Abstract
The MPACT neutronics module of the Virtual Environment for Reactor Analysis (VERA) has used the subgroup method for resonance self-shielding calculation, for which two-dimensional (2D) fixed-source transport calculations are performed using method of characteristics for resonance energy groups. When considering thermal feedbacks, the subgroup calculation must be performed at each outer iteration. Therefore, the computing time for cross section processing is a significant burden for computational efficiency. The Dancoff-based Wigner-Seitz approximation (DWA) capability has been implemented into MPACT in conjunction with the subgroup method, which has been used in SCALE/XSProc since SCALE version 6.0 and has recently been called an equivalent Dancoff-factor cell (EDC) method. The issue of relatively large reactivity bias in DWA for the gadolinia rods was resolved by introducing multiple Dancoff factors. Benchmark results for the VERA pressurized and boiling water reactor benchmark suites show that the DWA capability would significantly enhance computational efficiency with comparable accuracy.
| Original language | English |
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| Title of host publication | Proceedings of the International Conference on Physics of Reactors, PHYSOR 2022 |
| Publisher | American Nuclear Society |
| Pages | 2134-2143 |
| Number of pages | 10 |
| ISBN (Electronic) | 9780894487873 |
| DOIs | |
| State | Published - 2022 |
| Event | 2022 International Conference on Physics of Reactors, PHYSOR 2022 - Pittsburgh, United States Duration: May 15 2022 → May 20 2022 |
Publication series
| Name | Proceedings of the International Conference on Physics of Reactors, PHYSOR 2022 |
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Conference
| Conference | 2022 International Conference on Physics of Reactors, PHYSOR 2022 |
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| Country/Territory | United States |
| City | Pittsburgh |
| Period | 05/15/22 → 05/20/22 |
Funding
This research was supported by the US Department of Energy, the Nuclear Energy Advanced Modeling and Simulation Program. Notice: This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan).
Keywords
- Dancoff factor
- Wigner-Seitz approximation
- resonance self-shielding
- subgroup