title: Three-dimensional model for the effective viscosity of bacterial suspensions.
abstract: We derive the effective viscosity of dilute suspensions of swimming bacteria from the microscopic details of the interaction of an elongated body with the background flow. An individual bacterium propels itself forward by rotating its flagella and reorients itself randomly by tumbling. Due to the bacterium's asymmetric shape, interactions with a prescribed generic (such as planar shear or straining) background flow cause the bacteria to preferentially align in directions in which self-propulsion produces a significant reduction in the effective viscosity, in agreement with recent experiments on suspensions of Bacillus subtilis.
authors.affiliation: Department of Mathematics, Penn State University, McAllister Bldg, University Park, Pennsylvania 16802, USA.
authors.forename: Brian M
authors.initials: BM
authors.lastname: Haines
authors.forename: Andrey
authors.initials: A
authors.lastname: Sokolov
authors.forename: Igor S
authors.initials: IS
authors.lastname: Aranson
authors.forename: Leonid
authors.initials: L
authors.lastname: Berlyand
authors.forename: Dmitry A
authors.initials: DA
authors.lastname: Karpeev
mesh_terms: D001419:Bacteria / Q000737:chemistry*; D008958:Models, Molecular; D012212:Rheology; D013535:Suspensions; D014783:Viscosity
chemical_list: D013535:Suspensions