Otto cycle

Thermodynamic cycle for spark ignition piston engines

An Otto cycle (named after Nicolaus Otto) is an idealized thermodynamic cycle that describes the functioning of a typical spark ignition piston engine. It is the thermodynamic cycle most commonly found in automobile engines. The Otto cycle is a description of what happens to a gas as it is subjected to changes of pressure, temperature, volume, addition of heat, and removal of heat.

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