Measurement and modeling of three-dimensional equilibria in DIII-D

Journal Article · Sun May 15 00:00:00 EDT 2011 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3593009· OSTI ID:21537884

Lanctot, M J; Reimerdes, H; Navratil, G A ^[1]; Garofalo, A M; Chu, M S; Jackson, G L; La Haye, R J; Schaffer, M J; Strait, E J; Turnbull, A D ^[2]; Hanson, J M ^[3]; Liu, Y Q ^[4]; Bogatu, I N; In, Y ^[5]; Okayabashi, M; Park, J -K ^[6]; Schmitz, O ^[7]

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1. Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States)
2. General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)
3. Oak Ridge Institute for Science and Education, P.O. Box 117, Oak Ridge, Tennessee 37831-0117 (United States)
4. EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom)
5. FAR-TECH, Inc., San Diego, California 92121 (United States)
6. Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543-0451 (United States)
7. Institut fur Energieforschung-Plasmaphysik, Forschungszentrum Julich GmbH, EURATOM Association, Trilateral Euregio Cluster, D-52425 Julich (Germany)

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 understanding of three-dimensional tokamak equilibria. Both the magnetic and soft x-ray measurements show the driven plasma perturbation increases linearly with the applied perturbation, suggesting the relevance of linear plasma response models. The magnetic and soft x-ray measurements are made at multiple toroidal and poloidal locations, allowing well resolved measurements of the global structure. The comparison also highlights the need to include kinetic effects in the MHD model once beta exceeds 80% of the kink mode limit without a conducting wall. Two distinct types of response fields are identified by the linear ideal MHD model: one that consists of localized currents at the rational surfaces that cancel the applied resonant field and another that is excited by the components of the external field that couple to the kink mode. Numerical simulations show these two fields have similar amplitudes in ITER-shaped DIII-D discharges where n = 3 fields are used to suppress edge localized modes.

• OSTI ID: 21537884
• Journal Information: Physics of Plasmas, Vol. 18, Issue 5; Other Information: DOI: 10.1063/1.3593009; (c) 2011 American Institute of Physics; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
COMPUTERIZED SIMULATION
DISTURBANCES
DOUBLET-3 DEVICE
EDGE LOCALIZED MODES
ELECTRIC DISCHARGES
EQUILIBRIUM
MAGNETOHYDRODYNAMICS
PLASMA
PLASMA DIAGNOSTICS
PLASMA SIMULATION
SOFT X RADIATION
THREE-DIMENSIONAL CALCULATIONS
CLOSED PLASMA DEVICES
ELECTROMAGNETIC RADIATION
FLUID MECHANICS
HYDRODYNAMICS
INSTABILITY
IONIZING RADIATIONS
MECHANICS
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
RADIATIONS
SIMULATION
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
X RADIATION