title: Nonlinear rheology of active particle suspensions: insights from an analytical approach.
abstract: We consider active suspensions in the isotropic phase subjected to a shear flow. Using a set of extended hydrodynamic equations we derive a variety of analytical expressions for rheological quantities such as shear viscosity and normal stress differences. In agreement to full-blown numerical calculations and experiments we find a shear-thickening or -thinning behavior depending on whether the particles are contractile or extensile. Moreover, our analytical approach predicts that the normal stress differences can change their sign in contrast to passive suspensions.
authors.affiliation: Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford, United Kingdom. s.heidenreich1@physics.ox.ac.uk
authors.forename: Sebastian
authors.initials: S
authors.lastname: Heidenreich
authors.forename: Siegfried
authors.initials: S
authors.lastname: Hess
authors.forename: Sabine H L
authors.initials: SH
authors.lastname: Klapp