Enhancement Effects of Underwater Acoustic Streaming by a Cylinder with a Cavity

The effect of the cylinder with a cavity on the underwater acoustic streaming generated by an ultrasonic transducer with a resonance frequency of 28.2 kHz was investigated in this study. Duralumin and acrylic materials were used to study the effect of streaming acceleration and observe the streaming distribution, respectively. Simulations and experiments were conducted at both small and large amplitudes of the vibrating surface to obtain the distributions of sound pressure and acoustic streaming. The results showed that this structure could increase the streaming velocity noticeably when the amplitude was small; however, the effect did not become more significant at large amplitudes due to the large amount of cavitation bubbles generated.