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Education and training to support Canadian nuclear workforce development
Along with several other nations, Canada has committed to net-zero emissions by 2050. Part of this plan is tripling nuclear generating capacity. As of 2025, the country has four operating nuclear generating stations with a total of 17 reactors, 16 of which are in the province of Ontario. The Independent Electricity System Operator has recommended that an additional 17,800 MWe of nuclear power be added to Ontario’s grid.
Bin Zhang, Liang Zhang, Cong Liu, Yixue Chen
Nuclear Science and Engineering | Volume 189 | Number 2 | February 2018 | Pages 120-134
Technical Paper | doi.org/10.1080/00295639.2017.1394085
Articles are hosted by Taylor and Francis Online.
Angular discretization errors inherent in the discrete ordinates method are a major problem, especially for localized source problems and problems with strongly absorbing media or large-volume void regions, where angular discretization errors would be totally unacceptable. This paper proposes a regional angular adaptive algorithm together with a goal-oriented error estimate to solve the SN equations. Standard angular adaptive refinement techniques are based on estimated local errors. We compare an interpolated angular flux value against a calculated value to generate local errors. The adaptive quadrature sets can be created by subdividing a spherical quadrilateral into four spherical subquadrilaterals that have positive weights and can be locally refined. Techniques for mapping angular fluxes from one quadrature set to another are developed to transfer angular fluxes on the interfaces of different spatial regions. To provide a better detector response, local errors are weighted by the importance of a given angular region toward the computational goal, providing an appropriate goal-oriented angular adaptivity. First collision source methods are employed to improve adjoint flux calculation accuracy. We tested the performance and accuracy of the proposed goal-oriented regional angular adaptive algorithm within the ARES code for a number of benchmark problems and present the results of a one-region test model and the Kobayashi benchmark problems. The reduction of angular number is at least one order of magnitude for adaptive refinement. The benchmarks demonstrate that the proposed goal-oriented adaptive refinement can achieve the same level of accuracy as the SN method, which has significantly higher computation cost. Thus, adaptive refinement is a viable approach for investigating difficult particle radiation transport problems.