Principle and application of automotive air conditioning

Whether the car air conditioning system can operate normally is related to the comfort, economy and safety of car owners. With the development of social economy and science and technology, cars have become an indispensable part of our lives, and the ownership of cars in our country is also increasing, and people's requirements for car comfort are also increasing. Creating a comfortable interior environment for automobiles mainly relies on the air-conditioning technology of automobiles. The development of air conditioning technology for automobiles is an important key to improving the comfort of automobiles. Automotive technology is constantly evolving, and so is automotive air conditioning technology.

1. Structure of automobile air conditioning system

The air conditioning and refrigeration system in the car is generally in the form of compressor drive, which can be divided into two types: non-independent and independent car air conditioning system. A stand-alone car air conditioning system with a compressor driven by a special auxiliary engine that does not suffer from the effects of the main engine. Non-independent automobile air conditioning system, its compressor is driven by the transmission belt of the main engine of the car, in the process of work will cause a certain degree of consumption to the main engine power, and the amount generated in the refrigeration process is related to the change of automobile speed, is a variable refrigeration system. Whether it is a freestanding structure or a non-freestanding structure, the air conditioning system of all cars includes several parts such as expansion valves, compressors, evaporators, electrical controls, liquid reservoirs and condensers.

2. The working principle of the automobile air conditioning system

Generally, the air conditioning system in a car has four aspects of normal operation: The first is to perform compression. First, the compressor needs to suck in the low-pressure and low-temperature refrigerant gases at the evaporator outlet, compress those gases into high-pressure, high-temperature gases, and then discharge them from the compressor. The second is the exothermic process after condensation. The superheated refrigerant gas at high pressure and high temperature is passed through the condenser, so that the temperature and pressure of the gas are reduced. When the temperature of the gas in the condenser reaches about 45°C, the original gas state of the refrigerant will change to a liquid state, and a large amount of heat will be released at the same time. The third is the expansion process of throttling. After the refrigerant liquid with relatively high pressure and temperature is passed into the expansion valve device, the volume will gradually increase, and the temperature and pressure will drop rapidly, and then be removed from the expansion device in the form of mist. Fourth, the endothermic process during evaporation. The mist gas will pass directly from the expansion device into the evaporator, at which point the boiling point of the refrigerant is much lower than the temperature in the evaporator, so the refrigerant liquid will evaporate into gas. Then, during evaporation, a large amount of heat is absorbed from the surrounding area, and the temperature and pressure are lowered again, and it is passed into the compressor.