title: Nonlinear dynamics and rheology of active fluids: simulations in two dimensions.
abstract: We report simulations of a continuum model for (apolar, flow aligning) active fluids in two dimensions. Both free and anchored boundary conditions are considered, at parallel confining walls that are either static or moving at fixed relative velocity. We focus on extensile materials and find that steady shear bands, previously shown to arise ubiquitously in one dimension for the active nematic phase at small (or indeed zero) shear rate, are generally replaced in two dimensions by more complex flow patterns that can be stationary, oscillatory, or apparently chaotic. The consequences of these flow patterns for time-averaged steady-state rheology are examined.
authors: Department of Physics, Durham University, Science Laboratories, South Road, Durham DH1 3LE, UK.
authors: S M
authors: SM
authors: Fielding
authors: D
authors: D
authors: Marenduzzo
authors: M E
authors: ME
authors: Cates