Research on steady-state behavior of natural circulation with internally heated fluids of liquid-fueled molten salt reactor

Abstract

Liquid-fueled molten salt reactors (LFMSR) utilize internally heated fuel-salt compounds as the working fluid for the first time and the heat source and heat sink conditions are crucial for the natural circulation phenomena. This paper explored the steady-state behaviors of natural circulation of LFMSR and analyzed the impact of internal heat. By incorporating a heat source term into the liquid phase, the natural circulation governing differential equations were modified and solved using a self-developed Python code. Then, the homogeneously volumetric heat model of LFMSR was compared with the core central heat model of a traditional solid fuel reactor, the LFMSR exhibited a smaller steady-state natural circulation flow reducing the natural circulation thermal effect. Subsequently, an extended RELAP5/SCDAPSIM/MOD4.0 code for LFMSR was applied to verify the self-developed code, and their quantitative steady-state parameters showed a good match, which can be used for more complex system analyses in future works.