Finding a way to fuel the flight

Posted: January 18, 2018 - 6:23pm

OAK RIDGE, Tenn. — The Y-12 National Security Complex successfully has fabricated and delivered to the Nevada National Security Site (NNSS) space-reactor core components for the National Aeronautics and Space Administration’s (NASA’s) Kilopower Reactor Using Stirling Technology (KRUSTY) system. The system recently achieved criticality in a test at NNSS using the highly enriched uranium alloy components produced at Y-12.

The KRUSTY demonstration is co-funded by NASA, the Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) and is a milestone in the creation of a small, safe, reliable nuclear reactor that NASA is considering for spacecraft power and planetary surface power for long-term missions. This experiment also allows NNSA to obtain valuable benchmark nuclear cross-section data for DOE/NNSA’s Nuclear Criticality Safety Program (NCSP).

A 2014 agreement with NASA’s Glenn Research Center in Cleveland, Ohio, called for Y-12 to support the design of a small nuclear-powered reactor for potential use in future space exploration missions. The reactor’s “proof of concept” testing at NNSS will continue through early 2018. The Kilopower concept, a kilowatt-range nuclear reactor using an HEU-Mo metallic fuel core, was a 2013 R&D 100 Award winner.

“Y-12 was to have prototype components ready for testing by the end of 2016,” said Chris Robinson, Senior Technical Consultant, Strategic Program Initiatives. “With the expertise and creative thinking of Y-12 engineers and fabricators, we achieved our deadline, and depleted uranium-molybdenum components were sent to Glenn Research Center for preliminary thermal testing in November 2016. NASA personnel and other team members, including Y-12’s program and project manager (Hollie Longmire and Jim Henkel, respectively), assembled and initiated electrically heated thermal testing of the prototype power system.

“With that milestone, we incorporated applicable test results, fabrication and project lessons learned and were able to cast and machine the HEU-Mo components that were delivered to NNSS in September 2017 for testing that resulted in the reactor subassembly (core, reflector, and shielding) achieving criticality, as predicted, November 16,” Robinson said.
With the validation of the reactor subassembly, Los Alamos National Laboratory and NASA engineers/scientists will now integrate the reactor with the power subassembly and proceed toward the full KRUSTY demonstration during the next several months.

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