Theoretical modelling of unsteady cavitation and induced noise

A theoretical and computational methodology to develop an integrated hydrodynamics/hydroacoustics approach for marine propeller cavitation studies is presented. The hydrodynamics model is based on a potential flow formulation that is valid to study inviscid flows around lifting bodies in arbitrary motion. A sheet cavitation model is applied to estimate the transient cavity pattern on the surface of propeller blades. Propeller-induced noise emission is studied through a general hydroacoustics formulation based on the Ffowcs Williams-Hawkings equation that allows to describe the acoustic pressure field generated by lifting bodies in arbitrary motion through a fluid. The proposed methodologies are outlined and theoretical as well as computational issues related to transient cavitation modelling are discussed in detail. Preliminary results of an ongoing activity aiming to assess the capability of the proposed approach to analyse cavitating propellers in non uniform flow conditions are presented.