Topological rearrangements and flow simulation of dry ordered foams

Flow through a narrow bent channel may induce topological rearrangements in a twodimensional monodispersed dry liquid foam.We use the Cellular Potts Model to simulate a foam under a variable driving force in order to investigate the strain-rate response from these rearrangements.We observe a set of foams’behaviors ranging from elastic,viscoelastic to fluid regime.Bubble’s topological rearrangements are localized and their cumulative rearrangements change linearly with time,thus nonavalanches critical behavior is found.The strain-rate affects the rate of topological rearrangements,its dependence on the drag force is nonlinear,obeying a Herschel–Bulkley-like relationship below the foam’s flow point.