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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.
B. Akherraz, C. Fedon-Magnaud, J. J. Lautard, R. Sanchez
Nuclear Science and Engineering | Volume 120 | Number 3 | July 1995 | Pages 187-198
Technical Paper | doi.org/10.13182/NSE95-A24118
Articles are hosted by Taylor and Francis Online.
Three approaches are presented to treat anisotropic scattering in neutron transport. The approaches are based on the even-odd-parity flux formalism and yield three different second-order equations for the even-parity flux. The first one is based on the total elimination of the odd-parity flux of the second-order equation. In the other two approaches, anisotropic scattering contributions are homogenized and incorporated into the collision term. The numerical solutions of these equations are implemented in the CRONOS code for pressurized water reactor core calculations and are done with a finite element spatial approximation and the discrete ordinates methods (SN) for the angular variable. Numerical results are presented for critical problems (keff) in x-y geometry. Comparisons with the APOLL02 assembly code show the accuracy and the efficiency of the proposed algorithms.