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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.
C. K. Sanathanan, J. C. Carter, F. Miraldi
Nuclear Science and Engineering | Volume 23 | Number 2 | October 1965 | Pages 130-137
Technical Paper | doi.org/10.13182/NSE65-A28137
Articles are hosted by Taylor and Francis Online.
In Part I of this series, the authors have developed mathematical techniques to investigate the dynamics of coolant circulation in boiling-water nuclear reactors. This paper is an attempt to apply those techniques to various specific situations. A natural-circulation loop with a single heated channel is considered first. Dependence of the degree of stability upon the steady-state profile of the channel heat flux and the channel length are investigated. The influence of the pressure drops in the downcomer and at the channel inlet upon the transient two-phase flow is studied. The steady-state perturbations in the void fraction and velocity due to a small perturbation in the channel heat flux are predicted. The findings of the present study compare favorably with those obtained by the simplifying assumption made by the earlier investigators that the slip ratio is a constant along the channel length. The more interesting system with two or more channels operating in parallel with a common downcomer is considered next. The strength of the coupling between the dynamics of the flows through the channels increases with the pressure drop in the common downcomer, and this phenomenon is considered quantitatively. Results obtained theoretically are substantiated by comparison with those obtained through elaborate numerical methods and previous observations.