Cavitation erosion power as a scaling factor for cavitation erosion of hydraulic machines

The Cavitation Erosion Power based on the assumption that severe erosion is often due to the repeated collapse of the traveling vortex generated by a leading edge cavity has been formerly introduced. We have shown that cavitation erosion intensity may be scaled by a simple set of flow parameters depending on the mean upstream velocity U, the Strouhal number St corresponding to the main cavity fluctuations, the cavity length I and the pressure in the cavity closure. Further tests have been done to validate this model. In this work we present the results of synchronous pressure fluctuations measurements downstream a leading edge cavity, cavitation induced vibrations and main cavity dimensions. These results show that the pressure fluctuations may be used to qualify the aggressiveness of leading edge cavitation and that the concept of the Cavitation Erosion Power is a good basis to scale cavitation damage. Furthermore, the envelope of the vibrations signals is found to be coherent with transient pressure signals.