Evaluation of nuclear heating, tritium breeding and shielding efficiency of the DEMO HCLL breeder blanket

Three-dimensional radiation transport calculations employing the MCNP Monte Carlo code have been performed to predict the neutronics performance of the Helium Cooled Lithium Lead (HCLL) DEMO-type blanket. The nuclear energy deposition as well as its spatial distribution, both in radial and poloidal directions, in each blanket module have been calculated. The tritium breeding ratio has been assessed considering different 6Li enrichments and radial depths of the breeder zone of the blanket and the cases providing tritium self-sufficiency have been identified. The shielding performance of the blanket has been investigated at the inboard torus mid-plane regarding the radiation load to the super-conducting toroidal field coil. Appropriate shield configurations are proposed to ensure the radiation load is below the design limit.