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arXiv · 0908.0378

Simulating Supersonic Turbulence in Magnetized Molecular Clouds

Alexei G. Kritsuk·Sergey D. Ustyugov·Michael L. Norman·Paolo Padoan
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Abstract

We present results of large-scale three-dimensional simulations of weakly magnetized supersonic turbulence at grid resolutions up to 1024^3 cells. Our numerical experiments are carried out with the Piecewise Parabolic Method on a Local Stencil and assume an isothermal equation of state. The turbulence is driven by a large-scale isotropic solenoidal force in a periodic computational domain and fully develops in a few flow crossing times. We then evolve the flow for a number of flow crossing times and analyze various statistical properties of the saturated turbulent state. We show that the energy transfer rate in the inertial range of scales is surprisingly close to a constant, indicating that Kolmogorov's phenomenology for incompressible turbulence can be extended to magnetized supersonic flows. We also discuss numerical dissipation effects and convergence of different turbulence diagnostics as grid resolution refines from 256^3 to 1024^3 cells.

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Alexei G. Kritsuk, Sergey D. Ustyugov, Michael L. Norman, Paolo Padoan. 2009-08-04. Simulating Supersonic Turbulence in Magnetized Molecular Clouds. https://doi.org/10.1088/1742-6596/180/1/012020

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