Design Space Analysis for a HALEU NTP Architecture using a Coupled Neutronic Framework

Nuclear thermal propulsion (NTP) has been recognized as a crucial technology for enabling human missions to Mars, owing to its high thrust and efficiency. Currently, several programs are focused on developing a demonstration NTP reactor for flight in cis-lunar orbit. NTP reactors are inherently complex, highly coupled, and constrained systems. Conducting design space analyses or global sensitivity analyses on such systems using traditional high-fidelity codes demands prohibitive computational resources and time. To address this challenge, reduced-order solution methods and systematic reductions in the design space are necessary. This analysis adopts a reduced-order, multi-physics, mission-driven computational framework to delineate the range of feasible designs and identify optimal configurations for a proposed mission utilizing a high-assay low enriched uranium (HALEU) NTP reactor. The computational work presented here focuses specifically on the integration of Serpent, a Monte Carlo transport code, within the overall computational framework.