Production of secondary drops during the single water drop impact onto a plane water surface

The normal impact of single water drops onto a plane water surface was studied experimentally to reveal the amount of secondary drops produced from the rim of crown-like interfacial structure. Within the experimental ranges tested, the ratio of the total mass of secondary drops to the mass of primary drop was approximately within 0-1 and correlated well as the function of dimensionless parameter K that consisted of the impact Weber number We and the Ohnesorge number Oh (K = We Oh(-0.4)). The dependences of the number and the mean diameter of secondary drops on K and dimensionless film thickness were also investigated.