Impact of drops on the surface of immiscible liquids

Impact of drops on the surface of an immiscible liquid is studied. We show that in addition to the commonly-observed lens structure at the air-liquid interface, drops released from critical heights above the target liquid can sustain the impact and at the end maintain a spherical ball-shape configuration above the surface despite undergoing large deformation. The existence of this metastable state of the drop above the free surface and its transition into the more stable submerged lens configuration at the air-liquid interface is investigated. The initial impact which induces the degree of submergence is critically related to the two distinct life paths of drops impinging upon a liquid surface. (C) 2010 Elsevier Inc. All rights reserved.