EVALUATION OF MAGNET LOSSES FROM HE-II TEMPERATURE-MEASUREMENTS IN TORE-SUPRA

The toroidal field system of the French tokamak TORE SUPRA is cooled b y superfluid helium. A particular behaviour has been observed during s afety discharges in one of the 18 coils (BT13) of the system, in relat ion to a higher level of He II temperatures. Thanks to external temper ature sensors and to the Gorter Mellink conduction in the cooling chan nels, it has been possible to make a thermal evaluation using a calori metric method. An hypothesis for the defect inside the coil is present ed and discussed taking into account a campaign of safety discharges p erformed in Summer 1993. (C) 1998 Elsevier Science Ltd. All rights res erved.