Time Evolution of Tokamak Plasmas in the Presence of 3D Conducting Structures

This paper presents a method for the simulation of the time evolution of fusion plasmas in the presence of eddy currents induced in nonmagnetic 3D structures. The plasma is assumed to be 2D axisymmetric. The interaction between the plasma and the external currents is assumed to occur via the magnetic field averaged through the toroidal angle. The average poloidal field is computed by means of a 2D axisymmetric differential FEM formulation in terms of the poloidal magnetic flux. The 3D induced currents are calculated via an integral edge-element formulation in terms of a two-component current density vector potential. The method is also applied to derive a linearized plasma response model for the control of the plasma current position and shape in the presence of 3D conducting structures