Final Results for the GRC Supporting Technology Development Project for the 110-Watt Stirling Radioisotope Generator (SRG110)

Schreiber, Jeffrey G.; Thieme, Lanny G.

doi:10.1063/1.2437471

Cited by 13 publications

(5 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…13 through 16 continues. This was previously described in Schreiber and Thieme (2007). While these convertors are somewhat different in configuration from those…”

Section: Extended Operation Of Tdc'smentioning

confidence: 99%

See 1 more Smart Citation

GRC Supporting Technology for NASA's Advanced Stirling Radioisotope Generator (ASRG)

Schreiber

Thieme²

2008

AIP Conference Proceedings

Self Cite

View full text Add to dashboard Cite

“…13 through 16 continues. This was previously described in Schreiber and Thieme (2007). While these convertors are somewhat different in configuration from those…”

Section: Extended Operation Of Tdc'smentioning

confidence: 99%

“…The GRC supporting technology effort that addressed issues for the SRG110 has been widely reported (Schreiber, 2006;Schreiber and Thieme, 2007). The primary purpose of the effort was to reduce risk and enhance reliability wherever possible for the long-life generator.…”

Section: Grc Supporting Technology Development For the Asrgmentioning

confidence: 99%

GRC Supporting Technology for NASA's Advanced Stirling Radioisotope Generator (ASRG)

Schreiber

Thieme²

2008

AIP Conference Proceedings

Self Cite

View full text Add to dashboard Cite

“…The SRG-110, a 110-We RPS design with dynamic conversion had reached the engineering unit stage before redirection of the project in 2006 (Ref. 14). The SRG-110 design integrated two free-piston Stirling convertors with flexure-bearing technology.…”

Section: American Superconductor (Amsc) Flexure Isotope Stirling Convmentioning

confidence: 99%

Dynamic Power Convertor Development for Radioisotope Power Systems at NASA Glenn Research Center

Oriti

Wilson

2018

2018 International Energy Conversion Engineering Conference

View full text Add to dashboard Cite

The Thermal Energy Conversion Branch at NASA Glenn Research Center is supporting the development of high-efficiency power convertors for use in radioisotope power systems (RPS). Significant progress was made toward such a system that utilized Stirling conversion during the 2001 to 2015 timeframe. Flight development of the Advanced Stirling Radioisotope Generator (ASRG) was canceled in 2013 by the U.S. Department of Energy (DOE) and NASA Headquarters primarily due to budget constraints, and the Advanced Stirling Convertor (ASC) technology contract was subsequently concluded in 2015. A new chapter of technology development has recently been initiated by the NASA RPS Program. This effort is considering all dynamic power convertor options, such as Stirling and Brayton cycles. Four convertor development contracts supporting this effort were awarded in 2017. The awarded contracts include two free-piston Stirling, one thermoacoustic Stirling, and one turbo-Brayton design. The technology development contracts each consist of up to three phases: design, fabrication, and test. As of May 2018, all contracts have completed the design phase, and each underwent a design review with an independent review board. Three of the contracts are planned to execute the phase 2 option for fabrication. Convertors manifesting from these development efforts will then undergo independent validation and verification (IV and V) at NASA facilities, which will consist of convertor performance and RPS viability demonstrations. Example tests include launch vibration simulation, performance mapping over the environmental temperature range, and static acceleration exposure. In parallel with this renewed development effort, Glenn is still demonstrating free-piston Stirling convertor technology using assets from previous projects. The Stirling Research Laboratory (SRL) is still operating several convertors from previous development projects, which have similarities and relevance to current contract designs. Four of these are flexure-bearing based and another six are gas bearing based. One of the flexure-bearing convertors has accumulated over 110,000 h of operation and holds the current record for maintenance-free heat-engine run time. Another flexure-bearing convertor was recently manually shut down after 105,620 h of operation, then disassembled and inspected. This inspection produced a wealth of information about the effects of this amount of run time on the technology's components. One of the engineering unit flexure-bearing convertors recently underwent a launch simulation vibration test, a static acceleration exposure up to 20 g, and was then placed on extended operation. Among the gas-bearing convertors, the longest running unit has accumulated over 70,000 h of operation. Four high-fidelity gas-bearing convertors from the ASRG project are still operating continuously for which the longest run time has reached 28,000 h.

show abstract

“…Prior to the ASC, NASA and DOE were developing the SRG-110 which used Technology Demonstration Converters (TDC) built by Infinia Corporation [7]. These units use internal flexure bearings, rather than the hydrostatic gas bearings used in ASCs.…”

Section: Figure 3 Asc-e3mentioning

confidence: 99%

Stirling to flight initiative

Hibbard

Mason

Ndu

et al. 2016

2016 IEEE Aerospace Conference

View full text Add to dashboard Cite

NASA has a consistent need for radioisotope power systems (RPS) to enable robotic scientific missions for planetary exploration that has been present for over four decades and will continue into the foreseeable future, as documented in the most recent Planetary Science Decadal Study Report. As RPS have evolved throughout the years, there has also grown a desire for more efficient power systems, allowing NASA to serve as good stewards of the limited plutonium-238 ( 238 Pu), while also supporting the ever-present need to minimize mass and potential impacts to the desired science measurements. In fact, the recent Nuclear Power Assessment Study (NPAS) released in April 2015 resulted in several key conclusion regarding RPS, including affirmation that RPS will be necessary well into the 2030s (at least) and that 238 Pu is indeed a precious resource requiring efficient utilization and preservation. Stirling Radioisotope Generators (SRGs) combine a Stirling cycle engine powered by a radioisotope heater unit into a single generator system. Stirling engine technology has been under development at NASA Glenn Research Center (GRC) in partnership with the Department of Energy (DOE) since the 1970's. The most recent design, the 238 Pu-fueled Advanced Stirling Radioisotope Generator (ASRG), was offered as part of the NASA Discovery 2010 Announcement of Opportunity (AO). The Step-2 selections for this AO included two ASRGenabled concepts, the Titan Mare Explorer (TiME) and the Comet Hopper (CHopper), although the only non-nuclear concept, InSight, was ultimately chosen. The DOE's ASRG contract was terminated in 2013. Given that SRGs utilize significantly less 238 Pu than traditional Radioisotope Thermoelectric Generators (RTGs) -approximately one quarter of the nuclear fuel, to produce similar electrical power output -they provide a technology worthy of consideration for meeting the aforementioned NASA objectives. NASA's RPS Program Office has recently investigated a new Stirling to Flight (S2F) initiative with the objective of developing a 100-500 W e Stirling generator system. Additionally, a different approach is being devised for this initiative to avoid pitfalls of the past, and apply lessons learned from the recent ASRG experience. Two key aspects of this initiative are a Stirling System Technology Maturation Effort, and a Surrogate Mission Team (SMT) intended to provide clear mission pull and requirements context. The S2F project seeks to lead directly into a DOE flight system development of a new SRG. This paper will detail the proposed S2F initiative, and provide specifics on the key efforts designed to pave a forward path for bringing Stirling technology to flight.

show abstract

Final Results for the GRC Supporting Technology Development Project for the 110-Watt Stirling Radioisotope Generator (SRG110)

Cited by 13 publications

References 17 publications

GRC Supporting Technology for NASA's Advanced Stirling Radioisotope Generator (ASRG)

GRC Supporting Technology for NASA's Advanced Stirling Radioisotope Generator (ASRG)

Dynamic Power Convertor Development for Radioisotope Power Systems at NASA Glenn Research Center

Stirling to flight initiative

Contact Info

Product

Resources

About