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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.
Han Gyu Joo, Guobing Jiang, Thomas J. Downar
Nuclear Science and Engineering | Volume 130 | Number 1 | September 1998 | Pages 47-59
Technical Paper | doi.org/10.13182/NSE98-A1988
Articles are hosted by Taylor and Francis Online.
The nonlinear analytic nodal method, which is formulated by combining the nonlinear iteration technique and the analytic nodal method (ANM), requires analytic solutions of the two-node problems. When the method is applied to problems that contain near-critical nodes in which there is essentially no net leakage, the two-node ANM solution for such nodes results in highly ill-conditioned matrices and potential numerical instabilities, especially in single precision arithmetic. Two stabilization techniques are introduced to resolve the instability problem by employing alternate basis functions for near-critical nodes. The first uses the exact ANM solution for a critical node, and the second employs the nodal expansion method. Both techniques are shown to perform well; however, the solution accuracy can be mildly sensitive to the criterion used to invoke the stabilized coupling kernel.