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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
Nuclear Science and Engineering | Volume 21 | Number 1 | January 1965 | Pages 79-89
Technical Paper | doi.org/10.13182/NSE65-A21017
Articles are hosted by Taylor and Francis Online.
An analytical study has been made of the general problem of heat-transfer to liquid metals flowing between parallel plates. All the results are for the conditions of uniform heat fluxes and fully-established temperature and velocity profiles. Both unilateral and bilateral heat-transfer situations have been considered. In the former, three different methods of determining the velocity profiles were compared; and for each of these, three different types of profile curves for the eddy diffusivity of momentum, ∈M, were compared. The three different methods of determining the velocity profiles showed remarkably good agreement. In the case of bilateral heat transfer, the fraction of total heat transfer to the fluid from any one plate, ξ, was varied from zero to unity. It was found that the heat-transfer coefficient for any one plate is a sensitive function of ξ for that plate. Above ξ = 0.31, the coefficients are positive; below it, they are negative. At ξ = 0.31, the coefficient is infinite, because at this condition the difference between wall and bulk temperatures is zero. As ξ approaches 0.50, from either above or below, the shape of the εM profile in the vicinity of the center of the channel has less and less effect on the heat-transfer coefficient. When ξ = 0.50, the effect is negligible for all practical purposes. There are no adequate experimental data available with which to test the calculated Nusselt numbers, but indications are that the recommended relationships are reasonably correct.