Identification of frequency modes and spectral content for noise suppression: Cavitation flow over 3-D hydrofoil with sinusoidal leading edge

Abstract

The impetus of this study is to provide an in-depth insight into the unsteady hydrodynamic characteristics of the cavitating flow, effects of the wavy leading edge (WLE) on the noise suppression mechanism due to a cavity cloud formation, which contains condensation, detachment, collapse, spanwise flow, streamwise velocity fluctuation, and shedding phenomenon. NACA 634-021 hydrofoil was considered with WLE having a wavelength of 25% and an amplitude of 5% of the mean chord length and was compared to a straight-leading-edge (SLE) hydrofoil at cavitation numbers of [Formula: see text] and a chord-based Reynolds number of [Formula: see text]. Counter-rotation vortices were produced between the peaks of the WLE hydrofoil by destroying the horseshoe vortex and delaying the tail vortex, changing the frequency. Here, the hydrodynamic forces have also been discussed in addition to the noise. The results showed that the leading-edge vortex formation and flow separation dynamics fundamentally differed between the SLE and the WLE hydrofoil. The main difference between the WLE and SLE hydrofoil turbulent flow is the formation of counter-rotating streamwise vortices pairs. We solved the cavitating flow using the large eddy simulation (LES) approach, as well as the Kunz mass transfer model, which is performed under the framework of the OpenFOAM package.