Temperature entropy (TS ) and Pressure enthalpy (PH ) diagram of vapour compression refrigeration cycle.


 Vapour compression refrigeration system.

There are four fundamental process in vapour compression refrigeration system. We represent these processes on temperature entropy diagram and pressure enthalpy diagram.







1. Compression

Process 1-2   Isentropic compression process

In this process low pressure and low temperature vapour refrigerant enter in compressor and convert in to high pressure and high temperature vapour refrigerant. In figure compression process represented by line 1-2.
In this process entropy remains constant.

2. Condensation.

Process 2-3  constant pressure (isobaric) pressure process

In this process high pressure and superheated vapour refrigerant enter in Condenser and convert in to high pressure liquid refrigerant by removing latent heat. Condensation process is represented by line 2-3 in TS and PH diagram.
In this process pressure remains constant.

3. Expansion.

Process 3-4 Isenthalpic  process

In this process high pressure and high temperature liquid refrigerant enter in expansion device and pressure decrease. Due to pressure decrease temperature also decreases. In this process enthalpy remains constant.

4. Evaporation.

Process 4-1 constant pressure (isobaric) process

In this process low pressure liquid refrigerant enter in evaporator and absorbs heat and convert in vapour form. During this process pressure is constant.

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