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

This content will become publicly available on July 1, 2020

Title: Intrinsic flow and tearing mode rotation in the RFP during improved confinement

Abstract

We use charge exchange recombination spectroscopy to make the first localized measurements of impurity ion flow velocity profiles in the reversed field pinch. Measurements in improved confinement plasmas reveal an intrinsic flow profile that is peaked on axis and mostly parallel to the equilibrium magnetic field. The toroidal flow decreases in time at off-axis locations where tearing modes are resonant, giving rise to a highly sheared flow profile near the axis. The tearing mode phase velocity correlates strongly with toroidal flow near the resonant surface and weakly with flow in other locations, providing an opportunity to verify the commonly held assumption that the plasma and mode move together at the resonant surface. Mechanisms for the observed momentum loss during the improved confinement period are evaluated and it is found that eddy currents in the conducting shell caused by the rotation of the dominant tearing mode dominate over other losses.

Authors:
ORCiD logo [1]; ORCiD logo [1];  [1]; ORCiD logo [2];  [2];  [2]; ORCiD logo [2]; ORCiD logo [2];  [2]
  1. Wheaton College, Wheaton, IL (United States). Dept. of Physics
  2. Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics
Publication Date:
Research Org.:
Wheaton College, Wheaton, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
OSTI Identifier:
1560812
Alternate Identifier(s):
OSTI ID: 1544463
Grant/Contract Number:  
FC02-05ER54814
Resource Type:
Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 26; Journal Issue: 7; 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

Craig, D., Tan, E. H., Schott, B., Anderson, J. K., Boguski, J., Den Hartog, D. J., Nishizawa, T., Nornberg, M. D., and Xing, Z. A. Intrinsic flow and tearing mode rotation in the RFP during improved confinement. United States: N. p., 2019. Web. doi:10.1063/1.5095620.
Craig, D., Tan, E. H., Schott, B., Anderson, J. K., Boguski, J., Den Hartog, D. J., Nishizawa, T., Nornberg, M. D., & Xing, Z. A. Intrinsic flow and tearing mode rotation in the RFP during improved confinement. United States. doi:10.1063/1.5095620.
Craig, D., Tan, E. H., Schott, B., Anderson, J. K., Boguski, J., Den Hartog, D. J., Nishizawa, T., Nornberg, M. D., and Xing, Z. A. Mon . "Intrinsic flow and tearing mode rotation in the RFP during improved confinement". United States. doi:10.1063/1.5095620.
@article{osti_1560812,
title = {Intrinsic flow and tearing mode rotation in the RFP during improved confinement},
author = {Craig, D. and Tan, E. H. and Schott, B. and Anderson, J. K. and Boguski, J. and Den Hartog, D. J. and Nishizawa, T. and Nornberg, M. D. and Xing, Z. A.},
abstractNote = {We use charge exchange recombination spectroscopy to make the first localized measurements of impurity ion flow velocity profiles in the reversed field pinch. Measurements in improved confinement plasmas reveal an intrinsic flow profile that is peaked on axis and mostly parallel to the equilibrium magnetic field. The toroidal flow decreases in time at off-axis locations where tearing modes are resonant, giving rise to a highly sheared flow profile near the axis. The tearing mode phase velocity correlates strongly with toroidal flow near the resonant surface and weakly with flow in other locations, providing an opportunity to verify the commonly held assumption that the plasma and mode move together at the resonant surface. Mechanisms for the observed momentum loss during the improved confinement period are evaluated and it is found that eddy currents in the conducting shell caused by the rotation of the dominant tearing mode dominate over other losses.},
doi = {10.1063/1.5095620},
journal = {Physics of Plasmas},
number = 7,
volume = 26,
place = {United States},
year = {2019},
month = {7}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on July 1, 2020
Publisher's Version of Record

Save / Share:

Works referenced in this record:

3D magnetic fields and plasma rotation in RFX-mod tokamak plasmas
journal, September 2013


Flow measurements and modelling in helical RFX-mod equilibria
journal, November 2011


Particle transport and rotation damping due to stochastic magnetic field lines
journal, May 1992

  • Finn, John M.; Guzdar, Parvez N.; Chernikov, Alexander A.
  • Physics of Fluids B: Plasma Physics, Vol. 4, Issue 5
  • DOI: 10.1063/1.860123

Momentum transport from tearing modes with shear flow
journal, May 2008

  • Ebrahimi, F.; Mirnov, V. V.; Prager, S. C.
  • Physics of Plasmas, Vol. 15, Issue 5
  • DOI: 10.1063/1.2838247

Effect of flow damping on drift-tearing magnetic islands in tokamak plasmas
journal, July 2009

  • Fitzpatrick, R.; Waelbroeck, F. L.
  • Physics of Plasmas, Vol. 16, Issue 7
  • DOI: 10.1063/1.3191719

Fast flow phenomena in a toroidal plasma
journal, June 1995

  • Den Hartog, D. J.; Almagri, A. F.; Chapman, J. T.
  • Physics of Plasmas, Vol. 2, Issue 6
  • DOI: 10.1063/1.871250

High throughput spectrometer for fast localized Doppler measurements
journal, January 2007

  • Craig, D.; Den Hartog, D. J.; Ennis, D. A.
  • Review of Scientific Instruments, Vol. 78, Issue 1
  • DOI: 10.1063/1.2424450

Plasma flow in the outer region of the RFX reversed field pinch experiment
journal, November 1996


Absolute wavelength calibration of a Doppler spectrometer with a custom Fabry-Perot optical system
journal, July 2016

  • Baltzer, M. M.; Craig, D.; Den Hartog, D. J.
  • Review of Scientific Instruments, Vol. 87, Issue 11
  • DOI: 10.1063/1.4955491

Mode-locking phenomena in the TPE-RX reversed-field pinch plasma
journal, October 1999

  • Yagi, Yasuyuki; Koguchi, Haruhisa; Sakakita, Hajime
  • Physics of Plasmas, Vol. 6, Issue 10
  • DOI: 10.1063/1.873647

Local measurements of tearing mode flows and the magnetohydrodynamic dynamo in the Madison Symmetric Torus reversed-field pinch
journal, August 2010

  • Ennis, D. A.; Craig, D.; Gangadhara, S.
  • Physics of Plasmas, Vol. 17, Issue 8
  • DOI: 10.1063/1.3458667

Two-fluid and finite Larmor radius effects on helicity evolution in a plasma pinch
journal, March 2016

  • Sauppe, J. P.; Sovinec, C. R.
  • Physics of Plasmas, Vol. 23, Issue 3
  • DOI: 10.1063/1.4942761

Rotation and momentum transport in tokamaks and helical systems
journal, March 2014


Spontaneous mode rotation in RFX
journal, June 2005

  • Terranova, D.; Bolzonella, T.; Guo, S. C.
  • Plasma Physics and Controlled Fusion, Vol. 47, Issue 7
  • DOI: 10.1088/0741-3335/47/7/006

Behavior of Impurity Ion Velocities during the Pulsed Poloidal Current Drive in the Madison Symmetric Torus Reversed-Field Pinch
journal, May 2003

  • Sakakita, Hajime; Craig, Darren; Anderson, Jay K.
  • Japanese Journal of Applied Physics, Vol. 42, Issue Part 2, No. 5B
  • DOI: 10.1143/JJAP.42.L505

Modeling fast charge exchange recombination spectroscopy measurements from the Madison Symmetric Torus
journal, October 2006

  • Gangadhara, S.; Craig, D.; Ennis, D. A.
  • Review of Scientific Instruments, Vol. 77, Issue 10
  • DOI: 10.1063/1.2219412

The First Plasma Rotation Measurement in a Large Reversed-Field Pinch Device, TPE-RX
journal, March 2000

  • Sakakita, Hajime; Yagi, Yasuyuki; Hirano, Yoichi
  • Journal of the Physical Society of Japan, Vol. 69, Issue 3
  • DOI: 10.1143/JPSJ.69.635

Propagation of magnetic islands in the Er=0 frame of co-injected neutral beam driven discharges in the DIII-D tokamak
journal, September 2003

  • La Haye, R. J.; Petty, C. C.; Strait, E. J.
  • Physics of Plasmas, Vol. 10, Issue 9
  • DOI: 10.1063/1.1602452

RFX-mod: A multi-configuration fusion facility for three-dimensional physics studies
journal, May 2013

  • Piovesan, P.; Bonfiglio, D.; Auriemma, F.
  • Physics of Plasmas, Vol. 20, Issue 5
  • DOI: 10.1063/1.4806765

Flow damping due to stochastization of the magnetic field
journal, January 2015

  • Ida, K.; Yoshinuma, M.; Tsuchiya, H.
  • Nature Communications, Vol. 6, Issue 1
  • DOI: 10.1038/ncomms6816

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
  • DOI: 10.1063/1.873650

Kinetic Stress and Intrinsic Flow in a Toroidal Plasma
journal, February 2013


Equilibrium reconstruction in the Madison Symmetric Torus reversed field pinch
journal, December 2003


Toroidal charge exchange recombination spectroscopy measurements on MST
journal, October 2010

  • Magee, R. M.; Den Hartog, D. J.; Fiksel, G.
  • Review of Scientific Instruments, Vol. 81, Issue 10
  • DOI: 10.1063/1.3478665

Perturbed magnetic-field phase slip for tokamaks
journal, January 1980


Diagnostic application of magnetic islands rotation in JET
journal, June 2016


A diagnostic neutral beam system for the MST reversed-field pinch
journal, January 2001

  • Abdrashitov, G. F.; Davydenko, V. I.; Deichuli, P. P.
  • Review of Scientific Instruments, Vol. 72, Issue 1
  • DOI: 10.1063/1.1318249

Experimental observations of driven and intrinsic rotation in tokamak plasmas
journal, July 2016


Momentum Transport from Nonlinear Mode Coupling of Magnetic Fluctuations
journal, October 2000


The Madison Symmetric Torus
journal, January 1991

  • Dexter, R. N.; Kerst, D. W.; Lovell, T. W.
  • Fusion Technology, Vol. 19, Issue 1
  • DOI: 10.13182/FST91-A29322

Classical confinement and outward convection of impurity ions in the MST RFP
journal, May 2012

  • Kumar, S. T. A.; Den Hartog, D. J.; Mirnov, V. V.
  • Physics of Plasmas, Vol. 19, Issue 5
  • DOI: 10.1063/1.4718310

Heavy ion beam probe operation in time varying equilibria of improved confinement reversed field pinch discharges
journal, October 2010

  • Demers, D. R.; Chen, X.; Schoch, P. M.
  • Review of Scientific Instruments, Vol. 81, Issue 10
  • DOI: 10.1063/1.3479109

Toroidal and poloidal plasma rotation in the reversed field pinch RFX
journal, June 1998


Measurements of the momentum and current transport from tearing instability in the Madison Symmetric Torus reversed-field pinch
journal, May 2009

  • Kuritsyn, A.; Fiksel, G.; Almagri, A. F.
  • Physics of Plasmas, Vol. 16, Issue 5
  • DOI: 10.1063/1.3090325

Spatially Resolved Measurements of Ion Heating during Impulsive Reconnection in the Madison Symmetric Torus
journal, February 2007


Extended MHD modeling of tearing-driven magnetic relaxation
journal, May 2017

  • Sauppe, J. P.; Sovinec, C. R.
  • Physics of Plasmas, Vol. 24, Issue 5
  • DOI: 10.1063/1.4977540

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
  • DOI: 10.1063/1.1689353

Rutherford scattering diagnostic for the Madison symmetric torus reversed-field pinch
journal, January 2001

  • Reardon, J. C.; Fiksel, G.; Forest, C. B.
  • Review of Scientific Instruments, Vol. 72, Issue 1
  • DOI: 10.1063/1.1321737

Drift-tearing magnetic islands in tokamak plasmas
journal, January 2008

  • Fitzpatrick, R.; Waelbroeck, F. L.
  • Physics of Plasmas, Vol. 15, Issue 1
  • DOI: 10.1063/1.2829757

An overview of intrinsic torque and momentum transport bifurcations in toroidal plasmas
journal, September 2013


Anomalous particle transport and flow shear in the edge region of RFP’s
journal, March 2003


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
  • DOI: 10.1063/1.1319606

Analysis of phase locking of tearing modes in reversed field pinch plasmas
journal, February 2001

  • Zanca, P.; Martines, E.; Bolzonella, T.
  • Physics of Plasmas, Vol. 8, Issue 2
  • DOI: 10.1063/1.1339835

Plasma Potential Well and Velocity Shear Layer at the Edge of Reversed Field Pinch Plasmas
journal, December 1997


Dependence of Perpendicular Viscosity on Magnetic Fluctuations in a Stochastic Topology
journal, May 2018


High confinement plasmas in the Madison Symmetric Torus reversed-field pinch
journal, May 2002

  • Chapman, B. E.; Almagri, A. F.; Anderson, J. K.
  • Physics of Plasmas, Vol. 9, Issue 5
  • DOI: 10.1063/1.1456930

Asymmetric magnetic flux generation, m=1 activity, and edge phenomena on a reversed-field pinch
journal, January 1987

  • Howell, R. B.; Ingraham, J. C.; Wurden, G. A.
  • Physics of Fluids, Vol. 30, Issue 6
  • DOI: 10.1063/1.866198

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
  • DOI: 10.1063/1.873118

Plasma flow in the reversed field pinch STP-3(M)
journal, June 1987


Direct Measurement of a Toroidally Directed Zonal Flow in a Toroidal Plasma
journal, March 2019