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Atlanta, GA|Atlanta Marriott Marquis
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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
E. Varin, G. Samba
Nuclear Science and Engineering | Volume 151 | Number 2 | October 2005 | Pages 167-183
Technical Paper | doi.org/10.13182/NSE05-A2538
Articles are hosted by Taylor and Francis Online.
To mitigate some drawbacks of the discrete ordinates method or the even-parity approach, a new deterministic method for solving the Boltzmann transport equation is proposed. Based on a scaled least-squares formulation, the first-order transport equation is solved for a spherical harmonics expansion of the angular flux. This approach allows a continuous finite element discretization. Discrete equations have been derived for media with anisotropic scattering. Moreover, extensions are proposed to allow for solutions in three-dimensional multiplicative regions. Asymptotic analyses of this least-squares approach show the need for a scaling of the transport equation in order to maintain the diffusion limit. One-dimensional tests are used to evaluate this scaling operator, and results are compared with reference solutions. Anisotropic multigroup scattering cases are also presented. Tests on a three-dimensional simple problem show that ARTEMIS, the transport solver based on this method, gives solutions free of ray effects.