HIGH SPEED PHOTOGRAPHIC STUDIES OF ULTRASONICALLY-INDUCED CAVITATION,
Abstract
On the basis of photographic studies, it is indicated that the normal collapse mode for a bubble in an ultrasonically-induced cavitation field is asymmetrical. In most cases, the bubble involutes into a torus, the direction of the involution being dependent on perturbations of the bubble surface due to pressure gradients, etc. A vortex ring is formed producing a central micro-jet, the impact of which upon a solid surface is believed to be the predominant damaging mechanism. Three collapse models are hypothesized to explain the existence of the various types and sizes of cavitation bubbles which were observed, and to also suggest the mode of a possible damaging collapse. An attempt is made to correlate the known pit damage on an individual specimen to the approximate number of observed bubbles of the type that are believed to be indicative of such a jet impingement on the specimen surface, and it is found that the order of magnitude is correct. Visible evidence of the effect of the shock waves that apparently accompany rebounding bubbles is presented. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1967
- Accession Number
- AD0824309
Entities
People
- F. G. Hammitt
- H. G. Olson
Organizations
- University of Michigan