Featured Researcher
UC Riverside: Nikolai Pogorelov
Global MHD-Boltzmann model of the outer heliosphere based on Monte Carlo simulations
My team (Igor Kryukov and Sergey Borovikov) and I used DataStar to perform numerical investigation of the solar wind interaction with the local interstellar medium. The model is based on the simultaneous solution of the 3D system of magnetohydrodynamic (MHD) equations for the plasma component and three systems of Euler equations describing the behavior of three substantially different populations of neutral hydrogen.
Although sophisticated fluid models of the neutral interstellar gas can qualitatively capture some aspects of the neutral-plasma interaction, a neutral population's large mean free path makes a completely accurate description possible only by a kinetic approach. The development of a fully kinetic model is especially desirable to describe the transport of different types of neutral particles into the heliosphere and to determine the properties of the Local Interstellar Cloud.
We also used DataStar to port Chombo AMR package and extend it to MHD problems. High resolution allowed us to discover the presence of both Rayleigh-Taylor and Kelvin-Helmholtz instability of the surface of the heliopause.
Figure 1: A cut of the 3D heliosphere by the solar ecliptic plane. The bow shock, the heliopause, and the termination shock are clearly seen. One spiral interplanetary magnetic field line is shown as well as interstellar magnetic field lines. The latter are chosen here to be perpendicular to the interstellar medium velocity, which is directed opposite to the z-axis.
Figure 2: The heliospheric interface.
