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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.
D. W. Stevens, O. M. Stansfield
Nuclear Science and Engineering | Volume 45 | Number 1 | July 1971 | Pages 73-85
Technical Paper | doi.org/10.13182/NSE71-A20347
Articles are hosted by Taylor and Francis Online.
An analysis has been conducted to determine stresses and displacements near the center of long viscoelastic cylinders. Stresses arise due to thermal expansion and irradiation-induced dimensional changes which are anisotropic in transverse planes (i.e., planes perpendicular to the axis of geometrical symmetry). The explicit solution for stress is made possible by the assumption of a linear creep law. The logic is shown for a mathematical model that accounts for finite displacements. The model is used to predict stresses and displacements in borated-graphite absorbers used in the Peach Bottom high-temperature gas-cooled reactor (HTGR). It is predicted that fracture will not occur in the absorbers. This conclusion is presented with the reservation that there is considerable uncertainty regarding irradiation-induced dimensional changes due to the small amount of available data. However, the assumed values for these parameters are believed to be conservative.