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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Latest News
Lightbridge to test uranium-zirconium fuel alloy in INL’s ATR
Lightbridge Corporation has fabricated samples of nuclear fuel materials made of an enriched uranium-zirconium alloy, matching the composition of the alloy that the company intends to use for its future commercial Lightbridge Fuel product. The fuel is designed to improve the performance, safety, and proliferation resistance of nuclear reactors, according to the company. The enriched coupon samples will now be placed into capsules for irradiation testing in Idaho National Laboratory’s Advanced Test Reactor.
F. J. Arias
Nuclear Science and Engineering | Volume 178 | Number 2 | October 2014 | Pages 240-249
Technical Paper | doi.org/10.13182/NSE13-88
Articles are hosted by Taylor and Francis Online.
The phenomenology for a particular behavior of packed beds in heavy liquid metal (HLM) fast reactors during postaccident heat removal is proposed. Because of the similar densities of the fuel and the HLM, an inherent passive safety self-removal feedback mechanism due to buoyancy forces is developed, which propels the packed bed away from the wall, thus preventing temperatures that can jeopardize the vessel’s structural integrity and also reducing the recriticality potential by limiting the allowable bed depth. This identified mechanism will have somewhat compensatory tendencies in the self-leveling behavior of debris beds, which are crucial for sodium-cooled reactors, but unfortunately, it is not operative for HLMs because of the absence of boiling of the coolant. By means of a simplified geometrical model, a preliminary analysis of the potentiality of the phenomenon has been performed.