Tearing mode dynamics and locking in the presence of external magnetic perturbations
Abstract
In normal operation, Madison Symmetric Torus (MST) [R. N. Dexter et al., Fusion Technol. 19, 131 (1991)] reversed-field pinch plasmas exhibit several rotating tearing modes (TMs). Application of a resonant magnetic perturbation (RMP) results in braking of mode rotation and, if the perturbation amplitude is sufficiently high, in a wall-locked state. The coils that produce the magnetic perturbation in MST give rise to RMPs with several toroidal harmonics. As a result, simultaneous deceleration of all modes is observed. In this paper, the measured TM dynamics is shown to be in qualitative agreement with a magnetohydrodynamical model of the RMP interaction with the TM [R. Fitzpatrick, Nucl. Fusion 33, 1049 (1993)] adapted to MST. To correctly model the TM dynamics, the electromagnetic torque acting on several TMs is included. Quantitative agreement of the TM slowing-down time was obtained for a kinematic viscosity in the order of m2/s. Analysis of discharges with different plasma densities shows an increase of the locking threshold with increasing density. Modeling results show good agreement with the experimental trend, assuming a density-independent kinematic viscosity. Finally, comparison of the viscosity estimates in this paper to those made previously with other techniques in MST plasmas suggests the possibility that the RMP technique may allow for estimates of the viscosity over a broad range of plasmas in MST and other devices.
- Authors:
-
[1];
[2];
[1];
[2];
[1];
- KTH Royal Inst. of Technology, Stockholm (Sweden). Dept. of Fusion Plasma Physics. School of Electrical Engineering
- Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics
- Publication Date:
- Research Org.:
- Univ. of Wisconsin, Madison, WI (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Fusion Energy Sciences (FES)
- OSTI Identifier:
- 1471533
- Alternate Identifier(s):
- OSTI ID: 1256537
- Grant/Contract Number:
- FC02-05ER54814
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Physics of Plasmas
- Additional Journal Information:
- Journal Volume: 23; Journal Issue: 6; 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; isotopes; plasma confinement; plasma density; magnetic ordering; tokamaks; plasma devices; wave mechanics; viscosity; plasma interactions; torque
Citation Formats
Fridström, R., Munaretto, S., Frassinetti, L., Chapman, B. E., Brunsell, P. R., and Sarff, J. S. Tearing mode dynamics and locking in the presence of external magnetic perturbations. United States: N. p., 2016.
Web. doi:10.1063/1.4953438.
Fridström, R., Munaretto, S., Frassinetti, L., Chapman, B. E., Brunsell, P. R., & Sarff, J. S. Tearing mode dynamics and locking in the presence of external magnetic perturbations. United States. https://doi.org/10.1063/1.4953438
Fridström, R., Munaretto, S., Frassinetti, L., Chapman, B. E., Brunsell, P. R., and Sarff, J. S. Fri .
"Tearing mode dynamics and locking in the presence of external magnetic perturbations". United States. https://doi.org/10.1063/1.4953438. https://www.osti.gov/servlets/purl/1471533.
@article{osti_1471533,
title = {Tearing mode dynamics and locking in the presence of external magnetic perturbations},
author = {Fridström, R. and Munaretto, S. and Frassinetti, L. and Chapman, B. E. and Brunsell, P. R. and Sarff, J. S.},
abstractNote = {In normal operation, Madison Symmetric Torus (MST) [R. N. Dexter et al., Fusion Technol. 19, 131 (1991)] reversed-field pinch plasmas exhibit several rotating tearing modes (TMs). Application of a resonant magnetic perturbation (RMP) results in braking of mode rotation and, if the perturbation amplitude is sufficiently high, in a wall-locked state. The coils that produce the magnetic perturbation in MST give rise to RMPs with several toroidal harmonics. As a result, simultaneous deceleration of all modes is observed. In this paper, the measured TM dynamics is shown to be in qualitative agreement with a magnetohydrodynamical model of the RMP interaction with the TM [R. Fitzpatrick, Nucl. Fusion 33, 1049 (1993)] adapted to MST. To correctly model the TM dynamics, the electromagnetic torque acting on several TMs is included. Quantitative agreement of the TM slowing-down time was obtained for a kinematic viscosity in the order of νkin≈10–20 m2/s. Analysis of discharges with different plasma densities shows an increase of the locking threshold with increasing density. Modeling results show good agreement with the experimental trend, assuming a density-independent kinematic viscosity. Finally, comparison of the viscosity estimates in this paper to those made previously with other techniques in MST plasmas suggests the possibility that the RMP technique may allow for estimates of the viscosity over a broad range of plasmas in MST and other devices.},
doi = {10.1063/1.4953438},
journal = {Physics of Plasmas},
number = 6,
volume = 23,
place = {United States},
year = {Fri Jun 10 00:00:00 EDT 2016},
month = {Fri Jun 10 00:00:00 EDT 2016}
}
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Works referenced in this record:
Mitigation of type-I ELMs with n = 2 fields on JET with ITER-like wall
journal, June 2013
- Liang, Y.; Lomas, P.; Nunes, I.
- Nuclear Fusion, Vol. 53, Issue 7
Field error instabilities in JET
journal, January 1994
- Fishpool, G. M.; Haynes, P. S.
- Nuclear Fusion, Vol. 34, Issue 1
Effect of resonant magnetic perturbations on COMPASS-C tokamak discharges
journal, December 1992
- Hender, T. C.; Fitzpatrick, R.; Morris, A. W.
- Nuclear Fusion, Vol. 32, Issue 12
Bifurcated states of a rotating tokamak plasma in the presence of a static error-field
journal, September 1998
- Fitzpatrick, Richard
- Physics of Plasmas, Vol. 5, Issue 9
Error field assessment from driven rotation of stable external kinks at EXTRAP-T2R reversed field pinch
journal, March 2013
- Volpe, F. A.; Frassinetti, L.; Brunsell, P. R.
- Nuclear Fusion, Vol. 53, Issue 4
Nonlinear tearing mode interactions and mode locking in reversed‐field pinches
journal, December 1996
- Hegna, C. C.
- Physics of Plasmas, Vol. 3, Issue 12
Nonlinear growth of the tearing mode
journal, January 1973
- Rutherford, P. H.
- Physics of Fluids, Vol. 16, Issue 11
Strong Flow Shear and Reduced Fluctuations in a Reversed-Field Pinch
journal, March 1998
- Chapman, B. E.; Chiang, C. -S.; Prager, S. C.
- Physical Review Letters, Vol. 80, Issue 10
The interaction between plasma rotation, stochastic fields and tearing mode excitation by external perturbation fields
journal, January 2008
- De Bock, M. F. M.; Classen, I. G. J.; Busch, C.
- Nuclear Fusion, Vol. 48, Issue 1
Mode locking phenomena observed near the stability boundary of the ideal interchange mode of LHD
journal, September 2012
- Takemura, Y.; Sakakibara, S.; Narushima, Y.
- Nuclear Fusion, Vol. 52, Issue 10
Plasma Angular-Momentum Loss by MHD Mode Locking
journal, April 1990
- Zohm, H.; Kallenbach, A.; Bruhns, H.
- Europhysics Letters (EPL), Vol. 11, Issue 8
Tearing mode velocity braking due to resonant magnetic perturbations
journal, September 2012
- Frassinetti, L.; Menmuir, S.; Olofsson, K. E. J.
- Nuclear Fusion, Vol. 52, Issue 10
Locked modes in DIII-D and a method for prevention of the low density mode
journal, May 1991
- Scoville, J. T.; La Haye, R. J.; Kellman, A. G.
- Nuclear Fusion, Vol. 31, Issue 5
Interaction of an external rotating magnetic field with the tearing mode in a plasma surrounded by a resistive wall
journal, July 2001
- Guo, S. C.; Chu, M. S.
- Physics of Plasmas, Vol. 8, Issue 7
RMP ELM suppression in DIII-D plasmas with ITER similar shapes and collisionalities
journal, January 2008
- Evans, T. E.; Fenstermacher, M. E.; Moyer, R. A.
- Nuclear Fusion, Vol. 48, Issue 2
Hydromagnetic stability of a diffuse linear pinch
journal, June 1960
- Newcomb, William A.
- Annals of Physics, Vol. 10, Issue 2
Reduced Edge Instability and Improved Confinement in the MST Reversed-Field Pinch
journal, October 2001
- Chapman, B. E.; Anderson, J. K.; Biewer, T. M.
- Physical Review Letters, Vol. 87, Issue 20
Effect of a resistive vacuum vessel on dynamo mode rotation in reversed field pinches
journal, October 1999
- Fitzpatrick, R.; Guo, S. C.; Den Hartog, D. J.
- Physics of Plasmas, Vol. 6, Issue 10
Nonlinear dynamo mode dynamics in reversed field pinches
journal, September 2000
- Fitzpatrick, Richard; Yu, Edmund P.
- Physics of Plasmas, Vol. 7, Issue 9
Effects of multiple resistive shells and transient electromagnetic torque on the dynamics of mode locking in reversed field pinch plasmas
journal, November 2002
- Guo, S. C.; Chu, M. S.
- Physics of Plasmas, Vol. 9, Issue 11
Neoclassical tearing modes and their control
journal, May 2006
- La Haye, R. J.
- Physics of Plasmas, Vol. 13, Issue 5
Error field detection in DIII-D by magnetic steering of locked modes
journal, February 2014
- Shiraki, D.; La Haye, R. J.; Logan, N. C.
- Nuclear Fusion, Vol. 54, Issue 3
Measurements of the toroidal torque balance of error field penetration locked modes
journal, January 2015
- Shiraki, D.; Paz-Soldan, C.; Hanson, J. M.
- Plasma Physics and Controlled Fusion, Vol. 57, Issue 2
Locking of multiple resonant mode structures in the reversed-field pinch
journal, August 1998
- Hansen, A. K.; Almagri, A. F.; Den Hartog, D. J.
- Physics of Plasmas, Vol. 5, Issue 8
Tearing modes transition from slow to fast rotation branch in the presence of magnetic feedback
journal, October 2014
- Innocente, P.; Zanca, P.; Zuin, M.
- Nuclear Fusion, Vol. 54, Issue 12
Control of tearing modes in toroidal fusion experiments using “designer” error fields
journal, June 2001
- Fitzpatrick, Richard; Rossi, Enrico
- Physics of Plasmas, Vol. 8, Issue 6
Non-resonant magnetic braking on JET and TEXTOR
journal, July 2012
- Sun, Y.; Liang, Y.; Shaing, K. C.
- Nuclear Fusion, Vol. 52, Issue 8
Control of 3D equilibria with resonant magnetic perturbations in MST
journal, September 2015
- Munaretto, S.; Chapman, B. E.; Holly, D. J.
- Plasma Physics and Controlled Fusion, Vol. 57, Issue 10
Statistical analysis of disruptions in JET
journal, April 2009
- de Vries, P. C.; Johnson, M. F.; Segui, I.
- Nuclear Fusion, Vol. 49, Issue 5
Nonlinear magnetohydrodynamics simulation using high-order finite elements
journal, March 2004
- Sovinec, C. R.; Glasser, A. H.; Gianakon, T. A.
- Journal of Computational Physics, Vol. 195, Issue 1
Hysteresis in the tearing mode locking/unlocking due to resonant magnetic perturbations in EXTRAP T2R
journal, September 2015
- Fridström, R.; Frassinetti, L.; Brunsell, P. R.
- Plasma Physics and Controlled Fusion, Vol. 57, Issue 10
Influence of externally applied magnetic perturbations on neoclassical tearing modes at ASDEX Upgrade
journal, December 2014
- Fietz, S.; Bergmann, A.; Classen, I.
- Nuclear Fusion, Vol. 55, Issue 1
Active control of type-I edge localized modes with n = 1 and n = 2 fields on JET
journal, January 2010
- Liang, Y.; Koslowski, H. R.; Thomas, P. R.
- Nuclear Fusion, Vol. 50, Issue 2
Momentum Transport from Nonlinear Mode Coupling of Magnetic Fluctuations
journal, October 2000
- Hansen, A. K.; Almagri, A. F.; Craig, D.
- Physical Review Letters, Vol. 85, Issue 16
Locked mode thresholds on the MAST spherical tokamak
journal, August 2007
- Howell, D. F.; Hender, T. C.; Cunningham, G.
- Nuclear Fusion, Vol. 47, Issue 9
Effect of externally applied resonant magnetic perturbations on resistive tearing modes
journal, July 2012
- Hu, Qiming; Yu, Q.; Rao, Bo
- Nuclear Fusion, Vol. 52, Issue 8
Observation of tearing mode deceleration and locking due to eddy currents induced in a conducting shell
journal, May 2004
- Chapman, B. E.; Fitzpatrick, R.; Craig, D.
- Physics of Plasmas, Vol. 11, Issue 5
Advanced techniques for neoclassical tearing mode control in DIII-D
journal, October 2009
- Volpe, F. A. G.; Austin, M. E.; La Haye, R. J.
- Physics of Plasmas, Vol. 16, Issue 10
First charge exchange recombination spectroscopy and motional Stark effect results from the Madison Symmetric Torus reversed field pinch
journal, January 2001
- Craig, D.; Den Hartog, D. J.; Fiksel, G.
- Review of Scientific Instruments, Vol. 72, Issue 1
Braking due to non-resonant magnetic perturbations and comparison with neoclassical toroidal viscosity torque in EXTRAP T2R
journal, September 2015
- Frassinetti, L.; Sun, Y.; Fridström, R.
- Nuclear Fusion, Vol. 55, Issue 11
Control of 3D edge radiation structure with resonant magnetic perturbation fields applied to the stochastic layer and stabilization of radiative divertor plasma in LHD
journal, September 2013
- Kobayashi, M.; Masuzaki, S.; Yamada, I.
- Nuclear Fusion, Vol. 53, Issue 9
Avoidance of tearing modes wall-locking in a reversed field pinch with active feedback coils
journal, December 2008
- Zanca, P.
- Plasma Physics and Controlled Fusion, Vol. 51, Issue 1
Resonant magnetic perturbation effect on tearing mode dynamics
journal, February 2010
- Frassinetti, L.; Olofsson, K. E. J.; Brunsell, P. R.
- Nuclear Fusion, Vol. 50, Issue 3
The tearing mode locking–unlocking mechanism to an external resonant field in EXTRAP T2R
journal, August 2014
- Frassinetti, L.; Fridström, R.; Menmuir, S.
- Plasma Physics and Controlled Fusion, Vol. 56, Issue 10
Error field mode studies on JET, COMPASS-D and DIII-D, and implications for ITER
journal, November 1999
- Buttery, R. J.; Benedetti, M. De'; Gates, D. A.
- Nuclear Fusion, Vol. 39, Issue 11Y
Magnetohydrodynamic-activity-induced toroidal momentum dissipation in collisionless regimes in tokamaks
journal, May 2003
- Shaing, K. C.
- Physics of Plasmas, Vol. 10, Issue 5
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
Interaction of tearing modes with external structures in cylindrical geometry (plasma)
journal, July 1993
- Fitzpatrick, R.
- Nuclear Fusion, Vol. 33, Issue 7
Mode locking in tokamaks
journal, December 1990
- Nave, M. F. F.; Wesson, J. A.
- Nuclear Fusion, Vol. 30, Issue 12
Improved evolution equations for magnetic island chains in toroidal pinch plasmas subject to externally applied resonant magnetic perturbations
journal, October 2001
- Fitzpatrick, Richard; Rossi, Enrico; Yu, Edmund P.
- Physics of Plasmas, Vol. 8, Issue 10
Feedback control of resistive wall modes in reversed field pinches
journal, August 2002
- Paccagnella, R.; Gregoratto, D.; Bondeson, A.
- Nuclear Fusion, Vol. 42, Issue 9
Semi-implicit magnetohydrodynamic calculations
journal, June 1987
- Schnack, D. D.; Barnes, D. C.; Mikic, Z.
- Journal of Computational Physics, Vol. 70, Issue 2
Momentum transport and flow damping in the reversed-field pinch plasma
journal, November 1998
- Almagri, A. F.; Chapman, J. T.; Chiang, C. S.
- Physics of Plasmas, Vol. 5, Issue 11
Rotation in a reversed field pinch with active feedback stabilization of resistive wall modes
journal, August 2006
- Cecconello, M.; Menmuir, S.; Brunsell, P. R.
- Plasma Physics and Controlled Fusion, Vol. 48, Issue 9
Suppression of Large Edge-Localized Modes in High-Confinement DIII-D Plasmas with a Stochastic Magnetic Boundary
journal, June 2004
- Evans, T. E.; Moyer, R. A.; Thomas, P. R.
- Physical Review Letters, Vol. 92, Issue 23
Active MHD control at high currents in RFX-mod
journal, July 2007
- Martini, S.; Agostini, M.; Alessi, C.
- Nuclear Fusion, Vol. 47, Issue 8