Collisions of drops with an immiscible liquid jet

International audienceWe investigate the collisions of a regular stream of drops with a continuous immiscible liquid jet. By varying the jet and drop diameters, their velocities, and relative orientation, we observe a broad variety of liquid structures, some of which have a high applicability for capsule and advanced fiber production. First, these structures are described and classified into four regimes that account for potential liquid fragmentation and the resulting liquid distribution. Fragmentation mechanisms are proposed based on a physical analysis accounting for the problem geometry, the system inertia, and the system's surface energy. Corresponding dimensionless numbers are built, which are used to draw two-dimensional regime maps that can very well distinguish the experimental outcomes. Finally, the effects of viscosity, qualitatively evidenced by employing various liquid pairs, are discussed