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DOE OSTI · 3029254

Griffin Capability Improvements in Support of Ex-core Deep-Penetration Problems

Choi, Namjae [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000315866272)·Hanophy, Joshua Thomas [Idaho National Laboratory (INL), Idaho Falls, ID (United States)]·Wang, Yaqi [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000237373498)·Ortensi, Javier [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000316853916)·Chase, Benjamin M. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)]
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Abstract

Advanced reactor designs, especially portable reactors that are designed to be located closer to humans and operate autonomously, require the ability to accurately compute the ex-core neutron and gamma flux solutions in terms of shielding design optimization to reduce dose rates at the vessel boundary and detector signal prediction to drive the reactor control system. The Nuclear Energy Advanced Modeling and Simulation program has prioritized improvements to the Griffin discrete ordinates (SN) solver for deep-penetration problems in fiscal year 2025. Significant advancements have been made to the Griffin methodologies for solving ex-core deep-penetration problems for steady-state, fixed-source and transient calculations. This work presents the methodology improvements as well as a comprehensive demonstration with a Transient Test Reactor model and measurements.

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Choi, Namjae [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000315866272), Hanophy, Joshua Thomas [Idaho National Laboratory (INL), Idaho Falls, ID (United States)], Wang, Yaqi [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000237373498), Ortensi, Javier [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000316853916), Chase, Benjamin M. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)]. 2025-06-30. Griffin Capability Improvements in Support of Ex-core Deep-Penetration Problems. https://doi.org/10.2172/3029254

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