English

Confinement-induced Self-Pumping in 3D Active Fluids

Soft Condensed Matter 2021-08-17 v2 Materials Science Statistical Mechanics Adaptation and Self-Organizing Systems Fluid Dynamics

Abstract

Two dimensional active fluids display a transition from turbulent to coherent flow upon decreasing the size of the confining geometry. A recent experiment suggests that the behavior in three dimensions is remarkably different; emergent flows transition from turbulence to coherence upon \emph{increasing} the confinement height to match the width. Using a simple hydrodynamic model of a suspension of extensile rod-like units, we provide the theoretical explanation for this puzzling behavior. Furthermore, using extensive numerical simulations supported by theoretical arguments, we map out the conditions that lead to coherent flows and elucidate the critical role played by the aspect ratio of the confining channel. The mechanism that we identify applies to a large class of symmetries and propulsion mechanisms, leading to a unified set of design principles for self-pumping 3D active fluids.

Keywords

Cite

@article{arxiv.2007.09277,
  title  = {Confinement-induced Self-Pumping in 3D Active Fluids},
  author = {Minu Varghese and Arvind Baskaran and Michael Hagan and Aparna Baskaran},
  journal= {arXiv preprint arXiv:2007.09277},
  year   = {2021}
}
R2 v1 2026-06-23T17:12:36.400Z