Principle of air-cooled fin evaporator

Air-cooled fin evaporator is a common heat exchanger, mainly used in the refrigeration cycle of air conditioning systems. Its principle is based on evaporative cooling and heat conduction.
Refrigerant into the evaporator: Refrigerant (usually liquid) in the refrigeration cycle enters the inlet pipe of the air-cooled fin evaporator and controls the flow of refrigerant through an expansion valve.

Refrigerant evaporation: When the refrigerant enters the inside of the air-cooled fin evaporator, the refrigerant encounters a low pressure and low temperature environment. At this time, the outside of the finned evaporator is blown by a fan over the surface of the evaporator, forming a convection. When the refrigerant is in contact with the fin surface, due to the low temperature of the fin surface, the refrigerant begins to evaporate into a gas. In this process, the refrigerant changes from liquid to gas, absorbing heat from the surrounding environment and achieving evaporative cooling.

Air cooling: The air blown by the fan over the surface of the finned evaporator takes the heat away, forming a cooling effect. In this way, the refrigerant inside the evaporator transfers heat to the air, thereby reducing the air temperature.

Refrigerant outflow: After the cooled air passes through the evaporator, the refrigerant has completely evaporated into a gas, and the temperature is low. At this time, the refrigerant leaves the evaporator through the outlet pipe of the evaporator and continues to circulate to the compressor for the next refrigeration cycle.

The air-cooled fin evaporator evaporates the liquid refrigerant into a gas through evaporation cooling and air convection, and carries out heat conduction through the air blown over the surface of the fin to achieve air cooling. In this process, the refrigerant absorbs the heat of the surrounding environment, thus achieving the effect of cooling the air.