A new modular design concept for China's HCSB TBM in ITER

Previous designs from China (CN) for a helium-cooled solid breeder (HCSB) breeder blanket (BB) require modifications to increase the tritium breeding ratio (TBR) so that the design will satisfy tritium self-sufficiency requirements for a power-producing fusion reactor (DEMO) while ensuring engineering feasibility. A modified design for a CN HCSB test blanket module (TBM) is given in which thick enclosure walls around the breeding units are removed, the mass of cooling plate structural material is reduced, and the ratio (by volume) of Be zones to Li4SiO4 zones is optimized. Analysis of the proposed design is performed by using Monte Carlo neutron transport code. The TBR of the proposed design is 1.18, which is greater than the 1.15 ratio required for tritium self-sufficiency, and 39.15% higher than the previous design's TBR of 0.848. Based on new 3D neutronics results for a DEMO reactor, a preliminary 2 x 6 HCSB TBM design concept is suggested.