noun
heat engine; thermomotor
Technical term in physics and engineering for a device that converts thermal energy into mechanical work.
蒸気機関は代表的な熱機関の一つです。
The steam engine is one of the typical heat engines.
熱機関の効率は熱力学の法則によって制限される。
The efficiency of a heat engine is limited by the laws of thermodynamics.
外燃機関 is another subtype of heat engine where combustion occurs externally, contrasting with 内燃機関.
Compound of 熱 (netsu, 'heat') and 機関 (kikan, 'engine, mechanism'). A straightforward technical term.