Radiation force on a bubble located near an interface.

Abstract

The presence of a boundary produces marked changes in the oscillation amplitudes and types of bubble distortion modes excited by an external acoustic field. In the majority of cases, the radiation force can be determined based on the linearized equations of motion. Bispherical coordinates are used to obtain an analytical description of linearized bubble dynamics at distances from the interface comparable to those of the bubble size. In the limit of weak dissipation, explicit formulas have been derived that describe the dependence of the radiation force on the separation distance between the bubble and the interface, the material parameters of the contacting media, and the angle of incidence of the incoming wave. The component of the radiation force directed to the interface has been shown to exhibit qualitative changes when the direction of the incoming field passes through the angle of the total internal reflection.