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arXiv · 2107.07588

Turbulence-induced clustering in compressible active fluids

Vasco M. Worlitzer·Gil Ariel·Avraham Be'er·Holger Stark·Markus Bär·Sebastian Heidenreich
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Abstract

We study a novel phase of active polar fluids, which is characterized by the continuous creation and destruction of dense clusters due to self-sustained turbulence. This state arises due to the interplay of the self-advection of the aligned swimmers and their defect topology. The typical cluster size is determined by the characteristic vortex size. Our results are obtained by investigating a continuum model of compressible polar active fluids, which incorporates typical experimental observations in bacterial suspensions by assuming a non-monotone dependence of speed on density.

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Vasco M. Worlitzer, Gil Ariel, Avraham Be'er, Holger Stark, Markus Bär, Sebastian Heidenreich. 2021-07-15. Turbulence-induced clustering in compressible active fluids. https://doi.org/10.1039/d1sm01276b

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