Correlation between Pressure Minima and Cavitation Inception Numbers: Fundamentals and Hydrofoil Flows

Abstract

Cavitation inception predetermines a jump of noise radiated from marine vehicles. Usually marine propellers are the main sources of such a noise. In the situation of cavitation inception near the blade’s leading edge, its prediction remains a challenge. Though contemporary CFD tools for fully turbulent flows satisfactorily predict pressure distribution around cavitation-free blades and with cavities of length comparable with the blade size, analysis of blade cavitation inception is a difficult task for these tools. On the other hand, there are validated computational tools for 2D multizone flows capable of predicting cavitation inception. There is the possibility of considering the real 3D flow around the leading edges of blades as a 2D flow with the known pressure distribution along the blade section; the cavitation inception number is computed in this 2D cavitating flow, and correlations between this number and the pressure minimum in cavitation-free flow around the same section are determined. Such a correlation would be usable with any tool for cavitation-free flow. The issue of their applicability to arbitrary blades can be solved with the employment of asymptotic solutions for the pressure around contours with rounded leading edges.