Manoeuvring Analysis of a Submarine by Coupled EFD and CFD Approaches

In this paper a coupled experimental and numerical activity dedicated to the analysis of the maneuvering behavior of a fully appended submarine is presented. The work presented here is part of the CNR-INSEAN activities scheduled in the framework of a joint Italian and Norwegian MoDs project, with the partnership of MARINTEK, under the egida of the European Defence Agency. The aim of the experimental work is mostly the collection of valuable data set for CFD benchmarking and the hydrodynamic characterization of the aft planes. Tests were carried out for two different stern appendage layouts (namely a cruciform and a X rudder configuration), allowing a comparison of the maneuverability capabilities between the two configurations. CFD studies were mainly devoted to the analysis of the flow field around the submarine and to collect hydrodynamic coefficients required by an in-house System Based Maneuvering solver. The latter has been used to perform two free running, self-propelled, maneuvers on the vertical plane.