NASA LogoNTRSNTRS - NASA Technical Reports ServerSearchmore_vertCollectionsAboutNewsHelpLogin Back to ResultsAdvanced Stirling Radioisotope Generator Engineering Unit 2 Anomaly InvestigationThe Advanced Stirling Radioisotope Generator (ASRG) Engineering Unit 2 (EU2) is the highest fidelity electrically heated Stirling radioisotope generator built to date. NASA Glenn Research Center completed the assembly of the ASRG EU2 in September 2014 using hardware from the now cancelled ASRG flight development project. The ASRG EU2 integrated the first pair of Sunpower's Advanced Stirling Convertors (ASC−E3 #1 and #2) in an aluminum generator housing with Lockheed Martin's (LM's) Engineering Development Unit (EDU) 4 controller. After just 179 hr of EU2 generator operation, the first power fluctuation occurred on ASC−E3 #1. The first power fluctuation occurred 175 hr later on ASC−E3 #2. Over time, the power fluctuations became more frequent on both convertors and larger in magnitude. Eventually the EU2 was shut down in January 2015. An anomaly investigation was chartered to determine root cause of the power fluctuations and other anomalous observations. A team with members from Glenn, Sunpower, and LM conducted a thorough investigation of the EU2 anomalies. Findings from the EU2 disassembly identified proximate causes of the anomalous observations. Discussion of the team's assessment of the primary possible failure theories, root cause, and conclusions is provided. Recommendations are made for future Stirling generator development to address the findings from the anomaly investigation. Additional findings from the investigation are also discussed.Document ID20180002070Acquisition SourceGlenn Research CenterDocument TypeTechnical Memorandum (TM)AuthorsLewandowski, Edward J.*(NASA Glenn Research Center Cleveland, OH, United States)*Dobbs, Michael W.*(Vantage Partners, LLC Cleveland, OH, United States)*Oriti, Salvatore M.*(NASA Glenn Research Center Cleveland, OH, United States)*Date AcquiredMarch 23, 2018Publication DateMarch 1, 2018Subject CategoryEngineering (General)Report/Patent NumberE-19302NASA/TM-2018-219400AIAA Paper 2016-4816GRC-E-DAA-TN34733Meeting InformationMeeting: International Energy Conversion Engineering ConferenceLocation: Salt Lake City, UTCountry: United StatesStart Date: July 25, 2016End Date: July 27, 2016Sponsors:American Inst. of Aeronautics and AstronauticsFunding Number(s)WBS: WBS 138494.04.18.01.01.01CONTRACT_GRANT: NNC12BA01BDistribution LimitsPublicCopyrightPublic Use Permitted.KeywordsStirling convertorsAdvanced Stirling Radioisotope GeneratorAdvanced Stirling Radioisotope Generator Engineering Unit 2Available DownloadsNameType20180002070.pdfSTIcloud_downloadcontent_copyvisibilityRelated RecordsThere are no records associated with this record.visibility_offNo Preview Available
 No Fear Act | Freedom of Information Act | Office of the Inspector General | Agency Financial ReportsNASA Web Privacy Policy and Important Notices | NASA Guidelines for Quality of InformationDisclaimers, Copyright, Terms of Use | Accessibility | NASA OCIO | USA.gov | NASA.govContact Us | Site MapSTI LogoNASA Official: JoAnne R. Calhoun Site Curator: STI Compliance and Distribution Services Last Modified: September 12, 2024