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Title: 3D field phase-space control in tokamak plasmas

Abstract

Here, a small relaxation of the axisymmetric magnetic field of a tokamak into a non-axisymmetric three-dimensional (3D) configuration can be effective to control magnetohydrodynamic instabilities, such as edge-localized modes. However, a major challenge to the concept of 3D tokamaks is that there are virtually unlimited possible choices for a 3D magnetic field, and most of them will only destabilize or degrade plasmas by symmetry breaking. Here, we demonstrate the phase-space visualization of the full 3D field-operating windows of a tokamak, which allows us to predict which configurations will maintain high confinement without magnetohydrodynamic instabilities in an entire region of plasmas. We test our approach at the Korean Superconducting Tokamak Advanced Research (KSTAR) facility, whose 3D coils with many degrees of freedom in the coil space make it unique for this purpose. Our experiments show that only a small subset of coil configurations can accomplish edge-localized mode suppression without terminating the discharge with core magnetohydrodynamic instabilities, as predicted by the perturbative 3D expansion of plasma equilibrium and the optimizing principle of local resonance. The prediction provided excellent guidance, implying that our method can substantially improve the efficiency and fidelity of the 3D optimization process in tokamaks.

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [2];  [3];  [1];  [2];  [2];  [2];  [2];  [2];  [1];  [1];  [1];  [1]; ORCiD logo [1]
  1. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  2. National Fusion Research Institute, Daejeon (South Korea)
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1485109
Grant/Contract Number:  
[AC02-09CH11466]
Resource Type:
Accepted Manuscript
Journal Name:
Nature Physics
Additional Journal Information:
[ Journal Volume: 14; Journal Issue: 12]; Journal ID: ISSN 1745-2473
Publisher:
Nature Publishing Group (NPG)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Park, Jong -Kyu, Jeon, YoungMu, In, Yongkyoon, Ahn, Joon -Wook, Nazikian, Raffi, Park, Gunyoung, Kim, Jaehyun, Lee, HyungHo, Ko, WonHa, Kim, Hyun -Seok, Logan, Nikolas C., Wang, Zhirui, Feibush, Eliot A., Menard, Jonathan E., and Zarnstroff, Michael C. 3D field phase-space control in tokamak plasmas. United States: N. p., 2018. Web. doi:10.1038/s41567-018-0268-8.
Park, Jong -Kyu, Jeon, YoungMu, In, Yongkyoon, Ahn, Joon -Wook, Nazikian, Raffi, Park, Gunyoung, Kim, Jaehyun, Lee, HyungHo, Ko, WonHa, Kim, Hyun -Seok, Logan, Nikolas C., Wang, Zhirui, Feibush, Eliot A., Menard, Jonathan E., & Zarnstroff, Michael C. 3D field phase-space control in tokamak plasmas. United States. doi:10.1038/s41567-018-0268-8.
Park, Jong -Kyu, Jeon, YoungMu, In, Yongkyoon, Ahn, Joon -Wook, Nazikian, Raffi, Park, Gunyoung, Kim, Jaehyun, Lee, HyungHo, Ko, WonHa, Kim, Hyun -Seok, Logan, Nikolas C., Wang, Zhirui, Feibush, Eliot A., Menard, Jonathan E., and Zarnstroff, Michael C. Mon . "3D field phase-space control in tokamak plasmas". United States. doi:10.1038/s41567-018-0268-8. https://www.osti.gov/servlets/purl/1485109.
@article{osti_1485109,
title = {3D field phase-space control in tokamak plasmas},
author = {Park, Jong -Kyu and Jeon, YoungMu and In, Yongkyoon and Ahn, Joon -Wook and Nazikian, Raffi and Park, Gunyoung and Kim, Jaehyun and Lee, HyungHo and Ko, WonHa and Kim, Hyun -Seok and Logan, Nikolas C. and Wang, Zhirui and Feibush, Eliot A. and Menard, Jonathan E. and Zarnstroff, Michael C.},
abstractNote = {Here, a small relaxation of the axisymmetric magnetic field of a tokamak into a non-axisymmetric three-dimensional (3D) configuration can be effective to control magnetohydrodynamic instabilities, such as edge-localized modes. However, a major challenge to the concept of 3D tokamaks is that there are virtually unlimited possible choices for a 3D magnetic field, and most of them will only destabilize or degrade plasmas by symmetry breaking. Here, we demonstrate the phase-space visualization of the full 3D field-operating windows of a tokamak, which allows us to predict which configurations will maintain high confinement without magnetohydrodynamic instabilities in an entire region of plasmas. We test our approach at the Korean Superconducting Tokamak Advanced Research (KSTAR) facility, whose 3D coils with many degrees of freedom in the coil space make it unique for this purpose. Our experiments show that only a small subset of coil configurations can accomplish edge-localized mode suppression without terminating the discharge with core magnetohydrodynamic instabilities, as predicted by the perturbative 3D expansion of plasma equilibrium and the optimizing principle of local resonance. The prediction provided excellent guidance, implying that our method can substantially improve the efficiency and fidelity of the 3D optimization process in tokamaks.},
doi = {10.1038/s41567-018-0268-8},
journal = {Nature Physics},
number = [12],
volume = [14],
place = {United States},
year = {2018},
month = {9}
}

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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

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


Control of Asymmetric Magnetic Perturbations in Tokamaks
journal, November 2007


Nonlinear Interaction of Edge-Localized Modes and Turbulent Eddies in Toroidal Plasma under n = 1 Magnetic Perturbation
journal, August 2016


Comparative investigation of ELM control based on toroidal modelling of plasma response to RMP fields
journal, May 2017

  • Liu, Yueqiang; Kirk, A.; Li, Li
  • Physics of Plasmas, Vol. 24, Issue 5
  • DOI: 10.1063/1.4978884

Non-linear modeling of the plasma response to RMPs in ASDEX Upgrade
journal, September 2016


MHD-Limits to Plasma Confinement
journal, January 1984


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


The importance of matched poloidal spectra to error field correction in DIII-D
journal, July 2014

  • Paz-Soldan, C.; Lanctot, M. J.; Logan, N. C.
  • Physics of Plasmas, Vol. 21, Issue 7
  • DOI: 10.1063/1.4886795

A review of models for ELMs
journal, February 1998


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


Active Control of Type-I Edge-Localized Modes with n = 1 Perturbation Fields in the JET Tokamak
journal, June 2007


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

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


Toroidal self-consistent modeling of drift kinetic effects on the resistive wall mode
journal, November 2008

  • Liu, Yueqiang; Chu, M. S.; Chapman, I. T.
  • Physics of Plasmas, Vol. 15, Issue 11
  • DOI: 10.1063/1.3008045

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


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


Plasma transport in stochastic magnetic field caused by vacuum resonant magnetic perturbations at diverted tokamak edge
journal, October 2010

  • Park, G.; Chang, C. S.; Joseph, I.
  • Physics of Plasmas, Vol. 17, Issue 10
  • DOI: 10.1063/1.3487733

Nonlinear Transition from Mitigation to Suppression of the Edge Localized Mode with Resonant Magnetic Perturbations in the EAST Tokamak
journal, September 2016


Nonlinear error-field penetration in low density ohmically heated tokamak plasmas
journal, August 2012


Error field correction in DIII-D Ohmic plasmas with either handedness
journal, January 2011


Theory and simulation of quasilinear transport from external magnetic field perturbations in a DIII-D plasma
journal, April 2015

  • Waltz, R. E.; Ferraro, N. M.
  • Physics of Plasmas, Vol. 22, Issue 4
  • DOI: 10.1063/1.4917473

Neoclassical flows and transport in nonaxisymmetric toroidal plasmas
journal, January 1983


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


Mechanism of Edge Localized Mode Mitigation by Resonant Magnetic Perturbations
journal, September 2014


Edge localized modes (ELMs)
journal, February 1996


Self-consistent perturbed equilibrium with neoclassical toroidal torque in tokamaks
journal, March 2017

  • Park, Jong-Kyu; Logan, Nikolas C.
  • Physics of Plasmas, Vol. 24, Issue 3
  • DOI: 10.1063/1.4977898

Progress in the ITER Physics Basis
journal, June 2007


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

Stability and dynamics of the edge pedestal in the low collisionality regime: physics mechanisms for steady-state ELM-free operation
journal, August 2007


Small Denominators and Problems of Stability of Motion in Classical and Celestial Mechanics
journal, December 1963


Observation of Lobes near the X Point in Resonant Magnetic Perturbation Experiments on MAST
journal, June 2012


Impact of toroidal and poloidal mode spectra on the control of non-axisymmetric fields in tokamaks
journal, May 2017

  • Lanctot, M. J.; Park, J. -K.; Piovesan, P.
  • Physics of Plasmas, Vol. 24, Issue 5
  • DOI: 10.1063/1.4982688

Enhancement of helium exhaust by resonant magnetic perturbation fields at LHD and TEXTOR
journal, August 2016


Error field mode studies on JET, COMPASS-D and DIII-D, and implications for ITER
journal, November 1999


First Observation of Edge Localized Modes Mitigation with Resonant and Nonresonant Magnetic Perturbations in ASDEX Upgrade
journal, June 2011


The interaction of resonant magnetic perturbations with rotating plasmas
journal, March 1991

  • Fitzpatrick, R.; Hender, T. C.
  • Physics of Fluids B: Plasma Physics, Vol. 3, Issue 3
  • DOI: 10.1063/1.859863

Role of singular layers in the plasma response to resonant magnetic perturbations
journal, July 2012


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

Principal physics developments evaluated in the ITER design review
journal, May 2009


The KSTAR project: An advanced steady state superconducting tokamak experiment
journal, March 2000


Validation of Toroidal Rotation and Ion Temperature in KSTAR Plasmas
journal, April 2016

  • Lee, S. G.; H. H., Lee; W. H., Ko
  • Fusion Science and Technology, Vol. 69, Issue 2
  • DOI: 10.13182/FST15-174

Error Field Amplification and Rotation Damping in Tokamak Plasmas
journal, May 2001


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


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


Corrigendum: Error field correction in DIII-D Ohmic plasmas with either handedness
journal, June 2012


Nonambipolar Transport by Trapped Particles in Tokamaks
journal, February 2009


Extremely low intrinsic non-axisymmetric field in KSTAR and its implications
journal, March 2015