NUMERICAL MHD MODEL OF MAGNETOSHEATH
The interaction of the supersonic solar wind with the Earth's
magnetosphere forms the bow shock and a layer between the bow shock and the magnetopause
called the magnetosheath. A numerical non-stationary
three-dimensional MHD model of the magnetosheath has been developed beginning from 1996.
A few problems have been studied with this model.
1) It is well known from observations that T_(perpendicular to magnetic field) is larger than T_(parallel)
in the magnetosheath. We used equations derived from the bounded anisotropy model (Denton et al., JGR, 1994)
in order to calculate all MHD parameters and the ratio T_perp/T_parallel in the
magnetosheath. The obtained results well agree with spacecraft data.
2) Solar wind data are used as input parameters of the model.
Results of simulations have been compared with spacecraft
magnetosheath crossings. It has been found that
the MHD model can predict well observed
temporal/spatial variations in most cases. Observations of Song et al. (1990,1993,1994)
interpreted previously as a standing slow shock have been revisited.
Our results show that these observations
in the magnetosheath can be explained by temporal variations of the magnetic field and density in the solar wind.
3) It has been studied the influence of the magnetopause magnetic reconnection on
stationary magnetosheath flow. The maximum |B| in the magnetic barrier is found to be smaller
in a southward IMF case than in a northward case.
4) Interaction of an interplanetary shock (IS) with the Earth's magnetosphere has been studied.
In particular, we simulate the interaction of IS with the bow shock and study propagation of MHD discontinuities
through the magnetosheath. Using results of global MHD modeling obtained from
CCMC GSFC , we study variations in the
magnetosphere.
Simulating the magnetosheath flow, we use the TVD Lax-Friedrichs II-order numerical scheme.
The numerical region consists of the spherical and parabolic parts (the magnetopause is a paraboloid of revolution).
You can find much more information about my work in my publications.
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