High speed cine observations of cavitating flow in a duct

The dynamics of cavities produced in cavitating flow confined in a duct was studied. The ultimate purpose of the work is to develop models of the flow to assist in predicting cavitation erosion and noise. Observations of the cavitating flow using high speed cine photography allowed confirmation to be made of the shedding mechanism originally described by Knapp, and measurements of the cavity dimensions to be determined as a function of time. It was found that the time for a cavity to collapse was found three times greater than expected from Rayleigh's classical theory.