Design optimization of a liquid sodium magnetohydrodynamic circulation system for a 20 MWe micro-nuclear reactor

Abstract

This study was presented the design optimization and numerical analysis of a sodium magnetohydrodynamic (MHD) circulation system intended for an all-in-one, liquid-sodium-cooled micro-nuclear reactor. Generally, given the compact size and high heat flux associated with microreactors, a stable and efficient cooling system is essential. MHD-based liquid metal circulation has emerged as a promising solution to this challenge. To determine the optimal MHD system configuration, an equivalent circuit-based fluid flow model was employed in this study. The system was designed to deliver a mass flow rate of 360 kg/s and a pressure head of 73 kPa at an operating temperature of 250 degrees C. The input power required for circulation was calculated to be 597 kW, which corresponds to approximately 3 % of the reactor's total electrical output of 20 MWe. These results demonstrate that the optimized design variables can enable the realization of a practical and energy-efficient MHD-based sodium cooling system with minimized input power and reduced energy losses, thereby supporting the broader implementation of micro-nuclear reactor technologies.