A Two-Fluid Method for Ambipolar Diffusion

Abstract

We present a semi-implicit method for isothermal two-fluid ion-neutral ambipolar drift that is second-order accurate in space and time. The method has been implemented in the RIEMANN code for astrophysical fluid dynamics. We present four test problems that show the method works and correctly tracks the propagation of MHD waves and the structure of two-fluid C-shocks. The accurate propagation of MHD waves in the two-fluid approximation is shown to be a stringent test of the algorithm. We demonstrate that highly accurate methods are required in order to properly capture the MHD wave behaviour in the presence of ion-neutral friction.

29 pages, 16 figures, accepted to MNRAS

References in corpus (17)

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Cited by in corpus (13)

• Effect of Ambipolar Diffusion on the Non-linear Evolution of Magnetorotational Instability in Weakly Ionized Disks
• Incorporating Ambipolar and Ohmic Diffusion in the AMR MHD code RAMSES
• Damping of MHD turbulence in partially ionized plasma: implications for cosmic ray propagation
• Dust Settling in Magnetorotationally-Driven Turbulent Discs I: Numerical Methods and Evidence for a Vigorous Streaming Instability
• Alfvenic Turbulence Beyond the Ambipolar Diffusion Scale
• An Explicit Scheme for Incorporating Ambipolar Diffusion in a Magnetohydrodynamics Code
• The effect of ambipolar diffusion on low-density molecular ISM filaments
• Direct Evidence for Two-Fluid Effects in Molecular Clouds
• Sub-Alfvenic Non-Ideal MHD Turbulence Simulations with Ambipolar Diffusion: III. Implications for Observations and Turbulent Enhancement
• Observational Diagnostics for Two-Fluid Turbulence in Molecular Clouds As Suggested by Simulations
• Turbulent dynamo in a weakly ionized medium
• An Implicit Scheme for Ohmic Dissipation with Adaptive Mesh Refinement
• Numerical Methods for Simulating Star Formation