Neoclassical viscosity effects on resistive magnetohydrodynamic modes in toroidal geometry

Journal Article · Sat Feb 29 23:00:00 EST 1992 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.860264· OSTI ID:7233862

Yang, J G; Oh, Y H; Choi, D I ^[1]; Kim, J Y; Horton, W ^[2]

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1. Korea Advanced Institute of Science and Technology, Cheongyangni, P.O. Box 150, Seoul (Korea, Republic of)
2. Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States)

The flux-surface-averaged linearized resistive magnetohydrodynamic (MHD) boundary-layer equations including the compressibility, diamagnetic drift, and neoclassical viscosity terms are derived in toroidal geometry. These equations describe the resistive layer dynamics of resistive MHD modes over the collisionality regime between the banana plateau and the Pfirsch--Schlueter. From the resulting equations, the effects of neoclassical viscosity on the stability of the tearing and resistive ballooning modes are investigated numerically. Also, a study is given for the problem of how the neoclassical resistive MHD mode is generated as the collisionality is reduced. It is shown that the neoclassical viscosity terms give a significant destabilizing effect for the tearing and resistive ballooning modes. This destabilization comes mainly from the reduction of the stabilizing effect of the parallel ion sound compression by the ion neoclassical viscosity. In the banana-plateau collisionality limit, where the compressibility is negligible, the dispersion relations of the tearing and resistive ballooning modes reduce to the same form, with the threshold value of the driving force given by {Delta}{sub {ital c}}=0. On the other hand, with the finite neoclassical effect it is found that the neoclassical resistive MHD instability is generated in agreement with previous results. Furthermore, it is shown that this later instability can be generated in a wide range of the collisionality including near the Pfirsch--Schlueter regime as well as the banana-plateau regime, suggesting that this mode is a probable cause of anomalous transport.

• DOE Contract Number: FG05-80ET53088
• OSTI ID: 7233862
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 4:3; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700330 -- Plasma Kinetics
Transport
& Impurities-- (1992-)
700370* -- Plasma Fluid & MHD Properties-- (1992-)
ANNULAR SPACE
BALLOONING INSTABILITY
BANANA REGIME
BOUNDARY LAYERS
CLOSED CONFIGURATIONS
COLLISIONAL PLASMA
COMPRESSIBILITY
CONFIGURATION
DIAMAGNETISM
DISPERSION RELATIONS
FLUCTUATIONS
FLUID MECHANICS
HYDRODYNAMICS
INSTABILITY
LAYERS
MAGNETIC FIELD CONFIGURATIONS
MAGNETISM
MAGNETOHYDRODYNAMICS
MECHANICAL PROPERTIES
MECHANICS
NEOCLASSICAL TRANSPORT THEORY
PLASMA
PLASMA DRIFT
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
SPACE
STABILIZATION
TEARING INSTABILITY
TOROIDAL CONFIGURATION
TRANSPORT THEORY
TRAPPING
VARIATIONS
VISCOSITY