Reduced-magnetohydrodynamic simulations of toroidally and poloidally localized edge localized modes

摘要

We use the non-linear reduced-magnetohydrodynamic code JOREK to study edge localized modes (ELMs) in the geometry of the ASDEX Upgrade tokamak. Toroidal mode numbers, poloidal filament sizes, and radial propagation speeds of filaments into the scrape-off layer are in good agreement with observations for type-I ELMs in ASDEX Upgrade. The observed instabilities exhibit a toroidal and poloidal localization of perturbations which is compatible with the solitary magnetic perturbations recently discovered in ASDEX Upgrade [R. Wenninger, Solitary magnetic perturbations at the ELM onset, Nucl. Fusion (accepted)]. This localization can only be described in numerical simulations with high toroidal resolution.