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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Latest News
NRC grants Clinton and Dresden license renewals
Three commercial power reactors across two Illinois nuclear power plants—Constellation’s Clinton and Dresden—have had their licenses renewed for 20 more years by the Nuclear Regulatory Commission.
L. R. Cornejo, B. S. Collins, S. G. Stimpson, A. M. Graham
Nuclear Science and Engineering | Volume 195 | Number 8 | August 2021 | Pages 890-905
Technical Paper | doi.org/10.1080/00295639.2021.1877503
Articles are hosted by Taylor and Francis Online.
For full-core modeling in the Virtual Environment for Reactor Analysis (VERA), the three-dimensional multigroup eigenvalue neutron transport problem is solved by MPACT. To improve the efficiency of MPACT, advancements have been made in the transport accelerator. Multilevel-in-energy and multilevel-in-space coarse mesh finite difference (CMFD) solvers were developed to improve the efficiency of the CMFD accelerator. In this paper a new multilevel-in-space-and-energy CMFD solver is developed with coarsening in both space and energy on every level. Several different strategies are investigated for coarsening groups in energy. Modified V-cycle and multiple-cycle algorithms are evaluated for solving the multilevel equations. The performance of these solvers is compared for typical full-core reactor physics problems.