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DOE OSTI · 3374728

Updating and Refining BISON TRISO Assessment

Gamble, Kyle A. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000284878077)·Hirschhorn, Jacob Aaron [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000302425902)·Sweet, Ryan Terrence [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000279194623)
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Abstract

Several advanced reactor concepts consider tristructural isotropic (TRISO) fuel in their designs. To support the advanced reactor industry, the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program within the U.S. Department of Energy (DOE) is developing modeling and simulation capabilities within the BISON fuel performance code. Assessment of these capabilities against available experi- mental data, such as the Advanced Gas Reactor (AGR) program, is essential in instilling confidence in the code predictions. Associated uncertainties in model inadequacy, experimental measurements, and manufacturing are also of importance. This report discusses the updating and standardization of the existing assessment suite in BISON for TRISO fuel performance analysis. The cases considered the AGR-1, AGR-2, and AGR-3/4 experimental programs. The report also includes a preliminary investigation into the sources of model inadequacy associated with silver (Ag) release fractions using the AGR-2 Compact 2-1-2 as a case study. The results indicate that uncertainties in the operating temperatures supplied to the model and the form of those temperature conditions (spatially averaged versus spatially resolved) both affect Ag release predictions. This suggests that previously observed model inadequacy can be attributed to both physical models and the operating conditions supplied to them. These findings will be leveraged to guide development of assessment cases for additional experiments and refinement of physical models for behaviors that potentially influence Ag release, such as palladium penetration.

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11 - NUCLEAR FUEL CYCLE AND FUEL MATERIALS11 NUCLEAR FUEL CYCLE AND FUEL MATERIALSAGR-1AGR-2AGR-3/4BISONModel InadequacyTRISO

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Gamble, Kyle A. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000284878077), Hirschhorn, Jacob Aaron [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000302425902), Sweet, Ryan Terrence [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000279194623). 2025-09-30. Updating and Refining BISON TRISO Assessment. https://doi.org/10.2172/3374728

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