Scoping study of a 12T toroidal field coil for the fusion engineering test facility

A scoping study of a 12T TF Coil for ETF has been performed. Major design drivers included: High field (12T) and overall current density (1700 A/cm²) Large mechanical forces due to field, current density and coil size(6×10m bore) Stability against a 100 mj/cm³disturbance deposited over a half turn Ability to survive poloidal field pulses and plasma disruptions without quenching Significant conclusions reached during the study were: Pool boiling cooling of a Nb³Sn conductor is preferable to supercritical or superfluid cooling because it leads to a cheaper, more reliable system Distributed structure is required to support the conductor Most of the losses resulting from a plasma disruption are dissipated in the coil case Testing should be performed on the full-size conductor to eliminate the need for extrapolation.