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arXiv · 2402.15015

Turbulence unsteadiness drives extreme clustering

Florencia Zapata·Sofía Angriman·Amélie Ferran·Pablo J. Cobelli·Martin Obligado·Pablo D. Mininni
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Abstract

We show that the unsteadiness of turbulence has a drastic effect on turbulence parameters and in particle cluster formation. To this end we use direct numerical simulations of particle laden flows with a steady forcing that generates an unsteady large-scale flow. Particle clustering correlates with the instantaneous Taylor-based flow Reynolds number, and anti-correlates with its instantaneous turbulent energy dissipation constant. A dimensional argument for these correlations is presented. In natural flows, unsteadiness can result in extreme particle clustering, which is stronger than the clustering expected from averaged inertial turbulence effects.

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Florencia Zapata, Sofía Angriman, Amélie Ferran, Pablo J. Cobelli, Martin Obligado, Pablo D. Mininni. 2024-02-22. Turbulence unsteadiness drives extreme clustering. https://arxiv.org/abs/2402.15015

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