2026-04-13T02:47:41Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1938672025-12-04T20:47:11Zcom_2072_1057col_2072_478822col_2072_478914col_2072_478917

urn:hdl:2445/193867 Hydrodynamic and geometric effects in the sedimentation of model run-and-tumble microswimmers Scagliarini, Andrea Pagonabarraga Mora, Ignacio Hidrodinàmica Microorganismes Matèria condensada tova Hydrodynamics Microorganisms Soft condensed matter The sedimentation process in an active suspension is the result of the competition between gravity and the autonomous motion of particles. We carry out simulations of run-and-tumble squirmers that move in a fluid medium, focusing on the dependence of the non-equilibrium steady state on the swimming properties. We find that for large enough activity, the density profiles are no longer simple exponentials; we recover the numerical results through the introduction of a local effective temperature, suggesting that the breakdown of the Perrin-like exponential form is a collective effect due to fluid-mediated dynamic correlations among particles. We show that analogous concepts can also fit the case of active non-motile particles, for which we report the first study of this kind. Moreover, we provide evidence of scenarios where the solvent hydrodynamics induces non-local effects which require the full three-dimensional dynamics to be taken into account in order to understand sedimentation in active suspensions. Finally, analyzing the statistics of the orientations of microswimmers, the emergence of a height-dependent polar order in the system is discussed. 2023-02-20T16:05:06Z 2023-02-20T16:05:06Z 2022-06-06 2023-02-20T16:05:06Z info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Reproducció del document publicat a: https://doi.org/10.1039/D1SM01594J Soft Matter, 2022, vol. 18, p. 2407-2413 https://doi.org/10.1039/D1SM01594J cc-by (c) Scagliarini, Andrea et al., 2022 http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Royal Society of Chemistry Articles publicats en revistes (Física de la Matèria Condensada)