Experimental Study of Ship Propeller Noise Conducted in a Test Tank

As one of the dominant noise components on ships, studies on propeller noise still need to be carried out. Both numerical and experimental techniques are continuing to develop, to obtain noise that is caused by cavitation of the propeller. Restrictive noise at sea, especially that caused by ships, has become a widely discussed issue because it will affect marine life. Based on this background, a study on propeller cavitation noise was conducted by conducting experiments in the towing tank of the Indonesia National Research and Innovation Agency (BRIN). A B3-35 propeller model and an electric motor connected to a vertical shaft were used for this experiment. Variations in propeller rotation speed were made to generate cavitation around the propeller. The generated propeller cavitation noise signal was analyzed in the frequency domain by studying the generated spectrum. An underwater camera was used to observe the cavitation phenomena underwater. From the results of this experiment, it is found that the higher the propeller rotation speed, the greater the cavitation that appears. The resulting spectrum also shows that if the noise is recorded at a considerable distance, more frequency components will be obtained.