The role of refrigerant in air-cooled chillers

The role of refrigerant in air-cooled chillers

The refrigerant itself circulates continuously in the refrigeration system, and then realizes refrigeration through its own state changes. The refrigerant absorbs the heat of the cooled medium in the evaporator and vaporizes, and transfers the heat to the surrounding air or water in the condenser to condense. When the air-cooled chiller refrigeration cycle system is running, the refrigerant is also inseparable. The refrigerant flows continuously in the air-cooled chiller circulation system, and its state is constantly changing. Therefore, the state of the refrigerant in each position of the air-cooled chiller refrigeration cycle system is different. . So, what role does refrigerant play in air-cooled chillers?

　　 1. The change of refrigerant in air-cooled chiller refrigeration compressor

　　The refrigerant enters the suction port of the compressor from the end of the air-cooled chiller evaporator, and completes the process of compressing the refrigerant vapor into superheated vapor in the refrigeration compressor, and the pressure is also increased from the evaporation pressure to the condensation pressure. Since the compression process of the compressor is completed instantaneously, the refrigerant vapor at this time will not exchange heat with the outside world, which is called the adiabatic compression process.

　　2, the change of refrigerant in the condenser of air-cooled chiller

　　After the superheated steam enters the condenser of the air-cooled chiller, since the pressure condition does not change, a part of the heat will be dissipated first, so that the refrigerant superheated steam will be cooled into saturated steam. Because it is still under isothermal conditions at this time, the saturated vapor will continue to emit heat and condense and continuously produce saturated liquid. The longer the condensation time, the more saturated liquid will be and the saturated vapor will decrease. The final result is: all refrigerant vapor condenses into saturated liquid.

　　3, the change of refrigerant in the throttling element of air-cooled chiller

　　Since the refrigerant has all become saturated liquid, when the saturated liquid refrigerant flows through the throttling element of the air-cooled chiller, it will decrease from the condensation pressure to the evaporation pressure, and the temperature decreases from the condensation temperature to the evaporation temperature. The refrigerant flowing out from the outlet of the throttle element becomes a two-phase mixed state with about 80% liquid and 20% gas. The production of a small amount of vapor is the flash gas that appears due to the pressure drop and the expansion of the liquid.

　　4. The change of refrigerant in the evaporator of air-cooled chiller

When the refrigerant enters the evaporator of the air-cooled chiller, due to the heat absorbed by the cooling medium and continuous evaporation, the refrigerant is continuously vaporized under constant temperature conditions, resulting in less and less liquid and more and more vapor many. When the refrigerant liquid is completely vaporized and becomes saturated vapor, it will return to the compressor suction port of the air-cooled chiller to recycle the above changes.