A STABLE, ACCURATE METHODOLOGY FOR HIGH MACH NUMBER, STRONG MAGNETIC FIELD MHD TURBULENCE WITH ADAPTIVE MESH REFINEMENT: RESOLUTION AND REFINEMENT STUDIES

作者：Li Pak Shing^*; Martin Daniel F; Klein Richard I; McKee Christopher F

来源：Astrophysical Journal, 2012, 745(2): 139.

DOI：10.1088/0004-637X/745/2/139

• ISM: kinematics and dynamics
• ISM: magnetic fields
• magnetic fields
• magnetohydrodynamics (MHD)
• methods: numerical
• stars: formation
• turbulence

Performing a stable, long-duration simulation of driven MHD turbulence with a high thermal Mach number and a strong initial magnetic field is a challenge to high-order Godunov ideal MHD schemes because of the difficulty in guaranteeing positivity of the density and pressure. We have implemented a robust combination of reconstruction schemes, Riemann solvers, limiters, and constrained transport electromotive force averaging schemes that can meet this challenge, and using this strategy, we have developed a new adaptive mesh refinement (AMR) MHD module of the ORION2 code. We investigate the effects of AMR on several statistical properties of a turbulent ideal MHD system with a thermal Mach number of 10 and a plasma beta(0) of 0.1 as initial conditions; our code is shown to be stable for simulations with higher Mach numbers (M-rms = 17.3) and smaller plasma beta (beta(0) = 0.0067) as well. Our results show that the quality of the turbulence simulation is generally related to the volume-averaged refinement. Our AMR simulations show that the turbulent dissipation coefficient for supersonic MHD turbulence is about 0.5, in agreement with unigrid simulations.

• 出版日期2012-2-1