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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.
L. L. Briggs, E. E. Lewis
Nuclear Science and Engineering | Volume 75 | Number 1 | July 1980 | Pages 76-87
Technical Paper | doi.org/10.13182/NSE80-A20320
Articles are hosted by Taylor and Francis Online.
A new two-dimensional coarse mesh technique for neutron transport calculations, the constrained finite element method, is formulated and applied to a series of nonuniform lattice problems. Finite elements in space and in angle are applied to the variational form of the even-parity transport equation. Spatial and angular constraints on the finite element trial functions along the intercell boundaries lead to a two-step solution procedure in which a global calculation yields the scalar flux values at coarse mesh nodes located on the intercell boundaries. The flux distributions and reaction rates within each cell are then found in terms of the nodal scalar flux values on the cell boundaries. The method is applied to a series of one-group fixed-source lattice problems, and the results are compared to those obtained from unconstrained finite element reference solutions and/or from response matrix solutions.