Linear analysis of the interaction of rotating helical magnetic perturbations with tokamak plasmas based on the reduced two-fluid MHD model

The error-field penetration process of the DED (Dynamic Ergodic Divertor) into tokamak plasmas has been investigated in terms of numerical simulations based on a linearized reduced set of two-fluid equations (three-field, four-field model) in cylindrical coordinates, in which effects of electron diamagnetic drift are taken into account. Localized radial structures of the perturbations were identified in the vicinity of the rational surface when increasing the plasma viscosity and the density diffusivity. Resonant characteristics of the dependencies of the induced force by the DED on the driving frequency of the DED were also found. It is shown that the force transfers from the DED to the tokamak plasmas so as to bring electron fluid to the rest frame of the DED-field. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim