Neutronics performance of high-temperature refractory alloy helium-cooled blankets for fusion application

Among the concepts considered in the advanced power extraction (APEX) study is the helium-cooled refractory metal FW and blanket concept. Refractory metals exhibit high operating temperature and can offer good capability for withstanding high power density operation that is the focus of the APEX study. In this paper, we assess the impact of using various refractory metals on the nuclear heating profiles across the blanket and power multiplication (PM) and on the tritium breeding profiles and tritium breeding ratio (TBR). The refractory metals considered with liquid lithium breeder are W, TZM, and Nb–1Zr. The impact of Li-6 enrichment on these profiles and on TBR and PM is also assessed. Comparison of these nuclear characteristics is also made to other liquid breeder (Flibe and Li–Sn). Because the moderation power of these breeders to neutron energy varies among them, the damage to the structure is different with various structure/breeder combinations. The damage parameters (DPA, helium and hydrogen production) at key locations are also compared with the corresponding values in the thick liquid FW/blanket concept; an innovative design concept under consideration within the APEX study.