FINITE-ELEMENT MODELING OF THE PLASMA EDGE

Analysis of particle- and energy-transport in tokamak plasmas shows the importance of the scrape-off layer (SOL) to achieve satisfying conditions for a burning plasma in a fusion reactor. To take into account the influence of complex geometrical features on transport, we developed a 2D-fluid-code based on a Finite Element Method (FEM). Because this numerical scheme needs no regular grid structure, one can deal much more accurately with the plasma flow in non simply connected domains and near limiter- or divertor-plates, where the magnetic field is inclined to the target. This permits a geometrically and physically more realistic description of the interaction of plasma- and neutral-particles. Results from a coupled calculation between the FEM-code and a neutral-gas Monte-Carlo-code (EIRENE) are discussed for the SOL of TEXTOR.