Hydrodynamic assessment and optimization of new fast foil assisted SWAMH

This paper presents the hydrodynamic assessment and optimization of a new hybrid vessel concept, characterized by an underwater Small Waterplane Area Mono Hull (SWAMH) assisted by a tandem hydrofoil system. It has been designed by a widely known Italian shipyard specialized in the design and construction of foil assisted fast marine vehicles. The results here presented include the prediction of tandem wings performance and set-up by means of a threedimensional panel method for lifting bodies. In this way it has been possible to isolate the interference effect between the forward and aft wing system and the interference effect caused by the hull on the wings. The wave and total resistance of the underwater hull has been predicted using a linear free surface numerical panel method, developed by the authors and successfully applied also in this case in terms of correlation with experimental model tests. Finally an integrated optimization algorithm exploiting the mentioned CFD methods has been applied to obtain an optimized underwater hull form, able to minimize the wave resistance and the far field waves generated by the vessel at the design speed. The optimum hull form so obtained, is presented and its main characteristics discussed. © 2007 American Bureau of Shipping.