The function of the car cooling system is to keep the car in the appropriate temperature range under all working conditions. The cooling system of a car is divided into air cooling and water cooling. The air as the cooling medium is called the air cooling system, and the coolant as the cooling medium is called the water cooling system. Usually, the water cooling system consists of a pump, radiator, cooling fan, thermostat, compensation bucket, water jacket in the engine body and cylinder head, and other auxiliary devices. Among them, the radiator is responsible for the cooling of circulating water, its water pipe and heat sink are made of aluminum, aluminum water pipe is made into a flat shape, the heat sink is corrugated, pay attention to the heat dissipation performance, the installation direction is perpendicular to the direction of air flow, as far as possible to achieve small wind resistance and high cooling efficiency. The coolant flows inside the radiator core, and the air passes outside the radiator core. The hot coolant cools because it dissipates heat to the air, and the cold air heats up because it absorbs the heat emitted by the coolant, so the radiator is a heat exchanger.