The underwater propeller generates harmful acoustic impacts to marine environments. The propeller tonal noise was numerically predicted by the unsteady volume variation of sheet cavitation on the blades. This procedure was validated with model propeller tests in the water tunnel facility. Two experimental methods are developed for propeller broadband noise prediction. The first method is model scale estimation through development of semi empirical formula based on tip vortex formation noise theory. The final form of this formula was modified by subsequent model tests for nine kinds of propellers with considering the transfer function of cavitation tunnel. The second experimental approach is a full scale prediction based on transmission coefficient in the stern tube area. The relationship between fluid borne sound and structure borne sound was obtained through acceleration measurements in the steering gear room, while impulsive sound was generated by the gunpowder near the propeller during the final stage of ship construction in dry dock. Finally, the model scale and full scale experimental methods were verified by underwater radiated sound measure at sea trial and showed good agreement with measured ship’s noise data.

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