What is the cooling process of evaporator-for-light-vehicles?

The cooling process of an evaporator for light vehicles is a fundamental aspect of the air conditioning (A/C) system. The primary function of the evaporator is to absorb heat from the air inside the vehicle, resulting in a cooling effect. Here's an overview of the cooling process in an evaporator for light vehicles:

Refrigerant Circulation:

The cooling process begins with the circulation of a refrigerant through the A/C system. Common refrigerants include compounds like R-134a or R-1234yf.

Compression and Condensation:

The refrigerant starts as a low-pressure gas in the evaporator coils. It then enters the compressor, where it undergoes compression. Compression increases both pressure and temperature. The high-pressure, high-temperature gas then flows to the condenser.

Condenser Heat Dissipation:

In the condenser, the hot, pressurized refrigerant releases heat to the surrounding air or to a separate cooling system. This causes the refrigerant to condense into a high-pressure liquid.

Expansion Valve or Orifice Tube:

The high-pressure liquid refrigerant then passes through an expansion valve or orifice tube. This component reduces the pressure of the refrigerant, leading to a sudden drop in temperature.

Evaporator Coil:

The now low-pressure, low-temperature liquid refrigerant enters the evaporator coils. The evaporator is typically located inside the vehicle, often in the dashboard.

Heat Absorption from Interior Air:

Warm air from the vehicle's interior is blown over the evaporator coils by a fan. The low-pressure refrigerant absorbs heat from the air, causing the refrigerant to evaporate and turn into a low-pressure gas.

Cooling Effect:

As the refrigerant evaporates, it draws heat from the surrounding air. This heat absorption causes the air to cool down significantly.

Dehumidification:

Simultaneously, moisture in the warm air condenses on the cold surface of the evaporator coils. This dehumidifies the air, reducing humidity inside the vehicle.

Cooled and Dehumidified Air:

The cooled and dehumidified air is then directed into the vehicle's interior through the HVAC (Heating, Ventilation, and Air Conditioning) system ducts.

Refrigerant Return:

The low-pressure gas refrigerant, having absorbed heat in the evaporator, returns to the compressor to start the cycle again.

This cyclical process continues as long as the A/C system is running. The evaporator is a key component in achieving the desired cooling effect inside the vehicle, making it a critical part of the overall climate control system. Proper maintenance and efficient operation of the evaporator contribute to the effectiveness and energy efficiency of the A/C system in light vehicles.