Conversion of thermal energy e.g. piston engine exhaust gases into kinetic energy includes accelerating a gas at temperature and pressure values exceeding those of the ambient air through a jet and mixing with colder ambient air

In the process, cold atmospheric air is introduced via an injection tube into the centre of a flow tube containing flowing hot gases from e.g. a piston engine. By mixing in or admixing of the cold atmospheric air with the hot gases, the static air pressure in or after the jet in the flow tube attains the same speed as that of the hot gases, the temperature falls and the mass is raised. The kinetic energy of gases is raised due to the increased mass of the accelerated gas caused by cooling of the gas in the flow tube. The speed of the gas stream is unaffected by the incoming cold air. Technisches Verfahren zur Wandlung von thermischer in kinetische Energie, insbesondere dadurch gekennzeichnet, daß der Druck in Geschwindigkeit und die Temperatur in Masse gewandelt wird.