Microbubble Self-Trapping to Surface of Target

Abstract

Microbubble self-trapping to the target surface is proposed. The Bjerknes force, which is produced by bubble nonlinear oscillation upon pumping ultrasonic wave radiation, acts as a trapping force on the target surface. A condition for the minimum separation between the neighboring bubbles is required in order to initiate self-trapping. Experiments are carried out using an ultrasonic wave contrast agent. Silicone resin, acrylic resin, and agar gel are examined as targets. Mechanisms by which already self-trapped bubbles promote further self-trapping are observed.