Abstract
A SCALE model was developed for the Molten Salt Reactor Experiment (MSRE) benchmark that was recently added to the International Handbook of Evaluated Reactor Physics Benchmark Experiments. This SCALE model served as a basis for criticality calculations and nuclear data sensitivity and uncertainty analyses with the Monte Carlo code Shift and the TSUNAMI computational capabilities in the SCALE code system. The focus of this work is the assessment of the impact of nuclear data on the calculated eigenvalue results in support of the discussion of differences between the calculated and the experimental eigenvalue result. The differences in the eigenvalues obtained using the ENDF/B-VII.0, ENDF/B-VII.1, and ENDF/B-VIII.0 nuclear data libraries cover a relatively small range of (Formula presented.) 230 pcm. Since eigenvalue sensitivity of the MSRE is dominated by the neutron multiplicity and neutron capture of 235U and elastic scattering in graphite, relevant changes in the ENDF/B libraries for nuclear reactions (such as carbon capture) that caused large differences in other graphite-moderated systems did not have a significant impact. Propagation of nuclear data uncertainty results in an eigenvalue uncertainty of (Formula presented.) pcm with the major contributors being (Formula presented.) U neutron multiplicity, graphite elastic scattering, and 7Li neutron capture. All calculations resulted in large differences of (Formula presented.) 2000 pcm in eigenvalue compared to the benchmark experimental value. Several potential contributors to this difference—including uncertainties and gaps in the knowledge of the material, geometry, and nuclear data—were identified. Simplified models of the full MSRE core were developed, and similarity assessments were conduced with the full MSRE core model. It was found that simplified models can serve as adequate surrogates of the full-core model such that they can be used for performing selected nuclear data performance assessments with a lower computational burden.
Original language | English |
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Pages (from-to) | 603-624 |
Number of pages | 22 |
Journal | Nuclear Technology |
Volume | 208 |
Issue number | 4 |
DOIs | |
State | Published - 2022 |
Funding
This work was funded by the U.S. Nuclear Regulatory Commission. The continuous technical support received from Don Algama and Tim Drzewiecki is especially appreciated. This paper has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the U.S. Department of Energy. This work was supported by the U.S. Nuclear Regulatory Commission [ IAA 31310019N0009 ]; U.S. Nuclear Regulatory Commission [ IAA 31310019N0008 ]; U.S. Nuclear Regulatory Commission [ IAA 31310019N0012 M0002 ].
Funders | Funder number |
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U.S. Department of Energy | IAA 31310019N0008 |
U.S. Nuclear Regulatory Commission | DE-AC05-00OR22725 |
Keywords
- MSRE
- SCALE
- criticality
- sensitivity analysis
- uncertainty analysis