Experimental conditions to suppress edge localised modes by magnetic perturbations in the ASDEX Upgrade tokamak

  title={Experimental conditions to suppress edge localised modes by magnetic perturbations in the ASDEX Upgrade tokamak},
  author={Wolfgang Suttrop and A. Kirk and V. Bobkov and Marco Cavedon and Mike G Dunne and R. M. McDermott and H. Meyer and Raffi Nazikian and Carlos Paz-Soldan and David Anthony Ryan and Eleonora Viezzer and Matthias Willensdorfer},
  journal={Nuclear Fusion},
Access conditions for full suppression of edge localised modes (ELMs) by magnetic perturbations (MP) in low density high confinement mode (H-mode) plasmas are studied in the ASDEX Upgrade tokamak. The main empirical requirements for full ELM suppression in our experiments are: 1. The poloidal spectrum of the MP must be aligned for best plasma response from weakly stable kink-modes, which amplify the perturbation, 2. The plasma edge density must be below a critical value, m−3. The edge… 

Wide Operational Windows of Edge-Localized Mode Suppression by Resonant Magnetic Perturbations in the DIII-D Tokamak.

The model predicts that wide q_{95} windows of ELM suppression can be achieved at substantially higher pedestal pressure in DIII-D by shifting to higher toroidal mode number (n=4) RMPs.

Predicting operational windows of ELMs suppression by resonant magnetic perturbations in the DIII-D and KSTAR tokamaks

A newly developed plasma response model, combining the nonlinear two-fluid MHD code TM1 and toroidal MHD code GPEC run in ideal mode, quantitatively predicts the narrow isolated q95 windows (Δq95 ∼

Dependence of the L–H power threshold on the alignment of external non-axisymmetric magnetic perturbations in ASDEX Upgrade

Experiments at ASDEX Upgrade have been conducted to study the impact of the alignment of external magnetic perturbations (MPs) with n = 2 toroidal mode symmetry on the power threshold of the


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Non-linear free boundary simulations of the plasma response to resonant magnetic perturbations in ASDEX Upgrade plasmas

A promising method for the control of Edge Localized Modes (ELMs) in H-Mode tokamak plasmas is the application of Resonant Magnetic Perturbations (RMPs), where small helical field perturbations are

Pedestal electron collisionality and toroidal rotation during ELM-crash suppression phase under n = 1 RMP in KSTAR

Excellent reproducibility of KSTAR resonant magnetic perturbation (RMP)-driven, edge-localized mode (ELM)-crash suppression enables us to construct a database reliably for the study of ELM-crash

Helically localized ballooning instabilities in three-dimensional tokamak pedestals

Recent experimental observations have found toroidally localized MHD instabilities in the plasma edge during operation with applied magnetic perturbations on ASDEX Upgrade in H-mode with low

The role of edge resonant magnetic perturbations in edge-localized-mode suppression and density pump-out in low-collisionality DIII-D plasmas

Two-fluid nonlinear MHD simulations using the TM1 code demonstrate that the formation of magnetic islands at the top and bottom of the H-mode pedestal, together with the strong screening of resonant

Effect of magnetic perturbations for ELM control on divertor power loads, detachment and consequences of field penetration in ASDEX Upgrade

Magnetic perturbation (MP) fields are currently studied in ASDEX Upgrade and many other tokamaks in terms of edge localized mode control and the implication onto steady state divertor power load and

Plasma response to resonant magnetic perturbations near rotation zero-crossing in low torque plasmas

Plasma response to resonant magnetic perturbations (RMPs) near the pedestal top is crucial for accessing edge localized modes (ELMs) suppression in tokamaks. Since radial location of relevant



Experimental studies of high-confinement mode plasma response to non-axisymmetric magnetic perturbations in ASDEX Upgrade

The interaction of externally applied small non-axisymmetric magnetic perturbations (MP) with tokamak high-confinement mode (H-mode) plasmas is reviewed and illustrated by recent experiments in ASDEX

Identification of plasma-edge-related operational regime boundaries and the effect of edge instability on confinement in ASDEX Upgrade

Local edge parameters on the ASDEX Upgrade tokamak are investigated at the L-mode to H-mode transition, during phases with various types of edge-localized modes (ELMs), and at the density limit. A

Parameter dependence of ELM loss reduction by magnetic perturbations at low pedestal density and collisionality in ASDEX upgrade

ELM mitigation by magnetic perturbations is studied at low pedestal collisionalities down to ITER-like values ( ν e , PED * = 0.1 ) in ASDEX Upgrade. A comprehensive database of ELM energy losses for

Effect of resonant magnetic perturbations on low collisionality discharges in MAST and a comparison with ASDEX Upgrade

Sustained edge localized mode (ELM) mitigation has been achieved on MAST and AUG using resonant magnetic perturbations (RMPs) with various toroidal mode numbers over a wide range of low to medium

Ideal magnetohydrodynamic stability of the tokamak high-confinement-mode edge region

The ideal magnetohydrodynamic (MHD) stability of the tokamak edge is analyzed, with particular emphasis on radially localized instabilities; it is proposed that these are responsible for edge

Sustained suppression of type-I edge-localized modes with dominantly n = 2 magnetic fields in DIII-D

Type-I edge-localized modes (ELMs) have been suppressed in DIII-D (Luxon et al 2003 Nucl. Fusion 43 1813) H-mode discharges with a H98Y2 confinement factor near 1.0 using magnetic perturbations (MPs)

Effect of island overlap on edge localized mode suppression by resonant magnetic perturbations in DIII-D

Recent DIII-D [J. L. Luxon et al., Nucl. Fusion 43, 1813 (2003)] experiments show a correlation between the extent of overlap of magnetic islands induced in the edge plasma by perturbation coils and

Advances in the physics understanding of ELM suppression using resonant magnetic perturbations in DIII-D

Recent experiments on DIII-D have increased confidence in the ability to suppress edge-localized modes (ELMs) using edge-resonant magnetic perturbations (RMPs) in ITER, including an improved physics

Connection between plasma response and resonant magnetic perturbation (RMP) edge localized mode (ELM) suppression in DIII-D

Calculations of the plasma response to applied non-axisymmetric fields in several DIII-D discharges show that predicted displacements depend strongly on the edge current density. This result is found