Cloud cavitation on an oscillating hydrofoil
Cloud cavitation, often formed by the breakdown of a sheet or vortex cavity, is believed to be responsible for much of the noise and erosion damage that occurs under cavitating conditions. For this paper, cloud cavitation was produced through the periodic forcing of the flow by an oscillating hydrofoil. The present work examines the acoustic signal generated by the collapse of cloud cavitation, and compares the results to those obtained by studies of single travelling bubble cavitation. In addition, preliminary studies involving the use of air injection on the suction surface of the hydrofoil explore its mitigating effects on the cavitation noise.
We wish to acknowledge our debt to Y.-C. Wang, J. Ando, F. d'Auria, T. Waniewski, R. and V. Zenit, and Z. Liu for help in conducting the experiments. Joe Fontana's machine shop assistance was greatly appreciated as well. The authors are grateful for the support of the Office of Naval Research under grant number N00014-91-J-1295.