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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
E. E. Lewis
Nuclear Science and Engineering | Volume 102 | Number 2 | June 1989 | Pages 140-152
Technical Paper | doi.org/10.13182/NSE89-A23639
Articles are hosted by Taylor and Francis Online.
Variational nodal methods for neutron transport are modified to reduce the angular coupling between spatial nodes without a commensurate loss of accuracy. In both one and two dimensions, the interface conditions of the variational principle allow near Pn accuracy to be obtained with only Pn−2 interface coupling. As a result, the dimension of the nodal response matrix is reduced by a factor of 2, and the number of arithmetic operations required for solution by a factor of 4. In the small spatial mesh limit, the resulting Pn, n−2 approximation retains accuracy near the Pn approximation used within the node rather than reverting to the Pn−2 interface approximation. Two-dimensional P3,1 transport calculations demonstrate that the variational nodal approximations are not subject to the flux depression suffered by other interface current nodal transport methods in problems dominated by streaming diagonal to the coordinate directions.