Drop Decay into Individual Fibers at the Boundary of the Contact Area with a Target Fluid

Abstract

The process of disintegration of a drop (water, a saturated solution of ferrous sulfate, or alizarin ink) freely falling into water into fibers is first observed in the vicinity of the confluence line of liquids. Photo and video recording of the evolution of the flow pattern is carried out. At the bottom of the cavity, annular capillary waves covering the confluence area are visualized as well. Thin radial jets (ligaments) transporting droplet matter descending from the pointed crests of the perturbed boundary of the fluid confluence region are traced. In the mode of splash formation, the ligaments continue in the crown, penetrate the veil, and partially penetrate the spikes at the tops of the pointed teeth on its edge. Wakes of the jets colored by the drop substance form linear and reticulated structures deformed by flows and spreading out under the action of diffusion. Sprays, the sequences of gradually growing small droplets, fly out from the tips of the spikes, the size and angular position of which change with time. Additional acceleration of the fluid in the jets is associated with conversion of the available potential energy upon elimination of the free surfaces of the coalesced fluids.