Preliminary Analysis of Flow Distribution in a 100-MWth Molten Salt Fast Reactor Core with Flow-guide Structures using Computational Fluid Dynamics

Abstract

A 100-MWth liquid-fueled molten salt fast reactor based on the chloride salt is being developed in Korea Atomic Energy Research Institute for maritime applications. The proposed reactor design has a vacant reactor internal because it does not need any moderator or fuel assemblies. In such structure, a proper distribution of the flow entering a reactor core is one of the challenging issues in reactor design. In this study, we suggest the flow-guide structures including the inlet flow distributor, the flow distribution plate, and the outlet flow collector. To examine the feasibility of the suggested concepts, the preliminary analysis was performed using the computational fluid dynamics (CFD). From the analysis, it was confirmed that the flow distribution inside the reactor can be effectively controlled by changing the number and the distribution of the holes on the flow distribution plate. Based on this result, the design approach for the flow distribution plate was suggested. In addition, the inlet flow distributor and the outlet flow collector significantly contributed to the overall pressure loss. To reduce the pressure drop, the effect of the diameters of each design and the effect of the number of channels on each design were investigated. The overall pressure drop decreased by about 65 % with the 50% increase of the diameter and the 100% increase of the number of the holes.