The inception of tip vortex cavitation is very sensitive to water quality. In order to quantify the effect of water quality on the inception of tip vortex cavitation, we develop a motion model to describe the migration and growth of nuclei in water. An analytical solution of migration of nuclei in a vortex flow is obtained so that the capture times of various nuclei can be given out directly. A criterion is built to determine the critical nucleus in a certain nuclei spectra distribution. Tensile strength of the critical nucleus is used to quantify the effect of water quality and correct the tip vortex cavitation inception number. Finally this change of cavitation inception number is compared with experimental results to validate our model.
The inception of the tip vortex cavitation(TVC) is a very important problem in cavitation researches. The study of the mechanism of the TVC inception is not only conducive to its prediction, but also helps to suppress or suspend the occurrence of cavitation. In this paper, the research progresses on the TVC inception including theoretical, experimental and numerical studies mainly in the last two decades are reviewed. It is shown that the TVC inception is affected by complicated factors, such as the water quality, the average pressure and the fluctuating pressure. In the scaling law for the determination of the TVC inception, all these factors are considered. To precisely describe the scaling law, more investigations are needed to understand the effects of the water quality and the fluctuating pressure.
