Universal interchange instability in partially ionized gases

Journal Article · Wed Oct 31 23:00:00 EST 1990 · Physics of Fluids B; (USA)

DOI:https://doi.org/10.1063/1.859378· OSTI ID:6314305

Huba, J D ^[1]

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1. Space Plasma Branch, Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375-5000 (USA)

A magnetized, inhomogeneous, partially ionized gas is theoretically shown to be unstable to an interchange instability. The source of free energy for the instability is the cross-field current. The instability is caused by neutral drag dynamics, and is therefore critically dependent upon charged particle--neutral collisions {nu}{sub {alpha}{ital n}}. The growth rate is largest in the strongly coupled regime, i.e., {omega}{much lt}{nu}{sub {ital in}}, {nu}{sub {ital ni}}, and is given by {gamma}{congruent}({epsilon}{ital m}{sub {ital e}}/{ital m}{sub {ital i}}){sup 1/2}(1+{epsilon}){sup {minus}1}{ital k}{sub {ital y}}{ital V}{sub {ital d}}, where {ital k}{sub {ital y}} is the wave number, {ital V}{sub {ital d}}=({ital cT}/{ital eB})({partial derivative} ln({ital n}{sub {ital i}0})/{partial derivative}{ital x}) is the diamagnetic drift velocity, {ital T}={ital T}{sub {ital e}}+{ital T}{sub {ital i}}, and {epsilon}={ital m}{sub {ital n}}{ital n}{sub {ital n}}/{ital m}{sub {ital i}}{ital n}{sub {ital i}} ({ital m} is the mass and {ital n} the density of the ions ({ital i}) and neutrals ({ital n})). The growth rate is a maximum when {epsilon}=1, which corresponds to {nu}{sub {ital in}}={nu}{sub {ital ni}}.

• OSTI ID: 6314305
• Journal Information: Physics of Fluids B; (USA), Journal Name: Physics of Fluids B; (USA) Vol. 2:11; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

640430* -- Fluid Physics-- Magnetohydrodynamics
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ATOM COLLISIONS
ATOMS
COLLISIONS
COUPLING
CROSSED FIELDS
DIAMAGNETISM
DRAG
ELECTRON DRIFT
ENERGY
FLUIDS
FLUTE INSTABILITY
FREE ENERGY
GASES
INHOMOGENEOUS PLASMA
INSTABILITY
INSTABILITY GROWTH RATES
ION COLLISIONS
ION DRIFT
ION-ATOM COLLISIONS
IONIZED GASES
MAGNETIC FIELDS
MAGNETISM
MAGNETIZATION
PHYSICAL PROPERTIES
PLASMA
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
THERMODYNAMIC PROPERTIES
WEAKLY IONIZED GASES