Speaker
Description
Heat-Pipe cooled Reactors (HPRs), which were originally intended for space applications, are of particular interest for remote/autonomous operations as their designs are simple, compact, and transportable. Historically most HPR designs produce only limited thermal power in the kilowatt range and/or utilize highly enriched fuel. This work investigated how reactor design principles can be used to scale up HPRs to higher nominal powers while using less-enriched fuel and without exceeding material limits. The effective core height, number of fuel assemblies, and heat-pipe parameters were used to constrain the design parameter of the final HPR core. The open-source particle transport code OpenMC was used to determine the average volumetric heat rate of a fuel pin, which was coupled with an iterative finite-difference scheme to determine local temperature distributions in the reactor core. These were used to set new material temperatures in the neutronics model, and the process was repeated until the neutron multiplication factor had converged within a tolerance of 50 pcm. The design was simulated at thermal power levels between 5 and 20 MWth, and peak material temperatures were calculated and compared.