August 27, 2017 to September 1, 2017
RAI Congress Center, Amsterdam, The Netherlands
Europe/Amsterdam timezone

Study of the Hotspot Temperature during Quench in the Non-Planar Coils of W7-X

Aug 29, 2017, 1:15 PM
1h 45m
Posters Area

Posters Area

Poster Presentation of 1h45m B1 - Superconducting Magnets for Fusion Tue-Af-Po2.03


Kamil Sedlak (Paul Scherrer Institut, Switzerland)


The quench protection system of the non-planar coils of the Wendelstein 7-X stellarator was laid out over fifteen years ago. At that time, the assessment of the hot spot temperature by a basic adiabatic model was done using design values for material and operation parameters. After the operating experience in 2016, the hot spot temperature is re-assessed with the thermal-hydraulic program THEA, using the actual values for delay and dump time. The electrical resistivity of the conduit alloy is measured over the whole range of temperature and in magnetic field on relevant samples of conductor, exposed to the hardening heat treatment after winding. The results are fed into Thea. Parametric variations are studied in the calculations, e.g. testing the effect of the operation current, quench initiation zone and dump resistor. The results suggest that the hot spot temperature of the conduit in case of quench is safely within the allowable values even in case the dump voltage is reduced compared to the initial design value.

Submitters Country Switzerland

Primary authors

Kamil Sedlak (Paul Scherrer Institut, Switzerland) Pierluigi Bruzzone (EPFL-CRPP) Thomas Rummel (Max-Planck-Institute for Plasma Physics)

Presentation materials