DNS of MHD Turbulent Flow with Buoyancy

Liquid-metals as coolant material in fusion reactor have a significant role in the design of advanced reactors. The investigation of thermal behavior in the actual facility environment, such as in the case of low Pr number fluid flow, is needed with the buoyancy effect under a magnetic field. In the present study, a direct numerical simulation (DNS) for the low Pr number fluid flow of turbulent heat transfer with buoyancy effect has been carried out under a magnetic field. The values of Hartmann number Ha were 0, 8, 16, 32, 64 and 128, and Prandtl number was 0.06. Grashof number was 4.8 x 10. The turbulent quantities such as the mean temperature, turbulent heat flux, and temperature variant were obtained by DNS. The Reynolds number for channel flow based on friction velocity, viscosity, and channel half width was set to be constant as Reτ =150. A uniform magnetic field was applied in a direction perpendicular to the wall of the channel. On the large Hartmann number, large-scale thermal convection by the effect of buoyancy can not be found at the whole region of the channel even if Grashof number is large, that is, the thermal transport is restricted by the effect of the magnetic field