Sasaki T.,Niigata University |
Yoshida K.,Niigata University |
Nakagawa M.,Industrial Research Institute of Niigata Prefecture Japan |
Yoshida S.,Southeastern Louisiana University
Conference Proceedings of the Society for Experimental Mechanics Series | Year: 2016
The ultrasonic horns with cylindrical concave surfaces (concaved horn) have been designed and the effect of the concave on cavitation bubbles generation in water has been investigated. High speed camera observation was made on the vibrating horn tip in water and the generation behavior and the impact force of the cavitation bubbles were investigated. In the measurement of impact force, load vibration occurred as the cavitation bubbles collapsed, and peak frequencies were observed at the vibratory frequency of the horn and its harmonic frequency. The impact force was evaluated based on the above peak frequency. The result showed that the concaved horn provide the higher impact force compared to the horn without the concave. Frequency analysis of the load vibration showed that the concaved horn enhanced the generation of cavitation bubbles in the number. The distribution of cavitation bubbles on the horn-tip was evaluated using high-speed image. It was confirmed that the cavitation bubbles flow was effectively converged to the center of concave. © The Society for Experimental Mechanics, Inc. 2016.