J.D. King E.J. Strait N.M. Ferraro J.M. Hanson S.R. Haskey M.J. Lanctot Y.Q. Liu N.Logan C. Paz-Soldan D. Shiraki A.D. Turnbull
Detailed measurements of the plasmas response to applied magnetic perturbations provide experimental evidence that the form of three-dimensional (3D) tokamak equilibria, with toroidal mode number n = 1, is determined by multiple stable kink modes at high-pressure. For pressures greater than the ideal magnetohydrodynamic (MHD) stability limit, as …
Preprint PublishedA. D. Turnbull N. M. Ferraro V. A. Izzo E. A. Lazarus J.-K. Park W. A. Cooper S. P. Hirshman L. L. Lao M. J. Lanctot S. Lazerson Y. Q. Liu A. Reiman F. Turco
With the installation of non-axisymmetric coil systems on major tokamaks for the purpose of studying the prospects of ELM-free operation, understanding the plasma response to the applied fields is a crucial issue. Application of different response models, using standard tools, to DIII-D discharges with applied non-axisymmetric fields from internal …
PublishedM. Okabayashi G. Matsunaga J.S. Degrassie W.W. Heidbrink Y. In Y.Q. Liu H. Reimerdes W.M. Solomon E.J. Strait M. Takechi N. Asakura R.V. Budny G.L. Jackson J.M. Hanson R. J. La Haye M.J. Lanctot J. Manickam K. Shinohara Y.B. Zhu
An energetic-particle (EP)-driven “off-axis-fishbone-like mode (OFM)” often triggers a resistive wall mode (RWM) in JT-60U and DIII-D devices, preventing long-duration high-b N discharges. In these experiments, the EPs are energetic ions (70–85 keV) injected by neutral beams to produce high-pressure plasmas. EP-driven bursting events reduce t…
PublishedM.J. Lanctot H. Reimerdes A.M. Garofalo M.S. Chu J. M. Hanson Y.Q. Liu G.A. Navratil I.N. Bogatu Y. In G.L. Jackson R.J. La Haye M. Okayabashi J.-K. Park M.J. Schaffer O. Schmitz E.J. Strait A.D. Turnbull
A detailed experiment-theory comparison reveals that linear ideal MHD theory is in quantitative agreement with external magnetic and internal soft x-ray measurements of the plasma response to externally applied non-axisymmetric fields over a broad range of beta and rotation. This result represents a significant step toward the goal of advancing the…
PublishedYueqiang Liu M.S. Chu W.F. Guo F. Villone R. Albanese G. Ambrosino M. Baruzzo T. Bolzonella I.T. Chapman A.M. Garofalo C.G. Gimblett R.J. Hastie T.C. Hender G.L. Jackson R.J. La Haye M.J. Lanctot Y.K. In G. Machiori M. Okabayashi R. Pac
Two issues of the resistive wall mode (RWM) control code maturity are addressed: the inclusion of advanced mode damping physics beyond the ideal MHD description, and the possibility of taking into account the influence of 3D features of the conducting structures on the mode stability and control. Examples of formulations and computational results a…
PublishedM. J. Lanctot
The first quantitative comparison of linear ideal magnetohydrodynamic MHD theory with external magnetic measurements of the nonaxisymmetric plasma perturbation driven by external long-wavelength magnetic fields in high-temperature tokamak plasmas is presented. The comparison yields good within 20% agreement for plasma pressures up to 75% of the ide…
Published