Drift wave vortices in nonuniform plasmas with sheared magnetic fields

Journal Article · Fri May 01 04:00:00 EDT 1992 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.860131· OSTI ID:7182420

Su, X N; Horton, W; Morrison, P J ^[1]

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1. Department of Physics and Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States)

Nonlinear coherent structures governed by the coupled drift wave--ion-acoustic mode equations in nonuniform plasmas with sheared magnetic fields are studied analytically and numerically. A solitary vortex equation that includes the effects of density and temperature gradients and magnetic shear is derived and analyzed. The analytic and numerical studies show that for a plasma in a sheared magnetic field, even without the temperature and drift velocity gradients, solitary vortex solutions are possible; however, these solutions are not exponentially localized due to the presence of a nonstructurally stable perturbative tail that connects to the core of the vortex. The new coherent vortex structures are dipolelike in their symmetry, but are not the modons of Larichev and Reznik. In the presence of a small temperature or drift velocity gradient, the new shear-induced dipole cannot survive and will separate into monopoles, like the case of the modon in a sheared drift velocity as studied in Su {ital et} {ital al}. (Phys. Fluids B {bold 3}, 921 (1991)). The solitary solutions are found from the nonlinear eigenvalue problem for the effective potential in a quasi-one-dimensional approximation. The numerical simulations are performed in two dimensions with the coupled vorticity and parallel mass flow equations.

• DOE Contract Number: FG05-80ET53088
• OSTI ID: 7182420
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 4:5; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
ELECTRON TEMPERATURE
INHOMOGENEOUS PLASMA
ION ACOUSTIC WAVES
ION WAVES
MAGNETIC FIELDS
MONOPOLES
PLASMA
PLASMA WAVES
QUASI PARTICLES
SOLITONS
TEMPERATURE GRADIENTS
VORTICES
WAVE PROPAGATION