Figure 1: Concept of a Leidenfrost heat engine.
(a) A heat engine operates between two reservoirs held at temperatures Th and Tc, where Th>Tc. The engine converts part of the heat absorbed, Qin, into work, W. The remaining energy, Qout, is dissipated to the surroundings. (b) A Leidenfrost engine uses a hot turbine whose temperature, Th, is held above the Leidenfrost point of a disc of dry ice. The excess pressure sustains the levitation of the disc. The released vapour is rectified by the underlying turbine, driving the rotation of the disc and generates mechanical work.
