Exploratory tritium breeding performance study on a water cooled lead ceramic breeder blanket for EU DEMO using Serpent-2

Innovative Water cooled Lead Ceramic Breeder (WLCB) blanket concepts are being developed at Karlsruhe Institute of Technology (KIT) to explore alternative options for the European demonstration fusion power plant (DEMO). Compared to the Helium Cooled Pebble Bed blanket (HCPB, which is one of the two driver blanket concepts of the European DEMO), Lead/ Lead-alloy is used as neutron multiplier instead of Be/Be-alloy and pressurized subcooled water is used as coolant instead of Helium in the WLCB. The tritium self-sufficiency is the vital function that a Breeding Blanket has to achieve. The absorption of neutrons by water leads to a decrease in the number of neutrons, so the requirement to improve the tritium breeding capacity of the water-cooled blankets is particularly prominent. The Monte Carlo neutron transport code Serpent-2 developed by VTT in Finland has already been benchmarked to be applicable to neutronics calculations in the fusion reactors in a previous study. In this paper, an exploratory TBR study on Water cooled Lead Ceramic Breeder Blanket is presented.