The Bjerknes forces and acoustic radiation energy

Multibubbles in a cavitation reactor are subjected to both external and mutual acoustic radiation forces. The radiation forces by a plane traveling wave, a standing wave, and radiating waves between bubbles are described. These forces influence the spatial distribution, the kinetics of bubble clustering, and bubble coalescence in the cavitation reactor, which in turn directly impacts the reactor performance. Recent developments showed that measurement of acoustic radiation energy from a multibubble cavitation field could be adapted for quantitative analysis of cavitation number density and size distribution. Further development of this approach has the potential to transform how sonochemical reactors will be designed and how cavitation processes can be scaled and optimized in the future.