Drop-Liquid Impact Phenomena

Abstract

Abstract. A brief survey of several phenomena occurring when a liquid drop impacts the surface of a pool of the same liquid is presented. The review touches upon drop oscillations, liquid-liquid contact, sound emission, bubble entrapment, and vorticity generation.The initial reaction of anyone reflecting on the physical processes that take place in liquid-liquid impacts cannot but be one of surprise as the subtleties involved in such seemingly Straightforward and everyday events unfold. The squeezing of the air film just prior to contact, the rupture and joining of liquid surfaces, compressibility effects, vorticity generation, the subsequent flow with the possible entrapment of air bubbles, etc. touch on a bewildering array of complex physical and fluid mechanical issues many of which are poorly understood. Here it will only be possible to give a very concise review of some of these phenomena; for further details and more information the reader can turn to other articles in this volume and to the references.

Advances and challenges in explaining fuel spray impingement: How much of single droplet impact research is useful?

“…Based on these ratios, Tropea and Marengo [79], consider four categories of impacts onto wetted surfaces: Droplet impaction onto shallow and deep pools will not be considered here, as the condition of drop impaction onto films with dimensionless thickness, smaller than unity, is often satisfied in the engine environment [63]. Numerous works are reported in the literature addressing this subject [75,[80][81][82][83][84][85][86][87][88], including a complete review by Prosperetti [89]. Other authors, e.g.…”

“…Despite the active research on this subject [63,[79][80][81][82][83][84][85][86][87][88][89][90][91][92][93][94][95], challenges [96][97][98][99][100][101][102][103][104][105][106][107][108][109][110][111][112][113][114] remain regarding the ability to accurately predict the mass fraction of liquid deposited and the number, size and velocity distributions of secondary droplets generated at impact. Both issues are addressed in the following.…”