Underwater radiated noise prediction for a submarine propeller in different flow conditions

International Maritime Organisation (IMO) and other bodies have been trying to set-up guidelines and regulations to reduce/limit noise levels at sea which influence marine life in particular marine mammals and certain fish types. Ships with low noise characteristics will be a must in the near future for almost all ship types. However for special ships, such as naval surface vessels, fishing vessels, submarines, etc. this has already been an issue because of their operational requirements. The propeller is one of the main sources of underwater noise generated by ships. Therefore, it is important to predict and control the underwater noise characteristics of propellers. In this respect, the main objective of this study is to calculate propeller radiated noise numerically. Propeller noise has been investigated numerically for the INSEAN E1619 submarine propeller in open water, behind a generic DARPA suboff submarine and within imposed wake cases at non-cavitating conditions due to their deeply submerged operations. Flow around the propeller is solved with a commercial CFD software using Unsteady Reynolds Averaged Navier-Stokes (URANS), while hydro-acoustic analysis is performed using a model based on Ffowcs-Williams and Hawkings equation. This paper reports the results of the study. The paper also includes the details of the bodies and discusses further improvement of the methodology applied.