Measurements of the toroidal torque balance of error field penetration locked modes

Shiraki, Daisuke; Paz-Soldan, Carlos; Hanson, Jeremy M.; La Haye, Robert J.; Logan, Nikolas C.; Olofsson, K. E. J.; Strait, Edward J.; Sweeney, Ryan M.; Volpe, Francesco A.

doi:10.1088/0741-3335/57/2/025016

Measurements of the toroidal torque balance of error field penetration locked modes

Journal Article · Sun Jan 04 23:00:00 EST 2015 · Plasma Physics and Controlled Fusion

DOI:https://doi.org/10.1088/0741-3335/57/2/025016· OSTI ID:1367534

Shiraki, Daisuke ^[1]; Paz-Soldan, Carlos ^[2]; Hanson, Jeremy M. ^[3]; La Haye, Robert J. ^[4]; Logan, Nikolas C. ^[5]; Olofsson, K. E. J. ^[3]; Strait, Edward J. ^[4]; Sweeney, Ryan M. ^[3]; Volpe, Francesco A. ^[3]

Columbia Univ., New York, NY (United States); General Atomics
Oak Ridge Institute for Science and Education, Oak Ridge, TN (United States)
Columbia Univ., New York, NY (United States)
General Atomics, San Diego, CA (United States)
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Here, detailed measurements from the DIII-D tokamak of the toroidal dynamics of error field penetration locked modes under the influence of slowly evolving external fields, enable study of the toroidal torques on the mode, including interaction with the intrinsic error field. The error field in these low density Ohmic discharges is well known based on the mode penetration threshold, allowing resonant and non-resonant torque effects to be distinguished. These m/n = 2/1 locked modes are found to be well described by a toroidal torque balance between the resonant interaction with n = 1 error fields, and a viscous torque in the electron diamagnetic drift direction which is observed to scale as the square of the perturbed field due to the island. Fitting to this empirical torque balance allows a time-resolved measurement of the intrinsic error field of the device, providing evidence for a time-dependent error field in DIII-D due to ramping of the Ohmic coil current.

View Accepted Manuscript (DOE)

Research Organization:: General Atomics, San Diego, CA (United States)

Sponsoring Organization:: USDOE

Grant/Contract Number:: FC02-04ER54698; SC0008520; AC05-06OR23100; AC02-09CH11466

OSTI ID:: 1367534

Alternate ID(s):: OSTI ID: 22362657

Journal Information:: Plasma Physics and Controlled Fusion, Journal Name: Plasma Physics and Controlled Fusion Journal Issue: 2 Vol. 57; ISSN 0741-3335

Publisher:: IOP ScienceCopyright Statement

Country of Publication:: United States

Language:: English

References (21)

A method to measure poloidal field coil irregularities in toroidal plasma devices La Haye, R. J.; Scoville, J. T. Review of Scientific Instruments, Vol. 62, Issue 9 https://doi.org/10.1063/1.1142330	journal	September 1991
Study of a low β classical tearing mode in DIII-D Chu, M. S.; La Haye, R. J.; Austin, M. E. Physics of Plasmas, Vol. 9, Issue 11 https://doi.org/10.1063/1.1510666	journal	November 2002
Nonaxisymmetric field effects on Alcator C-Mod Wolfe, S. M.; Hutchinson, I. H.; Granetz, R. S. Physics of Plasmas, Vol. 12, Issue 5 https://doi.org/10.1063/1.1883665	journal	May 2005
Advanced techniques for neoclassical tearing mode control in DIII-D Volpe, F. A. G.; Austin, M. E.; La Haye, R. J. Physics of Plasmas, Vol. 16, Issue 10 https://doi.org/10.1063/1.3232325	journal	October 2009
The importance of matched poloidal spectra to error field correction in DIII-D Paz-Soldan, C.; Lanctot, M. J.; Logan, N. C. Physics of Plasmas, Vol. 21, Issue 7 https://doi.org/10.1063/1.4886795	journal	July 2014
Critical error fields for locked mode instability in tokamaks La Haye, R. J.; Fitzpatrick, R.; Hender, T. C. Physics of Fluids B: Plasma Physics, Vol. 4, Issue 7 https://doi.org/10.1063/1.860017	journal	March 1992
Bifurcated states of a rotating tokamak plasma in the presence of a static error-field Fitzpatrick, Richard Physics of Plasmas, Vol. 5, Issue 9 https://doi.org/10.1063/1.873000	journal	September 1998
Locked modes in DIII-D and a method for prevention of the low density mode Scoville, J. T.; La Haye, R. J.; Kellman, A. G. Nuclear Fusion, Vol. 31, Issue 5 https://doi.org/10.1088/0029-5515/31/5/006	journal	May 1991
Effect of resonant magnetic perturbations on COMPASS-C tokamak discharges Hender, T. C.; Fitzpatrick, R.; Morris, A. W. Nuclear Fusion, Vol. 32, Issue 12 https://doi.org/10.1088/0029-5515/32/12/I02	journal	December 1992
Interaction of tearing modes with external structures in cylindrical geometry (plasma) Fitzpatrick, R. Nuclear Fusion, Vol. 33, Issue 7 https://doi.org/10.1088/0029-5515/33/7/I08	journal	July 1993
Field error instabilities in JET Fishpool, G. M.; Haynes, P. S. Nuclear Fusion, Vol. 34, Issue 1 https://doi.org/10.1088/0029-5515/34/1/I08	journal	January 1994
Error field mode studies on JET, COMPASS-D and DIII-D, and implications for ITER Buttery, R. J.; Benedetti, M. De'; Gates, D. A. Nuclear Fusion, Vol. 39, Issue 11Y https://doi.org/10.1088/0029-5515/39/11Y/323	journal	November 1999
Error field experiments in JET Buttery, R. J.; Benedetti, M. De'; Hender, T. C. Nuclear Fusion, Vol. 40, Issue 4 https://doi.org/10.1088/0029-5515/40/4/306	journal	April 2000
Multi-mode error field correction on the DIII-D tokamak Scoville, J. T.; Haye, R. J. La Nuclear Fusion, Vol. 43, Issue 4 https://doi.org/10.1088/0029-5515/43/4/305	journal	March 2003
Error field detection in DIII-D by magnetic steering of locked modes Shiraki, D.; La Haye, R. J.; Logan, N. C. Nuclear Fusion, Vol. 54, Issue 3 https://doi.org/10.1088/0029-5515/54/3/033006	journal	February 2014
Measurement of tokamak error fields using plasma response and its applicability to ITER Strait, E. J.; Buttery, R. J.; Casper, T. A. Nuclear Fusion, Vol. 54, Issue 7 https://doi.org/10.1088/0029-5515/54/7/073004	journal	April 2014
The spectral basis of optimal error field correction on DIII-D Paz-Soldan, C.; Buttery, R. J.; Garofalo, A. M. Nuclear Fusion, Vol. 54, Issue 7 https://doi.org/10.1088/0029-5515/54/7/073013	journal	April 2014
Nonlinear error-field penetration in low density ohmically heated tokamak plasmas Fitzpatrick, R. Plasma Physics and Controlled Fusion, Vol. 54, Issue 9 https://doi.org/10.1088/0741-3335/54/9/094002	journal	August 2012
Effect of Neoclassical Toroidal Viscosity on Error-Field Penetration Thresholds in Tokamak Plasmas Cole, A. J.; Hegna, C. C.; Callen, J. D. Physical Review Letters, Vol. 99, Issue 6 https://doi.org/10.1103/PhysRevLett.99.065001	journal	August 2007
Control of Nonaxisymmetric Magnetic Field Perturbations in Tokamaks Boozer, Allen H. Fusion Science and Technology, Vol. 59, Issue 3 https://doi.org/10.13182/FST11-A11697	journal	April 2011
Error Field Tolerance and Error Field Correction Strategies and Their Applicability to ITER Reimerdes, H.; Buttery, R. J.; Garofalo, A. M. Fusion Science and Technology, Vol. 59, Issue 3 https://doi.org/10.13182/FST11-A11698	journal	April 2011

Cited By (3)

Toroidal modeling of the n = 1 intrinsic error field correction experiments in EAST Yang, Xu; Liu, Yueqiang; Sun, Youwen Plasma Physics and Controlled Fusion, Vol. 60, Issue 5 https://doi.org/10.1088/1361-6587/aab30f	journal	March 2018
Simultaneous iterative learning control of mode entrainment and error field Choi, W.; Volpe, F. A. Nuclear Fusion, Vol. 59, Issue 5 https://doi.org/10.1088/1741-4326/ab0753	journal	March 2019
Simultaneous iterative learning control of mode entrainment and error field Choi, Wilkie; Volpe, Francesco arXiv https://doi.org/10.48550/arxiv.1812.05028	text	January 2018

Similar Records

Error field detection in DIII-D by magnetic steering of locked modes

Journal Article · Wed Feb 19 23:00:00 EST 2014 · Nuclear Fusion · OSTI ID:1352308

Neoclassical toroidal viscosity and error-field penetration in tokamaks

Journal Article · Thu May 15 00:00:00 EDT 2008 · Physics of Plasmas · OSTI ID:21120357

Effect of Neoclassical Toroidal Viscosity on Error-Field Penetration Thresholds in Tokamak Plasmas

Journal Article · Fri Aug 10 00:00:00 EDT 2007 · Physical Review Letters · OSTI ID:20957940

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
error field
locked mode
tokamak
torque balance

Measurements of the toroidal torque balance of error field penetration locked modes

Citation Formats

References (21)

Cited By (3)

Similar Records

Related Subjects