Rheological Aspects of Drops Deforming in Finite Reynolds Number Oscillatory Extensional Flows

The evolving morphology of droplets in a flowing emulsion determines its rheological properties. A two-way interaction between drops and the flow governs the rheological stresses arising from drop deformation. In this paper, the rheology of droplet emulsions under oscillatory extensional flow is investigated using direct numerical simulation (DNS). The deformation of a three dimensional drop is simulated. The rheological responses are related with the interface morphology using Bachelor’s stress formulation [6]. Detailed investigation of the variation of parameters such as interfacial tension, flow frequency and inertia displayed complex non-Newtonian response of the emulsion that will have broad implication in industrial applications. The results are explained and discussed with a simple model for the drop dynamics.