Analysis and optimization of the impact of ferromagnetic inserts on the toroidal field ripple in the International Thermonuclear Experimental Reactor

Abstract

Perturbations of the axial symmetry of a toroidal magnetic field, or the toroidal field (TF) ripple, in tokamaks can potentially lead to losses of high-energy particles from the plasma. These losses can be significant and are one of the major concerns with respect to both the energy blance of the deuterium–tritium plasma and the heat load limits in the International Thermonuclear Experimental Reactor (ITER). In the ITER design, ferromagnetic inserts are used to reduce the TF ripple. In this work the impact of the ferromagnetic inserts on the TF ripple in the ITER is analysed to optimize their filling factor within the design constraints. The analysis of the high-mode spectrum of the amplitudes of ripple high modes is also carried out.