Non-linear modeling of the threshold between ELM mitigation and ELM suppression by Resonant Magnetic Perturbations in ASDEX Upgrade

Abstract

The interaction between Edge Localized Modes (ELMs) and Resonant Magnetic Perturbations (RMPs) is modeled with the magnetohydrodynamic code JOREK using experimental parameters from ASDEX Upgrade discharges. The ELM mitigation or suppression is optimal when the amplification of both tearing and peeling-kink responses result in a better RMP penetration. The ELM mitigation or suppression is not only due to the reduction of the pressure gradient, but predominantly arises from the toroidal coupling between the ELMs and the RMP-induced mode at the plasma edge, forcing the edge modes to saturate at a low level. The bifurcation from ELM mitigation to ELM suppression is observed when the RMP amplitude is increased. ELM mitigation is characterized by rotating modes at the edge, while the mode locking to RMPs is induced by the resonant braking of the electron perpendicular flow in the ELM suppression regime.

References in corpus (6)

• Observation of lobes near the X-point in resonant magnetic perturbation experiments on MAST
• Experimental conditions to suppress edge localised modes by magnetic perturbations in the ASDEX Upgrade tokamak
• Effect of resonant magnetic perturbations on low collisionality discharges in MAST and a comparison with ASDEX Upgrade
• Non-linear modeling of the plasma response to RMPs in ASDEX Upgrade
• Nonlinear excitation of low-n harmonics in reduced magnetohydrodynamic simulations of edge-localized modes
• Towards understanding edge localised mode mitigation by resonant magnetic perturbations in MAST

Cited by in corpus (7)

• The JOREK non-linear extended MHD code and applications to large-scale instabilities and their control in magnetically confined fusion plasmas
• The Density Dependence of Edge-Localized-Mode Suppression and Pump-out by Resonant Magnetic Perturbations in the DIII-D Tokamak
• The Role of Edge Resonant Magnetic Perturbations in Edge-Localized-Mode Suppression and Density Pump-out in low-collisionality DIII-D Plasmas
• MHD simulations of small ELMs at low triangularity in ASDEX Upgrade
• Theory of Edge Localized Mode Suppression by Static Resonant Magnetic Perturbations in the DIII-D Tokamak
• Comparing spontaneous and pellet-triggered ELMs via non-linear extended MHD simulations
• Role of the edge electric field in the resonant mode-particle interactions and the formation of transport barriers in toroidal plasmas