State change of refrigerant in the working principle of industrial chiller

Date:Apr 02, 2020

If the refrigeration system of industrial refrigeration units is classified by the compression method, there are single-stage compression, double-stage compression, and cascade refrigeration. Among them, the application of single-stage compression refrigeration in industrial chiller is a more common and basic way. How does the state of the refrigerant (refrigerant) change during the refrigeration process?

    The low-pressure refrigerant vapor enters the compressor, is compressed into high-pressure superheated vapor, and then enters the condenser for condensation. The condensed high-pressure liquid refrigerant expands and throttles into low-pressure refrigerant wet steam through the thermal expansion valve, enters the evaporator and absorbs heat and vaporizes it, and the low-pressure refrigerant vapor is sucked into the compressor again into the next refrigeration cycle. The refrigerant completes the processes of compression, condensation, throttling and evaporation in the four components of the compressor, condenser, expansion valve and evaporator, forming a complete refrigeration cycle.

Refrigerant compression process

    After the low pressure refrigerant vapor enters the compressor from the end of the chiller evaporator and is compressed to perform work, its pressure quickly rises to the condensing pressure. Since the refrigerant vapor is compressed and discharged in an instant, the heat is not transferred to the external environment. It can be considered as an adiabatic compression process.

Refrigerant condensation process

    After the high-pressure superheated steam of the refrigerant enters the condenser of the industrial chiller, the condenser will continuously take out the heat in the refrigerant, so that the refrigerant is converted into saturated steam from the high-pressure superheated steam, and becomes a saturated liquid refrigeration during the continuous condensation process Agent.

Refrigerant throttling process

    When the saturated liquid refrigerant passes through the throttling device of the industrial chiller such as the capillary tube and the thermal expansion valve, the pressure of the refrigerant is quickly released, and the temperature of the refrigerant is gradually reduced to the evaporation temperature. At this time, the refrigerant (refrigerant) is in a state in which both the gas phase and the liquid phase coexist, but the refrigerant liquid accounts for the majority, and the refrigerant vapor accounts for a relatively small part.

Refrigerant evaporation heat absorption process

    After the refrigerant enters the evaporator of the industrial chiller from the throttling device, the gas-liquid mixture continuously absorbs heat from the circulating refrigerant and vaporizes into a gaseous refrigerant. The refrigerant (water, glycol or brine) is continuously cooled. The cooling capacity is output to the application equipment, and the evaporated refrigerant is sucked into the compressor for the next compression cycle.


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