Heat Engine

Machines that convert heat energy into mechanical work through the expansion of a working fluid, including the steam engine, the steam turbine, the gas turbine and the combined cycle gas turbine that pairs a gas turbine with a heat-recovery steam cycle. Belongs here: any technology whose core mechanism is thermodynamic expansion of a heated fluid against a moving part. Does not belong here: nuclear reactor designs, which supply the heat a steam turbine may then convert but are themselves grouped under Nuclear Reactor; hydropower turbines, which convert the kinetic and potential energy of falling water rather than heat, grouped under Hydropower Turbine.