Distribution of the Drop Substance in the Target Fluid at the Coalescence Intrusive Mode

High-speed video recording was used to trace the matter transfer pattern of a free-falling water drop and of the deformation of the free surface of the target fluid at the intrusive mode when the available potential surface energy (APSE) exceeds the kinetic energy of the drop. The free surface of the unified drop-target fluid system remains convex at the initial submerging stage. The inflowing drop forms a lenticular intrusion in the fluid bulk, which gradually transforms into a vortex ring. A cavity begins to form with a time delay Δt = 10 to 12 ms. The cavity surface includes traditional flat, spherical, cylindrical and conical sections moving at different velocities. The temporal variability of the intrusion and cavity geometry was traced. The drop substance is preserved as individual fibers in the wake of the submerging ring.