DEVELOPMENT OF A 1-WATT STIRLING CONVERTOR FOR SMALL RADIOISOTOPE POWER SYSTEMS

摘要

A variety of mission concepts have been studied by-NASA and the U. S. Department of Energy that would utilize low power Radioisotope Power Systems (RPS) for landers, probes, and rovers. These missions would contain science measuring instruments that could be distributed across planetary surfaces or near objects of interest where solar flux is insufficient for using solar cells. The studies proposed use offractional versions of the General Purpose Heat Source (GPHS) or multiple Light Weight Radioisotope Heater Units (LWRHU) to heat power conversion technologies. Dynamic power systems are capable of higher conversion efficiency, which could enable equal power using less fuel or higher power using equal fuel, when compared to less efficient static power conversion technologies. Low power Stirling comertors are being developed at NASA Glenn Research Center (GRC) to provide future micro spacecraft with electrical power by converting heat from one or more LWRHUs. An initial concept, developed for distributed landers, would convert eight Watts of heat to one Watt of electrical power output for science instruments and communication. Providing spacecraft with more power could decrease duty-cycling of basic functions and increase the quality and abundance of science data. Development of the concept includes maturation of convenor and controller designs, performance evaluation of an evacuated metal foil insulation, and exploration of new fabrication methods like additive manufacturing.