Experimental study on the influence of hull spacing on hard-chine catamaran motions

An experimental program was performed with hard-chine catamaran models in r egular waves. The distance between the demi-hulls of the models was changed to assess its effects on the wave-induced motions. The results allowed the study of some aspects related to catamaran motions, like the interference between the hulls and resonance frequencies. The experimental results are c ompared with calculations performed with a recently developed code based on a two-dimensional potential flow theory in which viscous forces are includ ed through a cross-flow drag approach. The effect of the hull distance in t he heave and pitch motion responses and the importance of the viscous force s in such hull configurations are shown.