Low pressure rotary gas engine - has turbine impellers of dimensions corresponding to mean free molecular path

摘要

The cylindrical chamber contains hydrogen or helium at a pressure of less than 1 mm. of mercury absolute. There are two turbine wheels inside the chamber with blades set at 45 degrees. The radial width of the turbines is approximately equal to the mean free path of the gas molecules at the working pressure. The movement of the molecules sets the two wheels in motion in opposite directions. The rotation is transferred to the outside of the chamber by magnetic couplings so that no seals are needed.