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DOE OSTI · 2205011

INL Report: Multiphysics Modeling and Simulation of Deimos, an Advanced Reactor Experiment

Maldonado, Alexis·Trellue, Holly Renee·Cutler, Theresa Elizabeth·Stolte, Kristin Nichole
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Abstract

When designing a novel reactor, nuclear experiments are essential to validate the predictive capability of modeling/simulation tools and to justify the investment of a full-scale prototype. Being able to accurately predict temperature reactivity coefficients is of high importance to reactor designers as it impacts the safety and performance of the system. Deimos is a proposed graphite-moderated, beryllium-reflected, high assay low-enriched uranium (HALEU) tri-structural isotropic (TRISO) fueled experiment for NCERC. Deimos is a valuable experiment for validating the predictive performance of modeling and simulation tools since it comprises a relatively thermal energy spectrum with 84% thermal neutrons causing fission, 15% epithermal neutrons causing fission, and 1% fast neutrons causing fission. Additionally, by electrically heating the experiment, reactivity can be validated at various temperatures. Deimos will serve as a testbed for future advanced reactor concepts.

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Maldonado, Alexis, Trellue, Holly Renee, Cutler, Theresa Elizabeth, Stolte, Kristin Nichole. 2023-11-01. INL Report: Multiphysics Modeling and Simulation of Deimos, an Advanced Reactor Experiment. https://doi.org/10.2172/2205011

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