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arXiv · 1206.2570

Clustering of gyrotactic microorganisms in turbulent flows

Filippo De Lillo·Guido Boffetta·Massimo Cencini
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Abstract

We study the spatial distribution of gyrotactic microorganisms transported by a three-dimensional turbulent flow generated by direct numerical simulations. We find that gyrotaxis combines with turbulent fluctuations to produce small scales (multi-)fractal clustering. We explain this result by showing that gyrotactic swimming cells behave like tracers in a compressible flow. The effective compressibility is derived in the limits of fluid acceleration much larger and smaller than the gravity.

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Filippo De Lillo, Guido Boffetta, Massimo Cencini. 2012-06-12. Clustering of gyrotactic microorganisms in turbulent flows. https://arxiv.org/abs/1206.2570

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