First of all, if classified according to fuel, engines can be divided into gasoline engines, diesel engines, gas-fuel engines, gas engines, liquefied petroleum gas engines, and multi-fuel engines.

Therefore, the difference in fuel used is also between gasoline engines and diesel engines. The obvious difference. But in addition, the design and some working principles of the two engines themselves are actually quite different.

For example, gasoline engines and diesel engines are also four-stroke engines, and their working cycles are mainly based on the Alto cycle-intake, compression, workmanship, and exhaust.

But because diesel has a greater viscosity than gasoline, and its auto-ignition temperature is lower than gasoline. Coupled with the intake phase, gasoline engines inhale a combustible mixture of air and fuel, while diesel inhales pure air.

Therefore, during the compression stroke, the compression pressure in the cylinder of the gasoline engine at the end of compression should be as small as possible and should not exceed the auto-ignition temperature of the gasoline to avoid causing knocking. spark plug ignition of gasoline engine

In contrast, diesel engines, the compression pressure in the cylinder should be as large as possible at the end of compression (generally can reach 3-5Mpa). In this way, when the fuel injector injects diesel, there will be enough pressure to "ignite" it.

This is why the compression ratio of gasoline engines is low, generally around 10:1. In contrast, diesel can reach 20:1 or even higher.