large room. The laboratory should be a minimum 50m³ in order for the RA2 not to affect the lab air conditions, consequently altering the results.

REFRIGERANT

This equipment includes a sealed unit containing refrigerant R134a (Also known as: HFC-134a; 1,1,1-2 Tetrafluoroethane; Norflurane; Norfluran). This is a common refrigerant introduced to replace CFC (chloro-fluoro-carbon) refrigerants such as R12. R134a is colourless, non-flammable and non-corrosive with a very faint odour, and is safe under normal use as described in this manual.

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OPERATING CONDITIONS

Operating conditions for RA2 are enclosed by the air conditions envelope (refer to psychrometric chart) as follows:

Temperature Operating Range

When operating the RA2 the ambient temperature and humidity must be taken into consideration for the experiments to work effectively. Below is a table outlining the operating conditions for the various components of the RA2:

Temperature [˚C]

Relative Humidity [%]

Pre-HeaterHumidifier /

BoilerDehumidifier /

ChillerRe-Heater

10 — • • •20 — • • • •30 — • • • •40 — • •— 10 • • •— 20 • • •— 30 • • •— 40 • • •— 50 • • • •— 60 • • • •— 70 • • • •— 80 • • • •— 90 • • • •— 100 • • •

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BACKGROUND AND THEORY

BACKGROUND

The changes of air condition that may be investigated with the RA2 are:

• Heating of air • Cooling of air • Humidification of air • Dehumidification of air with cooling (Not Peformed)

The properties of air that may be measured directly by the RA2 sensors and controls are:

• Air velocity • Relative humidity • Temperature (at multiple locations) • Power input (electrical) to each heater unit (preheat, reheat and boiler)

The constants assumed by the software for calculations are:

• Heat capacity ratio (γ) for air: 1.41 @ 20°C [dimensionless] • Heat capacity ratio (γ) for water: 1.33 @ 20°C [dimensionless] • Acceleration due to gravity (g): 9.81 [m/sec²] • Ideal gas constant (R): 8.314472 [J/mol-K] • Constant pressure specific heat (Cp): 1.005 @20°C [kJ/kg-K] • Constant volume specific heat (Cv): 0.715 [kJ/kg-K]

Variables that cannot be measured by the RA2 and must be input from additional measurements are:

• Ambient (atmospheric) pressure

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NOMENCLATURE

Name Symbol Units Notes

Temperature (Dry Bulb) T or DBT [°C ] Measured by sensor

Vapour pressure Pw [Pa]

Saturation pressure Ps [Pa]

Relative Humidity RH [%] RH = Pw / Ps * 100 %

Mixed air velocity V0 [m/sec]

Recirculate air velocity V1 [m/sec]

Humidity Ratio x or ω kg/kg dry air

Heat transfer rate Q.

[W]

Enthalpy change rate DH.

[W]

Work transfer rate W.

[W]

Compressor work W.

comp [W]

Work transfer from fan motor W.

fan [W]

Cross-sectional area of duct A [m2] 0.04m2

Specific air volume a [m3/kg dry air]

Air mass flow rate m.

a [kg/sec dry air]

Vapour mass flow rate m.

w [kg/sec dry air]

Condensate mass flow rate m.

cond [kg/sec dry air]

Refrigerant mass flow rate m.

ref [kg/sec]

Air enthalpy hA,B,C,D [kJ/kg] Measured at points A, B, C, D

Heat transfer rate at reheater Q.

reh [W]

Heat transfer rate at preheater Q.

preh [W]

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PSYCHROMETRIC CHART

Introduction

A psychrometric chart is shown Figure 4.12.

Figure 4.12: Psychrometric Chart

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A psychrometric chart is a graph of the physical properties of moist air at a constant pressure or often equated to an elevation relative to sea-level. The chart graphically expresses how various properties relate to each other, and is thus a graphical ‘equation of state’.

The versatility of the psychrometric chart lies in the fact that by knowing two independent properties of some moist air (at a constant known pressure), the other properties can be determined. Changes in state, such as when two air streams mix, can easily be graphically modeled using the correct psychrometric chart for the location’s air pressure or elevation relative to sea level. For locations at or below 2000 ft (600 m), a common assumption is to use the sea level psychrometric chart.

The most common chart is the “ω-t” (omega-t) chart in which the Dry Bulb Temperature (DBT) appears horizontally as the abscissa and the humidity ratios (ω) appear as the ordinates. This is the type of chart shown in Figure 4.12.

In order to use a particular chart, for a given air pressure or elevation, at least two of the six independent properties must be known (DBT, WBT, RH, Humidity Ratio, Specific Enthalpy, and Specific Volume).

The RA2 measures the Temperature (dry bulb temperature) and the relative humidity at various places along the duct. Thus the ‘state’ of the humid air can be determined for each of the four measurement points by plotting the T and RH measurements on the psychrometric chart.

From the chart it is then possible to determine the Humidity Ratio (x), the Enthalpy (h) and the Specific Volume (v) at each of the measurement points.

GLOSSARY OF TERMS

Dry Bulb Temperature

DBT or T [ºC] is that of an air sample, as determined by an ordinary thermometer, the thermometer’s bulb being dry. On the standard psychrometric chart this is shown horizontally along the abscissa.

Wet Bulb Temperature or Saturation Temperature

WBT, [ºC] is that of an air sample after it has passed through a constant-pressure, ideal adiabatic saturation process, that is, after the air has passed over a large surface of liquid water in an insulated channel. In practice, this is the reading of a thermometer whose sensing bulb is covered with a wet sock evaporating into a rapid stream of the sample air.

Note: the Wet Bulb Temperature has been omitted from the psychrometric chart provided with the RA2 for clarity. It would normally be displayed on the 100% RH line, with gridlines approximately parallel to those of Enthalpy.

Relative Humidity

φ or RH, [%] is the ratio between the actual water vapour pressure and the saturation vapour pressure (the vapour pressure of saturated air at the same temperature). As the actual vapour pressure cannot exceed the saturation pressure, the maximum value for relative humidity (RH) is 100%. It is sometimes considered to be the amount of water in the air compared with the amount of water that the air could contain (at the same temperature) if saturated (100% RH).

Humidity Ratio

ω or x, [kg/kg] is the humidity of air, expressed as a percentage mass of water vapour in a unit mass of dry air sometimes called the mixing ratio.

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Specific Enthalpy

h (kJ/kg) also called heat content per unit mass, is the sum of the internal energy of a thermodynamic system. It is a measure of the useful work that may be done by the air.

Specific Volume

v (m3/kg) also called Inverse Density or volume per unit mass of dry air.

Dew Point Temperature

DP [ºC] is that at which a moist air sample at the same pressure would reach water vapour saturation, i.e. at which water will begin to condense out of air during cooling. This will vary according to the moisture content of the air. At this saturation point, water vapour would begin to condense into liquid water fog or (if below freezing) solid hoarfrost, as heat is removed. The dew point temperature is measured easily and provides useful information, but is normally not considered an independent property. It duplicates information available via other humidity properties and the saturation curve. The dew point temperature has been omitted from the psychrometric chart provided with the RA2 for clarity.

Saturation Vapour Pressure

Ps [Pa] The pressure at which the vapour phase of a material is in equilibrium with the liquid phase of the same material. The saturation vapour pressure varies with temperature. In the case of saturated air (air saturated with water vapour), the saturation vapour pressure is the pressure (at a specific temperature) when the rate of evaporation of water equals the rate of condensation of water, and is also the point at which the relative humidity is 100%.

CALCULATING MASS FLOW RATE

From the continuity equation:

(4.1)

where A and B are two points along the duct. In the experiments that follow, the letter subscripts refer to the positions along the duct as shown below:

Thus, for a simple duct, the mass flow rate is constant through the duct. The air flow rate (F) is measured by the air speed sensor at position D.

The volume flow rate can be calculated to be F x A, where A is the cross section area of the duct.

m.

aA – m.

aB = m.

a

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Therefore the mass flow rate can be expressed as:

(4.2)

where v is the specific volume of moist air per mass unit of dry air and water vapour [m3/kg]; F is the flow rate of the air [m/sec] and A is the area of the duct [m2]. The specific volume can be determined from the psychrometric chart, by plotting the dry bulb temperature and measured RH at the air flow sensor position.

Note: Most standard psychrometric charts show vdry air, not v, but the difference will be small when calculating flow rates.

ENERGY BALANCE AND HEATING EFFICIENCY

Electrical Heater Power = (Voltage)2/ Resistance or (V2/R where R = 132 Ω for the preheater element and R = 264 Ω for the reheater element).

Efficiency = Sensible Air Heating / Electrical Heater power

Note: In an HVAC system it is quite possible to obtain ‘efficiencies’ of > 100% as heat may be gained from the surroundings as well as lost.

REFERENCES

• Armfield Ltd., Air Conditioning Unit - RA2 Instruction Manual, Issue 10, November 2012.

m.

a =F • A

v

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EXERCISE A : PSYCHROMETRIC CHARTS

EQUIPMENT SET UP

Ensure that the equipment and PC have been set up and that the PC is connected and switched on with the RA2-304 software running. The software should indicate ‘IFD: OK’ in the bottom right of the software window, and the red and green USB indicator lights on the electrical console should be illuminated.

Check that the RCCD (circuit breaker) on the electrical console is in the up (OFF) position.

Check that the sensor readings in the software indicate reasonable values.

PROCEDURE

• Switch on the fan to 40%; Set PID1 to control T2 at 28°C; Set PID3 to control T4 at 20°C.

• Switch the chiller on.

• These values are suitable for typical ambient temperatures in the laboratory around 21°C. They can be raised or lowered to suit the actual laboratory conditions.

• Check that the preheat element on the mimic diagram should change between grey and red to indicate the times during which power is being supplied to the heater. Check that the preheat temperature sensor rises then stabilises at approximately the set temperature.

• Check that the velocity sensor reading in the software increases.

• Adjust the sampling configuration by selecting “Sample” from the top menu and “Configure” as manual.

• Allow the system to stabilise for approximately 15 minutes.

• Record the temperature and relative humidity on the data sheet.

RESULTS

1. Based on the temperature and relative humidity at the four positions, estimate the Humidity Ratio (x), the Enthalpy (h) and the Specific Volume (v) at each of the positions using the psychrometric chart.

2. Describe what happens to the Humidity Ratio as the air proceeds down the duct and how it is related to the Relative Humidity.

3. What would happen to the Humidity Ratio if the fan was set to 50%?

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EXERCISE B: SENSIBLE HEATING

THEORY

HEATING OF AIR

The air is heated without adding any additional moisture, so the humidity ratio remains constant.

The vapour pressure of saturated air increases with increasing temperature. Hence the relative humidity of the heated air decreases.

The heating of air in the duct using the preheater can be represented in the following diagram:

MASS BALANCE

From continuity equation:

(4.3)

(4.4)

where m

. aA is the mass flow rate at inlet to duct, m

. aB is the mass flow rate at inlet to refrigerator and m

. aC is

the mass flow rate at outlet of refrigerator.

ENERGY BALANCE

From first law of thermodynamics:

(4.5)

where DQ

. AB is the change in energy between duct inlet and entrance to refrigerator, DH

. is the change in

enthalpy and W.

is the rate of work done by the air.

Since the work transfer rate is zero within the duct, therefore,:

(4.6)

where ha is the enthalpy at duct inlet and hB is the enthalpy at entrance to refrigerator.

m.

aA = m.

aB = m.

a

m.

aB = m.

aC = m.

a

DQ.

AB = DH.

– W.

DQ.

AB = m.

a(hB – hA)

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A similar energy balance can be performed across the refrigerator:

(4.7)

The energy balance across the reheater is illustrated below:

which may be expressed as:

(4.8)

HEAT TRANSFER

The heat transfer between two points may be calculated as in the following equations

Between duct inlet and refrigerator inlet:

(4.9)

Between refrigerator inlet and refrigerator outlet:

(4.10)

where Cpa is the constant pressure specific heat capacity of dry air = 1.0035 kJ/kg

When the apparatus runs at nearly ambient temperatures, external losses or gains are very small and close agreements should be achieved between the enthalpy change and heat transfer.

EQUIPMENT SET UP

Ensure that the equipment and PC have been set up as described in the installation guide, and that the PC is connected and switched on with the RA2-304 software running. The software should indicate ‘IFD: OK’ in the bottom right of the software window, and the red and green USB indicator lights on the electrical console should be illuminated.



DQ.

BC = m.

a(hC – hB)

DQ.

CD = m.

a(hD – hC)

DQ.

AB = m.

aCpa(TB – TA)

DQ.

BC = m.

aCpa(TC – TB)

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PROCEDURE

• Set the fan to 60%; Set the Preheat control to manual and set to 30%; Let the system stabilise.

• Once the system has stabilised record all the sensor readings on the data sheet.

• Increase the Preheat control in steps of 10% until 60%, allowing stabilising and repeat experiment.

• Check that the preheat element on the mimic diagram changes to red to indicate that the heater is in operation. Check that the preheat temperature sensor rises then stabilises at approximately the set temperature. The heater element on the mimic diagram should change between grey and red to indicate the times during which power is being supplied to the heater.

RESULTS

1. Calculate the following for each of the conditions:

a) Mass flow rate

b) Heat transferred into the air

c) Electrical power input to the heater

2. Plot the following graphs:

a) Heat Transfer Vs Change in Temperature (ΔT)

b) Electrical Power Vs Change in Temperature (ΔT)

3. The heat transfer graph should be a straight line, why? The electrical power input of the heater may not be, comment.

4. Does the mass flow rate affect the heat transferred to the air? Does varying the power supplied to the heat have an effect?

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EXERCISE C: HUMIDIFICATION

THEORY

Humidification of the air flow can be represented as in the following diagram:

Mass and energy balances may be performed as described in earlier exercises.

EQUIPMENT SET UP

The boiler is required for this exercise, and should be filled before use to MAX LEVEL (as indicated on the sight glass) with clean, preferably distilled or de-ionised (demineralised), water.

Ensure that the equipment and PC have been set up as described in the installation guide, and that the PC is connected and switched on with the RA2-304 software running. The software should indicate ‘IFD: OK’ in the bottom right of the software window, and the red and green USB indicator lights on the electrical console should be illuminated.



PROCEDURE

HUMIDIFICATION (NO PREHEAT)

• In the software, set the fan to 40%.

• Select the boiler controller (PID). Set the controller to Manual Control and the Manual Output to 100% to run the boiler heater at full power.

• Observe the equipment as the boiler heats the water. As soon as steam appears at the steam lance outlet, decrease the boiler setting to 40%.

• Allow the system to stabilise (approx. 10 minutes).

• Record the sensor data on the data sheet.

• Repeat for boiler setting of 30% and 20%.

• Remember to refill the boiler as necessary.

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HUMIDIFICATION WITH PREHEAT

• Set the boiler to 40%.

• Open the preheat controller window and set the preheater to Auto with a set point approximately 3°C above the current T2 value .

• Allow the system to stabilise and record the sensor data on the data sheet.

• Raise the set point again and record the results on the data sheet.

• Allow the system to stabilise and record the sensor data on the data sheet.

• If draining the boiler after use, remember to first allow sufficient time for the water to cool.

RESULTS

1. Calculate the following for each of the conditions:

a) Mass flow rate

b) Heat transferred into the air

2. Based on temperature and humidity data alone, use the psychrometric chart to determine the change of state (dew point), enthalpy and relative humidity for each condition.

3. What effect would you expect decreasing the boiler setting to have on the relative humidity and on the humidity ratio of the air stream? Was this reflected in the results obtained?

4. Compare the enthalpy to the heat transfer. Compare the results obtained at different boiler power settings and different preheat temperatures.

5. Is there any observable relationship between the relative humidity and the humidity ratio? How is this affected by the boiler setting? What is the effect of heating the air with the preheater?

6. What are the implications of your findings on the use of steam to humidify air? In what situations might both heating and humidification be required? Are there any additional considerations in air conditioning systems that might arise from the use of water vapour and heating?

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DATA SHEETEXPERIMENT 4: AIR CONDITIONING UNIT

Some data are given due to time constraints in the lab.

Atmospheric Pressure [kPa]: 101

EXERCISE A : PSYCHROMETRIC CHARTS

Fan [%] RH1 [%] T1 [°C] RH2 [%] T2 [°C] RH3 [%] T3 [°C] RH4 [%] T4 [°C]

40

EXERCISE B: SENSIBLE HEATING

Fan [%]

Air Flow [m/s]

Pre-heat [%]

Voltage [volts]

RH1 [%]

T1 [°C]

RH2 [%]

T2 [°C]

RH3 [%]

T3 [°C]

RH4 [%]

T4 [°C]

60 30

60 0.73 40 240 21.0 24.5 14.8 29.0 15.6 28.3 16.0 28.2

60 0.73 50 240 20.0 24.9 13.3 30.4 14.8 29.6 14.2 29.5

60 0.73 60 240 20.5 25.1 12.4 31.5 13.4 30.6 13.6 30.5

EXERCISE C: HUMIDIFICATION

Fan [%]

Air Flow [m/s]

Pre-heat [%]

Boiler [%]

Voltage [volts]

RH1 [%]

T1 [°C]

RH2 [%]

T2 [°C]

RH3 [%]

T3 [°C]

RH4 [%]

T4 [°C]

40 - 40 240

40 0.58 - 30 240 19.7 25.5 17.3 26.0 18.4 25.9 18.0 26.0

40 0.58 - 20 240 19.8 25.5 16.9 25.9 17.6 25.8 17.2 25.9

40 0.58

Auto

(Set Point T2 + 3°C)

19.3 24.3 12.6 31.1 13.9 30.2 14.7 30.0 40.0 29.5

40 0.58

Auto

(Set Point T2 + 6°C)

20.0 24.4 11.7 34.7 13.8 33.6 13.7 32.8 36.3 26.9

Faculty of Engineering and Computer Science Expectations of Originality

This form sets out the requirements for originality for work submitted by students in the Faculty of Engineering and Computer Science. Submissions such as assignments, lab reports, project reports, computer programs and take-home exams must conform to the requirements stated on this form and to the Academic Code of Conduct. The course outline may stipulate additional requirements for the course.

1. Your submissions must be your own original work. Group submissions must be the original work of the students in the group.

2. Direct quotations must not exceed 5% of the content of a report, must be enclosed in quotation marks, and must be attributed to the source by a numerical reference citation1. Note that engineering reports rarely contain direct quotations.

3. Material paraphrased or taken from a source must be attributed to the source by a numerical reference citation.

4. Text that is inserted from a web site must be enclosed in quotation marks and attributed to the web site by numerical reference citation.

5. Drawings, diagrams, photos, maps or other visual material taken from a source must be attributed to that source by a numerical reference citation.

6. No part of any assignment, lab report or project report submitted for this course can be submitted for any other course.

7. In preparing your submissions, the work of other past or present students cannot be consulted, used, copied, paraphrased or relied upon in any manner whatsoever.

8. Your submissions must consist entirely of your own or your group’s ideas, observations, calculations, information and conclusions, except for statements attributed to sources by numerical citation.

9. Your submissions cannot be edited or revised by any other student. 10. For lab reports, the data must be obtained from your own or your lab group’s experimental work. 11. For software, the code must be composed by you or by the group submitting the work, except for code

that is attributed to its sources by numerical reference.

You must write one of the following statements on each piece of work that you submit: For individual work: “I certify that this submission is my original work and meets the Faculty's Expectations of Originality”, with your signature, I.D. #, and the date.For group work: “We certify that this submission is the original work of members of the group and meets the Faculty's Expectations of Originality”, with the signatures and I.D. #s of all the team members and the date.

A signed copy of this form must be submitted to the instructor at the beginning of the semester in each course.

I certify that I have read the requirements set out on this form, and that I am aware of these requirements. I certify that all the work I will submit for this course will comply with these requirements and with additional requirements stated in the course outline.

Course Number: _________________________ Instructor: _____________________ Name: _________________________ I.D. # _____________________ Signature: _________________________ Date: _____________________

1 Rules for reference citation can be found in “Form and Style” by Patrich MacDonagh and Jack Bordan, fourth edition, May, 2000,available at http://www.encs.concordia.ca/scs/Forms/Form&Style.pdf.Approved by the ENCS Faculty Council February 10, 2012

NOTES

NOTES

IN CASE OFEMERGENCY REMAIN CALM AND FOLLOW THESE INSTRUCTIONS

Fire/Evacuation

Suspicious Person/Package

Suspicious Package: Do not touch or disturb object, Call Security @ 514-848-(3717), Notify your Supervisor.

Suspicious Person:Do not physically confront the person,Do not let anyone into a lockedbuilding/office,Call Security @ 514-848-(3717), Provide as much information as possible about the person and his or her direction of travel. Hazardous Materials

If an emergency develops or if anyone is in danger, call 514-848-(3717),Move away from the site of the hazard to a safe location,Follow the instructions of Emergency Personnel,Alert others to stay clear of the area,Notify Emergency Personnel if you have been exposed to the hazard or have information about the release.

Power FailureRemain calm and move cautiously to a lighted area, Do not evacuate unless asked to by Emergency Personnel,Do not use candles!For localized outages, contact Security at 514-848-(3717).

Shelter In Place

Medical EmergenciesIn the event of a serious or life threatening injury or illness; From a safe location; call Security immediately at 514-848-(3717),Ensure your personal security before attempting first-aid,Provide the victim appropriate first-aid & comforting,Do not give the victim anything to drink or eat.

*If the injury is the result of a fall or significant trauma: Do not move the victim unless absolutely necessary.

Communication:Shelter-in-Place will be announced by intercom P.A. voice communication,text messaging,Fire alarms will not be sounded.

Procedures:Lock classroom, office and lab doorsif possible, remain quiet and do not enter the hallway,Should the fire alarm sound, DO NOT evacuate the building unless: 1. You have first hand knowledge that there is a fire in the building, 2. You are in imminent danger, or 3. You have been advised by Security or Police to evacuate the building.Crouch down in the areas that are outof sight from doors and windows,Anyone in the hallways are to seekshelter in the nearest classroom,Anyone outdoors on campus should immediately take cover,If safe you can call 514-848-(8800) for more information on the situation.

Fire:If you see smoke or fire activate the nearest fire alarm.Evacuation:Stay calm; do not rush or panicSafely stop your work,Gather your personal belongings;coat, purse, etc...Close and lock your door and windows.Use stairs only; do not use elevatorsor escalators,Once outside, move away from the building.Do not re-enter the building until instructed to do so by Security.

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