A NEW PROPOSAL FOR A PASSENGERS FAST FERRY OPERATING IN THE ITALIAN ARCHIPELAGO: STRUCTURAL ANALYSIS FOR WEIGHT OPTIMIZATION BY FINITE ELEMENT METHOD

A research program is developing at the University of Naples “Federico II” whose main purpose is to individuate advanced methods for the design of high-speed vessels in aluminum alloy. The evolution of the structural design in the field of the high-speed transport has led to the application of new technologies of construction. Particularly the use of aluminium seems to be particularly suitable in the realization of fast ferry designed for small and medium coastal shipping. The structural design process for such ships must satisfy some requirements, which are the strength analysis to the local and global loads and the structural optimisation of weight. First of all a general layout configuration has been drawn starting from design data and requirements for the connections between Tyrrhenian towns and near islands, of Campania, Pontino, Tuscan and Sicilian archipelagos. The internal subdivision has been obtained basing on the HSC2000 code. Successively basing on a study that has led to a first step hull form (taking into account hydrostatic and hydrodynamic requirements), the problem of the structural analysis for such ships has been studied. It has been started from the consideration that, for an optimisation of the structural design process, a finite element method in the quasi-static form must be applied to the entire structure, in order to evaluate the “real” stresses and strains all over the hull and to identify the most critical structural elements. Finally the results obtained have been particularly discussed.