Phenomena of droplet-surface interactions

The fluid flow associated with impinging droplets is rather complicated and not understood in detail. Depending on the circumstances, different characteristic features are observed. Various phenomena can appear when a droplet impacts a surface. The outcome of an impact depends on the droplet properties and of the impacted surface, which may be, for example, a dry or liquid surface. Following a dimensional analysis, the number of independent parameters can be reduced to a set of dimensionless groups that governs the process considered. An important dimensionless parameter for impact processes is the impact Weber number. However, this number alone is not sufficient to classify different types of droplet impact. Different outcomes of droplet-surface interaction will be discussed in the present paper. Our consideration is limited to the interaction of single droplets with different horizontal and inclined surfaces.