Simultaneous impact of twin drops on a semi-infinite liquid target

Abstract

We take the enduring topic of drop impact on a deep pool of similar liquid further by allowing twin drops to impact simultaneously. Impacts are sufficiently proximal that impact crowns and craters interact, distorting and merging craters, and creating previously undocumented supersurface fluid interactions. The unique features of twin impacts occur when crowns collide to create a central veil that bifurcates the two craters and the expulsion of jet-like features atop colliding crowns. The emergence of a plethora of splash features is dependent on the Froude number (Fr=30−200) and drop separation distance. We analyze proximal crater evolution using theory developed for singular drops and develop scaling relations to predict crown and jet height. Crater and jet energies are compared for various impact velocities and drop separation distances. We find that craters close enough to merge produce thicker, but not higher, rebound jets.