Development of global simulation model of the Heliosphere

S. Kamei, A. Nakamizo, and T. Tanaka

Department of Earth and Planetary Sciences
Kyushu University, Fukuoka 812-8581, Japan

The Heliospheric structure ranging from the solar surface to the earth's orbit is reproduced from a time stationary self-consistent three-dimensional (3D) magnetohydrodynamic (MHD) simulation. The simulation model incorporates gravity, coriori and centrifugal forces into the momentum equation, and coronal heating and field-aligned thermal conduction into the energy equation. The numerical method to solve MHD equations employs the finite volume total variation diminishing (TVD) scheme with the control volume consists of hexagonal columns that are generated by multiply dividing a dodecahedron into triangles on inscribing concentric spheres. The heating term in the present model has its peak around few solar radius (Rs) and exponentially falls to zero at great distance from the solar surface. The absolute value of heating depends on the topology of the solar magnetic field so as to be in inverse proportion with the magnetic expansion factor. The results of simulation reproduce the plasma-exit structure on the solar surface, the high-temperature region in the corona, the open- and closed-magnetic-field structure in the corona, the fast and slow streams of the solar wind, and the sector structure in the Heliosphere.