Quenching of external kink modes by localized radio-frequency fields

Journal Article · Sat Apr 01 04:00:00 EST 1989 · Phys Fluids B; (United States)

DOI:https://doi.org/10.1063/1.859005· OSTI ID:6202009

D'Ippolito, D A; Goedbloed, J P

The quenching of external kink modes by a spatially localized, externally applied surface force is studied in a low-beta cylindrical tokamak model. It is shown that m = 2 modes may be stabilized by the application of a radio frequency (rf) field in the ion cyclotron range of frequencies (ICRF) excited by either a toroidal or a poloidal antenna structure surrounding the plasma. Whereas linear mode coupling induced by toroidal localization is negligible, that caused by poloidal localization may degrade the stabilization and, thus, require increased power levels for stability. The model is directly applicable to the ponderomotive force exerted by an evanescent slow wave in the ion cyclotron range of frequencies. Quantitative estimates are made for ponderomotive stabilization of kink modes by means of ion-Bernstein-wave (IBW) antennas. This method of stabilization has the advantage that the antenna system does not have to match the spatial or temporal structure of the unstable modes. For typical IBW antenna systems, it is found that the required rf fields for kink stabilization are reasonable if the current profile is not too flat.

• Research Organization: Lodestar Research Corporation, 2400 Central Avenue, Boulder, Colorado 80301
• OSTI ID: 6202009
• Journal Information: Phys Fluids B; (United States), Journal Name: Phys Fluids B; (United States) Vol. 1:4; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107* -- Fusion Energy-- Plasma Research-- Instabilities
700108 -- Fusion Energy-- Plasma Research-- Wave Phenomena
CLOSED PLASMA DEVICES
CONFIGURATION
COUPLING
CYLINDRICAL CONFIGURATION
ELECTROMAGNETIC FIELDS
ELECTROMAGNETIC RADIATION
INHIBITION
INSTABILITY
KINK INSTABILITY
LOW-BETA PLASMA
OSCILLATION MODES
PLASMA
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
RADIATIONS
RADIOWAVE RADIATION
STABILIZATION
THERMONUCLEAR DEVICES
TOKAMAK DEVICES