NTRS - NASA Technical Reports Server

Back to Results
Recent Stirling Conversion Technology Developments and Operational Measurements at NASA Glenn Research CenterIn support of the Advanced Stirling Radioisotope Generator (ASRG) project and other potential applications, NASA Glenn Research Center (GRC) has initiated convertor technology development efforts in the areas of acoustic emission, electromagnetic field mitigation, thermoacoustic Stirling conversion, and multiple-cylinder alpha arrangements of Stirling machines. The acoustic emission measurement effort was developed as a health monitoring metric for several Stirling convertors undergoing life testing. While accelerometers have been used in the past to monitor dynamic signature, the acoustic sensors were chosen to monitor cycle events, such gas bearing operation. Several electromagnetic interference (EMI) experiments were performed on a pair of Advanced Stirling Convertors (ASC). These tests demonstrated that a simple bucking coil was capable of reducing the alternating current (ac) magnetic field below the ASRG system specification. The thermoacoustic Stirling concept eliminates the displacer typically found in Stirling machines by making use of the pressure oscillations of a traveling acoustic wave. A 100 W-class thermoacoustic Stirling prototype manufactured by Northrop Grumman Space and Technology was received and tested. Another thermoacoustic prototype designed and fabricated by Sunpower, Inc., will be tested in the near future. A four cylinder free piston alpha prototype convertor was received from Sunpower, Inc. and has been tested at GRC. This hardware was used as a proof of concept to validate thermodynamic models and demonstrate stable operation of multiple-cylinder free-piston Stirling conversion. This paper will discuss each of these activities and the results they produced.
Document ID
Document Type
Technical Memorandum (TM)
Oriti, Salvatore M.
(NASA Glenn Research Center Cleveland, OH, United States)
Schifer, Nicholas A.
(NASA Glenn Research Center Cleveland, OH, United States)
Date Acquired
August 25, 2013
Publication Date
August 1, 2010
Subject Category
Spacecraft Propulsion And Power
Report/Patent Number
AIAA Paper 2009-4556
Meeting Information
Seventh International Energy Conversion Engineering Conference (IECEC)(Denver, CO)
Funding Number(s)
WBS: WBS 138494.04.01.01
Distribution Limits
Work of the US Gov. Public Use Permitted.
No Preview Available