Detachment Behavior of Single-Curved/NonCurved Particles from Ultrasound-Assisted Oscillation Bubbles

Detachment behavior of single glass particle with the same mass but different shapes from an oscillation bubble driven by the ultrasound energy was investigated. The maximum acceleration of particle motion was calculated based on the oscillation of the bubble bottom point. The maximum acceleration increases with the increasing ultrasonic amplitude. Curved (cylindrical and sphere) particles attach onto the bubble mostly by the curved surface, while noncurved (cube and triangular prism) particles attach onto the bubble mostly by the plane surface. The detachment of noncurved particles requires a larger ultrasonic amplitude than that of the curved particles, whereas a larger ultrasonic amplitude means a larger driving force for the oscillation of the bubble. The detachment force of noncurved particles from the bubble is higher than that of curved particles because of the presence of larger contact areas between noncurved particles and the bubble as well as the sharp edge of noncurved particles, which provides the stable attachment.