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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.
Edward W. Larsen
Nuclear Science and Engineering | Volume 83 | Number 1 | January 1983 | Pages 90-99
Technical Paper | doi.org/10.13182/NSE83-A17992
Articles are hosted by Taylor and Francis Online.
A parameter ∊ is introduced into the discrete ordinates equations in such a way that as ∊ tends to zero, the solution of these equations tends to the solution of the standard diffusion equation. The behavior of spatial differencing schemes for the discrete ordinates equations is then studied, for fixed spatial and angular meshes, in the limit as ∊ tends to zero. We show that numerical solutions obtained by the diamond difference, linear characteristic, linear discontinuous, linear moments, exponential, and Alcouffe schemes all converge, in this limit, to the correct transport or diffusion result, while numerical solutions obtained by the weighted-diamond and Takeuchi schemes do not converge to the correct limiting result.