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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.
M. Mordant
Nuclear Science and Engineering | Volume 92 | Number 2 | February 1986 | Pages 218-227
Technical Paper | doi.org/10.13182/NSE86-A18169
Articles are hosted by Taylor and Francis Online.
A type of “phase-space discontinuous diamond” difference scheme, or “phase-space linear discontinuous finite element” approximation, is implemented to solve the two-dimensional [(x-y) or (r-z)] neutron transport equation. The results obtained on some well-known transport benchmark problems are much more accurate than discrete ordinates solutions attained with spatial diamond differencing or discontinuous finite element approximations. Error studies show convergence to the phase-space fine-mesh limit solution with an approximate and convergence rate, at least in the case of rectangular cells on phase-space domain D × V. In addition, phase-space fine-mesh limit results have been estimated with the help of extrapolation procedures for some neutron transport benchmark problems. This phase-space linear discontinuous finite element approach can be easily enlarged to more general spaces.