Sub-Alfvenic plasma expansion

Journal Article · Fri Oct 01 04:00:00 EDT 1993 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.860825· OSTI ID:6241469

Ripin, B H; Huba, J D; McLean, E A; Manka, C K; Peyser, T; Burris, H R; Grun, J ^[1]

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1. Plasma Physics Division, Naval Research Laboratory, Washington D.C. 20375-5346 (United States)

A large ion Larmor radius plasma undergoes a particularly robust form of Rayleigh--Taylor instability when sub-Alfvenically expanding into a magnetic field. Results from an experimental study of this instability are reported and compared with theory, notably a magnetohydrodynamic (MHD) treatment that includes the Hall term, a generalized kinetic lower-hybrid drift theory, and with computer simulations. Many theoretical predictions are confirmed while several features remain unexplained. New and unusual features appear in the development of this instability. In the linear stage there is an onset criterion insensitive to the magnetic field, initial density clumping (versus interchange), linear growth rate much higher than in the classic'' MHD regime, and dominant instability wavelength of order of the plasma density scale length. In the nonlinear limit free-streaming flutes, apparent splitting (bifurcation) of flutes, curling of flutes in the electron cyclotron sense, and a highly asymmetric expansion are found. Also examined is the effect on the instability of the following: an ambient background plasma (that adds collisionality and raises the expansion speed/Alfven speed ratio), magnetic-field line tying, and expansion asymmetries (that promotes plasma cross-field jetting).

• OSTI ID: 6241469
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 5:10; ISSN 0899-8221; ISSN PFBPEI
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
EXPANSION
FLUID MECHANICS
HALL EFFECT
HYDRODYNAMICS
INSTABILITY
LARMOR RADIUS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MECHANICS
NUMERICAL SOLUTION
PLASMA EXPANSION
RAYLEIGH-TAYLOR INSTABILITY