Experimental thermal behaviour of the toroidal field model coil: application to ITER TF transient regimes

The ITER Toroidal Field (TF) magnet is made of 18 coils. The 7 winding-pack modules constituting their structure, contain each one double pancake cable-in-conduit conductor (CICC) inserted in a stainless steel radial plate. The winding pack is enclosed inside a thick stainless steel case. During a safety discharge of the TF system, eddy currents and associated heat generation are induced in the plates and in the case. Such fast discharges have been performed during Phase I and Phase II experiment of the Toroidal Field Model Coil (TFMC) tests, respectively without and with an additional background coil (LCT), in order to investigate heat generation and transfer. Simple models have been developed to predict the behaviour of the coil during these transients. These models have been validated by calorimetric measurements. In addition, for the TF Coil, during a plasma disruption which induces here also an instantaneous heat deposition, these models can be used to estimate the temperature increase of the TF Conductor and investigate whether a quench can happen. (authors)