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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.
W. E. Abbott, E. J. Allen
Nuclear Science and Engineering | Volume 108 | Number 3 | July 1991 | Pages 278-288
Technical Note | doi.org/10.13182/NSE91-A23825
Articles are hosted by Taylor and Francis Online.
Two new difference schemes are derived for numerically solving the transport equation in spherical geometry. The first difference method is positive; i.e., the calculated fluxes are never negative. Furthermore, for the first method, the error expansion is suitable for applying Richardson extrapolation with respect to both spatial and angular variables to increase the accuracy of the approximate fluxes. Numerical experiments illustrate the accuracy obtained using this procedure, as well as demonstrate that the accuracy of the second difference method is significantly improved through application of Richardson extrapolation. In addition, the numerical results indicate that the second method is significantly more accurate than the standard nonextrapolated diamond-difference method for numerically solving the transport equation in spherical geometry.