Internal Combustion Engine

An internal-combustion engine is a heat engine that burns fuel and air inside a combustion chamber located within the engine proper. Simply stated, a heat engine is an engine that converts heat energy to mechanical energy. The internal- combustion engine should be distinguished from the external- combustion engine, for example, the steam engine and the Stirling engine, which burns fuel outside the prime mover, that is, the device that actually produces mechanical motion. Both basic …

…An internal-combustion engine must also have some kind of transmission system to control and direct the mechanical energy where it is needed; for example, in an automobile the energy must be directed to the driving wheels. Since these engines are not able to start under a load, a transmission system must be used to 'disengage' the engine from the load during starting and then to apply the load when the engine reaches its operating speed.