Core flow distribution design of molten salt reactor with liquid fuel

Abstract Background: In the thermal-hydraulic design of molten salt reactor(MSR) with liquid fuel, the structure and the flow field distribution of lower plenum play a decisive role for the core flow distribution. Purpose: The mass flow distribution of core inlet is designed to match with the release heat distribution, so that the core power distribution will be flattened in radical. Methods: To realize the reasonable distribution of core flow, the flow field of lower plenum is optimized through adjusting the geometry of core lower plenum and flow distribution device using FLUENT software to simulate three-dimensional flow field of core. Results: The simulation results showed that the mass flow rate standard deviation of salt channels of trumpet-shape lower plenum is reduced by 4.2% compared with that of the ellipsoid-shape. The mass flow rate standard deviation of salt channel is reduced by 29.2% by setting the flow distribution plate. Conclusion: Changing the structure of lower plenum and setting the flow distribution plate are useful measures to adjust the mass flow distribution and power matching. The results can provide the basis for the optimization design of MSR with liquid fuel. (authors)