Activation and afterheat in a fusion power reactor

A series of calculations was performed to analyze the activation of the structure of the Princeton Reference Design D- T Fusion Power Reactor. The relevant isotope transmutation chains were solved numerically for 30 years' operation (3/4 load factor) at 5310 MW(t). Decay heat and activity curves versus time after shutdown were obtained for the reference stainless steel structure and for a vanadium alloy as an alternate. Afterheat appears not to pose a safety hazard because of the large blanket heat capacity; however, the large amount of cobalt-60 produced in the steel (2.82 x 10/sup 7/ curies) may make the ultimate disposal of that material difficult. Although the activation in the vanadium is comparable to that in the steel, the short half-lives of the radioisotopes (less than a year) greatly reduce the disposal problems. (auth