Influence of the Horizontal Magnetic Fields on the Natural Convection of Liquid Metal in a Heated Box

In the nuclear fusion reactor, where the temperature differences and magnetic fields are strong, natural convection of liquid metal shows different flow and heat transfer characteristics. In the present work, three-dimensional (3D) numerical simulations are conducted to study the natural convection in an electrically insulated cavity with imposed horizontal magnetic fields parallel to the main circulation, where two opposite vertical walls are kept at different temperatures and the other four are thermally insulating. We mainly focus on flows and heat transfer with the variation of Hartmann (Ha) number, including the main circulation, second flow, temperature fields and Nusselt number (Nu). Our numerical results confirm that the horizontal magnetic fields suppress the convection and heat transfer.