Transient Analysis of a Micro-reactor using the DireWolf Code Suite

Roskoff, Nathan; Kucukboyaci, Vefa; Levinsky, Alex; Laboure, Vincent M; Harter, Jackson R; Zabriskie, Adam X; Madeleine Charlot, Lise Cecile

DOE OSTI · 1875119

Transient Analysis of a Micro-reactor using the DireWolf Code Suite

Roskoff, Nathan·Kucukboyaci, Vefa·Levinsky, Alex·Laboure, Vincent M·Harter, Jackson R·Zabriskie, Adam X·Madeleine Charlot, Lise Cecile

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Abstract

Transient analyses of heat pipe micro-reactors are necessary to ensure that hypothetical accident scenarios do not comprise reactor safety. Due to its small size and reliance on heat-pipes for cooling, the micro-reactor design introduced in this paper is a tightly coupled system which requires multi-physics tools to accurately model transient events. Idaho National Laboratory’s DireWolf code suite based on the MOOSE framework is tailor-built to model heat-pipe reactors. This paper demonstrates DireWolf’s ability to simulate the coupled thermal-neutronics transient behavior of a heat-pipe micro-reactor. The transient events presented here include an inadvertent rotation of all control drums simultaneously and a sudden complete ejection of a single control drum. A detailed description of each event is provided along with simulation results, including time dependent power and temperature distributions, and discussion. This is a Westinghouse Electric Company (WEC) led publication.

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21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS 22 GENERAL STUDIES OF NUCLEAR REACTORS Direwolf micro-reactor multi-physics analyses

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Roskoff, Nathan, Kucukboyaci, Vefa, Levinsky, Alex, Laboure, Vincent M, Harter, Jackson R, Zabriskie, Adam X, Madeleine Charlot, Lise Cecile. 2022-05-20. Transient Analysis of a Micro-reactor using the DireWolf Code Suite. https://www.osti.gov/biblio/1875119

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