The basic composition and working principle of automobile air conditioning refrigeration system.
As shown in figure 1, the refrigeration system of automobile air conditioning is mainly composed of compressor, condenser, drying filter, expansion valve, condensing fan, evaporator, blower and refrigerant.Each component is connected by a copper tube (or aluminum tube) and a high pressure rubber hose to a closed system.
When the refrigeration system works, the refrigerant circulates in different states in this closed system, and each cycle has four basic processes.
Low temperature low pressure at the outlet of the suction evaporator of the compressor (about0！ 0.15mpa）The refrigerant gas is compressed into high temperature and high pressure (about 70~80!, 1.5mpa gas discharge compressor.
High temperature and high pressure superheated refrigerant gas enters the condenser, and the air is exchanged with the car.Refrigerant gas condenses into liquid (about 40~50!,1.50MPa）, and give off a lot of heat.Then go into the drying and filtering drying filter.
The expansion process.
The expansion valve has throttling function, and the high-pressure refrigerant liquid expands after expanding the valve, and its pressure and temperature drop sharply, so that the refrigerant liquid becomes low pressure and low temperature (about -5!(0.15MPa) the mist (small droplets) of the liquid discharge expansion valve into the evaporator.
After throttling, the low-pressure cryogenic refrigerant liquid enters the evaporator, so the boiling point of the refrigerant is much lower than that of the evaporator, so the refrigerant liquid evaporates into a gas.
The refrigerant absorbs the heat of the car in the process of evaporation, and then the refrigerant gas at low temperature and low pressure enters the compressor.