Sawtooth stabilization through island pressure enhancement

Journal Article · Sun Feb 01 04:00:00 EST 1987 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.866375· OSTI ID:7067443

Park, W; Monticello, D A; Chu, T K

Using the compressible resistive magnetohydrodynamic (MHD) equations in a finite aspect ratio cylinder, it is found that the m = 1 mode (the sawtooth oscillation) can saturate when the pressure inside the magnetic island is higher than that of the original core plasma. The saturation condition is of the form ..delta beta../sub p/approx. >8epsilon/sup -1//sub q//sub //sub = //sub 1/(1-q/sub 0/)/sup 2/. This saturation effect can be used to actively stabilize sawteeth by heating or raising the density in the island. This mechanism, together with a stabilizing toroidal effect, may also explain recent lower-hybrid wave-driven tokamak experiments where the saturation of sawteeth has been observed.

• Research Organization: Plasma Physics Laboratory, Princeton University, P. O. Box 451, Princeton, New Jersey 08544
• OSTI ID: 7067443
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 30:2; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107* -- Fusion Energy-- Plasma Research-- Instabilities
ASPECT RATIO
CLOSED PLASMA DEVICES
COMPRESSIBILITY
CYLINDERS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
FLUID MECHANICS
HEATING
HIGH-FREQUENCY HEATING
HYDRODYNAMICS
INSTABILITY
LOWER HYBRID HEATING
MAGNETIC FIELD CONFIGURATIONS
MAGNETIC ISLANDS
MAGNETOHYDRODYNAMICS
MECHANICAL PROPERTIES
MECHANICS
OSCILLATION MODES
PHYSICAL PROPERTIES
PLASMA
PLASMA HEATING
PLASMA INSTABILITY
PLASMA PRESSURE
SATURATION
STABILIZATION
THERMONUCLEAR DEVICES
TOKAMAK DEVICES