Useful in learning basic of refrigeration and air conditioning.

1. Refrigeration and air
conditioning
Presented by :
PUNGAL A.M.

2. What is Refrigeration :
 It is defined as the science of providing
and maintaining temperature below
that of surrounding atmosphere.
 It means that continuously extraction
of heat from a body whose temperature
is already below the temperature of its
surrounding.

3. Refrigeration effect :-
It is defined as the rate of
removal of heat from a substance
which is to be cooled.
Coefficient of
performance. (COP) :-
C.O.P is a measure of efficiency
of a refrigeration system and is
defined as
C.O.P= Refrigeration effect
upon input energy

4. Heat pump:
 It is a device which transfer heat from
low temperature to high temperature
by supplying some external work.
 To avoid confusion the efficiency of
heat pump is replaced by coefficient of
performance ( C.O.P)
 If the purpose of heat pump is to take
out the heat from low temperature
source T1 and supply it to a room
temperature T2 for heating then

6. Difference between heat pump
and Refrigerator :

7. Types of Refrigeration System :
 Simple Vapour compression cycle
 Vapour Absorption Cycle

8. Simple Vapour Compression.
System:

9. Components of Vapour
Compression system :
 Compressor
 Condenser
 Receiver
 Expansion Valve
 Evaporator

10. Types of Vapour Compression
Cycles:
 Dry Vapour Compression Cycles
 Wet Vapour Compression Cycles.
i) Wet Compression discharge Dry
saturated ii) Wet Compression
discharge Wet saturated
 Super Heating of Vapour Compression
Cycles
 Subcooling of Vapour Compression
Cycles
 VCC Of Super Heating and Subcooling

11. Application of simple Vapour
compression refrigeration system
 It is used in Ice plant
 It is used in Domestic Refrigerators​

12. Ice plant:

13. Domestic Refrigerator :

14. Simple Vapour Absorption
System (VAS) :

15. Practical Vapour Absorption
System:

16. Advantages of Vapour Absorption
refrigeration system over VCC
refrigeration system:
 No moving parts, no noise , less wear
pump motor is small compared to VCC
 Initial cost is less compared to VCC
 Elimination of having electrical load
 simple in operation
 Automatic Starting and stopping

17. Difference between VAS and
VCC:

18. Psychometric terms :
 Dry Air :- The mixture of Nitrogen the
oxygen niglecting water vapour is
known as Dry Air
 Wet Air :- It is the mixture of Dry Air
and Water Vapour is known as Wet Air
 Saturated Air :- It is the mixture of Dry
Air and Water Vapour and it is said
saturated when it diffused maximum
amount of water vapour depends on
absolute pressure and temperature

19.  Dry Bulb Temperature :- It is the
temperature recorded by ordinary
thermometer with a clean , dry sensing
element when bulb of thermometer is
expose to air
 Wet Bulb Temperature:- it is the
temperature recorded by ordinary
thermometer when it's bulb is covered
by a wet cloth exposed to the air .
 Dew Point Temperature :- It is the
temperature of air recorded by ordinary
thermometer when the mixture present
in air start to condensed

20.  Specific Humidity :- The mass of water
vapour present in 1 kg of moist air it
known as Specific Humidity
 Absolute Humidity :- It is defined as
the mass of water vapour in unit
volume of moist air is called as Absolute
Humidity
 Relative Humidity :- It is defined as the
ratio of actual mass of water vapour in
unit volume of moist air to the mass of
water vapour in the same volume of
saturated Air at the same temperature
and pressure

21. Dalton's low of partial pressure :-
 The total pressure exerted by the mixture
of air and Water Vapour is equal to the
sum of the pressures , which each
constituent would exert , if the occupied
the same space by itself
 Pb = Pa + Pv
 where , Pb = total pressure exerted by an
air vapour mixture
Pa = partial pressure of air
Pv = partial pressure of water vapour

22. Psychometric chart :-

23. Description of Psychometric
process :-
 Sensible cooling
 sensible Heating
 Cooling with Dehumidification
 Heating with Dehumidification​

24. Air conditioning system :-
 Air conditioning may be defined as
simultaneous control of temperature ,
Humidity , motion of air and purity of air
within the enclosed space

25. Window Air Conditioning:-

26. Thank you