English

Self-sustained patchy turbulence in shear-thinning active fluids

Soft Condensed Matter 2025-07-03 v2 Fluid Dynamics

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.

Keywords

Cite

@article{arxiv.2409.18576,
  title  = {Self-sustained patchy turbulence in shear-thinning active fluids},
  author = {Henning Reinken and Andreas M. Menzel},
  journal= {arXiv preprint arXiv:2409.18576},
  year   = {2025}
}
R2 v1 2026-06-28T18:59:15.800Z