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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.
R. C. Kern, M. T. Hsu
Nuclear Science and Engineering | Volume 68 | Number 1 | October 1978 | Pages 141-143
Technical Note | doi.org/10.13182/NSE78-A27282
Articles are hosted by Taylor and Francis Online.
One difficulty in using the RELAP4 code is that, owing to the overspecification of the volume and junction input data for the initial conditions, a residual friction term must be defined to establish steady-state conditions. If the corresponding residual friction coefficient is out of allowable range, the calculation is terminated at the initial data checking phase. An allowable residual friction coefficient is added to the form loss coefficient and is used throughout the transient calculation. This might affect the results if the residual friction coefficient is large. However, to model a system represented by a large number of volumes and junctions, manual adjustment of the input data, such as the pressure distribution, to reduce the effect of residual terms can take a significant amount of engineering time. A procedure that allows the code to do the adjustment internally is described in this Note.