2D MODELING OF THE ASDEX-UPGRADE SCRAPE-OFF LAYER AND DIVERTOR PLASMA

Due to the open field lines, the scrape-off layer and divertor region of tokamak plasmas is a complex, two-dimensional system, involving tra nsport parallel and perpendicular to the magnetic field, as well as in teraction of the plasma with surfaces and with the neutral gas. Theref ore sophisticated two-dimensional codes are required to model the dive rtor and edge physics. In this paper, the B2-EIRENE code package is us ed to simulate the ASDEX-Upgrade scrape-off layer plasma and the neutr al gas dynamics in a fully self-consistent way. Specific ASDEX-Upgrade discharges are modelled using the actual magnetic configuration and i n-vessel components. Single fluid as well as multifluid calculations i ncluding self-consistent target and wall erosion of carbon are describ ed. At given input power and bulk plasma radiation, typical divertor p lasma profiles from Langmuir probes are fitted by varying the separatr ix density and the transport coefficients. On the basis of such multif luid fits, spectroscopic divertor diagnostics are numerically modelled and compared with measured profiles, and reasonable agreement is foun d.