The Nucleation of Cavitation in Aqueous Media
Abstract
This dissertation on cavitation nucleation is concerned with both the cavitation nucleus and the mechanisms by which the nucleus is stabilized. The three most plausible theories of the cavitation nucleus are: the crevice model, the surfactant skin model, and the ionic skin model. The previous crevice model required that, in order for a vaporous cavity to grow from a crevice nucleus, the liquid gas interface must reach the receding contact angle. This condition is necessary but not sufficient. An additional criterion is that the radius of curvature of the interface must be greater than a critical radius, beyond which the cavity is mechanically unstable. Using these nucleation criteria, the model is rederived. Both old and new crevice models predict the cavitation threshold as a function of surface tension and temperature well. However, they diverge when predictions of the threshold as a function of dissolved gas content are considered. The old crevice model predicts a linear dependence but experiment shows the threshold increases rapidly with decreasing gas content. This behavior is predicted by the revised model. In addition to vaporous cavitation, the revised model is applied to diffusion cavitation and is shown to predict features present in the data previously explained only in terms of the varying- permeability model.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 25, 1985
- Accession Number
- ADA150745
Entities
People
- A. A. Atchley
- L. A. Crum
Organizations
- University of Mississippi