Characteristics of throttling short pipe system in automotive air conditioning

At present, China's automotive air-conditioning is still using a compression refrigeration system, using open or semi-hermetic compressors, high-efficiency evaporators and condensers. In order to make full use of the oncoming wind speed when the car is started, the condenser is often arranged at the front end of the car, and the evaporator is placed at the bottom of the dashboard or inside the vehicle cabin, and the hose is connected in the middle.

For ease of maintenance, the fittings between the piping and the components use O-rings or screws. High temperature, vibration, and corrosion can easily cause leakage of refrigerant. In order to maintain the performance of automobile air conditioners within a certain period of time, liquid storage equipment is usually provided.

The automobile air-conditioning system is divided into a thermal expansion valve system and a throttling short pipe system according to different throttling components. The former configures a liquid storage dryer behind the condenser to store the refrigerant and ensure that the heat expansion valve inlet refrigerant is in the liquid phase; and then A gas-liquid separator is installed in front of the compressor and there is a function of avoiding the liquid hammer of the compressor in addition to the liquid storage. Different liquid storage devices make the throttling short tube car air conditioning system and the thermal expansion valve auto air conditioning system present different performance characteristics.

Whether it is a throttling short pipe system or a thermal expansion valve system, for most in-use cars, it is expected that the new environmentally friendly alternatives should have the following characteristics: (1) Can be used as a direct priming replacement without replacement of zero Parts can still obtain cooling capacity comparable to the original system; (2) no need to replace lubricating oil; (3) global greenhouse effect index is relatively low; (4) can reduce operating costs; (5) can extend the service life of the compressor.