Neutronics Analysis for HYLIFE-II

A preliminary neutronics analysis of the HYLIFE-II reactor concept gives a tritium breeding ratio of 1.17 and a system energy multiplication factor of 1.14. Modified SS-316 (in which Mn is substituted for Ni) is superior to Hastelloy X and Hastelloy N as a first-wall material considering He generation, dpa-limited lifetime, and shallow-burial index. Since Flibe is corrosive to Mn metals, however, a favorable first-wall material is yet to be decided on. Flibe impurities considered (e.g., inherent impurities and those arising from wall erosion or secondary-coolant leakage) do not increase the hazard to the public over that of pure Flibe. The main issues for HYLIFE-II are the high shallow-burial index (106) and the requirement to contain some 99.7% of the ¹⁸F inventory to prevent its release to the public.