Refrigeration cycle (vapour compression refrigeration cycle)

 Vapour compression refrigeration system.

In this cycle low pressure vapour refrigerant convert in to high pressure vapour refrigerant, so it's called vapour compression refrigeration cycle.
In vapour compression refrigeration cycle there are four fundamental process.
1. Compression
2. Condensation
3. Expansion
4. Evaporation




1. Compression.

In this process low pressure and low temperature vapour refrigerant enter in compressor and convert in high pressure and high temperature vapour refrigerant . In compression process -

State of refrigerant- Gas

Pressure - Low pressure to high pressure

Temperature - Low temperature to high temperature

Function - increase refrigerant pressure.

2. Condensation.

In this process high pressure superheated vapour refrigerant convert in to high pressure and high temperature liquid refrigerant.
In condensation process - 

State of refrigerant. - gas to liquid

Pressure - high pressure

Temperature - high temperature

Function - discharge heat of condensation

3. Expansion.

In this process high pressure and high temperature liquid refrigerant convert in to low pressure and low temperature liquid (80%)+ vapour(20%) refrigerant.
In expansion process -

State of refrigerant - liquid

Pressure - low pressure

Temperature - Low temperature

Function - decrease refrigerant pressure to                                     decrease saturation temperature.

4. Evaporation.

In this process low pressure and low temperature liquid refrigerant absorbs latent heat of vapourization
and convert in to low pressure and low temperature vapour refrigerant.
In evaporation process -

State of refrigerant - liquid to gas

Pressure - Low pressure

Temperature - Low temperature

Function - absorbs heat from the cooling space.




 


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