HR: 0800h
AN: SM41A-0311    [Abstracts]
TI: A Robust MHD Scheme in Space Weather Modeling: A Carbuncle-Free HLL-type Solver
AU: * Miyoshi, T
EM: miyoshi@sci.hiroshima-u.ac.jp
AF: Hiroshima University, 1-3-1 Kagamiyama, Higashi-hiroshima, 739-8526, Japan
AU: Kusano, K
EM: kusano@jamstec.go.jp
AF: The Earth Simulator Center, JAMSTEC, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, 236-0001, Japan
AB: In the space weather modeling, it is indispensable to numerically reproduce severe plasma environments accurately. Therefore, shock capturing solvers for MHD have been applied to space MHD simulations so far. However, it has been found that, at hypersonic shock waves, high-resolution shock capturing solvers cause multi- dimensional numerical instabilities like the carbuncle phenomenon in neutral fluid (HD). In this study, numerical tests of the numerical instabilities at hypersonic MHD shocks are performed adopting typical high-resolution shock capturing solvers for MHD. Moreover, a robust multi-state HLL-type solver for MHD that can suppress the numerical instabilities is newly proposed. Numerical tests show that the numerical instabilities are generated in the high-resolution solvers, the Roe and the HLLD solvers, even for MHD. On the other hand, we find that newly developed solver, named as HLLD^- solver, is free from the carbuncle instabilities. In addition, an application of the HLLD^- solver to magnetospheric MHD simulations will be also presented.
DE: 7811 Discontinuities (2109)
DE: 7833 Mathematical and numerical techniques (0500, 3200)
DE: 7836 MHD waves and instabilities (2149, 2752, 6050)
DE: 7900 SPACE WEATHER
DE: 7959 Models
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting