Subject:- Refrigeration and Air Conditioning

Topic:- Vapor Compression Refrigeration System

Difficulty:- Low

The various processes in this system are as follows: Saturated vapour refrigerant at pE is admitted to low pressure compressor at point 1. Here, refrigerant is compressed is entropically from pE to water intercooler pressure p2. Refrigerant leaving low pressure compressor at point 2 is in superheated state. This superheated vapour refrigerant is now passed through water intercooler at constant pressure, in order to reduce degree of superheat. Line 2-3 represents water intercooling.

Refrigerant leaving the intercooler at point 3 (which is still in superheated state) is compressed is entropically in high pressure compressor to condenser pressure pC. This is shown by process 3-4.

Discharge from high pressure compressor is now passed through condenser which changes state of refrigerant from superheated vapour to saturated liquid as shown by 4-5.

Temperature of saturated liquid refrigerant is further reduced by passing it through a liquid sub-cooler as shown by 5-6. Liquid refrigerant from sub-cooler is now expanded in expansion valve (6-7) before being sent to evaporator (7-1).