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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.
Hui Zhang, E. E. Lewis
Nuclear Science and Engineering | Volume 142 | Number 1 | September 2002 | Pages 57-63
Technical Note | doi.org/10.13182/NSE02-A2287
Articles are hosted by Taylor and Francis Online.
A spatial adaptive grid method is presented for the solution of two-dimensional neutron transport problems employing the spherical harmonics method within the framework of the variational nodal method. The work represents the generalization of an approach previously applied to the neutron diffusion equation. After reviewing pertinent aspects of the derivation of the variational nodal response matrices, an a posteriori estimator of the local error in the scalar flux is developed. An iterative adaptive procedure is then presented, and application is made to two-dimensional problems. Results are presented for a P5 solution of the well-known Iron-Water Benchmark Problem.