Simplification of blanket system for SlimCS fusion DEMO reactor

Abstract Simplification of blanket system is necessary for a fusion DEMO reactor. Although the conceptual design of a tritium-breeding blanket for SlimCS has been studied in the past several years, the structure of the previous blanket seems to be complex and difficult to manufacture from the viewpoint of engineering. In this paper, we proposed simplification of blanket structure without decreasing the net Tritium Breeding Ratio (TBR). In the proposed concept, the blanket is filled with the mixture of Li 4 SiO 4 pebbles or Li 2 O pebbles for the tritium breeding and Be 12 Ti pebbles for the neutron multiplication. To confirm the effectiveness of this concept, an ANIHEAT code with the nuclear library FENDL-2.0 was used for calculations of the neutronic and thermal analyses. The result indicated that, under the constraint of the blanket thickness being less than 0.5 m, the mixture of Li 2 O pebbles and Be 12 Ti ones is the most effective and that the TBR is expected to be greater than 1.05.