Support of modelling of MHD evolution of disruptions, eddy currents and halo currents
An investigation was made of the stability properties of the International Thermonuclear Experimental Reactor (ITER) equilibria within the framework of the neoclassical tearing mode theory. It was shown that the tearing mode experiences a stabilizing mechanism during its growth, which is due to the flattening of the equilibrium profile and which is proportional to the island width w times log w. It appears from experimental evidences as well as from numerical simulations that the quasi-linear stabilization mechanism may turn out to be too weak to provide an acceptable saturation width for the 3/2, 2/1 and 4/3 modes in ITER. A formalism was developed for applying resistive wall boundary conditions to nonlinear restive codes such as NIMROD and MH3D. The approach is similar to the one used for linear codes; it is based on solving the plasma equation inside a closed volume which is assumed to be toroidally symmetric. Provision has been made to incorporate a driven response to toroidally symmetric external coils using a one-component potential vector field representation. It is proposed that the resistive wall boundary conditions be implemented as natural explicit boundary conditions into NIMROD.
Bibliographic Reference: Report: LRP 614/98 EN (1998) 44pp.
Availability: Available from the Ecole Polytechnique Fédérale de Lausanne, Lausanne (CH)
Record Number: 199811289 / Last updated on: 1998-10-27
Original language: en
Available languages: en