Steam compression refrigeration is a widely used refrigeration technology, Maipt machinery involved in the refrigeration unit

Steam compression refrigeration is a widely used refrigeration technology, MAIPT machinery involved in the refrigeration unit, the most common refrigeration principle of the way to manufacture refrigeration equipment, the following is its relevant introduction:

Basic principle

Based on the principle of inverse Carnot cycle, steam compression refrigeration mainly consists of four processes: compression, condensation, throttling and evaporation. Heat transfer from low temperature objects to high temperature objects is realized through the change of refrigerant state. The specific process is as follows:

Compression process: the low temperature and low pressure refrigerant steam after the heat evaporation in the evaporator is inhaled by the compressor, and the compressor does work on it, so that the pressure and temperature of the refrigerant steam rise, and become high temperature and high pressure superheated steam. In this process, the internal energy of the refrigerant steam increases, and the outside world does work on the refrigerant.

Condensation process: high temperature and high pressure refrigerant steam into the condenser, in the condenser and cooling medium (such as water or air) for heat exchange, refrigerant steam to the cooling medium to release heat, gradually cooling itself into high temperature and high pressure liquid condensation. This is an isobaric heat release process in which the temperature of the refrigerant decreases and the state changes from gas to liquid.

Throttling process: the high temperature and high pressure refrigerant liquid is throttled and reduced by the throttle valve, because the throttling process is carried out very quickly, it can be approximately regarded as an adiabatic process, and the pressure and temperature of the refrigerant liquid drop sharply, becoming a low temperature and low pressure wet steam. In this process, the enthalpy value of the refrigerant is unchanged, but due to the reduction of pressure, part of the liquid is vaporized to form a gas-liquid two-phase mixture.

Evaporation process: low-temperature and low-pressure wet steam enters the evaporator, evaporates in the evaporator, absorbs heat from the cooled object or space, reduces the temperature of the cooled object or space, and achieves the refrigeration effect. After the refrigerant absorbs heat in the evaporator, it completely evaporates into low-temperature and low-pressure steam, and then is sucked into the compressor again to start the next cycle.

Main component

Compressor: is the heart of the steam compression refrigeration system, its role is to compress the low temperature and low pressure refrigerant steam into high temperature and high pressure steam, providing power for the circulation of refrigerant in the system, so that the refrigerant can absorb heat and evaporate in the evaporator, and release heat and condense in the condenser.

Condenser: used to condense the high-temperature and high-pressure refrigerant steam discharged by the compressor into a liquid, and dissipate the heat in the refrigerant steam to the outside environment through heat exchange with the cooling medium.

Throttle valve: also known as expansion valve, its role is to throttle the refrigerant liquid at high temperature and high pressure to reduce the pressure and temperature of the refrigerant before entering the evaporator, creating conditions for the evaporation of the refrigerant in the evaporator.

Evaporator: is the refrigerant in which the evaporation of heat absorption components, low temperature and low pressure refrigerant wet steam in the evaporator and the cooling object or space for heat exchange, absorb the cooling object or space heat, so that the cooling object or space temperature is reduced, the refrigerant evaporates into low temperature and low pressure steam.

Application field

Home air conditioning: used to adjust the indoor temperature, to provide people with a comfortable living environment. In summer, the indoor heat is transferred to the outdoor, so that the indoor temperature is reduced; In winter, through the heat pump mode, the outdoor heat is transferred to the indoor, to achieve heating.

Refrigerators and freezers: used to maintain a low temperature environment and extend the shelf life of food and other items. Through the steam compression refrigeration system, the heat inside the refrigerator or freezer is removed, so that the internal space is kept at a lower temperature.

Commercial refrigeration: such as refrigerated display cabinets in supermarkets, cold storage, etc., need precise control of temperature and humidity to store and display a variety of food, beverages, medicines and other items.

Industrial refrigeration: In the chemical, pharmaceutical, electronics and other industries, many production processes require low temperature environment, such as low temperature storage of chemical raw materials, freeze-drying of drugs, cooling in electronic chip manufacturing, etc., steam compression refrigeration system can meet the refrigeration needs of these industrial production.