Interceptor device for a high-speed displacing craft (comparison between CFD simulation and experimental data)

The Italian Navy has performed a feasibility study about a new OPV (Offshore Patrol Vessel), characterized by very high maximum speeds and a large differences between cruise and full speed. In this study, an attempt has been developed to adequately identify hull forms and to determine the maximum effectiveness of interceptor device to be applied on the displacing hull. Simulations have been carried out by using the RANSE code CD-Adapco STAR CCM+ v. 9.06. To take into account the low reliability of numerical simulations to predict the interceptor’s effectiveness, the towing tank experiences, carried out by INSEAN-CNR Rome on the reference hull form, have been compared with the numerical simulations. Finally, different configurations of hulls have been analyzed to minimize resistance. In addition, for the same aim, different mesh sizes and turbulence models have been tested. In brief, this work is divided into the following parts:  towing tank test experiences;  choice of the more reliable numerical procedure (by validation with towing tank test);  optimization of the hull forms in relation to drag resistance evaluated for the two operational speeds;  identification of interceptor suitable size to be applied to the final hull form. Tests and numerical simulations have been performed for a length model of 8.3 m (14.931 scale), i.e., Reynolds Number (Re) > 2.1 × 107.