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arXiv · 2212.11008

Flocking turbulence of microswimmers in confined domains

Leonardo Puggioni·Guido Boffetta·Stefano Musacchio
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Abstract

We extensively study the Toner-Tu-Swift-Hohenberg model of motile active matter by means of direct numerical simulations in a two-dimensional confined domain. By exploring the space of parameters of the model we investigate the emergence of a new state of active turbulence which occurs when the aligning interactions and the self-propulsion of the swimmers are strong. This regime of flocking turbulence is characterized by a population of few strong vortices, each surrounded by an island of coherent flocking motion. The energy spectrum of flocking turbulence displays a power-law scaling with an exponent which depends weakly on the model parameters. By increasing the confinement we observe that flocking turbulence becomes unstable: after a long transient, characterized by power-law distributed transition times, the system switches to the ordered state of a single giant vortex

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Leonardo Puggioni, Guido Boffetta, Stefano Musacchio. 2022-12-21. Flocking turbulence of microswimmers in confined domains. https://doi.org/10.1103/physreve.107.055107

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