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The deadline arrives: Checking in on the Reactor Pilot Program
On May 23, 2025, President Trump signed Executive Order 14301, “Reforming Nuclear Reactor Testing at the DOE,” which instructed the Department of Energy to create a Reactor Pilot Program (RPP)—a new system in which companies could pursue DOE authorization to build and test their first-of-a-kind nuclear technologies. EO 14301 set an ambitious goal for that program: three reactors achieving criticality by July 4, 2026.
G. Palmiotti, C. B. Carrico, E. E. Lewis
Nuclear Science and Engineering | Volume 115 | Number 3 | November 1993 | Pages 233-243
Technical Paper | doi.org/10.13182/NSE92-110
Articles are hosted by Taylor and Francis Online.
The variational nodal method is generalized to treat within-group and group-to-group anisotropic scattering in two- and three-dimensional eigenvalue and fixed source problems. The resulting formalism is implemented as the VARIational Anisotropic Nodal Transport code (VARIANT) within the shell of the Argonne National Laboratory production code DIF3D. The code is applied to a series of Cartesian and hexagonal geometry model problems and the accuracy of the results compared to those from TWODANT and TWOHEX and to the Monte Carlo code VIM, respectively, in two and three dimensions. VARIANT is then applied to multigroup hexagonal representations of the Experimental Breeder Reactor II, and results are obtained for three-dimensional eigenvalue and for two-dimensional neutron-gamma heating problems.