heat transfer lab manual-2014
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HEAT TRANSFER EP315
LABORATOTY MANUAL
Lecturer/Tutor: Mr. Bonavian/Ms Anita/Ms Sahlil Miraz
Name : ______________________________________
ID : ______________________________________
Course : ______________________________________
FACULTY OF ENGINEERING, ARCHITECTURE & BUILD ENVIRONMENT
UCSI UNIVERSITY
2014
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LABORATORY SAFETY RULES:
Laboratory safety is the top priority and this requires all people in the laboratory to be
observing safe practices at all times!
All safety requirements as specified in this section will be strictly enforced. Students arerequired to comply with the following rules when in the lab.
1. Wear suitable attire for lab work. Do not wear loose or bulky clothes, ties or jewelry
when working around rotating equipment. Students with long hair must tie their hair
before entering the lab. Open-toe shoes and sandals are not permitted.
(Lecturer/ instructor reserves the right not to allow students who do not follow this rule
to enter the lab)
2. Eating and drinking in the lab are strictly prohibited.
3. All hand phones must be switch off.
4. Always be punctual. Students later than 15 minutes are not allowed to perform the
experiment.
5. Always follow the instruction of the lab instructor or lecturer before the start of the lab.
6. It is important for each student to follow the procedures given by the laboratory
instructor when conducting laboratory experiment.
7. Clean the bench and return all apparatus to their respective places before you leave the
lab.
8. Before any experiment starts, students must study the information / precaution steps
and understand the procedures mentioned in the given laboratory sheet.
9. Students should report immediately to the laboratory instructor/officer if any injury
occurred.
10. Do not work with electricity under wet condition in laboratory. Electric shock is a serious
fatal error due to human negligence and may cause death.
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Laboratory Reports:
Each student will be responsible for preparing an individual report after completing each
laboratory experiment.
a) Report submissionReports must be submitted 1 week after the experiment. Any unforeseen circumstances
must be reported to the lab instructor immediately. Late submission will not be
accepted.
Fabricating results and plagiarism are strictly prohibited. Strict action will be taken if
student is found fabricating results or copy from others.
b) Report contents
Each report should contain the following:
SectionUCSI University Cover Page
Title of experiment
Objectives of experiment
Introduction
~Provide a scientific background related to the experiment and provides the reader with
justification for why the work was carried out.
Materials and Equipment
~List only the materials and equipment/apparatus used in the experiment.
Result and Calculation
~Present the data obtained from the experiment. The data have to be presented in a clear
and understandable manner.
~All tables must be clearly labeled with numbers and titles.
~All necessary calculations based on the raw data should be provided in this section.
Discussion
~This is most important section where detailed analysis of the experimental data should beprovided. Factors/issues related to the obtained results must be explained.
~Graphic materials based on the experimental data should be presented and discussed in
this section. All graphs must be clearly labeled with numbers and titles.
~Strategies that can use in the discussion:
Compare expected results with those obtained
Explain the results in terms of theoretical issues
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What do the results indicate?
What is the significance of the results?
Relate results to the experimental objectives
Analyze experimental error
What ambiguities exist?
Find logical explanation for problems in the data
Conclusion
~Based on the discussion provided, summarize the key findings in a clear statement.
Additionally, the conclusion can also be used to express views on the weakness of the
experimental design (if there is any), or what is the implication of your conclusion.
References
~List all references used in the preparation of the report.
Information obtained from any source, including the Internet, is covered by copyright law.
Any source referred in the report must be acknowledged, both within the text and at theend of it.
~The format should follow the American Psychological Association (APA) referencing style.
c) Report Assessment
The laboratory components accounts for 10% of the total marks for the subject.
Laboratory report will be assessed based on the following criteria:
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LAB REPORT ASSESSMENT
Items Unacceptable Satisfactory Good Excellent Score
Score 1 2 3 4
Safetymeasure/
Introduction
Precaution areirrelevant or are not
appropriate to theexperiment
Precaution miss atleast one important
consideration; willresult in some risk tostudent safety if notrevised
All major precautionsare adequately
addressed; proceduresadopted are likely toproduce a safeexperiment
Precaution fullyaddressed .
Timeliness Report handed inmorethan two days late
Up to one day late Up to one hour late Report handed in time
Experimentalprocedures
Procedures do notaccurately list thesteps of theexperiment
Procedures are listed,but seem missing someinformation, somesteps are not numberedand/or are inincomplete sentences.
Procedures are listed,important experimentaldetails are covered,some minor detailsmissing
Procedures are listed inclear steps; each step isnumbered and in acomplete sentence.
Result: data,figures,graphs,tables, etc.
Figures, graphs,tables contain errorsor are poorlyconstructed, havemissing titles,captions or numbers,units missing orincorrect, etc.
Most figures, graphs,tables OK, some stillmissing some importantor required features
All figures, graphs,tables are correctlydrawn, but some haveminor problems or couldstill be improved
All figures, graphs, tablesare correctly drawn, arenumbered and containtitles/captions.
Discussion/Observation
Very incomplete orincorrectinterpretation oftrends andcomparison of dataindicating a lack ofunderstanding ofresults
Some of the resultshave been correctlyinterpreted anddiscussed; partial butincompleteunderstanding ofresults is still evident
Almost all of the resultshave been correctlyinterpreted anddiscussed, only minorimprovements areneeded
All important trends anddata comparisons havebeen interpreted correctlyand discussed, goodunderstanding of resultsis conveyed
Conclusion Conclusions missingor missing theimportant points
Conclusions regardingmajor points are drawn,but many aremisstated, indicating alack of understanding
All importantconclusions have beendrawn, could be betterstated
All important conclusionshave been clearly made,student shows goodunderstanding
Appearanceand formatting
Sections out of order,report is nottyped/written usingthe appropriateformat
Sections in order,formatting is rough butreadable
Lab report is mostlytyped/written using theappropriate format, allsections in order,formatting generallygood but could still beimproved
Lab report is typed/writtenin well-formatted, veryreadable.
Spelling,
grammar,sentencestructure
Frequent grammar
and/or spelling errors,writing style is roughand immature
Occasional
grammar/spellingerrors, generallyreadable with somerough spots in writingstyle
Less than 3
grammar/spelling errors,mature, readable style
All grammar/spelling
correct and very well-written
Total Mark
Final ScorePercentage (%)
= (Total Marks / 32 )*10
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EXPERIMENT TITLE:
1. Fourier's Law study for
a. Linear conduction of heat along homogeneous bar.
b. Conduction of heat and overall heat transfer along a composite bar.
c. Effect of a change in cross-sectional area on the temperature profile along a thermal
conductor.
2. Demonstration of the relationship between power input & surface temperature in free and
forced convection
3. Shell and Tube Heat Exchanger
a) Parallel Flow
b) Counter Flowc) Water Temperature Variation
d) Flow Rate Variation
4. The temperature profile and rate of heat transfer for radial conduction through the wall of
cylinder.
5. Concentric Tube Heat Exchanger with Parallel Flow
a) Parallel Flow
b) Counter Flow
c) Water Temperature Variation
d) Flow Rate Variation
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HEAT CONDUCTION STUDY BENCH
The SOLTEQ ® Heat Conduction Study Bench (Model: HE105) consists of two electrically
heated modules mounted on a bench support frame. One module contains a cylindrical metal
bar arrangement for a variety of linear conduction experiments while the other consists of a
disc for radial conduction experiment. Both test modules are equipped with an array of
temperature sensors. Cooling water, to be supplied from a standard laboratory tap is fed to one
side of the test pieces in order to maintain a steady temperature gradient.
The instrumentation provided permits accurate measurement of temperature and
power supply. Fast response temperature probes with a resolution of 0.1°C are used. The
power control circuit provides a continuously variable electrical output of 0-100 Watts.
The test modules are designed to minimize errors due to true three-dimensional heat
transfer. The basic principles of conduction can be taught without knowledge of radiation or
convective heat transfer. The linear test piece is supplied with interchangeable samples ofconductors and insulators to demonstrate the effects of area, conductivity and series
combinations. Contact resistance may also be investigated, and the important features of
unsteady state conditions may be demonstrated.
For linear conduction, an electrical heating element, which comprises of a heat input
section fabricated from brass fitted with an electrical heater, is bonded to one end of a metal
rod (heat source). Another end of the rod, which is also made of brass, is exposed to heat
discharge (heat sink). The outer surface of the cylindrical rod is well insulated; thus yielding
one-dimensional linear heat conduction in the rod once the heating element is switched on.
Thermocouples are embedded in the rod, along its centerline.
For radial conduction, the electrical heating element is bonded to the center part of a
circular brass plate (heat source). The cooling water flows through the edge of the plate that
acts as a heat sink for heat discharge. The other surfaces of the plate are well insulated to
simulate radial heat conduction from the plate center to its edge when the heating element is
switched on. Thermocouples are embedded in the circular plate.
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Linear Conduction Heat Transfer
Fourier’s Law states that:
dx
dT
kAQ (1)
where,
Q = heat flow rate, [W]
k = thermal conductivity of the material,
Km
W
A = cross-sectional area of the conduction, [m2]
dT = changes of temperature between 2 points, [K]
dx = changes of displacement between 2 points, [m]
From continuity the heat flow rate (Q) is the same for each section of the
conductor. Also the thermal conductivity (k) is constant (assuming no change
with average temperature of the material).
Hence,
)(
)(
)(
)(
)(
)(
C
C
S
S
H
H
dx
dT A
dx
dT A
dx
dT A (2)
i.e. the temperature gradient is inversely proportional to the cross-sectional
area.
Figure 1: Temperature distribution with various cross-sectional areas
AC
Q AH
XH XS XC
AC AC
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Radial Conduction Heat Transfer (Cylindrical)
Figure 2: Radial temperature distribution
When the inner and outer surfaces of a thick wall cylinder are each at a uniform
temperature, heat rows radially through the cylinder wall. From continuity
considerations the radial heat flow through successive layers in the wall must be
constant if the flow is steady but since the area of successive layers increases
with radius, the temperature gradient must decrease with radius.
The amount of heat (Q), which is conducted across the cylinder wall per unittime, is:
i
o
oi
R
R
T T Lk Q
ln
)( 2
(3)
Where,
Q = heat flow rate, [W]
L = thickness of the material, [m]
k = thermal conductivity of the material,
Km
W
Ti = inner section temperature, [K]
To = outer section temperature, [K]
Ro = outer radius, [m]
Ri = inner radius, [m]
Ri Ro
Temperature
Distribution
Ri Ro
Ti
To
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EXPERIMENT 1
Part A : FOURIER'S LAW STUDY FOR LINEAR CONDUCTION OF HEAT ALONG
HOMOGENEOUS BAR Objective
To investigate Fourier's Law for the linear conduction of heat along a homogeneous bar
Procedures:
1. Make sure that the main switch initially off. Then Insert a brass conductor (25mm
diameter) section intermediate section into the linear module and clamp together.
2. Turn on the water supply and ensure that water is flowing from the free end of the
water pipe to drain. This should be checked at intervals.
3. Turn the heater power control knob control panel to the fully anticlockwise position and
connect the sensors leads.
4. Switch on the power supply and main switch; the digital readouts will be illuminated.
5. Turn the heater power control. Regulate the heater power between 0-40 watts. After
each change, sufficient time must be allowed to achieve steady state conditions.
6. Take the temperature reading from T1 until T9.
7. Plot the temperature, T versus distance, x. Calculate the theoretical and actual thermal
conductivity.
Note:
i) When assembling the sample between the heater and the cooler take care to
match the shallow shoulders in the housings.
ii) Ensure that the temperature measurement points are aligned along the
longitudinal axis of the unit.
Results:
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Part C: EFFECT OF A CHANGE IN CROSS-SECTIONAL AREA ON THE TEMPERATURE
PROFILE ALONG A THERMAL CONDUCTOR
Objective:
To investigate the effect of a change in the cross-sectional area on the temperature
profile along a thermal conductor
Procedure:
1. Make sure that the main switch initially off. Insert an brass or any other metals
conductor (13mm diameter) section into the linear module and clamp together.
2. Turn on the water supply and ensure that water is flowing from the free end of the
water pipe to drain. This should be checked at intervals.
3. Turn the heater power control knob control panel to the fully anticlockwise position.
4. Switch on the power supply and main switch; the digital readouts will be
illuminated.
5. Turn the heater power control. Regulate the heater power between 0-20 watts. Allowsufficient time for a steady state condition to be achieved before recording the
temperature at all six sensor points and the input power reading on the wattmeter (Q).
6. Plot the temperature, T versus distance, x. Comment on the trend and slope of the
graph.
Note:
When assembling the sample between the heater and the cooler take care to
provide a good surface contact.
Results:
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EXPERIMENT 2: DEMONSTRATION OF THE RELATIONSHIP BETWEEN
POWER INPUT & SURFACE TEMPERATURE IN FREE AND FORCED
CONVECTION
Objectives:
To demonstrate the relationship between power input and surface temperature in free
and forced convection
PART A – Natural Convection Equipment Set-Up:
Wattmeter (Q)
Temperature Indicator
Plate Sensor
Heater
ProbeSensor
Procedures:
1. Remove the fan assembly from the top of the duct.
2. Place the finned heat exchanger into the test duct.
3. Record the ambient air temperature (tA).
4. Set the heater power control to 20 Watts (clockwise).5. Allow sufficient time to achieve steady state conditions before noting the heated plate
temperature (tH) into the table below.
6. Repeat this procedure at 40, 60 and 80 Watts.
7. Plot a graph of power against temperature (tH-tA).
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Result:
Ambient air temperature (tA) = ________oC
PART B – Forced Convection
Procedures:
1.
Place the fan assembly on to the top of the duct.
2. Place the finned heat exchanger into the duct.
3. Note the ambient air temperature (tA).
4. Set the heater power control to 50 Watts (clockwise). Allow sufficient time to achieve
steady state conditions before noting the heated plate temperature (tH).
5. Set the fan speed control to give a reading of 0.5m/s on the thermal anemometer, allow
sufficient time to achieve steady state conditions. Record heated plate temperature.
6. Repeat this procedure at 1.0m/s and 1.5m/s.
7. Plot a graph of air velocity against temperature. ( tH –tA)
Result:
Ambient air temperature (tA) = _______ C
Power input = 50 Watts
Air Velocity
m/s
Plate Temp (tH)
C
tH – tA
C
0
0.5
1.01.5
Input Power
Watts
Plate Temp (tH)
C
tH – tA
C
2040
60
80
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SHELL & TUBE HEAT EXCHANGER
The SOLTEQ HE104-ST Shell and Tube Heat Exchanger has been designed specifically to
demonstrate the working principles of industrial heat exchangers in the most convenient way
possible in the laboratory classroom. The apparatus requires only a cold water supply, three
phase electrical outlet and a bench top to enable a series of simple measurements to be madeby students needing an introduction to heat exchanger design and operation. Experiments can
be readily conducted in a short period of time, with virtually no setting up operations to
accurately show the practical importance of the following:-
Temperature profiles
Co- and counter-current flow
Energy balances
Log mean temperature difference
Heat transfer coefficients
The equipment consists of a shell and tube heat exchanger mounted on a support
frame. Three temperature measuring devices are installed in both the inside and outside tubes
to measure the fluid temperatures accurately. To minimize losses in the system, the hot water
is fed through the inner pipe, with the cooling water in the outer annulus.
Control valves are incorporated in each of the two streams to regulate the flow. The
flow rates are measured using independent flow meters installed in each line.
The hot water system is totally self-contained. A hot storage tank is equipped with an
immersion type heater and an adjustable temperature controller which can maintain a
temperature to within approximately ± 1°C. Circulation to the heat exchanger is provided by apump and hot water returns to the storage tank to be reheated. The cold water required for
the exchanger is taken from the laboratory mains supply.
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Figure 1: Rear view of shell and tube heat exchanger
Figure 2: Front view of shell and tube heat exchanger
16
15
11
10
9
8
17
18
19
21
22
23
20
24
7 6
12
13
14
2526
1
2
3
4
5
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COMMISSIONING
(Refer to Figs. 1 and 2).
Check the drain valve underneath the water storage tank is fully closed (clockwise).
Remove the cover from the storage tank (1) and fill the tank with clean water to within 40mm(about 1.5 inch) from the top.
NOTE: Heater will automatically off if the water level is below the level switch (2) in order to
prolong the heater life.
Replace the cover on the storage tank.
Connect the cold water inlet (24) to a source of cold water using flexible tubing.
Connect the cold water outlet (5) to a suitable drain.
Close the hot water flow control valve (16).
Set the temperature controller (19) to zero on the front panel.
Switch on the pump switch and observe operation of the pump.
Raise the cover on the storage tank and observe circulation of the water through the tank.
Open the hot water flow control valve (16) and allow water to flow through the exchanger until
a steady flow of water is indicated on the hot water flow meter (22).
Open the cold water flow control valve (15). Set the valves V1 – V4 to parallel and co-current
positions alternatively. Allow water to flow through the exchanger until a steady flow of water
is indicated on the cold water flow meter (23).
Close the hot and cold water flow control valves.
Set the temperature controller (19) to an elevated temperature e.g. 50.0°C. Switch on the
heater and observe the heater switch is illuminated indicating power output to the heating
element. Observe the heater in the storage tank and make sure it runs well.
Commissioning is now complete.
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EXPERIMENT 3: SHELL AND TUBE HEAT EXCHANGER
Objective
The experiment aims to demonstrate the working principles of industrial heat exchangers.
Parallel and counter flow arrangements shall be used and the efficiency of the heat exchangerwill be investigated in each case.
PART A – Parallel Flow Arrangement
1. Start the circulation of cold water.
2. Using the proper selector valve arrangement, set the flow of cold water parallel to the
flow of hot water. (Open V1 & V4, close V2 & V3)
3. Switch on the main switch and the pump.
4. Set the temperature controller to 60°C.
*Note: You may initially reduce the cold water flow rate to speed up the temperatureincrease.*
5. Set the hot water flow rate to 2 liters/min and the cold water flow rate to 1.5 liters/min.
6. Enable to temperature to stabilize before recording the temperatures from T1 to T4.
Results:
R
e a d i n g s
TT1
( tHin )
°C
TT2
( tHout )
°C
TT3
( tCin )
°C
TT4
( tCout )
°C
C a l c u l l a t i o n s Power
emitted
W
Power
absorbed
W
Power
lost
W
Efficiency
%
∆tm
°C
U
W/m2 °C
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PART B – Counter Flow Heat Exchanger
1. Open V2 & V4, close V1 & V3
1. Set the temperature controller to 60°C, and the hot water flow rate and cold water flow
rate to 2 liters/min and 1.5 liters/min respectively.
2. Upon reaching steady-state conditions, record the temperature readings from T1 to T4.
Results:
R e a d i n g s
TT1
( tHin )
°C
TT2
( tHout )
°C
TT3
( tCout )
°C
TT4
( tCin )
°C
C a l c u l l a t
i o n s Power
emitted
W
Power
absorbed
W
Power
lost
W
Efficiency
%
∆tm
°C
U
W/m2
°C
PART C – Flow Rate Variation
1. Use a counter flow set up of the heat exchanger.
2. Set the temperature controller to 60°C.
3. Set the cold and hot water flow rate as in the table below.
Results:
R e a d i n g s
Q HL / min
TT1
( tHin )
°C
TT2
( tHout )
°C
TT3
( tCout )
°C
TT4
( tCin )
°C
2.0
3.0
4.0
5.0
C a l c u l a t i o
n s
Q HL / min
Power
emitted
W
Power
absorbed
W
Power
lost
W
Efficiency
%
∆tm
°C
U
W / m2
°C2.0
3.0
4.0
5.0
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PART D – Water Temperature Variation
1. Use a counter flow set up of the heat exchanger.
2. Set both the cold and hot water flow rate to 2 liters/min.
3. Vary the hot water temperatures to 65°C, 60°C, 55°C and 50°C.
4. Upon reaching steady state conditions at each temperature setting, record thetemperatures of T1 to T4.
Results:
R e a d i n g s
Temp
set
°C
TT1
( tHin )
°C
TT2
( tHout )
°C
TT3
( tCout )
°C
TT4
( tCin )
°C
50
55
60
65
C a l c u l a t i o n s
Temp
set °C
Power
emitted
W
Power
absorbed
W
Power
lost
W
Efficiency
%
∆tm
°C
U
W/m2°C
ηC
%
ηH
%
ηmean
%
50
55
60
65
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SUMMARY OF THEORY:
Power emitted = Q H H CpH (THin - THout)
Power absorbed = Q C C CpC (TCin – TCout)
Power lost = power emitted - power absorbed
System efficiency, η = %100emitted power
absorbed power
Log mean temperature difference, ∆tm =
2
1
21
lnt
t
t t
For parallel flow :
For counter flow :
Overall heat transfer coefficient, U =
areat
absorbed power
m
where,
area = Surface area of contact
= p x ODinner tube x Length x tube count
= (3.142 x 0.0032 x 0.508) m² x 55
= 0.281 m²
Temperature efficiencies of the heat exchanger are:
a) for the cold medium
ηC = %100
Cin Hin
CinCout
t t
t t
b) for the hot medium
ηH = %100
Cin Hin
Hout Hin
t t
t t
c) mean temperature efficiency
ηmean =2
HC
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CONCENTRIC TUBE HEAT EXCHANGER
The SOLTEQ HE104 Concentric Tube Heat Exchanger has been designed specifically to
demonstrate the working principles of industrial heat exchangers in the most convenient way
possible in the laboratory classroom. The apparatus requires only a cold water supply, singlephase electrical outlet and a bench top to enable a series of simple measurements to be made
by students needing an introduction to heat exchanger design and operation. Experiments can
be readily conducted in a short period of time, with virtually no setting up operations to
accurately show the practical importance of the following:-
Temperature profiles
Co- and counter-current flow
Energy balances
Log mean temperature difference
Heat transfer coefficients
The equipment consists of a concentric tube exchanger in the form of a 'U' mounted on
a support frame. The external surface of the exchanger is insulated. Three temperature
measuring devices are installed in both the inside and outside tubes to measure the fluid
temperatures accurately. To minimize losses in the system, the hot water is fed through the
inner pipe, with the cooling water in the outer annulus.
Control valves are incorporated in each of the two streams to regulate the flow. The
flow rates are measured using independent flow meters installed in each line.
The hot water system is totally self-contained. A hot storage tank is equipped with animmersion type heater and an adjustable temperature controller which can maintain a
temperature to within approximately ± 1°C. Circulation to the heat exchanger is provided by a
pump and hot water returns to the storage tank to be reheated. The cold water required for
the exchanger is taken from the laboratory mains supply.
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Figure 1: Rear view of concentric tube heat exchanger
Figure 2: Front view of concentric tube heat exchanger
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COMMISSIONING
(Refer to Figs. 1 and 2).
Check the drain valve underneath the water storage tank is fully closed (clockwise).
Remove the cover (1) from the storage tank (4) and fill the tank with clean water to within40mm (about 1.5 inch) from the top.
NOTE: Heater will automatically off if the water level is below the level switch (2) in order to
prolong the heater life.
Replace the cover on the storage tank.
Close the air bleed valves (11, 9) on the top of the heat exchanger.
Connect the cold water inlet (23) to a source of cold water using flexible tubing.
Connect the cold water outlet (24) to a suitable drain.
Close the hot water flow control valve (22).
Set the temperature controller (12) to zero on the front panel.
Switch on the pump switch and observe operation of the pump.
Raise the cover on the storage tank and observe circulation of the water through the tank.
Open the hot water flow control valve (22) and allow water to flow through the exchanger untila steady flow of water is indicated on the hot water flow meter (21).
Open the cold water flow control valve (26). Set the selector valves (19) to parallel and co-
current positions alternatively. Allow water to flow through the exchanger until a steady flow of
water is indicated on the cold water flow meter (27).
Close the hot and cold water flow control valves.
Attach a length of flexible tubing to each of the air bleed valves (11, 9) at the top of the
exchanger. Open each bleed valve and allow water to flow until all air is expelled.
Close both bleed valves and remove the flexible tubing.
Set the temperature controller (12) to an elevated temperature e.g. 50.0°C. Switch on the
heater and observe the heater switch is illuminated indicating power output to the heating
element. Observe the heater in the storage tank and make sure it runs well.
Commissioning is now complete.
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Open – ended experiment
EXPERIMENT 4: THE TEMPERATURE PROFILE AND RATE OF HEAT TRANSFER FOR
RADIAL CONDUCTION THROUGH THE WALL OF CYLINDER
Objective:
To examine the temperature profile and determine the rate of heat transfer resulting
from radial conduction through the wall of a cylinder
Result :
Plot the temperature, T versus distance, r.
Plot the graph temperature, T (k) versus ln r
Calculate the amount of thermal conductivity.
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Open-ended experiment
EXPERIMENT 5: CONCENTRIC TUBE HEAT EXCHANGER
Objective
The experiment aims to design and construct the working principles of industrial heat
exchangers. Parallel and counter flow arrangements shall be used and the efficiency of the
heat exchanger will be investigated in each case.
Result:
Consist of 4 part which are:
PART A – Parallel Flow Heat Exchanger
PART B – Counter Flow Heat Exchanger
PART C – Flow Rate Variation with counter flow condition
PART D – Water Temperature Variation with counter flow condition
You are require to calculate the efficiency of the heat exchanger
Notes:
For parallel flow, V1 & V3 must be open and V2 & V4 must be close.
For counter flow, V2 & V4 must be open and V1 & V3 must be close.
You can use set temperature at 60°C
Cold water flow rate 1.5 liters/min Hot water flow rate 2 liters/min