Performance of the TAURO blanket system associated with a liquid-metal cooled divertor

Abstract

Blankets and divertors are the key components of a fusion power plant due to their large impact on the overall plant design, performance and availability, and on the cost of electricity. This paper recalls the main features of the TAURO blanket, a self-cooled Pb–17Li concept using SiC f/SiC composite as structural material, and describes the most recent thermo-mechanical analyses performed on the blanket. It includes an evaluation of a liquid-metal cooled divertor which could be associated with such a blanket. Investigations were carried out to determine the potential and limits of the blanket and of a liquid-metal cooled divertor in terms of maximum acceptable surface heat flux. The high outlet temperature of the Pb–17Li coolant (800°C) leads to an attractive energy conversion efficiency (>47%) assuming helium-coolant for the secondary circuit. Special heat exchangers, using SiC f/SiC tubes are envisaged. Thermo-mechanical analyses have pointed out that maximum surface heat flux on FW and divertor could be about 0.65 and <5 MW/m 2, respectively. It is expected that an improvement of the SiC f/SiC modeling, taking into account non linear behavior presently under way, and the use of design criteria adapted to more advanced composites could allow even higher limits.