Study On Heat And Mass Transfer Of Liquid Metal Flow Under High Temperature And Magnetic Field In Fusion Reactor

The liquid metal blanket is one of the main candidate blankets for DEMO.The MHD effect will occur in the flowing liquid metal under the high temperature and strong magnetic field environment of fusion reactor.The MHD effect not only increases the pressure drop in the blanket,but also changes the flow and heat transfer distribution of liquid metals,affecting the transport of tritium.On the basis of fully investigating the MHD numerical simulation program for liquid metal in fusion reactor,the numerical simulation program for MHD flow and heat transfer of liquid metal is further developed and verified by the benchmarks.The MHD numerical simulation program use the potential method to solve the MHD governing equations.Based on the numerical solution of momentum equation,the induced current generated in the flow process is calculated according to Faraday’s law,and the potential distribution in the flow field is calculated according to Poisson’s equation.Then the current density in the flow field is calculated by Ohm’s law,and the Lorentz force at the next moment is incorporated into the MHD control equations for iterative solution.OpenMP parallel programming standard is used for parallel ac-celeration in the running process of numerical simulation program,which improves the running speed of the program.The MHD numerical simulation program developed in this paper has passed the verification of IAEA standard examples,which provides a powerful analysis and research tool for the design optimization of liquid metal blanket.After obtaining the flow field distribution in liquid metal blanket by MHD numer-ical simulation program,the energy conservation equation is solved by finite volume method.The convection term in the equation is discretized by QUICK scheme,and the influence of boundary is transmitted to the internal grid by block correction technology,which speeds up the convergence of numerical calculation process.From the numer-ical results,it can be seen that the shear flow significantly improves the heat transfer capacity of liquid metal near the side wall.The MHD numerical simulation program couples momentum equation with energy equation,and calculates the MHD flow and heat transfer distribution in the blanket under the influence of temperature.The calculation results show that the flow velocity of liquid metal near the side wall will slow down,and the heat transfer capacity of conductive fluid will be weakened,resulting in the case that the temperature of liquid metal near the side wall is higher than that of the viscous coefficient unchanged.The results of numerical simulation further deepen the understanding of the flow and heat transfer in the actual working conditions of fusion reactor,which is of great significance to the design optimization of the fusion reactor blanket.The experimental system of high pressure helium/liquid lithium-lead MHD heat transfer loop is designed in this paper.It can not only carry out heat transfer experiments of liquid lithium-lead,but also verify the results of MHD numerical simulation program.After analyzing the process of tritium transport in liquid metal blanket,the mass transfer equation in the process of tritium transport is given.And the tritium transport process in liquid metal blanket is numerically simulated,which provides a reference for studying the mechanism of tritium transport in liquid lithium-lead blanket in high magnetic field of fusion reactor.