Puristusmoottorit

Puristusmoottorit, commonly known as internal combustion engines, are a type of engine where the combustion of fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the fluid circuit of the engine. The expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine, such as a piston, turbine blade, or nozzle. This force moves the component over a distance, converting chemical energy into useful mechanical energy.

The vast majority of modern internal combustion engines are internal combustion piston engines. These engines operate through a cycle of intake, compression, power, and exhaust strokes. During the intake stroke, a mixture of fuel and air enters the cylinder. This mixture is then compressed by a piston. In spark-ignition engines (like those in most gasoline cars), a spark plug ignites the compressed fuel-air mixture, causing a rapid expansion of gases that pushes the piston down during the power stroke. In compression-ignition engines (like those in diesel vehicles), the fuel is injected into highly compressed, hot air, causing it to ignite spontaneously. The piston then returns to the top of the cylinder, expelling the exhaust gases.

Internal combustion engines are widely used in transportation, including cars, trucks, motorcycles, and aircraft. They are also found in many industrial applications, such as generators, pumps, and lawnmowers. Despite their widespread use, internal combustion engines are known for their emissions, which contribute to air pollution and climate change. Research and development efforts are ongoing to improve their efficiency and reduce their environmental impact, as well as to develop alternative power sources.