Experimental study on the translation behavior of an in-situ bubble pair in the ultrasonic field.

The dynamics of acoustic cavitation bubbles hold significant importance in ultrasonic cleaning, biomedicine, and chemistry. Utilizing an in-situ normal pressure bubble generation and observation system that was developed, this study examined the translational behavior of micrometer-scale normal pressure bubble pairs with initial radius ratio of 1:1 and 2:1 under ultrasonic field excitation. A velocity-distance curve was proposed to quantify the secondary Bjerknes forces during various interaction stages of the bubbles.