BUBBLE ENTRAINMENT WITH DROPS

The study reported was undertaken because recent research on nucleate boiling has implicated vapor entrainment by drops as a mechanism for vapor bubble nucleation. The mechanism has been called secondary nucleation. The purpose of this research was to determine the behavior of entrained air bubbles when a drop of liquid strikes a liquid surface. A liquid drop striking the surface of a pool of the same liquid was found usually to entrain large numbers of small air bubbles. Some of these bubbles are frequently carried rapidly deep into the pool by a vortex ring but many can be deposited in a trail or left floating on the surface. Air bubble entrainment was observed with water and several organic liquids and some differences were noted.