Simulating Supersonic Turbulence in Magnetized Molecular Clouds

TL;DR

This paper presents large-scale 3D simulations of weakly magnetized supersonic turbulence in molecular clouds, demonstrating that Kolmogorov's turbulence phenomenology extends to these complex flows and analyzing the effects of numerical resolution.

Contribution

It provides high-resolution simulations of magnetized supersonic turbulence, showing the applicability of Kolmogorov's theory and examining numerical dissipation effects.

Findings

Energy transfer rate is nearly constant across inertial scales.

Kolmogorov's phenomenology extends to magnetized supersonic turbulence.

Higher grid resolution improves diagnostic convergence.

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.