This document summarizes a seminar on vapour compression refrigeration. It defines refrigeration as the process of removing heat from a substance at a lower temperature than its surroundings, using external work. It then describes the basic vapor compression refrigeration cycle, which involves compression, condensation, expansion and evaporation of a refrigerant. Key components of the refrigeration system like the evaporator, compressor, condenser and expansion valve are also outlined. Advantages of vapor compression refrigeration like its maturity, low running costs and high coefficient of performance are highlighted, along with some disadvantages related to refrigerant leakage and environmental impact.

1. SEMINAR
ON
“VAPOUR COMPRESSION REFRIGERATION”
GUIDED BY:- PREPARED BY:-
Mr. Devendra Bhandari Ujjwal Nautiyal
B.Tech(ME) II sem
1014366(38)

2. Refrigeration
 Vapour Compression Refrigeration

3. Refrigeration
 Refrigeration is a process of removal of heat from a
substance at a temperature lower than the
surrounding with the aid of external work.
 In a refrigeration system, the rate at which the heat is
absorbed in a cycle from the interior space to be
cooled is called Refrigerating Effect.

4. *In a refrigerator, a medium called Refrigerant
continuously extracts the heat from the
refrigerator which is to be kept cool at
temperatures less than the atmosphere &
finally rejects to it.
*Refrigerant acts as a heat exchange medium.
*e.g.- Ammonia, Freon, Methyl Chloride, Carbon
dioxide, Isobutane.
*

5. Unit of Refrigeration & Ice making
Capacity
 The capacity of a refrigeration system is expressed in
tons of refrigeration which is the unit of refrigeration.
 A ton of refrigeration is the quantity of heat absorbed
in order to form one ton of ice in 24 hours when the
initial temperature of water is 0°c.
 1 Ton of Refrigeration = 210 kJ/min = 3.5kW
 Ice making capacity is the capacity of the refrigerating
system to make ice beginning from water to solid.
 S.I. unit of ice making capacity is kg/hr.

6. The coefficient of performance(briefly written as C.O.P.)
is the ratio of desired effect to the work input.
Mathematically,
(C.O.P.)refrigerator = Desired effect = Q2____
Work Input Q1-Q2
Coefficient of
Performance

7. T1=Tsurr
Source T1
Heat Rejected, Q1
R Work Input,W=Q1-Q2
Heat Absorbed, Q2
T2<Tsurr
Sink T2
Refrigerator
Refrigerator is a
reversed heat engine.
It extracts Q2 amount of
heat from sink & releases
Q1 amount of heat to
source.
Input—Work(Q1-Q2)
Output– Heat

8. PARTS OF REFRIGERATOR
Parts of
Refrigerator
Evaporator Compressor Condenser
Expansion
Valve

9. Types of Refrigeration
System
Refrigeration
System
Vapour
Compression
Refrigeration
System
Vapour
Absorption
Refrigeration
System

10. 11
Type of Refrigeration
Vapour Compression Refrigeration
Refrigeration cycle
Condenser
Evaporator
High
Pressure
Side
Low
Pressure
Side
Compressor
Expansion
Device
1
2
3
4

11. 12
Type of Refrigeration
Low pressure liquid refrigerant in
evaporator absorbs heat and
changes to a gas
Vapour Compression Refrigeration
Refrigeration cycle
Condenser
Evaporator
High
Pressure
Side
Low
Pressure
Side
Compressor
Expansion
Device
1
2
3
4

12. 13
Type of Refrigeration
The superheated vapour enters the
compressor where its pressure is
raised
Vapour Compression Refrigeration
Refrigeration cycle
Condenser
Evaporator
High
Pressure
Side
Low
Pressure
Side
Compressor
Expansion
Device
1
2
3
4

13. 14
Type of Refrigeration
The high pressure superheated gas
is cooled in several stages in the
condenser
Vapour Compression Refrigeration
Refrigeration cycle
Condenser
Evaporator
High
Pressure
Side
Low
Pressure
Side
Compressor
Expansion
Device
1
2
3
4

14. 15
Type of Refrigeration
Liquid passes through expansion device,
which reduces its pressure and controls the
flow into the evaporator
Vapour Compression Refrigeration
Refrigeration cycle
Condenser
Evaporator
High
Pressure
Side
Low
Pressure
Side
Compressor
Expansion
Device
1
2
3
4

15. Advantages
 Very mature technology.
 It has very less running cost.
 It has smaller size for the given capacity of refrigeration.
 It can be employed over a large range of temperatures.
 The C.O.P. is very high.
Disadvantages
 Many systems still use HCFC refrigerants, which contribute
to depletion of ozone layer.
 Initial cost is high.
 The prevention of leakage of refrigerant is the major
problem in vapour compression refrigeration.
16

16. 17
Seminar
on
“Vapour Compression

Refrigeration”
THANK YOU
FOR YOUR ATTENTION