Destabilization of magnetohydrodynamic modes with finite Larmor radius effects in tandem mirrors

Journal Article · Wed Oct 01 04:00:00 EDT 1986 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.865852· OSTI ID:5137839

Kotschenreuther, M; Berk, H L

Difficulties in the stabilization of ideal magnetohydrodynamic (MHD) ballooning modes by finite Larmor radius (FLR) effects are considered, in tandem mirror geometry for azimuthal mode numbers l>1. A kinetic formalism is used to obtain corrections to the long, thin approximation, when keeping terms of quadratic order in the curvature. If eta/sub i/ -- partial ln T/sub i/ /partial ln n/sub i/ > or =0, with T/sub i/, n/sub i/, the ion temperature and density, ion resonance effects eliminate absolute FLR stability, though the residual growth rates are substantially reduced from the MHD values. However, the residual modes are still important, and mixing length estimates of the confinement degradation from modes with l>l indicate they can still severely limit the achievement of reactor-grade operation near and above the threshold beta values predicted from the ideal MHD theory. This is most severe if the ion temperature decreases radially (n/sub i/>0), whereupon significant instabilities can even arise below the ideal threshold. However, if -2/3

• Research Organization: Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712-1060
• OSTI ID: 5137839
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 29:10; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107* -- Fusion Energy-- Plasma Research-- Instabilities
AZIMUTH
BALLOONING INSTABILITY
DESIGN
DISPERSION RELATIONS
EQUATIONS
FLUID MECHANICS
HYDRODYNAMICS
INSTABILITY
KINETIC EQUATIONS
LARMOR RADIUS
MAGNETIC MIRRORS
MAGNETOHYDRODYNAMICS
MECHANICS
OPEN PLASMA DEVICES
PLASMA
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
STABILIZATION
TANDEM MIRRORS
THERMONUCLEAR DEVICES