DELAY OF CAVITY FORMATION IN THE INTRUSIVE MODEOF A FREELY FALLING DROP COALESCENCE WITH A TARGET LIQUID
The dynamics of a cavity formed in the intrusive mode of coalescence of a freely falling drop flowing smoothly into the liquid have been for the first time traced by the methods of photo and video registration. The cavity begins to form when the downstream part of the drop is submerging, of the fluid coalescence line contracts to the center of the flow, and simultaneously with the annihilation of the drop surface, the surface of the target liquid is restored. In this case, the orientation of thin trickles – ligaments, formed in the vicinity of the contact line, changes. In the initial phase, when the upstream part of the drop coalesce they are directed outward and distribute the transmitted momentum and energy of the drop over the entire surface of the intrusion. The retraction of the coalescence line leaves the transmitted energy and momentum of the drop in the contact patch. If the kinetic energy of the falling drop noticeably exceeds the potential surface energy, the cavity begins to form at the initial contact of fluids and deepens during the entire coalescence process, capturing the drop matter.