DEFORMATION AND POSITION OF ACOUSTICALLY LEVITATED LIQUID-DROPS

A new numerical method has been developed for studying the static defo rmation of an acoustically levitated liquid drop in air. After the Fou rier transformation is applied to the original integral form of the He lmholtz formula for the scattering of an axisymmetric acoustic wave by an incompressible liquid drop, solutions which are valid for all degr ees of axisymmetric deformation up to the point of drop break-up are o btained. Calculations are presented for drops in both gravity and grav ity-free environments, and are found to be in good agreement with expe rimental measurements by others. A physical picture of the competing p rocesses introduced by drop deformation in a sound held is also presen ted. The predictions for the Ig case can be applied to ground-based ex periments in which surface properties of acoustically levitated drops are being measured. (C) 1996 Acoustical Society of America.