Assessing the behaviour of solid particulates in the flow of molten salt reactor coolant circuits

Abstract

This work investigated solid particulate behaviour in molten salt nuclear reactors. Solid particulates are expected to form from fission products reacting with fuel components, creating compounds with melting temperatures above the reactor operational temperature. These particulates may present operational risks including flow obstruction and corrosion. A sensitivity analysis was performed by simulating flow of molten salt within a reactor containing solid particulates via Computational Fluid Dynamics, where three parameters of the particulate were varied: diameter, density, and initial concentration. A case was simulated where values for these properties were selected based on a review of related literature. Subsequently, two more simulations were performed for each parameter using high and low values within the expected ranges, modifying only one parameter at a time. Results indicate that particle diameter has low impact on fluid dynamics of the reactor, but particulate density and concentration resulted in increased localized accumulation and cyclical movement of the particulate at the reactor outer edges.