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Recent Results on Interstellar Turbulence

Miguel A. de Avillez·Dieter Breitschwerdt
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Abstract

The statistical properties of interstellar turbulence are studied by means of three-dimensional high-resolution HD and MHD simulations of a SN-driven ISM. It is found that the longitudinal and transverse turbulent length scales have time averaged (over a period of 50 Myr) ratios of 0.5-0.6, almost similar to the one expected for isotropic homogeneous turbulence. The mean characteristic size of the larger eddies is found to be ~75 pc. Furthermore, the scalings of the structure functions measured in the simulated disk show unambiguous departure from the Kolmogorv (1941) model being consistent with the latest intermittency studies of supersonic turbulence (Politano & Pouquet 1995; Boldyrev 2002). Our results are independent of the resolution, indicating that convergence has been reached, and that the unresolved smaller dissipative scales do not feed back on the larger ones.

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Miguel A. de Avillez, Dieter Breitschwerdt. 2006-01-11. Recent Results on Interstellar Turbulence. https://doi.org/10.1142/9789812773067_0006

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