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arXiv · 2602.02299

Transition to dilatation-dominated isothermal compressible turbulence

Shadab Alam·Christoph Federrath·Jörg Schumacher
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Abstract

The kinetic energy dissipation rate is of central importance for small-scale statistics in turbulent flows. Here, we report a transition to the dilatation-dominated regime of three-dimensional isothermal fully compressible, homogeneous, isotropic turbulence by moments of energy dissipation and its components up to order~4 for root-mean-square (rms) Mach numbers $0.1\le M_{\rm rms}\le 10$ and for Reynolds numbers $100\le Re\le 2400$. Our high-resolution numerical simulations show a crossover from incompressible to $M_{\rm rms}$--independent, Burgers turbulence-like scaling of energy dissipation rate moments with respect to Reynolds number $Re$. This confirms the statistical dominance of shocks for rms Mach numbers $M_{\rm rms}\gtrsim 1$.

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Shadab Alam, Christoph Federrath, Jörg Schumacher. 2026-02-02. Transition to dilatation-dominated isothermal compressible turbulence. https://doi.org/10.1103/xtt8-k51b

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