Composition and working principle of automotive air conditioning system

The car air conditioning system mainly consists of a refrigeration system, a heating system, ventilation and air purification devices, and a control system. Its structure mainly includes components such as compressor, condenser, liquid storage dryer, expansion valve, evaporator, blower, and air conditioning throttle.

The working principle of automotive air conditioning systems is mainly based on four processes: compression process, heat dissipation process, throttling process, and heat absorption process. Firstly, the compressor sucks in the low-temperature and low-pressure refrigerant gas at the outlet of the evaporator and compresses it into high-temperature and high-pressure gas for discharge. Then, the high-temperature and high-pressure superheated refrigerant gas enters the condenser. Due to the decrease in pressure and temperature, the refrigerant gas condenses into a liquid and releases a large amount of heat. Subsequently, the refrigerant liquid with higher temperature and pressure increases in volume after passing through the expansion device, causing a sharp decrease in pressure and temperature, and is discharged as a mist (small droplets) from the expansion device. Finally, the mist like refrigerant liquid enters the evaporator. As the boiling point of the refrigerant is much lower than the temperature inside the evaporator, the refrigerant liquid evaporates into gas, absorbing a large amount of surrounding heat during the evaporation process. Then, the low-temperature and low-pressure refrigerant vapor enters the compressor. These four processes are carried out repeatedly to achieve the goal of reducing the temperature of the air around the evaporator.

In addition, the control system of the car air conditioning system will output control signals based on the temperature inside the car, evaporator temperature, engine coolant temperature, and other related switch signals detected by various sensors to control the working status of the radiator fan, condenser fan, compressor clutch, blower motor, and its air control motor, in order to achieve automatic temperature control inside the car.

In summary, the automotive air conditioning system provides a comfortable riding environment for passengers, reduces travel fatigue, and creates good working conditions for drivers through its fine structure and complex working principles, ensuring driving safety.