What is the working principle of car air conditioning?

2 Answers
MacRuth
07/23/25 11:25pm
The working principle of car air conditioning mainly consists of the following four processes: 1. Compression process: 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, which is then discharged from the compressor. 2. Heat dissipation process: The high-temperature and high-pressure superheated refrigerant gas enters the condenser, where it condenses into a liquid due to the reduction in pressure and temperature, releasing a large amount of heat. 3. Throttling process: The higher-temperature and higher-pressure refrigerant liquid passes through the expansion device, causing its volume to increase, and its pressure and temperature to drop sharply, exiting the expansion device in a mist form (fine droplets). 4. Heat absorption process: The mist-like refrigerant liquid enters the evaporator, where, since the boiling point of the refrigerant is much lower than the temperature inside the evaporator, the refrigerant liquid evaporates into a gas. During the evaporation process, it absorbs a large amount of surrounding heat, and then the low-temperature and low-pressure refrigerant vapor re-enters the compressor. This cycle repeats continuously, thereby achieving the purpose of lowering the temperature of the air around the evaporator.
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KingLee
08/10/25 7:19pm
The working principle of car air conditioning is quite fascinating. At its core is a compression cycle system: after the compressor starts, it compresses the refrigerant into a high-temperature, high-pressure gas. This gas flows through the condenser located at the front of the car, where the fan blows away the heat, causing the gas to cool and turn into a liquid. The liquid refrigerant then passes through an expansion valve to reduce pressure and enters the evaporator, where it rapidly evaporates and absorbs heat, cooling the air that passes through. The fan then delivers this cooled air into the cabin, while the refrigerant returns to the compressor to start the cycle anew. The whole process is like a small refrigerator, but it's important to regularly clean the AC filter to avoid clogging, which can reduce cooling efficiency and increase fuel consumption. Modern car models also incorporate electronic controls to automatically adjust airflow, ensuring comfort while saving fuel.
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