Cavitation bubbles dynamics and cavitation erosion in water jet

•A cavitation model with sound interaction predicts dynamic process of bubbles.•Sound interaction among bubbles has an influence in water jet cavitation erosion.•Cavitation jet produce a higher impact pressure than conventional jet.•Single crater and pits-group form on damaged area of specimen. A water jet test rig is used to the cavitation test of the brass samples. The single crater and the pits-group, are found on the specimen surfaces after 15 h test. A water jet cavitation model with the sound interaction among bubbles, is developed by applying a water pressure of water jet flow fields into the Keller-Miksis equation, so as to obtain the dynamic characteristics of the bubbles. The theorical results reveal that, the volume concentration of the bubbles has an slight influence in the excursion time of bubble in water jet test; while a higher water jet velocity or a higher pressure difference between nozzle entrance and exit can lengthen the bubble expansion and compression time. The results also show that, the cavitation erosion pits can form on the specimen surface at stage II, while cannot form at stage I and stage III, which are well verified by the present theoretical model as well as the available experiment results.