What is the principle of automobile intake heating?

When the engine is running, the amount of air flowing through the intake pipe changes due to the change of throttle opening, which leads to the change of vacuum degree (negative pressure). The intake pressure sensor is made by using this principle.

The intake pressure sensor is designed based on the piezoelectric principle and consists of a sealed elastic diaphragm and an iron core. The diaphragm and the iron core are accurately placed in the coil. When the diaphragm is subjected to the absolute intake pressure in the intake pipe, it will be deformed, so that the induced electromotive force corresponding to the absolute pressure is generated in the coil due to electromagnetic induction. This induced electromotive force is proportional to the load.

Extended data:

1. The induced electromotive force is linearly related to the basic fuel injection quantity and inversely related to the basic ignition advance angle. The temperature sensing element of air temperature sensor is composed of semiconductor thermistor with negative temperature coefficient, and the resistance is tested by special measuring circuit.

The resistance is small at high temperature and large at low temperature. ECU provides it with 5V DC power supply, which makes the product of resistance and current generate voltage signal. Because the resistance changes with temperature, the signal voltage will also change. When the temperature is high, the tendency of engine deflagration increases. Fuel injection quantity and ignition advance angle should be corrected or compensated by temperature.

2. The parking heating system is mainly composed of air intake system, oil supply system, ignition system, cooling system and control system. Its working process can be divided into five working steps: air intake stage, oil injection stage, mixing stage, ignition combustion stage and heat exchange stage.

The working principle of the parking heating system is that a small amount of fuel in the fuel tank is pumped into the combustion chamber of the parking heater, and then the fuel burns in the combustion chamber to generate heat, which heats the engine coolant or air, and then radiates the heat to the compartment through the warm air radiator, while preheating the engine. In this process, it will consume battery power and a certain amount of fuel.

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