Experimental assessment of marine propeller noise under ventilation conditions in a towing tank

Shipping has greatly increased underwater radiated noise in recent decades, impacting marine species reliant on sound. The International Maritime Organization issued guidelines in 2014, recently revised, to reduce shipping noise, emphasizing propellers as key contributors. Therefore, testing and predicting noise generated by propellers is paramount. This study acoustically characterizes the atmospheric towing tank of the Technical University of Madrid, assessing noise propagation and background sources. Results indicate that despite reverberation, reliable measurements are possible. Furthermore, noise measurements of a five-blade propeller were conducted. While design rotation rates yield weak signals, conditions like zero thrust or ventilation allow accurate acoustic assessments, suggesting towing tanks can be effective for certain operational scenarios.