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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.
Peter Grimm, Menashe Aboudy, Alex Galperin, Meir Segev
Nuclear Science and Engineering | Volume 122 | Number 3 | March 1996 | Pages 395-406
Technical Paper | doi.org/10.13182/NSE96-A24174
Articles are hosted by Taylor and Francis Online.
Preliminary to implementing a pin power reconstruction scheme in the nodal core calculations of the ELCOS system, the “main stream” methods and elements thereof were tested against fine-mesh calculations of a number of benchmark “small cores” consisting of uranium, controlled uranium, and mixed-oxide assemblies. Overall, the results do not clearly favor one of the methods. However, test details conduce us to prefer the 32-term expansion for corner-point fluxes over their determination by the separability assumption, and the 21-term expansion of the intranodal flux over the 13-term expansion. There is little difference whether the factorization of the pin power distribution into global and form factors is imposed on the group fluxes or on the power. Data transfers and matrix inversions connected with the many-term flux expansions slow down the nodal calculation. This condition may be alleviated in some cases by an approximation leading to fewer matrix inversions.