Characterizing cavitating flow over a hydrofoil using X-ray densitometry

Hydrodynamic cavitation is a significant source of erosion on the surface of propulsors and rudders. Understanding the effect of cavity properties on cavitation intensity is key to the prediction and mitigation of erosive cavitation. Quantification of surface flow fields during cavitation is an important step in understanding the relationship between the erosivity of a cavity and its topology. In this study, we use measurements of hydrodynamic loads, in combination with high-speed optical and X-ray imaging, to characterize cavity topology. Time-synchronized surface pressure measurements are correlated with x-ray measurements to identify pressure variations caused by flow mechanisms near the surface. The findings are compared with pressure and erosion measurements from full-scale experiments performed at the Large Cavitation Channel in Memphis, Tennessee.