external combustion engine
The external combustion engine, that is to say its fuel is burned outside the engine, was invented by R. Sterling of Scotland in 1816, so it is also called the Stirling engine. The engine converts the heat energy generated by this combustion into kinetic energy. The steam-modified steam engine is a typical external combustion engine. When a large amount of coal is burned to generate heat to heat the water into a large amount of water vapor, high pressure is generated. The high pressure pushes the mechanical work, thus completing the transformation of thermal energy into kinetic energy.
internal combustion engine
Understand what is an external combustion engine, and know what an internal combustion engine is. The biggest difference between this type of engine and the external combustion engine is that its fuel burns inside. There are many types of internal combustion engines, and common gasoline engines and diesel engines are typical internal combustion engines. Unusual rocket engines and jet engines assembled on aircraft are also internal combustion engines. However, due to the different power output methods, there are huge differences between the first two and the latter two. In general, most of the use on the ground is the former, and the latter is mostly used in the air. Of course, some automakers have used jet engines for the purpose of creating a new record for the world's car speeds, but this is always a very special case and there is no applicability for mass production.
In addition, there is a gas turbine, which is characterized in that combustion produces high-pressure gas, and the high pressure of the gas is used to drive the blades of the gas turbine to rotate, thereby outputting power. Gas turbines are used in a wide range of applications, but because it is difficult to fine-tune the output power, gas turbines are rarely used in cars and motorcycles, and only some cars are equipped with gas turbines.