A new cooling concept of free surface flow balanced with surface tension for FFHR

A new cooling concept of free surface flow is proposed as an alternative candidate for the first wall of self-cooling molten-salt Flibe blanket in a helical-type fusion reactor force-free-like helical fusion reactor. Numerical analyses on a capillary flow show that the free surface balanced between surface tension and the forces of wall shear stress and gravity is feasible even in helical systems, where a spiral flow is formed and drastically enhances the heat transfer from the coolant channel wall.