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Title: Three-dimensional equilibria and island energy transport due to resonant magnetic perturbation edge localized mode suppression on DIII-D

Abstract

Experiments in the DIII-D tokamak show that the plasma responds to resonant magnetic perturbations (RMP) with toroidal mode numbers of n = 2 and n = 3 without field line reconnection, consistent with resistive magnetohydrodynamic predictions (MHD), while a strong nonlinear bifurcation is apparent when edge localized modes (ELM) are suppressed. The magnetic response associated with this bifurcation is localized to the high field side (HFS) of the machine and exhibits a dominant n = 1 component despite the application of a constant amplitude, slowly toroidally rotating, n = 2 applied field. The n = 1 mode is born locked to the vacuum vessel wall, while the n = 2 mode is entrained to the rotating field. Based on these magnetic response measurements, and Thomson scattering measurements of flattening of the electron temperature profile it is likely that these modes are magnetic island chains near the H-mode pedestal. The reduction in ∇Te occurs near the q = 4 and 5 rational surfaces, suggesting five unique islands are possible (m = 8, 9 or 10 for n = 2) and (m = 4 or 5 for n = 1). In all cases, the island width is estimated to be 2 ~more » 3 cm. The Chang-Callen calculated confinement degradation due to the presence of an individual island of this size is 8 ~ 12%, which is close to the 13 ~ 14% measured between the ELMing and suppressed states. This suggests that edge tearing modes may alter the pedestal causing peeling ballooning stability during resonant magnetic perturbation (RMP) induced ELM suppression.« less

Authors:
 [1];  [1];  [2];  [1];  [3];  [4];  [1];  [5];  [2];  [1];  [1];  [2];  [2];  [6];  [2];  [2];  [1]
  1. General Atomics, San Diego, CA (United States)
  2. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  3. Princeton Univ., NJ (United States)
  4. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  5. Columbia Univ., New York, NY (United States)
  6. Culham Science Centre, Culham Centre for Fusion Energy (CCFE), Abingdon (United Kingdom)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); General Atomics, San Diego, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES)
OSTI Identifier:
1302918
Alternate Identifier(s):
OSTI ID: 1226106; OSTI ID: 1372465
Grant/Contract Number:  
AC05-00OR22725; FC02-04ER54698; AC02-09CH11466; AC52-07NA27344; FG02-04ER54761
Resource Type:
Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 22; Journal Issue: 11; 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

King, J. D., Strait, E. J., Nazikian, R., Paz-Soldan, Carlos, Eldon, D., Fenstermacher, M. E., Ferraro, N. M., Hanson, J. M., Haskey, S. R., La Haye, R. J., Lanctot, Matthew J., Lazerson, Sam A., Logan, N. C., Liu, Y. Q., Okabayashi, M., Park, J. -K., and Turnbull, A. D. Three-dimensional equilibria and island energy transport due to resonant magnetic perturbation edge localized mode suppression on DIII-D. United States: N. p., 2015. Web. doi:10.1063/1.4935486.
King, J. D., Strait, E. J., Nazikian, R., Paz-Soldan, Carlos, Eldon, D., Fenstermacher, M. E., Ferraro, N. M., Hanson, J. M., Haskey, S. R., La Haye, R. J., Lanctot, Matthew J., Lazerson, Sam A., Logan, N. C., Liu, Y. Q., Okabayashi, M., Park, J. -K., & Turnbull, A. D. Three-dimensional equilibria and island energy transport due to resonant magnetic perturbation edge localized mode suppression on DIII-D. United States. doi:10.1063/1.4935486.
King, J. D., Strait, E. J., Nazikian, R., Paz-Soldan, Carlos, Eldon, D., Fenstermacher, M. E., Ferraro, N. M., Hanson, J. M., Haskey, S. R., La Haye, R. J., Lanctot, Matthew J., Lazerson, Sam A., Logan, N. C., Liu, Y. Q., Okabayashi, M., Park, J. -K., and Turnbull, A. D. Mon . "Three-dimensional equilibria and island energy transport due to resonant magnetic perturbation edge localized mode suppression on DIII-D". United States. doi:10.1063/1.4935486. https://www.osti.gov/servlets/purl/1302918.
@article{osti_1302918,
title = {Three-dimensional equilibria and island energy transport due to resonant magnetic perturbation edge localized mode suppression on DIII-D},
author = {King, J. D. and Strait, E. J. and Nazikian, R. and Paz-Soldan, Carlos and Eldon, D. and Fenstermacher, M. E. and Ferraro, N. M. and Hanson, J. M. and Haskey, S. R. and La Haye, R. J. and Lanctot, Matthew J. and Lazerson, Sam A. and Logan, N. C. and Liu, Y. Q. and Okabayashi, M. and Park, J. -K. and Turnbull, A. D.},
abstractNote = {Experiments in the DIII-D tokamak show that the plasma responds to resonant magnetic perturbations (RMP) with toroidal mode numbers of n = 2 and n = 3 without field line reconnection, consistent with resistive magnetohydrodynamic predictions (MHD), while a strong nonlinear bifurcation is apparent when edge localized modes (ELM) are suppressed. The magnetic response associated with this bifurcation is localized to the high field side (HFS) of the machine and exhibits a dominant n = 1 component despite the application of a constant amplitude, slowly toroidally rotating, n = 2 applied field. The n = 1 mode is born locked to the vacuum vessel wall, while the n = 2 mode is entrained to the rotating field. Based on these magnetic response measurements, and Thomson scattering measurements of flattening of the electron temperature profile it is likely that these modes are magnetic island chains near the H-mode pedestal. The reduction in ∇Te occurs near the q = 4 and 5 rational surfaces, suggesting five unique islands are possible (m = 8, 9 or 10 for n = 2) and (m = 4 or 5 for n = 1). In all cases, the island width is estimated to be 2 ~ 3 cm. The Chang-Callen calculated confinement degradation due to the presence of an individual island of this size is 8 ~ 12%, which is close to the 13 ~ 14% measured between the ELMing and suppressed states. This suggests that edge tearing modes may alter the pedestal causing peeling ballooning stability during resonant magnetic perturbation (RMP) induced ELM suppression.},
doi = {10.1063/1.4935486},
journal = {Physics of Plasmas},
number = 11,
volume = 22,
place = {United States},
year = {2015},
month = {11}
}

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Works referenced in this record:

Computation of three-dimensional tokamak and spherical torus equilibria
journal, May 2007

  • Park, Jong-kyu; Boozer, Allen H.; Glasser, Alan H.
  • Physics of Plasmas, Vol. 14, Issue 5
  • DOI: 10.1063/1.2732170

Experimental tests of linear and nonlinear three-dimensional equilibrium models in DIII-D
journal, July 2015

  • King, J. D.; Strait, E. J.; Lazerson, S. A.
  • Physics of Plasmas, Vol. 22, Issue 7
  • DOI: 10.1063/1.4923017

Reconstruction of current profile parameters and plasma shapes in tokamaks
journal, November 1985


Technical overview of the millimeter-wave imaging reflectometer on the DIII-D tokamak (invited)
journal, November 2014

  • Muscatello, C. M.; Domier, C. W.; Hu, X.
  • Review of Scientific Instruments, Vol. 85, Issue 11
  • DOI: 10.1063/1.4889735

Measurement and modeling of three-dimensional equilibria in DIII-D
journal, May 2011

  • Lanctot, M. J.; Reimerdes, H.; Garofalo, A. M.
  • Physics of Plasmas, Vol. 18, Issue 5
  • DOI: 10.1063/1.3593009

Initial results of the high resolution edge Thomson scattering upgrade at DIII-D
journal, October 2012

  • Eldon, D.; Bray, B. D.; Deterly, T. M.
  • Review of Scientific Instruments, Vol. 83, Issue 10
  • DOI: 10.1063/1.4738656

Calculations of two-fluid linear response to non-axisymmetric fields in tokamaks
journal, May 2012


An upgrade of the magnetic diagnostic system of the DIII-D tokamak for non-axisymmetric measurements
journal, August 2014

  • King, J. D.; Strait, E. J.; Boivin, R. L.
  • Review of Scientific Instruments, Vol. 85, Issue 8
  • DOI: 10.1063/1.4891817

Edge localized modes and the pedestal: A model based on coupled peeling–ballooning modes
journal, May 2002

  • Snyder, P. B.; Wilson, H. R.; Ferron, J. R.
  • Physics of Plasmas, Vol. 9, Issue 5
  • DOI: 10.1063/1.1449463

Advances in the physics understanding of ELM suppression using resonant magnetic perturbations in DIII-D
journal, January 2015


Modelling resonant field amplification due to low- n peeling modes in JET
journal, March 2010


Magnetic diagnostic system of the DIII-D tokamak
journal, February 2006

  • Strait, E. J.
  • Review of Scientific Instruments, Vol. 77, Issue 2
  • DOI: 10.1063/1.2166493

Validation of the linear ideal magnetohydrodynamic model of three-dimensional tokamak equilibria
journal, March 2010

  • Lanctot, M. J.; Reimerdes, H.; Garofalo, A. M.
  • Physics of Plasmas, Vol. 17, Issue 3
  • DOI: 10.1063/1.3335237

Full toroidal plasma response to externally applied nonaxisymmetric magnetic fields
journal, December 2010

  • Liu, Yueqiang; Kirk, A.; Nardon, E.
  • Physics of Plasmas, Vol. 17, Issue 12
  • DOI: 10.1063/1.3526677

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


Magnetic-flutter-induced pedestal plasma transport
journal, September 2013


Global energy confinement degradation due to macroscopic phenomena in tokamaks
journal, February 1990


Edge-localized mode dynamics and transport in the scrape-off layer of the DIII-D tokamak
journal, July 2005

  • Boedo, J. A.; Rudakov, D. L.; Hollmann, E.
  • Physics of Plasmas, Vol. 12, Issue 7
  • DOI: 10.1063/1.1949224

ELM particle and energy transport in the SOL and divertor of DIII-D
journal, August 2003

  • Fenstermacher, M. E.; Leonard, A. W.; Snyder, P. B.
  • Plasma Physics and Controlled Fusion, Vol. 45, Issue 9
  • DOI: 10.1088/0741-3335/45/9/304

Effects of resistivity and rotation on the linear plasma response to non-axisymmetric magnetic perturbations on DIII-D
journal, January 2015


Hybrid-like 2/1 flux-pumping and magnetic island evolution due to edge localized mode-neoclassical tearing mode coupling in DIII-D
journal, February 2012

  • King, J. D.; La Haye, R. J.; Petty, C. C.
  • Physics of Plasmas, Vol. 19, Issue 2
  • DOI: 10.1063/1.3684648

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


Observation of a Multimode Plasma Response and its Relationship to Density Pumpout and Edge-Localized Mode Suppression
journal, March 2015


Pedestal Bifurcation and Resonant Field Penetration at the Threshold of Edge-Localized Mode Suppression in the DIII-D Tokamak
journal, March 2015


ECE-imaging of the H-mode pedestal (invited)
journal, October 2012

  • Tobias, B. J.; Austin, M. E.; Boom, J. E.
  • Review of Scientific Instruments, Vol. 83, Issue 10
  • DOI: 10.1063/1.4733742

Comparisons of linear and nonlinear plasma response models for non-axisymmetric perturbations
journal, May 2013

  • Turnbull, A. D.; Ferraro, N. M.; Izzo, V. A.
  • Physics of Plasmas, Vol. 20, Issue 5
  • DOI: 10.1063/1.4805087

Progress on the application of ELM control schemes to ITER scenarios from the non-active phase to DT operation
journal, February 2014


Spatial and Temporal Structure of Edge-Localized Modes
journal, June 2004


Stability Limits of High-Beta Plasmas in DIII-D
journal, October 2005


Effect of island overlap on edge localized mode suppression by resonant magnetic perturbations in DIII-D
journal, May 2008

  • Fenstermacher, M. E.; Evans, T. E.; Osborne, T. H.
  • Physics of Plasmas, Vol. 15, Issue 5
  • DOI: 10.1063/1.2901064

Sustained suppression of type-I edge-localized modes with dominantly n = 2 magnetic fields in DIII-D
journal, July 2013


Resonant Pedestal Pressure Reduction Induced by a Thermal Transport Enhancement due to Stochastic Magnetic Boundary Layers in High Temperature Plasmas
journal, October 2009


Fast Ion Induced Shearing of 2D Alfvén Eigenmodes Measured by Electron Cyclotron Emission Imaging
journal, February 2011


Dimensionless scaling of the critical beta for onset of a neoclassical tearing mode
journal, August 2000

  • La Haye, R. J.; Buttery, R. J.; Guenter, S.
  • Physics of Plasmas, Vol. 7, Issue 8
  • DOI: 10.1063/1.874199

Anomalies in the applied magnetic fields in DIII-D and their implications for the understanding of stability experiments
journal, December 2003


A categorization of tearing mode onset in tokamaks via nonlinear simulation
journal, September 2005


A design retrospective of the DIII-D tokamak
journal, May 2002


Modelling of plasma response to resonant magnetic perturbation fields in MAST and ITER
journal, June 2011


Observation of Nonlinear Neoclassical Pressure-Gradient–Driven Tearing Modes in TFTR
journal, June 1995


Plasma response models for non-axisymmetric perturbations
journal, May 2012


Linear ideal MHD predictions for n = 2 non-axisymmetric magnetic perturbations on DIII-D
journal, February 2014


Measurement of the Resistive-Wall-Mode Stability in a Rotating Plasma Using Active MHD Spectroscopy
journal, September 2004


Edge stability and transport control with resonant magnetic perturbations in collisionless tokamak plasmas
journal, May 2006

  • Evans, Todd E.; Moyer, Richard A.; Burrell, Keith H.
  • Nature Physics, Vol. 2, Issue 6
  • DOI: 10.1038/nphys312

Boundary perturbations coupled to core 3/2 tearing modes on the DIII-D tokamak
journal, July 2013


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


Feedback stabilization of nonaxisymmetric resistive wall modes in tokamaks. I. Electromagnetic model
journal, September 2000

  • Liu, Y. Q.; Bondeson, A.; Fransson, C. M.
  • Physics of Plasmas, Vol. 7, Issue 9
  • DOI: 10.1063/1.1287744

Three-Dimensional Drift Kinetic Response of High- β Plasmas in the DIII-D Tokamak
journal, April 2015


Neoclassical tearing modes in Tokamak Fusion Test Reactor experiments. I. Measurements of magnetic islands and Δ
journal, April 1998

  • Chang, Z.; Fredrickson, E. D.; Batha, S. H.
  • Physics of Plasmas, Vol. 5, Issue 4
  • DOI: 10.1063/1.872627

Toroidal modeling of plasma response and resonant magnetic perturbation field penetration
journal, November 2012


    Works referencing / citing this record:

    Modelling of plasma response to 3D external magnetic field perturbations in EAST
    journal, October 2016


    Modal analysis of the full poloidal structure of the plasma response to n = 2 magnetic perturbations
    journal, July 2018

    • Munaretto, S.; Strait, E. J.; Haskey, S. R.
    • Physics of Plasmas, Vol. 25, Issue 7
    • DOI: 10.1063/1.5029381

    The density dependence of edge-localized-mode suppression and pump-out by resonant magnetic perturbations in the DIII-D tokamak
    journal, December 2019

    • Hu, Q. M.; Nazikian, R.; Grierson, B. A.
    • Physics of Plasmas, Vol. 26, Issue 12
    • DOI: 10.1063/1.5134767

    Equilibrium drives of the low and high field side n   =  2 plasma response and impact on global confinement
    journal, April 2016