Major improvements in the WCLL TBM design towards next review gates

Abstract

The European domestic agency (Fusion for Energy) is developing the WCLL-TBS (Water Cooled Lithium Lead Test Blanket System) concept for its implementation and testing in ITER. The system is based on the use of the eutectic Pb–15.7Li enriched at 90 % in 6Li as tritium breeder and tritium carrier. Water is used as coolant with current target nominal inlet/outlet temperatures of 295/328 °C and 15.5 MPa pressure (similar to PWR conditions). The Test Blanket Module –TBM– is the in-vessel component where tritium generation will take place and whose structural material is EUROFER 97. Its design has been significantly improved in the last years. These design improvements have focused on three major areas: (i) overcoming some weaknesses of the previous design in the rear manifold area associated to the stiffening rod concept, (ii) strengthening the link with manufacturing developments and (iii) optimizing the amount of EUROFER 97 in the TBM box, so that the design converges to the limits imposed by the ITER project requirements. The work presented in this paper describes the latest design evolutions achieved in the WCLL TBM design with respect to that presented at CDR and, in particular, the major re-design of the TBM in the manifold area based on the ‘crossing vertical’ stiffening plate concept proposed and developed by the ESTEYCO Mechanics design team in collaboration with F4E.