An Improved Boundary Element Analysis of Cavitating Three-Dimensional Hydrofoils

Abstract

A theoretical analysis of three--dimensional cavitating flows based on a boundary element approach which includes rotational and viscous flow effects is presented. Partial sheet cavitation is studied by a closed--cavity nonlinear model which includes the prediction of the cavity detachment point. The trailing vorticity path is described by a wake--alignment technique. Viscosity effects are included via a viscous/inviscid technique based on boundary--layer assumptions. Cavitation modelling, wake alignment and viscous--flow correction are integrated into the potential--flow solution by BEM through a coupling procedure. Comparisons of present numerical results with experiments and numerical results in the literature show the capability of the proposed methodology to take into account viscosity effects on attached cavitation, and to analyze the flowfield in the tip--vortex region.