Pistemoottori

Pistemoottori, also known as a reciprocating engine or piston engine, is a type of internal combustion engine that uses the back-and-forth motion of a piston within a cylinder to convert chemical energy into mechanical energy. This mechanical energy is then typically used to drive a crankshaft, which in turn can power vehicles, machinery, or generators. The fundamental operation involves a cycle of events within the cylinder: intake, compression, power, and exhaust.

During the intake stroke, a mixture of fuel and air is drawn into the cylinder as the piston moves downwards. The compression stroke follows, where the piston moves upwards, squeezing the fuel-air mixture. This compression increases the temperature and pressure, preparing it for ignition. The power stroke occurs when a spark plug ignites the compressed mixture, causing a rapid expansion of gases that forces the piston downwards. Finally, during the exhaust stroke, the piston moves upwards again, pushing the burnt gases out of the cylinder.

Pistemoottorit can be classified based on several factors, including the number of strokes in their cycle (two-stroke or four-stroke), the type of fuel they use (gasoline, diesel, natural gas), and their configuration (inline, V-engine, boxer engine). Four-stroke engines are more common in automotive applications due to their better fuel efficiency and lower emissions compared to two-stroke engines, which are often found in smaller, simpler applications like chainsaws or older motorcycles. The widespread use of pistemoottorit stems from their relative simplicity, reliability, and adaptability to various power requirements.