Start-up of a strongly extensional flow of a dilute polymer solution (Q1340691)

We consider an impulsively started flow of a dilute monodisperse polymer solution for which the Reynolds number is low but the Weissenberg number may be large. The polymers are modelled as linear-locked dumbbells, and the aspect ratio of the flow geometry (a `cross-slot') is taken to be sufficiently large that lubrication methods can be applied. The flow is computed using a novel mixed Lagrangian-Eulerian formulation that is particularly well suited to the asymptotic method. The numerical method is checked by comparing its results with known expressions for steady extensional flows.