Partial Rebound of a Liquid Drop on a Hydrophobic Surfaced Item

My research project explores experimentally the fundamentals of hydrodynamics of pure liquids, solvents and colloidal suspensions commonly used in painting and coating processes by drop impact deposition onto solid and porous surfaces. The image displays one of six possible outcomes of drop impact on a solid surface called “partial rebound”. Here, a pure water drop was captured few milliseconds after impact onto a 50% pre-stretched Teflon surface, and due to the impact dynamics, a partial rebound scenario originated; in which the liquid drop stays partly in contact with the Teflon surface and launches one or more droplets at its top due to the capillary instability. In particular, the image captures the exact time moment (not seen by the naked eye) when this secondary droplet is about to detach from the main drop which are interconnected by a tiny liquid filament. Additionally, the image was acquired by a high-speed camera with an acquisition frame rate of 2000 fps and back LED lighting. Finally, the goal of my research project is to develop and facilitate innovative processes of painting and coating large surface areas with less material, aiming at optimizing these processes and reducing final costs of production.