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JANUARY (2014)
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UNIVERSITI KUALA LUMPUR (MICET)
MALAYSIAN INSTITUTE OF CHEMICAL AND BIOENGINEERING TECHNOLOGY
LAB MANUAL
SOLAR THERMAL COLLECTOR UNIT
PREPARED BY:
ARASU A/L UTTRAN
AP DR ROBERT THOMAS BACHMANN
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TABLE OF CONTENT
1.0 INTRODUCTION ................................................................................................................................. 3
2.0 SPECIFICATIONS ........................................................................................................................... 5
3.0 EXPERIMENTAL PROCEDURE ....................................................................................................... 7
3.1 Experiment 1 ............................................................................................................................... 7
3.2 Experiment 2 ............................................................................................................................... 8
4.0 REFERENCES ................................................................................................................................ 9
APPENDIX 1 ........................................................................................................................................... 10
APPENDIX 2 ........................................................................................................................................... 12
APPENDIX 3 ........................................................................................................................................... 14
APPENDIX 4 ........................................................................................................................................... 17
APPENDIX 5 ........................................................................................................................................... 20
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1.0 INTRODUCTION
Figure 1.1: Solar thermal system
For solar thermal systems, the most important component is the solar collector. They are
basically two types of system namely the water and air based system depending on the working fluid.
Flat plate solar collector is the most widely used and effective means of collecting solar energy for
applications that require heat at temperatures below 80OC. The technology has been used widely for
domestic and industrial water heating, space heating and drying. A typical flat plate collector as
shown in Figure 2 consist of the following components (a) absorber plate, (b) transparent cover, (c)
thermal insulation, (d) fluid passage and (e) casing.
The absorber is generally a sheet of metal of high thermal conductivity like copper. It is
coated with black paint or given a special coating called selective coating so that it absorbs the
incident solar radiation efficiently and minimises loss of heat by radiation from the collector plate. A
glass of transparent sheet of good quality is fixed about 2-4 cm above the absorber plate. This
prevents convective heat loss from the absorber plate and infra-red radiation from the plate to escape
to the atmosphere. Insulating material is used to cut down the heat loss due to conduction and must be
adequately thick. There are a number of alternatives for removing heat from the collector plate. The
most common method is to fix tubes, called risers, at spacing of about 10-25 cm. These tubes could be
soldered, spot welded, tied with wires and clamped. Good thermal contact between the tubes and the
plate is very important for efficient operation of the collector. These risers are connected to large
pipes called headers at both ends so that heat removal fluid can enter from the lower header and leave
from the upper header. This configuration is called the fin and tube type and is most commonly used.
The heat removal fluid, normally water or oil, flow through these tubes to carry away the heat
received from the sun. In another type of collector, heat removal fluid flows between two sheets of
glass of metal sealed at the edges, the top acting as the absorber plate.
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All parts of the collector are kept in an outer case usually made of metal sheet. There should
be no leakage of air from this case; otherwise, considerable loss of heat from the collector plate to the
ambient can occur. The collector is finally placed on a stand so that the absorber plate is correctly
inclined to the horizontal and receives maximum amount of heat from the sun either during a
particular season or the entire year.
Flat plate solar collectors can be classified into two main divisions based on type of heat
transfer used. Either liquid of gases (most often air) is used in collectors. Liquid heating collectors are
used for heating water and non-freezing aqueous solutions and occasionally for non aqueous heat
transfer liquids such as thermal oils, ethylene glycol etc. Air heating collectors are used in solar
drying or space heating.
The performance of a solar collector can be determined by thermal efficiency. The thermal
efficiency is defined as the ratio of heat gained from the collector over heat input. The rate of heat
gained can be obtained by measuring the flow rate (m) through the collector and the inlet, Ti and
outlet, To fluid temperatures as
Qu = ṁ Cp (To,f –Ti,f) (1)
where Cp is the specific heat of the working fluid at constant pressure. If Ac represents the operative
area of the collector and S is the source intensity, then the efficiency of the collector is
ŋ = ṁ Cp (To,f – Ti,f) / Ac S (2)
The efficiency of a flat plate solar collector is therefore dependent on many factors such as
collector temperature, ambient temperature, source intensity, and mass flow rate. Hence, it is
necessary to carefully specify the conditions under which the efficiency has been calculated. Ideally,
these conditions should be specified in such a manner that the thermal efficiency of a flat plate solar
collector is defined unambiguously and can be reproducibly.
Figure 1.2: Schematic of a plate solar collector
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2.0 SPECIFICATIONS
a) Solar collector
i) Collector 1 (Insulator: Styro foam, Coating: black paint)
ii) Collector 2 (Insulator: Styro foam, Coating: No coating)
b) Light source: Variable intensity 1 kW halogen wide angle lamp
c) Water tank: 50 L, cylindrical stainless steel tank with coils
d) Water pump: capacity-26 LPM maximum at 3.5 m head
e) Transmitters
i) Temperatures transmitter
ii) Flow transmitter (range: 0-10 LPM)
f) Rotameter (range: 0-10 LPM)
g) Digital display
i) Temperature (OC)
ii) Flow rate (percentage of 10 LPM)
iii) Intensity (percentage of 2350 W/m2)
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Figure 2.1: Schematic diagram of Solar Collector Unit (Model: HE171)
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3.0 EXPERIMENTAL PROCEDURE
There are two experiments used for the solar collector investigating the effect of water flowrate
(experiment 1) and light radiation intensity (experiment 2) on heat transfer.
3.1 Experiment 1
Objective
i. To study the effect of water flow rate on the thermal efficiency of the solar collector at
fix light radiation intensity of 450 W/m2
Procedure
1. Install the solar collector no. 3 into the equipment
2. Make sure that there is sufficient water in the stainless steel tank (i.e. at least 70 % full)
3. Check and make sure that HV4, HV5 and HV6 are fully close while HV1, HV2 and HV3
are fully open.
4. Check and make sure that the communication wire between the control panel and the
computer are securely connected to the computer.
5. Switch on the isolator on the wall.
6. Switch on the main switch of the control panel
7. Switch on the computer and the software shall be started automatically
8. Switch on the pump by pressing the START button. Let the water run through HV6 for a
little while to get rid of the air bubbles in the system.
9. Close HV6
10. Adjust HV2 so that FT reads approximately 1.5 L/min
11. Turn on the light by turning the potentiometer on control panel clockwise until the PR
reads approximately 450 W/m2, and let the system stabilize for 1 minute.
12. Monitor the temperatures TT1 and TT4 every 5 min for 30 min. Record the data in the
table provided (Appendix 1).
13. Change the water flow (Appendix 1) by adjusting HV2 and repeat step 12.
14. 14. The experiment is completed at flowrate 6 L/min.
15. Calculate the heat transfer efficiency for each flowrate and plot the graph of efficiency
versus water flow rate.
16. Complete your report (Appendix 4) and submit to Mr Arasu A/L Uttran one (1) week
after date of this experiment. For every day of late submission one (1) mark will be
deducted
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3.2 Experiment 2
Objective
i. To study the effect of light radiation intensity on the thermal efficiency of the solar
collector at a fix flowrate of 2 L/min
Procedure
1. Install the solar collector no.3 into the equipment
2. Make sure that there is sufficient water in the stainless steel tank (i.e. at least 70% full).
3. Check and make sure that HV4, HV5 and HV6 are fully closed while HV1, HV2 and
HV3 are fully open.
4. Check and make sure that the communication wire between the control panel and
computer are securely connected to the computer.
5. Switch on the isolator on the wall
6. Switch on the main switch of the control panel
7. Switch on the computer and the software shall be started automatically
8. Switch on the pump by pressing the START button. Let the water run through HV6 for a
little while to get rid of the air bubbles in the system.
9. Close HV6
10. Adjust HV2 so that FT reads approximately 2 L/min
11. Turn on the light by turning the potentiometer on control panel clockwise until the PR
reads approximately 50 W/m2
12. Let the system run for 1 minute for light intensity reading to stabilize and then start to
record the temperature readings for TT1 and TT4 every 5 min for 30 min or until thermal
equilibrium has been attained. Use the table provided in Appendix 2.
13. Change the PR reading to the next higher value as specified in Appendix 2 and repeat
step 12.
14. The experiment is completed at maximum PR setting of 6.0 (equivalent to 600 W/m2).
15. Calculate the heat transfer efficiency for each light intensity and plot the graph of
efficiency versus intensity.
16. Complete your report (Appendix 4) and submit to Mr Arasu A/L Uttran one (1) week
after date of this experiment. For every day of late submission one (1) mark will be
deducted.
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4.0 REFERENCES
Chopey, N.P “ Handbook of Chemical Engineering Calculations”. 2nd
Edition, McGraw Hill, 1994
Christi J. Geankoplis, “Transport Processes and Unit Operations”, 3rd Edition, Prentice Hall
International Edition, 1995, pp 217-219
Donald Q. Kern, “Process Heat Transfer”, International Edition, McGraw Hill, 1965.
Perry, R.H., Green, D.W. and Maloney, J.O., “Perry’s Chemical Engineering Handbook”, 6th Edition,
McGraw Hill, 1984
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APPENDIX 1
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EXPERIMENT 1
Date : ___________________________
Group ID : ___________________________
Type of collector: __________________________
Mass flow rate : ___________________________
WFR: 1.5 L/min WFR: 3.0 L/min WFR: 4.5 L/min WFR: 6 L/min
Intensity Intensity Intensity Intensity
t
[min]
TT1
[°C]
TT4
[°C]
t
[min]
TT1
[°C]
TT4
[°C]
t
[min]
TT1
[°C]
TT4
[°C]
t
[min]
TT1
[°C]
TT4
[°C]
0 0 0 0
5 5 5 5
10 10 10 10
15 15 15 15
20 20 20 20
25 25 25 25
30 30 30 30
Summary
F
[l/min]
Intensity
[W/m2]
M
(kg/sec]
TT1
[oC]
TT4
[oC]
Qin
[Watt]
Qout
[Watt]
E
[%]
1.5
3.0
4.5
6.0
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APPENDIX 2
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EXPERIMENT 2
Date : ___________________________
Group ID : ___________________________
Type of collector: __________________________
Mass flow rate : ___________________________
Light intensity:1.5
(150W/m2)
Light intensity:3.0
(300W/m2)
Light intensity:4.5
(450W/m2)
Light intensity:6.0
(600W/m2)
t
[min]
TT1
[°C]
TT4
[°C]
t
[min]
TT1
[°C]
TT4
[°C]
t
[min]
TT1
[°C]
TT4
[°C]
t
[min]
TT1
[°C]
TT4
[°C]
0 0 0 0
5 5 5 5
10 10 10 10
15 15 15 15
20 20 20 20
25 25 25 25
30 30 30 30
Summary
F
[L/min]
PR
[W/m2]
TT1
[°C]
TT4
[°C]
Input
[Watt]
Output
[Watt]
E
[%]
1
2
3
4
5
5.7
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APPENDIX 3
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Operative area of the collector : A = 1.48 m2
Working fluid : Water
Specific heat of water (1 bar) : Cp = 4174 J/kgoC
Table A3.1 Steam table
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Sample calculation
Intensity, S = 452.6 W/m2
Flow rate, V = 2 L/min
TT1= 35.6OC
TT4=38.7OC
For example at 350C
ρH2O = 1/ v (Refer appendix A1)
= 1/ 1.006 cm3/g
= 0.994 g/cm3 x 1kg/1000g x 1cm3/0.01L x 1L/0.001m3
= 994 kg/m3
Mass flow rate of water
m = ρ x V
= 994 kg/m3 x 2 L/min x 0.001 m
3/ L x min/60 s
= 0.0331 kg/sec
Heat input to the collector:
Qin = A x S
= 1.48 m2 x 452.6 W/m
2
= 669. 8 W
Heat output to the collector
Qout = m Cp (TT4-TT1)
= 0.0331 kg/s x 4174 J/(kg K) x (3.1 K)
= 428.3 W
Efficiency of the collector
Ŋ = (Qout / Qin) x 100%
= (428.3 W/ 669.8 W) x 100%
= 63.9 %
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APPENDIX 4
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LAB REPORT (OUTLINE)
Table of content [1 Mark]
List of figures, tables, appendices [3 Marks]
Labelling of pages, figures and tables [3 Marks]
References (complete, correct format) [2 Marks]
1.0 Introduction: Theory including at least two (2) factors influencing the heat transfer in solar-
thermal devices, one (1) schematic diagram of a solar-thermal device, and a brief discussion of two
(2) advantages and two (2) disadvantages of solar-thermal devices (no references no marks!)
[9 Marks]
2.0 Objective: Refer manual [1 Mark]
3.0 Materials and methods:
3.1 List of materials (equipment, chemicals) [2 Marks]
3.2 Method (flow chart, diagram etc) [5 Marks]
4.0 Result: Present data obtained from experiment using
4.1 Summary table [7 Marks]
4.2 Two graphs (one depicting effect of time on TT1 and TT4 temperatures; one depicting effect of
either flowrate (experiment 1) or light intensity (experiment 2) on heat transfer efficiency [4 Marks]
4.3 sample calculations [8 Marks]
5.0 Discussion:
5.1 Compare the main finding of the experiment with the theory [4 Marks]
5.2 In your own words, state at least two (2) factors that can affect the accuracy of the results obtained
[2 Marks]
5.3 Briefly explain how to counter the two (2) problems / factors which can affect the result.
[4 Marks]
6.0 Conclusion: State whether the objective are achieved or not. Provide the main result with and
some recommendation from the experiment. [3 Marks]
7.0 Reference: Please use HARVARD style. For advanced users it is recommended to make use of
referencing softwares such as Mendeley (www.mendeley.com), which is available free of charge with
online tutorial.
8.0 Appendix: The raw data from the experiment should be attached together; all the calculations
should be included as well. [5 Marks]
JANUARY (2014)
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UNIVERSITI KUALA LUMPUR
MALAYSIAN INSTITUTE OF CHEMICAL BIOENGINEERING TECHNOLOGY
LABORATORY REPORT SUBMISSION FORM
To: (Lecturer) Subject code:
From: (Student name)
Student ID No.
Title of Experiment:
Date of Experiment: Date of Submission:
CONTENT Marks
Table of content 1
List of figures, tables, appendices 3
Labelling of pages, figures and tables 3
CONTENT NOTE
Introduction Theoretical of process, description of
equipment 9
Objective List of objectives of experiment 1
Procedure Simplified procedure (start-up, analysis,
experimental) 7
Result Table of results, graph and calculation 19
Discussion Graphical explanation or discussion 10
Conclusion Principal outcomes and recommendation 3
Reference At least three (3) references, complete,
correct format
2
Appendix Raw data during experiment 5
TOTAL: 63
Received by:
........................................
(ARASU S/O UTTRAN)
JANUARY (2014)
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APPENDIX 5
JANUARY (2014)
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LAB SESSION:
Experiment 1: Week 10
Experiment 2: Week 11
Experiment 3 (Gasifier-Demo): Week 12
Grouping
Group ID Student name
G1
55201112027 IRNA BINTI RUSLI
55202112056 SITI NORLAILA FAEIZAH BINTI MOHD RUDIN
55201112073 NOR AMINAH BT MOHD KHALIL
G2
55201112100 NUR SYAFIQAH BINTI HASSAN
55201112125 MOHAMAD HANIF BIN YUSOF
55201112097 NAVINC RAJAMOHAN
G3 55201112102 NOR ATHIRAH BINTI MOHD YUNUS
55201113628 MUHAMAD HAFIZ BIN OTHMAN
G4
55203211324 MOHD SYAFIQ BIN MOHD ROSLI
55201113471 MATHIAS ANAK JOHN
55201112096 MUHAMMAD AZFFAR BIN MOIDEEN
G5
55201112112 NOR HISHAM BIN AHMAD
55201112127 NUR SYAFIQAH BINTI ABDUL ARIS
55201210218 AHMAD ZHAFIR BIN MUHAMAD SHUKRI
G6 55204112015 NUR HIDAYAH BT KAMARUDDIN
55201112028 MUHAMMAD SAIDINA ALI BIN ARIFFIN
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