skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Effect of magnetic perturbations on turbulence-flow dynamics at the L-H transition on DIII-D

Abstract

Detailed 2D turbulence measurements from the DIII-D tokamak provide an explanation for how resonant magnetic perturbations (RMPs) raise the L-H power threshold P LH [P. Gohil et al., Nucl. Fusion 51, 103020 (2011)] in ITER-relevant, low rotation, ITER-similar-shape plasmas with favorable ion B direction. RMPs simultaneously raise the turbulence decorrelation rate Δ ω D and reduce the flow shear rate ω shear in the stationary L-mode state preceding the L-H transition, thereby disrupting the turbulence shear suppression mechanism. RMPs also reduce the Reynolds stress drive for poloidal flow, contributing to the reduction of ω shear . On the ~100 μs timescale of the L-H transition, RMPs reduce Reynolds-stress-driven energy transfer from turbulence to flows by an order of magnitude, challenging the energy depletion theory for the L-H trigger mechanism. In contrast, non-resonant magnetic perturbations, which do not significantly affect P LH , do not affect Δ ω D and only slightly reduce ω shear and Reynolds-stress-driven energy transfer.<

Authors:
ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [1];  [1]; ORCiD logo [1]; ORCiD logo [1]
  1. Univ. of Wisconsin, Madison, WI (United States)
  2. Univ. of California, Los Angeles, CA (United States)
Publication Date:
Research Org.:
General Atomics, San Diego, CA (United States); Univ. of Wisconsin, Madison, WI (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES)
OSTI Identifier:
1631960
Alternate Identifier(s):
OSTI ID: 1631774
Grant/Contract Number:  
FC02-04ER54698; FG02-08ER54999; SC0001288
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 27; Journal Issue: 6; Conference: 61. Annual Meeting of the APS Division of Plasma Physics, Fort Lauderdale, FL (United States), 21-25 Oct 2019; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Kriete, David M., McKee, George R., Schmitz, Lothar, Smith, D. R., Yan, Z., Morton, L. A., and Fonck, R. J. Effect of magnetic perturbations on turbulence-flow dynamics at the L-H transition on DIII-D. United States: N. p., 2020. Web. doi:10.1063/1.5145207.
Kriete, David M., McKee, George R., Schmitz, Lothar, Smith, D. R., Yan, Z., Morton, L. A., & Fonck, R. J. Effect of magnetic perturbations on turbulence-flow dynamics at the L-H transition on DIII-D. United States. https://doi.org/10.1063/1.5145207
Kriete, David M., McKee, George R., Schmitz, Lothar, Smith, D. R., Yan, Z., Morton, L. A., and Fonck, R. J. Wed . "Effect of magnetic perturbations on turbulence-flow dynamics at the L-H transition on DIII-D". United States. https://doi.org/10.1063/1.5145207. https://www.osti.gov/servlets/purl/1631960.
@article{osti_1631960,
title = {Effect of magnetic perturbations on turbulence-flow dynamics at the L-H transition on DIII-D},
author = {Kriete, David M. and McKee, George R. and Schmitz, Lothar and Smith, D. R. and Yan, Z. and Morton, L. A. and Fonck, R. J.},
abstractNote = {Detailed 2D turbulence measurements from the DIII-D tokamak provide an explanation for how resonant magnetic perturbations (RMPs) raise the L-H power threshold P LH [P. Gohil et al., Nucl. Fusion 51, 103020 (2011)] in ITER-relevant, low rotation, ITER-similar-shape plasmas with favorable ion ∇ B direction. RMPs simultaneously raise the turbulence decorrelation rate Δ ω D and reduce the flow shear rate ω shear in the stationary L-mode state preceding the L-H transition, thereby disrupting the turbulence shear suppression mechanism. RMPs also reduce the Reynolds stress drive for poloidal flow, contributing to the reduction of ω shear. On the ~100 μs timescale of the L-H transition, RMPs reduce Reynolds-stress-driven energy transfer from turbulence to flows by an order of magnitude, challenging the energy depletion theory for the L-H trigger mechanism. In contrast, non-resonant magnetic perturbations, which do not significantly affect P LH, do not affect Δ ω D and only slightly reduce ω shear and Reynolds-stress-driven energy transfer.<},
doi = {10.1063/1.5145207},
url = {https://www.osti.gov/biblio/1631960}, journal = {Physics of Plasmas},
issn = {1070-664X},
number = 6,
volume = 27,
place = {United States},
year = {2020},
month = {6}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 1 work
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Suppression of Edge Localized Modes in High-Confinement KSTAR Plasmas by Nonaxisymmetric Magnetic Perturbations
journal, July 2012


Turbulence velocimetry of density fluctuation imaging data
journal, October 2004


Structure and scaling properties of the geodesic acoustic mode
journal, March 2006


Overview of KSTAR research progress and future plans toward ITER and K-DEMO
journal, July 2019


Plasma fluctuation measurements in tokamaks using beam‐plasma interactions
journal, November 1990


Three‐dimensional fluid simulations of the nonlinear drift‐resistive ballooning modes in tokamak edge plasmas
journal, October 1993


Fast ion transport during applied 3D magnetic perturbations on DIII-D
journal, June 2015


Fast Low-to-High Confinement Mode Bifurcation Dynamics in a Tokamak Edge Plasma Gyrokinetic Simulation
journal, April 2017


Electron temperature gradient driven turbulence
journal, May 2000


Interaction between a low-frequency electrostatic mode and resonant magnetic perturbations in MAST
journal, August 2012


OMFIT Tokamak Profile Data Fitting and Physics Analysis
journal, January 2018


Gyrokinetic GENE simulations of DIII-D near-edge L-mode plasmas
journal, September 2019


Magnetic perturbation experiments on MAST L- and H-mode plasmas using internal coils
journal, April 2011


Effects of resonant magnetic perturbations on turbulence and transport in DIII-D L-mode plasmas
journal, October 2015


Detection of zonal flow spectra in DIII-D by a dual-channel Doppler backscattering system
journal, October 2008


Theory of mean poloidal flow generation by turbulence
journal, July 1991


Zonal flow triggers the L-H transition in the Experimental Advanced Superconducting Tokamak
journal, July 2012


Properties of high-β microturbulence and the non-zonal transition
journal, October 2013


RMP ELM suppression in DIII-D plasmas with ITER similar shapes and collisionalities
journal, January 2008


Recent progress towards a physics-based understanding of the H-mode transition
journal, January 2016


Study of in-vessel nonaxisymmetric ELM suppression coil concepts for ITER
journal, January 2008


Evidence of Toroidally Localized Turbulence with Applied 3D Fields in the DIII-D Tokamak
journal, September 2016


L–H transition studies on DIII-D to determine H-mode access for operational scenarios in ITER
journal, August 2011


Drift waves and transport
journal, April 1999


Particle image velocimetry with optical flow
journal, August 1998


A novel, multichannel, comb-frequency Doppler backscatter system
journal, October 2010


Parallel electron force balance and the L-H transition
journal, May 2016


Role of Zonal Flow Predator-Prey Oscillations in Triggering the Transition to H-Mode Confinement
journal, April 2012


Zonal flows in plasma—a review
journal, April 2005


Role of trapped electron mode turbulence in internal transport barrier control in the Alcator C-Mod Tokamak
journal, May 2004


Influence of sheared poloidal rotation on edge turbulence
journal, January 1990


Experimental studies of high-confinement mode plasma response to non-axisymmetric magnetic perturbations in ASDEX Upgrade
journal, November 2016


Wide-field turbulence imaging with beam emission spectroscopy
journal, October 2010


Self-Regulating Shear Flow Turbulence: A Paradigm for the L to H Transition
journal, April 1994


Regime of Improved Confinement and High Beta in Neutral-Beam-Heated Divertor Discharges of the ASDEX Tokamak
journal, November 1982


Enhanced understanding of non-axisymmetric intrinsic and controlled field impacts in tokamaks
journal, August 2017


Nonlinear transfer in heated L-modes approaching the L–H transition threshold in Alcator C-Mod
journal, June 2015


Effects of applied error fields on the H-mode power threshold of JFT-2M
journal, August 1991


The beam emission spectroscopy diagnostic on the DIII-D tokamak
journal, January 1999


Integrated modeling applications for tokamak experiments with OMFIT
journal, July 2015


Long-range correlations and edge transport bifurcation in fusion plasmas
journal, May 2011


Edge-localized-modes in tokamaks
journal, September 2014


Gyrokinetic simulation of momentum transport with residual stress from diamagnetic level velocity shears
journal, April 2011


BOUT++: A framework for parallel plasma fluid simulations
journal, September 2009


Extracting the turbulent flow-field from beam emission spectroscopy images using velocimetry
journal, October 2018


Spatial transfer function for the beam emission spectroscopy diagnostic on DIII-D
journal, October 2006


Effect of ion ∇B drift direction on density fluctuation poloidal flow and flow shear
journal, June 2005


A review of theories of the L-H transition
journal, December 1999


A quarter-century of H-mode studies
journal, November 2007


L–H transition in the presence of magnetic perturbations in ASDEX Upgrade
journal, October 2012


New plasma measurements with a multichannel millimeter-wave fluctuation diagnostic system in the DIII-D tokamak (invited)
journal, October 2010


Density fluctuation measurements via beam emission spectroscopy (invited)
journal, October 1992


L–H threshold studies in NSTX
journal, October 2011


Energy exchange dynamics across L–H transitions in NSTX
journal, May 2017


The effect of magnetic flutter on residual flow
journal, November 2013


A theory-based transport model with comprehensive physics
journal, May 2007


Suppression of Large Edge-Localized Modes in High-Confinement DIII-D Plasmas with a Stochastic Magnetic Boundary
journal, June 2004


3D field induced collisionless zonal flow decay in tokamak plasmas
journal, December 2017


Power requirement for accessing the H-mode in ITER
journal, July 2008


Zonal Flows and Transient Dynamics of the L H Transition
journal, May 2003


3D vacuum magnetic field modelling of the ITER ELM control coil during standard operating scenarios
journal, August 2013


Plasma rotation profile measurements using Doppler reflectometry
journal, April 2004


LH transition trigger physics in ITER-similar plasmas with applied n   =  3 magnetic perturbations
journal, September 2019


Potential Vorticity Mixing in a Tangled Magnetic Field
journal, March 2020