Flow Instabilities in Complex Fluids
Flows of complex fluids (such as polymers, colloids, emulsions, pastes etc.) are abundant in everyday life. One can think of pouring syrup from a bottle or squeezing toothpaste from a tube, but also of fibre-spinning and extrusion - processes used to produce plastic bags, optical fibres, wire coatings, guitar strings etc. Complex fluids, and polymer solutions in particular, often exhibit unexpected behaviour - they do not flow like water. Recently, it was discovered that flows of visco-elastic fluids (e.g. polymers) in simple geometries become unstable and even chaotic at very low Reynolds numbers. The origin of such 'purely elastic turbulence' is presently not understood, and this collection provides data generated as part of our research into the mechanism of such phenomena.
Items in this Collection
Code and accessories for 'Subcritical instabilities in plane Poiseuille flow of an Oldroyd-B fluid' Recently, detailed experiments on visco-elastic channel flow have provided convincing evidence for a nonlinear instability scenario which we had argued for based on calculations for visco-elastic Couette flow. Motivated ...
The lid-driven cavity flow is a well-known benchmark problem for the validation of new numerical methods and techniques. In experimental and numerical studies with viscoelastic fluids in such lid-driven flows, purely-elastic ...