An external combustion engine is unique from other EHEs because it requires a fuel to undergo combustion to create the heat that is used for work. External combustion engines are no longer used in transportation, as mobile designs are not efficient enough, but they continue to be used in power plants.

How can you define external combustion engine?

An external combustion engine is a heat engine where an (internal) working fluid is heated by combustion of an external source, through the engine wall or a heat exchanger. The fluid then, by expanding and acting on the mechanism of the engine produces motion and usable work.

Which engine is known as external combustion engine?

An external combustion engine (EC engine) is a heat engine where a working fluid, contained internally, is heated by combustion in an external source, through the engine wall or a heat exchanger. The fluid then, by expanding and acting on the mechanism of the engine, produces motion and usable work.