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arXiv · 2206.09655

Giant vortex dynamics in confined active turbulence

L. Puggioni·G. Boffetta·S. Musacchio
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Abstract

We report the numerical evidence of a new state of active turbulence in confined domains. By means of extensive numerical simulations of the Toner-Tu-Swift-Hohenberg model for dense bacterial suspensions in circular geometry, we discover the formation a stable, ordered state in which the angular momentum symmetry is broken. This is achieved by self-organization of a turbulent-like flow into a single, giant vortex of the size of the domain. The giant vortex is surrounded by an annular region close to the boundary, characterized by small-scale, radial vorticity streaks. The average radial velocity profile of the vortex is found to be in agreement with a simple analytical prediction. We also provide an estimate of the temporal and spatial scales of a suitable experimental setup comparable with our numerical findings.

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L. Puggioni, G. Boffetta, S. Musacchio. 2022-06-20. Giant vortex dynamics in confined active turbulence. https://doi.org/10.1103/physreve.106.055103

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