Simulation of Kelvin--Helmholtz instability at the magnetospheric boundary

Journal Article · Wed Apr 01 00:00:00 EST 1987 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA092iA04p03195· OSTI ID:6597145

Miura, A

A two--dimensional magnetohydrodynamic simulation of Kelvin--Helmholtz instability at the terrestrial magnetospheric boundary is performed by including gradients or plasma and magnetic field normal to the dayside low-latitude magnetospheric boundary. A magnetopause current layer is corrugated highly nonlinearly by the instability, and a plasma blob is formed by an interchange motion associated with the instability. The magnetosheath plasma flow momentum is diffused into the magnetosphere by the anomalous tangential (Reynolds plus Maxwell) stresses associated with the instability, and a wide velocity boundary layer is formed just inside the magnetopause current layer, while the thickness or the magnetopause current layer remains almost constant during the evolution or the instability. The convection voltage drop (integral of the convection electric field) across the velocity shear layer is amplified several times by the anomalous momentum transport associated with the instability. The anomalous momentum flux into the magnetosphere (tangential stress) reaches 0.6 to a few percent of the magnetosheath flow momentum flux, and this anomalous momentum flux into the magnetosphere is sufficient for accounting for the observed tailward momentum flux in the low-latitude boundary layer.

• Research Organization: Geophysics Research Laboratory, University of Tokyo, Japan
• OSTI ID: 6597145
• Journal Information: J. Geophys. Res.; (United States), Vol. 92:A4
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
MAGNETOSHEATH
HELMHOLTZ INSTABILITY
BOUNDARY LAYERS
CONVECTION
EARTH MAGNETOSPHERE
FLOW RATE
MAGNETOHYDRODYNAMICS
MAGNETOPAUSE
PLASMA
SIMULATION
STRESSES
VELOCITY
VISCOSITY
VOLTAGE DROP
EARTH ATMOSPHERE
ENERGY TRANSFER
FLUID MECHANICS
HEAT TRANSFER
HYDRODYNAMICS
INSTABILITY
LAYERS
MASS TRANSFER
MECHANICS
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
640201* - Atmospheric Physics- Auroral
Ionospheric
& Magetospheric Phenomena