With the development of the times, cars have entered every household as "standard", but today, cars are no longer a means of travel, but more like our good friends. We basically use them both in life and out. So today, let's briefly introduce what turbochargers are!

1. Introduction

The turbocharger is actually an air compressor, which adds air intake through compressed air. It uses the inertia impulse of exhaust gas discharged by the engine to push the turbine in the turbine chamber. The turbine drives the coaxial impeller, which compresses the air sent by the air filter pipe and pressurizes it into the cylinder. When the engine speed increases, the exhaust gas discharge speed and the turbine speed also increase synchronously, and the impeller compresses more air into the cylinder. The increased air pressure and density can burn more fuel. The corresponding fuel amount and the engine speed can be adjusted to increase the engine output power.

2. Structural principle

First of all, let's talk about the basic structure and principle of the turbocharger. The exhaust gas turbocharger is mainly composed of the pump wheel and the turbine. Of course, there are other regulating elements. The pump wheel and turbine are connected by a shaft, that is, the rotor. The exhaust gas from the engine drives the pump wheel. The pump wheel drives the turbine to rotate. After the turbine runs, it pressurizes the intake system.

The supercharger is installed on the exhaust side of the engine, so the working temperature of the supercharger is very high, and the rotor speed of the supercharger is very high, which can reach more than 100000 revolutions per minute. Such high speed and temperature make the mechanical needle or ball bearing often encountered unable to work for the rotor. Therefore, the turbocharger generally uses full floating bearing, which is lubricated by engine oil and cooled by antifreeze.

In the past, turbochargers were mostly used in diesel engines. Due to the different combustion modes of gasoline and diesel, the forms of turbochargers used in engines are also different.

The gasoline engine is different from the diesel engine. It is not the air that enters the cylinder, but the mixture of gasoline and air. It is easy to deflagrate when the pressure is too high. Therefore, the installation of turbochargers must prevent deflagration. There are two related questions, one is high temperature regulation, the other is ignition time regulation.

3. Classification

If a car needs to run fast, it must have strong power. At present, the power system of automobile can be roughly divided into natural intake system and supercharged intake system. In European sports cars, except BMW, which still insists on using the naturally aspirated engine, other car companies have used the supercharging system in order to improve the power performance of the car. In recent years, Japanese cars have also widely used turbocharging technology.

The natural intake system is not equipped with any type of supercharger, but only uses the negative pressure caused by the downward piston to suck in the mixture. Although the natural intake system can obtain a larger horsepower output through the variable valve timing system, the power improvement is very limited. In order to effectively increase the output power of the engine, the supercharging system is the most effective way. The most commonly encountered engine turbocharging systems include mechanical turbocharging and exhaust gas turbocharging.