Technology Development for a Stirling Radioisotope Power System for Deep Space Missions

Abstract NASA Glenn Research Center and the Department ofEnergy (DOE) are developing a Stirling convertor for anadvanced radioisotope power system to provide spacecrafton-board electric power for NASA deep space missions.NASA Glenn is addressing key technology issues throughthe use of two NASA Phase II SBIRs with Stirling Tech-nology Company (STC) of Kennewick, WA. Under thefirst SBIR, STC demonstrated a 40 to 50 fold reduction invibrations, compared to an unbalanced convertor, with asynchronous connection of two thermodynamically inde-pendent free-piston Stirling convertors. The second SBIRis for the development of an Adaptive Vibration Reduc-tion System (AVRS) that will essentially eliminate vibra-tions over a mission lifetime, even in the unlikely eventof a failed convertor. This paper discusses the status andresults for these two SBIR projects and also presents re-suits for characterizing the friction factor of high-porosityrandom fiber regenerators that are being used for thisapplication.