Thermofluid analysis of free surface liquid divertor in tokamak fusion reactor

Kurihara, Ryoichi

To attain high fusion power density, the divertor must suffer high heat flux from the fusion plasma. It is very difficult to remove a high heat flux more than 20 MW/m using the only solid divertor plate from the viewpoint of severe mechanical state such as thermal stress and crack growth. Therefore, a concept of liquid divertor is proposed to remove high heat flux by liquid films flowing on a solid wall. This paper mainly descries a preliminary thermofluid analysis of the free surface liquid flow, made of the FliBe molten salt, using the finite element analysis code ADINA-F. The heat flux of 25100 MW/m was given on the free surface liquid of the flow. I explored a possibility of applying the secondary flow to enhance the heat transfer of the liquid flow suffering high heat flux. This analysis shows that the heat flux of 100 MW/m can be removed by inducing the secondary flow in the free surface liquid FLiBe. And this paper shows that the liquid divertor using solid-liquid multi-phase flow makes possible large heat removal by utilizing the latent heat of fusion of solid phase.