Experimental study of ventilated cavitation noise characteristics

This study investigates ventilated cavitation noise through water tunnel experiments, analyzing the effects of ventilation rate, inflow velocities, cavitator diameters, and ventilation directions. Both ventilation rate (CQ) and Froude number (Fr) significantly affect the size and closure mode of ventilated cavities, respectively. The cavitation size scale predominantly governs the noise amplitude, whereas the cavity closure mode modulates the spectral characteristics of cavitation noise. Experimentally, vortex tubes of ventilated cavities generate a distinct noise peak within the 300–1000 Hz mid-frequency band, with peak frequency exhibiting an inverse relationship with the ventilation rate. Ventilation hysteresis enables noise reduction by moderating supercavity size while maintaining stable closure patterns. Finally, the ventilation direction negligibly affects radiated noise.