Evolution of jets during drop impact on a deep liquid pool

Abstract

The impact of a liquid drop on a liquid pool has been widely investigated. The transition regimes between coalescence and splashing of drops include jet formation with single or multiple secondary drops. One of the main features in this regime is the formation of a central liquid jet followed by breakup of the jet in the form of drops. Earlier studies have shown that the diameter of the secondary drop lies between 0.58 and 0.94 times the diameter of the impacting drop. We perform investigations based on a coupled level-set and volume-of-fluid method to elucidate the earlier observations. The investigations reveal the creation of a variety of secondary drops depending on the impact conditions. The present study also reveals that secondary drops larger than the initial drop can be obtained at higher impact velocities. We identify the importance of cavity shapes on the formation of jets and the pertaining parameters that are responsible for drop ejection.