Numerical study of tip vortex cavitation inception using a bubble dynamics model

A bubble dynamics model coupled with a bubble motion equation were applied to study the real flow effects on the prediction of cavitation inception in the tip vortex flow. A three-dimensional steady-state tip vortex flow obtained from the Reynolds-Averaged Navier-Stokes equations was used as a prescribed flow field through which the bubble was passively convected. A `window of opportunity' through which a candidate bubble must pass in order to be drawn into the tip-vortex core and cavitate was determined for different initial bubble sizes. It was found that bubbles with larger initial size can be entrained into the tip-vortex core from a larger window size and also had a higher cavitation inception number.