Jena 2013 – wissenschaftliches Programm
P 6.2: Hauptvortrag
Dienstag, 26. Februar 2013, 14:30–15:00, HS 3
MHD Simulations of Edge Localized Modes in ASDEX Upgrade — •Matthias Hölzl1, Isabel Krebs1, Karl Lackner1, Sibylle Günter1, Guido Huysmans2, Ronald Wenninger3, and The ASDEX Upgrade Team1 — 1Max Planck Institute for Plasmaphysics, EURATOM Association, Boltzmannstr. 2, Garching, Germany — 2ITER Organisation, Route de Vinon sur Verdon, St-Paul-lez- Durance, France — 3Universitätssternwarte der Ludwig-Maximilians- Universität, München, Germany
In the high confinement mode, edge localized modes (ELMs) are observed at the plasma edge. As these may damage wall structures in future fusion devices, a detailed physical understanding is necessary.
We use the non-linear MHD code JOREK to study ELMs in realistic tokamak geometry. Toroidal mode numbers, poloidal filament sizes, and radial propagation speeds agree well with observations for type-I ELMs in ASDEX Upgrade. When a large number of toroidal harmonics is taken into account, a strong localization is found as also observed experimentally in ASDEX Upgrade. In the simulations, harmonics with low toroidal mode-numbers may be driven non-linearly to large energy levels. This is observed already in the early phase of the instability and can be explained by an interaction between several strong harmonics with adjacent toroidal mode numbers.
An outlook onto ongoing work is given. This includes further theory-experiment comparisons and the interaction between ELMs and external perturbation fields. The resistive wall model currently being implemented into JOREK is briefly presented.