Cavitating wake dynamics and hydroacoustics performance of marine propeller with a nozzle

Physics of Fluids, Journal Year: 2025, Volume and Issue: 37(1)

Published: Jan. 1, 2025

Using high-fidelity computational fluid dynamics modeling, the current work studies cavitating turbulent flow of a ducted marine propeller and explores physical mechanisms underpinning underwater radiated noise. We employ standard dynamic large-eddy simulation for wake homogeneous Schnerr–Sauer model cavitation process, while Ffowcs Williams–Hawkings acoustic analogy is used hydroacoustic modeling. The modeling framework validated against available experimental data, capturing distinctive double-helical tip vortex its qualitative patterns along trajectory. In comparison to noncavitating scenario, pressure fluctuation on surface more ordered but energetic under conditions due periodic nature sheet cavity. This reflected in thrust spectrum form stronger low-frequency tonal peaks medium-frequency broadband components, high-frequency components are relatively weaker. show that enhances monopole noise source displacement by cavity with dipole quadrupole sources associated turbulence effects. Tonal frequencies corresponding harmonics blade passing frequency also increased. Cavitating structures increase energy at all orientations, particularly downstream, an sound levels up 20 dB. Finally, addition duct nozzle inhibits originating from accompanying energy, although cavitating/vortical now observed new locations around system. As result, overall power reduced configuration.

Language: Английский

Review of noise and vibration reduction technologies in marine machinery: Operational insights and engineering experience

Applied Ocean Research, Journal Year: 2024, Volume and Issue: 152, P. 104195 - 104195

Published: Aug. 30, 2024

Language: Английский