Study on microengines: miniaturing stirling engines for actuators

This paper describes the micro Stirling engine, a miniaturized Stirling engine the length, width, or height of whose body measure no more than several centimeters. The steps taken both to establish the design concept and actually to produce a microactuator are discussed. Geometrical scale analysis and computer simulation are used to investigate how the design parameters change when the engine size is reduced. This analysis and simulation enable a micro Stirling engine with an approximately 0.05 cm ³ piston swept volume (equivalent ot the displacement of a gasoline is approximately 10 mW at 10 Hz. Problems of scaling down the engine to a maximum length of several millimeters are discussed.