EPT 201 Thermodynamics
Experiment 2 : Marcet Boiler
Laboratory Module
EXPERIMENT 2
Marcet Boiler
1. OBJECTIVE
2. INTRODUCTION
3. COMPONENT AND EQUIPMENT
4. PROCEDURE
5. RESULTS
6. DISCUSSION / EVALUATION AND QUESTION
7. CONCLUSION
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EPT 201 Thermodynamics
Experiment 2 : Marcet Boiler
Laboratory Module
EXPERIMENT 2
Marcet Boiler
1. OBJECTIVE
1.1 To obtain a relationship between the pressure and temperature of saturated steam,
in equilibrium with water, at all pressure between atmospheric and 10 bar (150
lb/in2 ).
1.2 To compare between calculated values from experiment data to the data obtained
from steam table for vfg and hfg .
2. INTRODUCTION
2.1 Background
The study of the laws that govern the conversion of energy from one from to
another , the direction in which heat will flow , and the availability of energy to do work.
It is based on the concept that in an isolated system anywhere in the universe there is
a measurable quantity of energy called the internal energy (U) of the system. This is
the total kinetic and potential energy of the atoms and molecules of the system of all
kinds that can be transferred directly as heat; it therefore excludes chemical and
nuclear energy. The value of U can only be change if the system ceases to be isolated.
In this circumstances U can change by the transfer of mass to or from the system, the
transfer of heat (Q) to or from the system, or by work (W) being done on or by the
system.
Marcet Boiler has been developed for investigating the relationship between the
pressure and temperature of saturated steam, in equilibrium with water, at all pressure
between atmospheric pressure and 10 bar ( 150 lb/in2 ) . The measure value of the
slope of the graph ( dT/dP )SAT obtained from the practical results can be compared
with corresponding values calculated from the data in steam tables.
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EPT 201 Thermodynamics
Experiment 2 : Marcet Boiler
Laboratory Module
Clausius ( 1822-1888 ) the German Physicist and one of the founders of
Thermodynamics was instrumental in deriving the relevant Clausius-Clapeyron
relationship:
Therefore,
the value of vg is much larger than vf , then :
where :
Vf = specific volume of water
Vg = specific volume of steam
hf = enthalpy of water
hg = enthalpy of steam
hfg = enthalpy of evaporation
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EPT 201 Thermodynamics
Experiment 2 : Marcet Boiler
Laboratory Module
Useful conversion.
1 Pa
1J
=
=
1 N/m2
1 N.m
1 bar
=
105 Pa
1 bar
=
102 kPa
1 K.m3 / kJ
=
100 K / bar
K. m3
=
K . m3
kJ
1 K.m3 / kJ =
103J
x
J
N.m
x
105 N/m2
bar
100 K / bar
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EPT 201 Thermodynamics
Experiment 2 : Marcet Boiler
3.
Laboratory Module
COMPONENT AND EQUIPMENT
Figure 1: Marcet Boiler (Solteq HE 169)
A. Part Identifications List
1
Bench
7
Pressure Gauge
2
Panel
8
Pressure Relief valve
3
Marcet Boiler Vessel
9
Temperature Sensor
4
Temperature Indicating Controller
10
Hand Valve
5
Pressure Indicator
11
Heater
6
Pressure Transmitter
B. Specifications
1. Pressure vessel ; 5 liter capacity made of stainless steel
2. Pressure gauge ; 0 to 20 bar (Bourdon type)
3. Thermometer ; Glass, 0 to 200˚C
4. Transducers ; Temperature and Pressure
5. Operating pressure ; Maximum 15 bar
6. Electrical heater ; 2 kW, immersion type
7. Temperature controller ; thermocouple / PT 100 input
8. Safety ; Temperature controller , pressure relief valve
9. Certification ; Tested at 30 bar , JKJ approved
10. Electrical : 240AC/1-ph/50Hz
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EPT 201 Thermodynamics
Experiment 2 : Marcet Boiler
Laboratory Module
4. PROCEDURE
No.
1
2
3
4
5
Experiment Procedure
Open the hand valve. Then switch on the power supply.
Wait and observe the steam released from the hand valve.
This is to assure there is no air/gas left in the boiler.
Danger: The steam is hot; DO NOT stay near to the hand valve.
After steam is released about 1 minute, close and lock the hand valve and
continue the heating process until the pressure gauge reaches the maximum
reading of 10 bars.
During heating process, pressure and temperature will increase. Take both the
temperature readings started at 1 bar and continue the reading until 10 bar.
Record your readings in table 1.
Once pressure increase until 6 bars, switched ‘OFF’ the system.
END OF EXPERIMENT
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EPT 201 Thermodynamics
Experiment 2 : Marcet Boiler
Laboratory Module
Name
:____________________________________
Matrix No.
: ____________________________________
Date
:____________________________________
5. RESULTS
Data
: Table 1
Atmosphere pressure
: ___________ bar ,
Atmosphere temperature : _________(˚C)
Table 1
Experimental
Theory
Data (experiment)
Result
Data (steam table)
Absolute
Pressure,
P
Temperature
Reading,
T
Pressure
difference,
dP
Temperature
difference,
dT
Measured
slope
dT/dP
Steam
specific
volume,vg
(bar)
(0C)
(bar)
(0C)
(K/bar)
(m /kg)
3
Enthalphy
of
evaporation
Result
Calculated
slope
T. vg / hfg
hfg
(kJ/kg)
(K/bar)
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
10.0
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EPT 201 Thermodynamics
Experiment 2 : Marcet Boiler
Laboratory Module
1. Plot a graph of Temperature (0C) v/s Absolute Pressure (bar). Label your
graph.
2. Show the dT and dP at data between pressure 3 bar to 3.5 bar in the graph.
Measure the slope and compare to your theory result.
3. Show all your calculation in separate sheets.
6. DISCUSSION / EVALUATION & QUESTION
6.1
Discuss experimental results. You may use below guidelines:
(Include a discussion on the result noting trends in measured data, and comparing measurements
with theoretical
predictions when possible. Include the physical interpretation of the results and graphs, the reasons on deviations of your
findings from expected results, your recommendations on further experimentation for verifying your results, and your
findings)
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EPT 201 Thermodynamics
Experiment 2 : Marcet Boiler
Laboratory Module
6.2
Why we need to release the air/gas from the equipment before the experiment?
6.3
Compare the experimental result with theoretical result. Give your comments.
6.4
Defined the relationship between the pressure and temperature?
6.5
If we increase the pressure, what will happen to the temperature?
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EPT 201 Thermodynamics
Experiment 2 : Marcet Boiler
7.
Laboratory Module
CONCLUSION
Based on data and discussion, make your overall conclusion by referring to experiment objective.
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