Heat transfer enhancement in MHD free surface flow by controlling the electromagnetic force with fin structure

A partly insulated fin (PIF) structure has been proposed to mitigate the temperature stratification of flowing-type liquid metal divertors. This study conducted a three-dimensional magnetohydrodynamics (MHD) flow and heat transfer numerical simulation to investigate the influence of the PIF on the velocity and the temperature field inside the film flow. An analytical model simulated a liquid metal film flow of 25 mm thickness under a transverse magnetic field up to 1.0 T. The simulation was conducted with a PIF, a metal fin, and without a fin. The results showed the generation of a high velocity region near the surface and the velocity was 2.68 times higher than the case without a fin due to the MHD effect. In addition, an upward flow was observed in front of the PIF. The contribution of the flow field generated by the fin to the temperature field was confirmed through numerical analysis, and the highest temperature of the liquid metal surface decreased by 0.96% at its maximum. A deformation of the surface due to the fin was estimated using the pressure distribution obtained from the simulation. The result indicated expected deformation is 21.8 μm at the magnetic field of 1.0 T.