Refrigeration-Vapor compression

Refrigeration-Vapor compression

Refrigeration is heat transfer from a low temperature to a high temperature. It cannot take place by itself. Vapor compression refrigeration system is used to achieve it. Its components, their functions and various processes to achieve refrigeration help in understanding the whole system.

Sr.No. System part Process State of the refrigerant Heat gain or heat loss
1. Compressor Compression Super heated high pressure high temperatures vapor refrigerant Heat gain due to work done in compressor
2. Discharge pipe Cooling Slight fall in temperature but still Super heated high pressure high temperatures vapor refrigerant Heat loss to the surroundings
3. Condenser Condensation High pressure high temperature liquid refrigerant Losses latent heat to the condenser cooling medium
4. Receiver Storing of liquid refrigerant High pressure high temperature liquid refrigerant —————-
5. Liquid suction

heat exchanger

Heat transfer between

liquid line and suction pipe

Refrigerant going to compressor is superheated while refrigerant going to expansion valve is sub cooled Heat gained by vapor = heat lost by the liquid refrigerant
6. Liquid line Flow of liquid refrigerant High pressure high temperature  sub cooled liquid refrigerant —————
7. Evaporator Evaporation Low pressure low temperature vapor refrigerant Gains latent heat from the products to be cooled
8. Accumulator Separation of vapor and liquid Low temperature low pressure Vapor refrigerant  goes to the compressor —————-
9. Suction line Heating surroundings

of vapor from the

Super heated Low temperature low pressure vapor refrigerant Gains sensible heat from the surroundings

 

QUESTION ANSWERS

List the parts making the low pressure side of the refrigeration cycle.

  1. Outlet of the expansion valve
  2. Evaporator
  3. Accumulator
  4. Suction line
  5. Suction service valve
  6. Midway of compression

Names of parts making the high pressure side of the refrigeration cycle

  1. Second half of compression
  2. Discharge service valve
  3. Discharge pipe
  4. Oil separator
  5. Condenser
  6. Receiver
  7. Liquid line
  8. Drier cum filter
  9. Inlet of the expansion valve

What are the different names of the high pressure?

  1. Head pressure
  2. Discharge pressure
  3. Condenser pressure

Write different names for the low pressure.

  1. Suction pressure
  2. Back pressure
  3. Evaporator pressure