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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.
O. E. Dwyer, P. S. Tu
Nuclear Science and Engineering | Volume 21 | Number 1 | January 1965 | Pages 90-105
Technical Paper | doi.org/10.13182/NSE65-A21018
Articles are hosted by Taylor and Francis Online.
The results of an analytical study of bilateral heat transfer to liquid metals flowing turbulently through annuli are reported. The study was based on the assumptions of 1) uniform, though not necessarily equal, heat fluxes from the walls, 2) fully-established temperature and velocity profiles, and 3) no effect of transverse temperature variations on the physical properties of the liquid metal. The fraction, ξ, of the total heat delivered to the flowing stream which comes from the inner wall was varied from zero to unity. Also two special situations were treated: (A) equal heat fluxes from both walls, and (B) uniform but unequal heat fluxes at the walls, with equal wall temperatures at a given axial position along the channel. The results are presented in the form of Nusselt numbers for r2/r1 values from 1 to 7, Peclet numbers for 102 to 104, and ξ values from 0 to 1. The coefficient for the heat transferred from the inner wall goes to infinity at a certain value of ξ, which depends only on the ratio r2/r1. The same thing occurs for the coefficient for the outer walls, except at a different values of ξ. The interesting observation was made that at Pe = 6700, the Nusselt numbers for the following situations are all equal to about 35: 1) flow in a pipe, 2) flow between parallel plates with equal heat fluxes from both plates, 3) flow in any annulus with equal heat fluxes from the walls, with reference to the heat transferred from the outer wall, 4) flow in any annulus with a uniform heat flux from each wall and having equal wall temperatures at a given axial position, with reference to the heat transferred from the outer wall.