Cylindrical breeding blankets for fusion reactors

Abstract Blankets with a cylindrical structure have been developed for a water-cooled ceramic breeder concept considering a pipe break inside the blanket container. Most existing studies have examined a box structure for the blanket container. Structural change from a box to a cylinder can decrease in first wall thickness while maintaining the pressure resistance of the container. Two blankets with radial and toroidal/poloidal cylindrical axes have been developed. Their first walls are hemispherical and half cylindrical. The tritium breeding capabilities of the developed blankets were studied using Monte Carlo code MCNP5.14. Different combinations of breeder and neutron multiplier materials were considered. With the combination of lithium oxide and beryllium, the tritium breeding ratio of the blankets including surrounding gaps was evaluated as higher than 1.20, leading to a net tritium breeding ratio higher than 1.05.