Vapour compression refrigeration cycle uses four main components - a compressor, condenser, expansion valve, and evaporator. The refrigerant is compressed into a hot, high-pressure gas (1-2), condensed into a liquid in the condenser (2-3), expanded through the throttle valve into a cold, low-pressure liquid-vapour mixture (3-4), and evaporated in the evaporator (4-1) to complete the cycle. The coefficient of performance (COP), a measure of efficiency, is calculated as the refrigeration effect divided by the work input. Increasing the evaporator or condenser pressure decreases COP, while superheating may increase or decrease COP depending on the refrigerant

1. CAREER POINT UNIVE
MAJOR ASSIGNMENT
Vapours Compression Refrigeration Cycle

2. Table of Content
• Refrigeration
• Refrigerant
• Vapour compression cycle
• Effect
• Cop
• Merit
• Demerit
• Advantage
• By studying of research paper

3. Refrigeration
• Refrigeration is the process of producing of lower temperature
compare to the surrounding temperature to maintain the
lower temperature.
• For example : vapour compression cycle, vapour absorption
cycle, gas refrigeration cycle.

4. Refrigerant
• Refrigerant are the substance which are used for producing
lower temperature .for example ammonia,water,air,R-12,R-
22,R-134.
Refrigeration effect: It is the amount of heat which is to be
extracted from the storage space in order to maintain lower
temperature is called desire effect of refrigeration system.

5. V c cycle
Vapour compression Refrigeration System:
There are four component in Vapour compression cycle.
1. Compressor:- Compresses the refrigerant to high pressure and temperature
from low pressure and temperature.
2. Condenser:- The latent heat of refrigerant is removed by circulating water or
atmospheric air.
3. Expansion Valve:- In the throttle valve where the pressure is reduced at a
controlled rate.
4. Evaporator:- A liquid-Vapour mixture refrigerant then enters the evaporator
at low pressure where the latent heat of evaporation is converted into vapour and
the cycle repeats.

6. Fig:- The P-h diagram is another convenient
diagram often used to illustrate the refrigeration
cycle.

7. COP Of V.C. Cycle
Apply Steady flow energy equation ( Neglect K.E & P.E changes)
1. Compressor:
Q1-2 + C1
2/2 + Z 1 + h1 = W1-2 + C2
2/2 + Z 2+ h2
W1-2 = - ( h2 – h1)
2. Condenser:
Q2-3 + C2
2/2 + Z 2 + h2 = W2-3 + C3
2/2 + Z 3+ h3
Q2-3 = - (h2 - h3)
3. Throttle Valve:
Q3-4 + C3
2/2 + Z 3 + h3 = W3-4 + C4
2/2 + Z 4+ h4
h3 = h4 (Isenthalpic process)
4. Evaporator:
Q4-1 + C4
2/2 + Z 4 + h4 = W4-1 + C1
2/2 + Z 1+ h1
Q4-1 + h4 = h1
Q4-1 = h1 – h4

8. COP
Co-efficient of Performance: It is the ratio of net refrigerating effect to the work
required to produce that effect.
Co-efficient of performance = Refrigerating effect/ Work input
= ( h1 – h4 ) / (h2 – h1)

9. Effects of variation of properties on the performance
of Vapour compression cycle:
Case 1:- Decrease in Evaporator:
RE= h1-h4
Win=h2-h1
COP= RE/Win

10. Effect
Reduction in Refrigeration effects
Increase in work input
Decrease in COP
Decrease in volumetric efficiency due to increase in pressure
ratio.

11. RE= h1-h4
Win=h2-h1
COP= RE/Win
• Case 2:- Increase in condenser pressure

12. Effect
Reduction in Refrigeration effects
Increase in work input
Decrease in COP
Decrease in volumetric efficiency due to increase in pressure
ratio.

13. RE= h1-h4
Win=
COP= RE/Win
• Case 3:- Superheating

14. Effect
Increase in Refrigeration effect
Increase in work input due to temperature at the inlet to
compressor increase.
COP may increase or decrease depending on the refrigerant. In
case of R- 12 superheating result in increase in COP where as in
case of NH3 superheating results in decrease in COP.

15. MERIT
• Cop is high.
• Size of evaporator is small.
• Evaporator temperature adjustment is small.
• Easily available .
• It is used for small places like shops.

16. Demerit
• Initial cost is high.
• Inflammability
• Leakage
• Toxicity

17. Advantages
• Lot of heat can be removed (lot of thermal energy to change
liquid to vapors).
• heat transfer rate become high(temperature of working fluid
much lower than what is being cooled).

18. Studying by research paper
• By getting result of R134a is a best refrigerant among all
refrigerant.
• Because COP is lower as compare to other refrigerant
• That’s why R-134 is a eco-friendly in nature .

19. Conclusion
• At finally we conclude that v c cycle is work on high grade
energy and it is where used there is small space
• It is used for making environment cool