What is the role of the coolant in the chiller

Update:10 Jun 2019

The refrigerant itself circulates continuously in the r […]

The refrigerant itself circulates continuously in the refrigeration system and then achieves cooling through its own state change. The refrigerant vaporizes in the evaporator by absorbing heat from the cooling medium, and transfers heat to the surrounding air or water in the condenser to condense. When the chiller refrigeration cycle system is running, the refrigerant is also inseparable. The refrigerant flows continuously in the chiller circulation system, and its state is constantly changing. Therefore, the state of the refrigerant at each position of the chiller refrigeration cycle system is different. So, what role does the refrigerant play in the chiller?

1. The change of refrigerant in the chiller refrigeration compressor: the refrigerant enters the suction port of the compressor from the end of the chiller evaporator, and completes the process of compressing the refrigerant vapor into superheated steam in the refrigeration compressor. It is also raised from the evaporation pressure to the condensing pressure. Since the compression process of the compressor is instantaneous, the refrigerant vapor at this time does not exchange heat with the outside world. We call it an adiabatic compression process.

 2. Change of refrigerant in the condenser of the chiller: After the superheated steam enters the condenser of the chiller, since the pressure condition does not change, a part of the heat is first emitted, so that the superheated vapor of the refrigerant is cooled to a saturated vapor. Since this time is still under isothermal conditions, the saturated vapor will continue to ventilate and condense and continuously produce a saturated liquid. The longer the condensation time, the more saturated liquid will be, and the saturated vapor will decrease. The end result is that the refrigerant vapor is completely condensed into a saturated liquid.

3. The change of refrigerant in the throttling element of the chiller: Since the refrigerant has become a saturated liquid, when the saturated liquid refrigerant flows through the throttling element of the chiller, the condensing pressure is reduced to the evaporating pressure, and the temperature is lowered. 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 in which the liquid accounts for about 80% and the gas accounts for about 20%, and the small amount of steam is generated by the expansion of the liquid due to the pressure drop.

4. Change of refrigerant in the chiller evaporator: When the refrigerant enters the chiller evaporator, the refrigerant is continuously vaporized under constant temperature conditions due to the heat absorbed by the cooling medium and evaporating continuously, thereby making the liquid Less and less, steam is getting more and more. When the refrigerant liquid is completely vaporized to become saturated vapor, it will be returned to the compressor suction port of the chiller to recirculate the above changes.