Droplet Breakup Under a Stagnation Point Flow: Theory and Experiments

In this talk, we focus on the coupled evolution of a partially wetting drop and external wind, when the droplet is initially held against a fast stagnation point flow. We have recently developed a 2D lubrication model to theoretically predict the droplet breakup in this configuration. Following up on this theoretical study, we will present our new experimental observations of a water droplet on the solid surface when a linear jet of air is applied normal to the substrate. In addition to characterizing the critical wind speed needed for the droplet breakup, we find that introducing an offset between the initial center of the drop and applied wind can alter the droplet behavior completely. We summarize different droplet behaviors on a phase diagram and use the lubrication model to predict boundaries between different regimes.