Experimental Study on Bubble Motion Behavior in Ultrasonic Traveling Wave Fields

The bubble dynamics in ultrasonic fields have extensive application prospects in industrial and medical fields such as industrial cleaning, marine technologies, underwater explosions, targeted drug delivery, and non-intrusive measurement of blood pressure owing to the merit of non-pollution, non-invasiveness, and fine control of bubbles. Consequently, the comprehensive understanding of bubble dynamics in ultrasound fields is of great significance. The effect of the bubble deformation, the bubble equivalent diameter, and the bubble ascending trajectory in an ultrasonic travelling wave field are investigated. The impacts of the needle specification, the advance speed of the injection pump, and the ultrasonic transducer height on the bubble dynamics in an ultrasonic travelling wave field are analyzed. The present investigations indicate that a small bubble can levitate in liquid, and the ultrasonic travelling wave can delay the bubble generation, leading to the bubble dynamics becoming complex. Namely, the equivalent diameter of bubbles and their deformation increase under the impacts of the ultrasound.