A RADIALLY CONTINUOUS 2-CHAMBER MODEL FOR THE HIGH-RECYCLING DIVERTOR EDGE LAYER

A radially continuous two-chamber model for the edge layer of a high recycling divertor tokamak is presented. Diffusive radial transport is chosen for the plasma in the main chamber as well as for the neutral gas in the divertor. Both regions are coupled by parallel conductive energy flow and subsonic particle flow. Standard sheath conditions at the target plate are used. Radial profiles of all relevant quantities are obtained including the self-consistent parallel flow velocity, which can be locally positive or negative. The existence of stationary solutions, their stability and dependence on boundary conditions are investigated. The applicability as an advanced edge model for large radial transport codes is tested.