Conceptual study on liquid metal center conductor post in spherical tokamak reactors

A novel concept of liquid metal centre conductor post is proposed for spherical tokamak reactors. Flowing liquid metal Li inside the replaceable tube made of low activation materials (alloy, stainless steel etc.) coated by SiC is used as the medium carrying toroidal field coil current and removing Ohmic heat and nuclear heat in the center conductor post. The calculation and analysis have shown that the novel concept has potentially attractive advantages mainly including less transmutation wastes, no electric conductivity change, tolerable neutron structure damage, enhancement in tritium breeding ratio and longer service time in comparison with the conventional concept based on copper alloy conductor. The possible engineering and technological problems are specified for further study.