title: A 2D suspension of active agents: the role of fluid mediated interactions.
abstract: Taking into account both the Vicsek short-range ordering and the far-field hydrodynamic interactions mediated by the ambient fluid, we investigate the role of long-range interactions in the ordering phenomena in a quasi 2-dimensional active suspension. By studying the number fluctuations, the velocity correlation functions and cluster size distribution function, we show that depending on the number density of swimmers and the strength of noise, the hydrodynamic interactions can have significant effects in a suspension. For a fixed value of noise, at larger density of particles, long-range interactions enhance the particle pairing and cluster formation in the system.
authors.affiliation: Department of Physics, University of Zanjan, Zanjan 45371-38791, Iran.
authors.forename: Hojjat
authors.initials: H
authors.lastname: Behmadi
authors.forename: Zahra
authors.initials: Z
authors.lastname: Fazli
authors.forename: Ali
authors.initials: A
authors.lastname: Najafi