INFLUENCE OF DYNAMIC INTERFACIAL PROPERTIES ON DROPLET BREAKUP IN SIMPLE SHEAR-FLOW

The breakup of droplets in an inhomogeneous flow is the key to emulsif ication. Frequently, the local flow experienced by the drops is a (qua si-) simple shear flow. The breakup of droplets in a steady, simple sh ear flow in the absence of emulsifiers has been studied extensively. I n the presence of emulsifiers, the droplet interface may acquire visco elastic properties, which are important in the prevention of coalescen ce, but their influence on droplet breakup has not been established so lidly. This article reports on a phenomenological approach, which link s the droplet breakup dynamics to the interfacial viscoelasticity, ide ntifying the latter with the elasticity modulus of a deforming planar interface. Over a viscosity ratio range of three decades, the results have been found to agree with the model, which uses only independently known quantifies derived from equilibrium interfacial tension propert ies.