Vortex cavitation: Applications of active acoustical scanned array

Cavitation means rapid transformation of liquid to vapor phase due to a sudden and violent pressure drop. The evolutions of vaporization of the vapor phase have been investigated since the early 19th century. Recently, people have realized that it might be possible to control and utilize cavitation energy. Various approaches have been implemented to trigger cavitation intentionally at specific locations and at specific times. The energy from the collapsed bubble will blast the designated area. The challenge is to provide as much as cavitation energy will keep the pressure low. Here, we introduce acoustic vortex beams in cavitation, demonstrating how they enable the release of more energy while maintaining controlled negative pressure. These acoustic vortices bring in additional in-plane momentum, facilitating bubble evolution. This process leads to the twisting, convergence, and thus the shaping of bubble clouds. Compared to conventional ultrasound-induced cavitation, our vortex-induced cavitation releases significantly more energy into the surroundings through the collapse of gigantic bubble clusters. This makes it a promising technique for enhancing current industrial processing methods and enabling innovative bio-clinical applications.