Nuclear features of the fusion ignition research experiment (FIRE)

The main nuclear features of the baseline design of fusion ignition research experiment (FIRE) have been evaluated. Critical issues were addressed and R&D needs were identified. Modest values of nuclear heating occur in the FIRE components. The total nuclear heating in the 16 TF coils during DT shots is 19 MW. The cumulative damage in the copper alloys used is very low (<0.05 dpa). However, issues of low temperature embrittlement and thermal creep at high temperatures need to be resolved by an R&D program. The radiation induced resistivity increase in the conductors of the TF coils is primarily due to displacement damage and is <20% of the unirradiated resistivity. The magnet insulator development R&D program should involve irradiation to dose levels up to 1.5×1010 Rad with the proper mix between neutrons and gamma photons (50% gamma dose) relevant to FIRE conditions. Low levels of activity and decay heat are obtained. Hands-on ex-vessel maintenance is feasible. All components qualify as Class C low-level waste. Activation of nitrogen gas inside the cryostat produces a very small amount of 13N and 14C.