抄録
It is known that cavitation erosion cause to break the parts of fluid machinery or damage the tissue of the body during medical ultrasound, for example, ESWL : Extracorporeal Shock Wave Lithotripsy. But if cavitation behavior can be analyzed and controlled actively, we are able to utilize cavitation as a transducer, which can concentrate energy in a very narrow area. And this cavitation control has the possibilities to be applied in engineering and medical field. In order to analyze cavitation behavior in ultrasound field, we conduct experiments and numerically simulate the dynamics of bubble cloud in detail, and we obtain the following conclusions. We build the method to concentrate cavitation cloud only in a small region with high frequency ultrasound and oscillate and crush the cloud with low frequency one near the natural frequency of it. And it is possible to break an object in a narrow area by this method.
