Based on the cavitation erosion test of a real injector

the micro cavitation erosion in the injector nozzle was detected by X-ray CT scanning. To obtain the specific influence of cavitation on erosion

special attention was made on the characteristics of cavitating flow and cavitation erosion in a simplified rectangle nozzle orifice based on a self circulation visualization experimental setup that can obtain cavitation area

erosion area and morphology at the same time as well as with a high-speed digital camera and the scanning electronic microscopy technology (SEM). The results show that with the increase of injection pressure

cavitation grows more intensely

and four different flow states appear in succession: single-phase flow

incomplete cavitating flow

super cavitating flow

and hydraulic flip. The cloud cavitation shedding shows a certain cyclic periodicity. The cavitation erosion region at the downstream of the nozzle orifice appears in the area of cloud cavitation shedding and collapsing

and the cavitation erosion phenomenon exists at the junction of cavitation and liquid phase. It can be reasoned from the results that the cloud cavitation shedding and collapsing as well as condensation collapsing are two main factors of cavitation erosion.