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DOE, General Matter team up for new fuel mission at Hanford
The Department of Energy's Office of Environmental Management (EM) on Tuesday announced a partnership with California-based nuclear fuel company General Matter for the potential use of the long-idle Fuels and Materials Examination Facility (FMEF) at the Hanford Site in Washington state.
According to the announcement, the DOE and General Matter have signed a lease to explore the FMEF's potential to be used for advanced nuclear fuel cycle technologies and materials, in part to help satisfy the predicted future requirements of artificial intelligence.
K. D. Lathrop
Nuclear Science and Engineering | Volume 45 | Number 3 | September 1971 | Pages 255-268
Technical Paper | doi.org/10.13182/NSE45-03-255
Articles are hosted by Taylor and Francis Online.
Remedies are considered for the ray effect, a flux distortion producing defect of the discrete ordinates approximation to the transport equation. The partially effective remedies of increasing the number of directions, selecting quadrature sets invariant under discrete rotations, and introducing coupling terms into the representation of the transport divergence operator are considered. Numerical results are presented showing the effectiveness of these remedies in a standard test problem. Remedies that eliminate the ray effect are also considered. We show how to formulate multidimensional discrete ordinate equations equivalent to spherical harmonic equations and relate the order of the equivalent spherical harmonic equations to the degree of precision of the numerical quadrature. We give numerical results for this kind of remedy in three test problems, including one with material discontinuities. We show how the use of orthonormal polynomials permits the formulation of discrete ordinates approximations which have properties “like” those of the highest order spherical harmonic equations consistent with the number of directions in the discrete ordinates approximation. We find that these formulations also eliminate ray effects. We conclude that the partially effective remedy of using more, specially chosen, directions is the most practical remedy for most applications, but that for especially difficult situations or for reference calculations, the defect-eliminating spherical harmonic-like formulations should be available for use.