Active particles with desired orientation flowing through a bottleneck

PARISI, DANIEL R.; CRUZ HIDALGO, RAÚL; ZURIGUEL, IKER

Scientific Reports

Nature Publishing Group

Año: 2018 vol. 8

We report extensive numerical simulations of the ow of anisotropic self-propelled particles through a constriction. In particular, we explore the role of the particles? desired orientation with respect to the moving direction on the system owability. We observe that when particles propel along the direction of their long axis (longitudinal orientation) the ow-rate notably reduces compared with the case of propulsion along the short axis (transversal orientation). And this is so even when the e ective section (measured as the number of particles that are necessary to span the whole outlet) is larger for the case of longitudinal propulsion. This counterintuitive result is explained in terms of the formation of clogging structures at the outlet, which are revealed to have higher stability when the particles align along the long axis. This generic result might be applied to many di erent systems owing through bottlenecks such as microbial populations or di erent kind of cells. Indeed, it has already a straightforward connection with recent results of pedestrian (which self-propel transversally oriented) and mice or sheep (which self-propel longitudinally oriented).