Engineering features of the fusion ignition research experiment (FIRE)

The fusion ignition research experiment (FIRE) tokamak is an option for the next step in the US magnetic fusion energy program. It has a major radius of 2 m, and a minor radius of 0.525 m. The general requirements for FIRE are B T=10 T; I P=6.5 MA; minimum flat top time=10 s, and maximum number of full-power, full-field pulses=3000 with 30 000 pulses at 2/3 full field. The baseline design is able to meet or exceed these objectives. All magnets are inertially cooled with liquid nitrogen and have the capability for an 18 s flat top at 10 T. The use of BeCu in the inner legs of the toroidal field (TF) coil also allows for a field of 12 T with a pulse length of 12 s. Extended pulse lengths at lower fields (e.g. 214 s at 4 T and 2 MA) will allow FIRE to explore advanced tokamak modes (Physics basis for the Fusion Ignition Research Experiment (FIRE) Plasma Facing Components, in: Twenty-first Symposium on Fusion Technology, Madrid, September, 2000).