RAMI comparison of two China test blanket modules

Tritium breeding blanket module is one of the most important parts of fusion reactor. One of the main goals of ITER is to test and validate design concepts of tritium breeding blankets. China has proposed two test blanket module (TBM) concepts, including Helium cooled ceramic breeder test blanket module system (HCCB TBS) and the dual functional lithium-lead test blanket module system (DFLL TBS), which will be tested in one of the three equatorial ports of ITER. A detailed comparative study on the design schemes of these two TBSs concepts was performed in this paper. In this study, the RAMI (Reliability, Availability, Maintainability, Inspectability) approach was applied on those two test blanket systems. The modeling and analyzing process were done by the Reliability and Probabilistic Safety Assessment Software System RiskA. In addition, comparative study in the phases of functions, capabilities and efficiencies of tritium breeding, heat removal and coolant purification is also performed. It is found that HCCB TBS is a better choice currently to fulfill the engineering demand of ITER construction for its lower difficulty of technical implementation. However, DFLL TBS possesses a high performance prospect from the viewpoint of long-term ITER development due to its inherent advantages compared to HCCB TBS. Discussions of priorities for future research needed for these two TBS are also proposed in the paper.