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Refrigeration Cycle Experiment
Abstract:
The aim of this experiment is to construct the Vapour
Compression Refrigeration Cycle on the Pressure-Enthalpy
property diagram, and determine the Coefficient of
Performance by Measuring the temperatures and pressures
of the liquid and gas phases of the refrigerant at various
locations
...


Methodology:

Theory and Analysis:
1
...

2
...

3
...

Absolute pressure of condenser: 𝑃𝑎𝑏𝑠 = 𝑃𝑎𝑡𝑚𝑠 + 𝑃𝑔𝑎𝑢𝑔𝑒 =1
...
45=1
...
026-0
...
326 bar
4
...

5
...

6
...

𝑗

7
...
75 × 10−3 𝑠 𝑜𝑟 𝑤
...
The rate of heat transfer from water to condenser 𝑄𝑐 = 𝑚𝑐 𝐶𝑃 𝑡3 − 𝑡4 = 2
...

Direct substitution from the table
𝐴𝑏𝑠𝑜𝑙𝑢𝑡𝑒 𝑝𝑟𝑒𝑠𝑠𝑢𝑟𝑒 𝑜𝑓 𝑐𝑜𝑛𝑑𝑒𝑛𝑠𝑒𝑟 1
...
After that, the valves have been checked due
Normal Operation which allowed vapour to be drawn from the
evaporator by the compressor and for condensed liquid to
return to the evaporator from the condenser
...
Then, the
evaporator water flow has been sited to approximately 10 g/s
...
At that point, the refrigerant flow
rate has been adjusted for about 1 g/s
...
From the data, the vapourcompression cycle (the large P-h diagram) can be plotted
...
Delivered pressure ratio= 𝐴𝑏𝑠𝑜𝑙𝑢𝑡𝑒 𝑝𝑟𝑒𝑠𝑠𝑢𝑟𝑒 𝑜𝑓 𝑒𝑣𝑎𝑝𝑜𝑟𝑎𝑡𝑜𝑟=0
...
52
10
...

11
...
5

12
...
This efficiency describes the
competence of the isentropic work which is the difference between the predicted point and point 1
over the actual work done by the compressor
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Isentropic efficiency = ℎ7 −ℎ 5 =390−345 = 0
...
Power input to the refrigerant: 𝑃𝑐𝑜𝑚𝑝 = 𝑚𝑟𝑒𝑓 ℎ2 − ℎ1 = 45 , direct substitution from the table
and graph
...
5
...
However it is not a suitable model for
refrigeration cycles since processes 2-3 and 4-1 are not practical
...

And process 4-1 involves the expansion of a high moisture-content refrigerant in a
turbine
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Figure 2- the main four components in the system
Table 1 – investigation of system performance

Data
Evaporator Gauge Pressure, Peg (kN/m2 )
Evaporator Absolute Pressure, Pea (bar)
Evaporator Inlet Water Temperature, t1 (°C)
Evaporator Outlet Water Temperature, t2 (°C)
Evaporator Refrigerant Temperature, t5 (°C)
Evaporator water flow-rate, me (g/s)
Condenser Gauge Pressure, Pcg (kN/m2 )
Condenser Absolute Pressure, Pca (par)
Condenser Inlet Water Temperature, t4 (°C)
Condenser Outlet Water Temperature, t3 (°C)
Condenser Refrigerant Temperature t6 (°C)
Condenser water flow-rate, mc (g/s)
Compressor Discharge Temp, t7 (°C)
Compressor Power Input, Pmech (Watts)
Refrigerant mass flowrate mref (g/s)
Throttle inlet temperature t8 (°C)
Rate of Heat Transfer from Water Qe (w)
Rate of Heat Transfer from Water Qc (w)
Delivered Pressure Ratio
Coefficient of Performance (COP)
Isentropic efficiency of compressor
Power input to the refrigerant (W)

Reference:

Group members:



Ali Khalil jewaid
Mohamed Nabeel Jaafar

value
-70
0
...
3
20
...
5
10
45
1
...
7
30
...
7
6
59
...
0
31
...
7*10^-3
2
...
52
2
...
57
45



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