Model Scale Measurements of Surface Ship Radiated Flow Noise

Advances in weapon and sensor capabilities are driving an increased interest in the control of underwater signatures of naval platforms. The control of machinery and propeller noise is well understood, but there is a shortfall of knowledge of the mechanisms that govern noise due to the flow around the hull of a surface ship. The subject has been investigated in the US/NL collaborative project “Mechanisms and Prediction of Surface Ship Radiated Flow Noise”, which was carried out between 2004 and 2008 by NSWCCD (US) and TNO and MARIN (NL). The project aimed to determine and quantify the sources of flow noise generated by surface ships in terms of ship speed and hull shape. The focus was on the underwater noise generated by turbulence excited hull plating vibration and noise resulting from breaking bow waves. A combination of full scale, large scale, model scale tests and computational fluid dynamics was used. The paper discusses only the test set-up and results of the model scale underwater acoustic experiments which were made in MARIN’s towing tank.