Thermofluid analysis of free surface liquid divertor in tokamak fusion reactor

Abstract

To attain high fusion power density, the divertor must suffer a high heat flux from the fusion plasma. It is very difficult to remove the high heat flux from the fusion plasma more than 20 MW/m 2 using the only solid divertor plate due to the severe mechanical condition such as thermal stress and crack growth. Therefore, the concept of a liquid divertor is proposed to remove the high heat flux and neutron flux from the plasma by liquid films flowing on a solid wall. Feasibility study on the liquid divertor is being examined what kind of necessary condition should be satisfied if it was applied to the tokamak fusion reactor. There are many uncertain physics and techniques to apply the liquid divertor to the tokamak fusion reactor. This paper mainly descries a preliminary thermofluid analysis of a free surface liquid, made of FLiBe molten salt, flow suffering the high heat flux using the finite element analysis code ADINA-F. To realize the liquid divertor, two techniques of thermal hydraulics promotion using a secondary flow and liquid-solid multi-phase flow are proposed in this paper.