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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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DOE-NE’s newest fuel consortium includes defense from antitrust laws
The Department of Energy's Office of Nuclear Energy is setting up a nuclear fuel Defense Production Act Consortium that will seek voluntary agreements with interested companies “to increase fuel availability, provide more access to reliable power, and end America’s reliance on foreign sources of enriched uranium and critical materials needed to power the nation’s nuclear renaissance.” According to an August 22 DOE press release, the plan invokes the Defense Production Act (DPA) to give consortium members “defense from antitrust laws when certain criteria are met” and “allow industry consultation to develop plans of action.” DOE-NE is looking for interested companies to join the consortium ahead of its first meeting, scheduled for October 14.
L. M. Gomes, P. N. Stevens
Fusion Science and Technology | Volume 19 | Number 3 | May 1991 | Pages 1996-2000
Neutronic | Proceedings of the Ninth Topical Meeting on the Technology of Fusion Energy (Oak Brook, Illinois, October 7-11, 1990) | doi.org/10.13182/FST91-A29634
Articles are hosted by Taylor and Francis Online.
This work revisits the problem of ray effects in discrete ordinates calculations that frequently occurs in two- and three-dimensional systems which contain isolated sources within a highly absorbing medium. The effectiveness of using a first collision source or a second collision source are analyzed as possible remedies to mitigate this problem. The first and second scattering sources are calculated with the Monte Carlo method that is intrinsically free from ray effects. The scattering source is then coupled to a discrete ordinates code for a hopefully ray-effect-free transport calculation. The scattering source generated by the Monte Carlo method is distributed throughout geometry space and therefore would be less likely to produce ray effects in the discrete ordinates calculation. This remedy for the ray effect is demonstrated for a point source in cylindrical geometry and for a localized distributed source in X-Y geometry. The first collision and second collision sources are generated by three-dimensional Monte Carlo calculations and enables its application to a variety of source configurations and the results can be coupled to a two- or three-dimensional discrete ordinates transport code. The Monte Carlo computational time and precision requirements constitute some limitations but these are minimized since the Monte Carlo transport is performed only up to the first collision.