Viscoelastic flow instability in planar shear flow

We report direct numerical simulations of elastic turbulence in shear-driven flow of a dilute polymer solution within a three-dimensional straight channel. Most existing approaches in the literature employ the Oldroyd-B model or its advanced version, the finite extensible nonlinear elastic model introduced by Peterlin (FENE-P model), for simulation of polymer hydrodynamics, with their limitations of being continuum models. To overcome such restriction, we explicitly model the dilute polymer solution utilizing a classical bead-spring representation for each polymer chain and, therefore, also accounting for spatial variations in polymer concentration. We show that the viscoelastic instability forms in elastic waves and eventually chaotic flow, which persists above the transition with increasing Weissenberg number further into viscoelastic turbulence.