DIN 4340 E : 1976

A gas turbine is a heat engine supplied with rotating components, which converts thermal power into mechanical power. It consists of one or more compressors, devices for the heating or cooling of the operating fluids *), one or more turbines, control devices and all the necessary equipment enabling the delivery of the mechanical power in usable form. Its operating fluid passed through a continuous cycle in the gaseous state, being first of all compressed, then heated and finally expanded again with simultaneous delivery of mechanical power. The operating fluid is compressible, and is used in a manner which prevents it from condensing, i.e. a so-called perfect gas.