Micro-scale molten salt & metal reactor for space applications

Abstract

In this thesis, the Molten Salt Metal Reactor (MSMR) designed for space applications is introduced. Utilizing a uranium alloy liquid metal as fuel, this reactor incorporates the advantages of Molten Salt Reactors (MSRs) while achieving criticality in a compact size and enabling a long operational lifespan without the need for refueling. To adapt the existing MSMR for space use, high-assay low-enriched uranium (HALEU) and heat pipes were employed, and comprehensive optimizations were conducted to realize a compact reactor that encompasses both high output and longevity. Compared to other space reactors, the MSMR offers significant advantages in terms of lifespan and structural simplicity. Additionally, factors contributing to the reactor's safety, such as shutdown margin and reactivity coefficient, were evaluated. For neutronics and shielding analysis, the Monte Carlo code Serpent 2 was used, and the integrity of materials under a 300kWth condition was assessed using the finite element method-based computational fluid dynamics code COMSOL 6.1 for thermal-hydraulics analysis.