Aux 2 Unit 8 Q4

The four main components in a simple vapor compression refrigeration cycle are:

1. Compressor:

• Function: The compressor is the “heart” of the system, responsible for circulating the refrigerant and increasing its pressure. It takes in low-pressure, low-temperature refrigerant vapor from the evaporator and compresses it into a high-pressure, high-temperature vapor.
• Refrigerant State Change: Low-pressure vapor -> High-pressure vapor

2. Condenser:

• Function: The condenser is where the high-pressure, high-temperature refrigerant vapor releases heat to the surroundings (usually air or water), causing it to condense into a liquid state.
• Refrigerant State Change: High-pressure vapor -> High-pressure liquid

3. Expansion Valve (or Metering Device):

• Function: The expansion valve controls the flow of refrigerant into the evaporator. It creates a significant pressure drop, causing the high-pressure liquid refrigerant to expand and partially evaporate, resulting in a low-pressure, low-temperature mixture of liquid and vapor.
• Refrigerant State Change: High-pressure liquid -> Low-pressure liquid/vapor mixture

4. Evaporator:

• Function: The evaporator is where the refrigeration effect takes place. The low-pressure, low-temperature refrigerant mixture absorbs heat from the space being cooled, causing the remaining liquid to evaporate completely. This heat absorption cools the surrounding area.
• Refrigerant State Change: Low-pressure liquid/vapor mixture -> Low-pressure vapor

Cycle in Action:

1. The low-pressure refrigerant vapor leaves the evaporator and enters the compressor.
2. The compressor compresses the vapor, raising its pressure and temperature.
3. The high-pressure, high-temperature vapor flows into the condenser.
4. In the condenser, the refrigerant releases heat to the surroundings and condenses into a high-pressure liquid.
5. The high-pressure liquid refrigerant passes through the expansion valve, where its pressure and temperature drop significantly.
6. The low-pressure, low-temperature refrigerant mixture enters the evaporator.
7. In the evaporator, the refrigerant absorbs heat from the space being cooled and evaporates into a low-pressure vapor.
8. The cycle repeats as the low-pressure vapor returns to the compressor.

This continuous cycle of compression, condensation, expansion, and evaporation allows the refrigeration system to transfer heat from a cold space to a warmer environment, thereby providing the desired cooling effect.