Influence of acoustic pressure and bubble sizes on the coalescence of two contacting bubbles in an acoustic field
J Jiao, Y He, K Yasui, SE Kentish, M Ashokkumar, R Manasseh, JY Lee
Ultrasonics Sonochemistry | Elsevier | Published : 2015
In this study, the coalescence time between two contacting sub-resonance size bubbles was measured experimentally under an acoustic pressure ranging from 10kPa to 120kPa, driven at a frequency of 22.4kHz. The coalescence time obtained under sonication was much longer compared to that calculated by the film drainage theory for a free bubble surface without surfactants. It was found that under the influence of an acoustic field, the coalescence time could be probabilistic in nature, exhibiting upper and lower limits of coalescence times which are prolonged when both the maximum surface approach velocity and secondary Bjerknes force increases. The size of the two contacting bubbles is also impo..View full abstract
Awarded by Australian Research Council
We are grateful to Prof. Yos Morsi for facilitating the use of the high-speed camera. The financial support through the Australian Research Council for the DECRA (Discovery Early Career Research Award, DE120101567) is also gratefully acknowledged.