Simple benchmark for evaluating self-shielding models
Accounting for self-shielding effects is paramount to accurate generation of multigroup cross sections for use in deterministic reactor physics neutronics calculations. Historically, equivalence in dilution and subgroup techniques have been the preeminent means of accounting for these effects, but r...
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| Format: | Article |
| Language: | en_US |
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American Nuclear Society
2017
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| Online Access: | http://hdl.handle.net/1721.1/108003 https://orcid.org/0000-0001-7717-0364 https://orcid.org/0000-0003-2497-4312 https://orcid.org/0000-0003-1459-7672 |
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| author | Gibson, Nathan Andrew Smith, Kord S. Forget, Benoit Robert Yves |
| author2 | Massachusetts Institute of Technology. Department of Nuclear Science and Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Nuclear Science and Engineering Gibson, Nathan Andrew Smith, Kord S. Forget, Benoit Robert Yves |
| author_sort | Gibson, Nathan Andrew |
| collection | MIT |
| description | Accounting for self-shielding effects is paramount to accurate generation of multigroup cross sections for use in deterministic reactor physics neutronics calculations. Historically, equivalence in dilution and subgroup techniques have been the preeminent means of accounting for these effects, but recent work has proposed new solutions, including the Embedded Self-Shielding Method (ESSM). This paper presents a very simple benchmark problem to compare these and future self-shielding methods. The benchmark is perhaps the simplest problem in which both energy and spatial self-shielding effects are important, a two-region problem with a lumped resonant material. A single resonance in a
single energy group is considered. Scattering is approximated using the narrow resonance approximation, decoupling each energy value and allowing an easily-computed reference solution to be obtained.
Equivalence in dilution using two-term rational expansions and the subgroup method were both found to give very accurate solutions on this benchmark, with errors less than 1% in nearly all cases. One-term rational expansions and ESSM showed much larger errors. |
| first_indexed | 2024-09-23T15:57:34Z |
| format | Article |
| id | mit-1721.1/108003 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T15:57:34Z |
| publishDate | 2017 |
| publisher | American Nuclear Society |
| record_format | dspace |
| spelling | mit-1721.1/1080032022-10-02T05:21:58Z Simple benchmark for evaluating self-shielding models Gibson, Nathan Andrew Smith, Kord S. Forget, Benoit Robert Yves Massachusetts Institute of Technology. Department of Nuclear Science and Engineering Gibson, Nathan Andrew Smith, Kord S. Forget, Benoit Robert Yves Accounting for self-shielding effects is paramount to accurate generation of multigroup cross sections for use in deterministic reactor physics neutronics calculations. Historically, equivalence in dilution and subgroup techniques have been the preeminent means of accounting for these effects, but recent work has proposed new solutions, including the Embedded Self-Shielding Method (ESSM). This paper presents a very simple benchmark problem to compare these and future self-shielding methods. The benchmark is perhaps the simplest problem in which both energy and spatial self-shielding effects are important, a two-region problem with a lumped resonant material. A single resonance in a single energy group is considered. Scattering is approximated using the narrow resonance approximation, decoupling each energy value and allowing an easily-computed reference solution to be obtained. Equivalence in dilution using two-term rational expansions and the subgroup method were both found to give very accurate solutions on this benchmark, with errors less than 1% in nearly all cases. One-term rational expansions and ESSM showed much larger errors. 2017-04-10T14:43:26Z 2017-04-10T14:43:26Z 2015-04 Article http://purl.org/eprint/type/ConferencePaper 9781510808041 http://hdl.handle.net/1721.1/108003 Gibson, Nathan A., Kord Smith, and Benoit Forget. "Simple Benchmark for Evaluating Self-Shielding Models." Proceedings of Mathematics and Computations, Supercomputing in Nuclear Applications and Monte Carlo International Conference (M&C+SNA+MC 2015), Nashville, Tennessee, USA. Vol. 1. pp. 1832-851. https://orcid.org/0000-0001-7717-0364 https://orcid.org/0000-0003-2497-4312 https://orcid.org/0000-0003-1459-7672 en_US http://www.proceedings.com/27010.html Proceedings of the Mathematics and Computations, Supercomputing in Nuclear Applications and Monte Carlo International Conference, 2015. (M&C+SNA+MC 2015) Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf American Nuclear Society Prof. Forget via Chris Sherratt |
| spellingShingle | Gibson, Nathan Andrew Smith, Kord S. Forget, Benoit Robert Yves Simple benchmark for evaluating self-shielding models |
| title | Simple benchmark for evaluating self-shielding models |
| title_full | Simple benchmark for evaluating self-shielding models |
| title_fullStr | Simple benchmark for evaluating self-shielding models |
| title_full_unstemmed | Simple benchmark for evaluating self-shielding models |
| title_short | Simple benchmark for evaluating self-shielding models |
| title_sort | simple benchmark for evaluating self shielding models |
| url | http://hdl.handle.net/1721.1/108003 https://orcid.org/0000-0001-7717-0364 https://orcid.org/0000-0003-2497-4312 https://orcid.org/0000-0003-1459-7672 |
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