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DOE OSTI · 1788175

Secondary-Source Core Reload Modeling with VERA

Gentry, Cole·Collins, Benjamin·Davidson, Eva·Davidson, Gregory·Evans, Thomas·Godfrey, Andrew·Hart, Shane·Ilas, Germina·Johnson, Seth·Kim, Kang Seog·Palmtag, Scott·Pandya, Tara·Royston, Katherine·Wieselquist, William·Wolfram, Gary
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Abstract

The CASL reactor simulation package VERA has been adapted to provide high-fidelity simulation capabilities for modeling source range detector response during subcritical reactor configurations. New features include the activation and shuffling of secondary-source assemblies, use of burned fuel neutron emission data from the ORIGEN depletion solver to the MPACT deterministic neutron transport solver, allowance of user-defined sources in MPACT based on material composition, ability to solve the subcritical source-driven system with neutron multiplication using the MPACT diffusion solver, and transfer of the calculated fission source from MPACT to the continuous-energy Monte Carlo solver Shift for final detector response evaluation using the CADIS methodology for variance reduction. These new capabilities were benchmarked against Watts Bar Unit 1 plant operating data for the first few fuel loading steps and were found to demonstrate excellent agreement with the measured data.

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Gentry, Cole, Collins, Benjamin, Davidson, Eva, Davidson, Gregory, Evans, Thomas, Godfrey, Andrew, Hart, Shane, Ilas, Germina, Johnson, Seth, Kim, Kang Seog, Palmtag, Scott, Pandya, Tara, Royston, Katherine, Wieselquist, William, Wolfram, Gary. 2020-11-12. Secondary-Source Core Reload Modeling with VERA. https://doi.org/10.1080/00295639.2020.1820797

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