Assessment of cavitation regime in divergent vortex flows

Abstract

The analysis of a cavitating swirling flow in a configuration similar to the flow at the entrance of a hydraulic turbine draft tube, except the rotational component, is proposed. This flow behaviour is essential for the hydraulic turbine operation in extended range and its understanding is essential for the turbine design improvement. Advanced 2D measurements of the velocity field using PIV techniques and unsteady pressure measurements are used to determine the σ number and velocity field for various stages of cavitation development.