Neutronics and Thermal-Hydraulics Analysis of a Long Operational Life LMR for Lunar Surface Power

This paper presents the results of iterative neutronics and thermal-hydraulic design optimization of a liquid metal cooled reactor for lunar surface power. The reactor placed below grade on the lunar surface is capable of generating 1.0 MW_th continuously for ~20 years without refueling. It satisfies subcriticality requirement for shutdown, during launch and when submerged in wet sand and flooded with seawater in the unlikely event of a launch abort accident. The 3-D thermal-hydraulic design ensures good flow distribution and cooling of UN fuel pins and adequate mixing in the exit duct.