The two-dimensional flow of a foam through a constriction: Insights from the bubble model.

The flow of a two-dimensional foam through a constriction is investigated numerically with the bubble model, and results are compared with existing experimental and numerical studies. We predict the dynamical behavior of the foam by measuring its flowrate as a function of the imposed pressure drop. We show that two flow regimes can be observed, with an affine relationship between flowrate and pressure drop. The model also shows that the flowrate increases with the width of the distribution of bubble sizes. The simulations exhibit a power law dependency of the flowrate in the width of the constriction. The local properties of the flow are also investigated by measuring the velocity field, the frequency and direction of plastic events, and main orientations of strain. We show that the main qualitative features of the plastic and strain tensors fit with existing experiments. Finally, we test a theoretical model that predicts a relationship among plasticity, deformation, and strain. [ABSTRACT FROM AUTHOR]