Response of a Partial Wall to an External Perturbation of Rotating Plasma
Authors: L. Zakharov and C.V. Atanasiu
Abstract:
In this paper, we present the response of a 3D thin multiply connected wall to an external kink
mode perturbation in axisymmetric tokamak configurations. To calculate the contribution of the
plasma perturbed magnetic field in the vacuum region, we have made use of the concept of surface
currents [following C. V. Atanasiu, A. H. Boozer, L. E. Zakharov, and A. A. Subbotin, Phys.
Plasmas 6 , 2781 (1999)]. The wall response is expressed in terms of a stream function of the wall
surface currents, which are obtained by solving a diffusion type equation, taking into account the
contribution of the wall currents themselves iteratively. The use of stream function makes the
approach applicable for both well-studied earlier Resistive Wall Modes and for Wall Touching
Kink Modes, which were discovered recently as a key phenomenon in disruptions [L. E. Zakharov,
S. A. Galkin, and S. N. Gerasimov, Phys. Plasmas 19 , 055703 (2012)]. New analytical expressions,
suitable for numerical calculations of toroidal harmonics of the vacuum magnetic fields from the
surface currents on axisymmetric shells, are derived. 2013 AIP Publishing LLC .
__________________________________________________
Submitted to: Physics of Plasmas (August 2013)
__________________________________________________
Download PPPL-4971 (pdf 275 KB 11 pp)
__________________________________________________