Application of Fuel Depletion Chain Simplification to Experiment Analysis in the Advanced Test Reactor

Labossière-Hickman, Travis J. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000307423404); Calvin, Olin W. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000195600356)

doi:10.1080/00295639.2026.2642505

DOE OSTI · 3365065

Application of Fuel Depletion Chain Simplification to Experiment Analysis in the Advanced Test Reactor

Labossière-Hickman, Travis J. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000307423404)·Calvin, Olin W. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000195600356)

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Abstract

An irradiation experiment analysis can be informed by high-fidelity reactor engineering depletion results, but this comes at a computational cost. Applying depletion chain simplification to the advanced test reactor driver fuel before performing experiment depletions permits their programmatic parameters to be calculated faster, with a small penalty to accuracy. Here, this work contrasts the results of two irradiation experiments with different neutronic characteristics. Overall, the simplified nuclide library produced using a simple one-group microscopic cross-section library for a pressurized water reactor in the depletion chain simplification process performed comparably in terms of accuracy and runtime to the simplified nuclide library produced using a three-group microscopic cross-section library generated specifically for the advanced test reactor experiments being modeled. This is attributed to the additional nuclides and transmutation pathways preserved in the one-group cross-section library, which has data for 297 nuclides, compared to the three-group cross-section library, which has data for 217 nuclides. This indicates that a cross-section library with more nuclides is better than a cross-section library with fewer nuclides for the depletion chain simplification process, even if the cross-section library with fewer nuclides better represents the flux spectrum of the system being considered.

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Labossière-Hickman, Travis J. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000307423404), Calvin, Olin W. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000195600356). 2026-04-01. Application of Fuel Depletion Chain Simplification to Experiment Analysis in the Advanced Test Reactor. https://doi.org/10.1080/00295639.2026.2642505

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