Experimental study of the transmission of vibrations and noise of an hydrofoil excited by cavitation in a hydrodynamic tunnel

Ship propellers are responsible for radiated noise in the near and far environment. One of the main sources of noise from propellers is due to the cavitation phenomenon that occurs on each blade. This phenomenon produces strong pressure fluctuations, which in turn generate noise that propagates in the ocean but also inside the boat. The strong wall pressure fluctuations excite the hull structure, which then transmits the noise inside the ship. The transmission is problematic for passenger ships and cruise liners, for whom silence is synonymous with quality. Efforts are being made to improve sound absorption and insulation, but the phenomenon of noise transmission from propellers to the hull via strong pressure fluctuations is still poorly understood. The aim of the paper is to simplify the problem studying a hydrofoil excited by a controlled flow and subjected to different states of cavitation. Vibration and acoustic measurements will be carried out to study the transmission of noise and vibration through the tunnel wall in order to be correlated to the different states of cavitation.