Influence of dynamic interfacial properties on droplet breakup in plane hyperbolic flow

Abstract

Abstract Droplet breakup in laminar flows is important in emulsification processes and polymer blending. The influence of surfactants on droplet deformation and breakup in a plane hyperbolic flow was studied experimentally in an opposed‐stream device. As in the case of simple shear flow, the inhomogeneity of the surfactant distribution along the droplet interface has a pronounced effect. Our results are qualitatively consistent with other numerical studies for droplet breakup in an axisymmetric elongational flow. Also a striking similarity is noted with other experimental observations for the deformation and breakup of polymeric drops in a quasi‐steady‐plane hyperbolic flow. The critical capillary number for droplet breakup in the experiments correlates with the interfacial viscoelasticity, and a reformulation of the numerical framework in terms of interfacial elasticity parameters is suggested for future numerical work including other linear flows.