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arXiv · 2606.05788

Sub-Kolmogorov Intermittency and Multifractal Dissipation in Multiphase Turbulence

Marco Crialesi-Esposito·Alienor Riviere·Sergio Chibbaro
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Abstract

Multiphase turbulence displays stronger intermittency than its single-phase counterpart, yet the origin and geometrical organization of its most intense small-scale fluctuations remain poorly understood. Using direct numerical simulations of the incompressible Navier--Stokes equations with surface tension, we show that the local dissipative cutoff broadens strongly in the presence of interfaces, with dissipative events extending deep into the sub-Kolmogorov range. These events are spatially concentrated around topology-changing interfacial regions, namely breakup and coalescence. A multifractal analysis of the dissipation field further reveals that, while the spectrum above the Kolmogorov length, $\eta_K$, remains close to the single-phase case except for the most singular tail, the near- and sub-Kolmogorov range develops a markedly broader singularity spectrum supported on sparse intense structures. Our results show that breakup and coalescence do not simply perturb turbulence locally, but imprint a distinct multifractal organization on dissipation in multiphase turbulence.

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Marco Crialesi-Esposito, Alienor Riviere, Sergio Chibbaro. 2026-06-04. Sub-Kolmogorov Intermittency and Multifractal Dissipation in Multiphase Turbulence. https://arxiv.org/abs/2606.05788

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