Calm Water and Seakeeping Investigation for a Fast Catamaran

Abstract

In this paper calm water and in wave research activities on a high-speed displacement catamaran performed at CNRINSEAN in collaboration with the IIHR are presented. The selected geometry is the DELFT-372 catamaran, for which a large database is in construction through a series of NICOP projects. Calm water activity was carried out for the analysis of the interference phenomena; resistance, trim and sinkage tests have been performed for both the monohull and the catamaran with several separation lengths and for a wide range of Froude numbers (Fr=0.1?0.8). Experimental (inner and outer) wave cuts have been also acquired for selected separation lengths and Froude numbers. Seakeeping tests with transient, regular and irregular waves are performed. Preliminarily, comparison with the experimental results in regular wave carried out at DELFT have been done. Seakeeping transient tests allowed the identification of the Froude number of maximum response; once it has been determined, regular wave experiments were used to assess the role of the nonlinearities on the hull motions at that Fr: several steepness and wavelengths of the incident wave system were considered. The measurements collected are a valuable data base for both hydrodynamic studies of high speed catamaran and CFD validation