Droplet Impact on Thin Films: Vortex Ring Dynamics

This paper investigates the fundamental fluid dynamics of droplet impact on thin liquid films, a phenomenon relevant to various industrial processes and natural occurrences. The study's focus on vortex ring formation, propagation, and instability provides valuable insights into momentum and species transport within the film. The use of experimental techniques like PIV and LIF, coupled with the construction of a regime map and an empirical model, contributes to a quantitative understanding of the complex interactions involved. The findings on the influence of film thickness on vortex ring stability and circulation decay are particularly significant.