Abstract Details
Abstracts
Author: Henry Strauss
Requested Type: Pre-Selected Invited
Submitted: 2019-02-21 07:11:54
Co-authors:
Contact Info:
HRS Fusion
2 Januson Ct.
West Orange, NJ 07052
United States
Abstract Text:
Two critical issues in ITER disruptions are the
thermal load during the thermal quench (TQ) and the asymmetric wall
force produced during the current quench (CQ).
Simulations and theory indicate that both effects depend on the resistive
wall penetration time.
JET data from the ILW 2011-2016 disruption database shows the decrease of wall force
with decreasing CQ time, when the CQ time is less than the
resistive wall penetration time.
Recent 3D MHD simulations of thermal quench in JET have been performed
and compared to experiment,
and are reasonable agreement.
The simulations and theory show that the TQ time depends on the the resistive wall time
to a fractional power.
The TQ occurs when magnetic surfaces break, allowing heat to be conducted to the wall.
Although the magnetic field has had time to fully penetrate the wall at the beginning
of the TQ, it has relatively small amplitude at the wall. The magnetic field perturbations
at the wall caused by loss of equilibrium grow to a significant amplitude
in a fraction of the resistive wall time.
The results imply that in ITER, with 50 times longer resistive wall time
than in JET, the asymmetric wall force and TQ time could be an order of
magnitude longer than in JET.
This might relax the requirements for disruption mitigation and runaway electron avoidance.
Comments:
