Seminar: Stirling-based Power Systems

Abstract:

The Stirling cycle has the potential for high conversion efficiency of thermal energy to mechanical or electrical energy with a wide range of fuels, temperature ratios, and power levels. NASA has been investigating the closed-cycle free-piston Stirling engine-generator (“Stirling convertor”) for space applications. For deep space missions where photovoltaic power is not practical, power from radioisotope or fission sources is typically required. Stirling-based thermal to electrical energy conversion technology offers several benefits for space power systems. This talk will provide background on the Stirling engine and explain the workings of the free-piston Stirling convertor. Recent progress on designing, fabricating, and testing Stirling radioisotope generators will be discussed. Phasor diagrams will be used to explain some of the principles of free-piston Stirling convertor operation and analysis. Exciting research challenges in the field of Stirling-based power systems will be reviewed.

About the Speaker:

Dr. Ed Lewandowski is a researcher at NASA Glenn Research Center in Cleveland, Ohio, working on Stirling-based space power systems. He got is his Ph.D. in Mechanical Engineering from the University of Wisconsin in 1990, where he conducted research in control of hybrid hydraulic vehicle powertrains. He worked for 11 years at Cummins Engine Co, developing advanced fuel systems and on-board monitoring and diagnostic systems for diesel engines. From 2000 to 2003 he worked for a joint venture between GE and the Lubrizol Corporation in Cleveland trying to commercialize on-board oil monitoring systems with remote monitoring and diagnostics for large diesel engines. Since 2003 he has been at NASA Glenn Research Center, where he has supported Stirling systems testing, simulation, and analysis since 2003. Dr. Lewandowski has five patents and numerous publications and is a member of AIAA and ASME.

Hosted by Professor Mike Benzakein