Engineering overview of the fusion ignition research experiment (FIRE)

The FIRE tokamak is an option for the next step in the U.S. magnetic fusion energy program. The design goals have evolved to a major radius of 2.14 m, minor radius of 0.525 m, toroidal field (TF) of 10 T and plasma current of 7.7 mA for a flat-top time of ∼20 s. The requirement for 3000 full-power, full-field pulses and 30,000 pulses at 2/3 of full field has been retained since 1999. All magnets are inertially cooled with liquid nitrogen. Design options have been considered over a range of parameter space for either a wedged TF coil structure or a bucked and wedged TF/Central Solenoid structure. The wedged configuration has been selected as the baseline.