A law of reflection for skirting droplets: the scattering angle of skirting droplets that rebound from a flat wall

Without a driving force, droplets that impact a bath with a horizontal component of momentum can glide or skirt along the surface of a bath of the same fluid, traveling many droplet diameters before coalescing with the bath. These droplets will rebound from the meniscus formed on objects that protrude through the bath surface. We show here the behavior of droplets that rebound or reflect from the meniscus formed on a flat vertical wall. A linear but asymmetric law of reflection is found and compared with a numerical model that assumes an exponential meniscus profile.