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arXiv · 2409.18576

Self-sustained patchy turbulence in shear-thinning active fluids

Henning Reinken·Andreas M. Menzel
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Abstract

Bacterial suspensions and other active fluids are known to develop highly dynamical vortex states, denoted as active or mesoscale turbulence. We reveal the pronounced effect of non-Newtonian rheological conditions on these turbulent states, concentrating on shear thinning. A self-sustained heterogeneous state of coexisting turbulent and quiescent areas develops, which results in anomalous velocity statistics. The heterogeneous state emerges in a hysteretic transition when varying activity. We provide an extensive numerical analysis and observe features consistent with a directed percolation transition. Our results are important, for instance, when addressing active objects in biological media with complex rheological properties.

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Henning Reinken, Andreas M. Menzel. 2024-09-27. Self-sustained patchy turbulence in shear-thinning active fluids. https://doi.org/10.1038/s42005-025-02200-3

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