Influence of centrebow on motions and loads of high-speed catamarans

Knowledge of the magnitude of expected sea loads, particularly slam loads, is a critical component of optimising the structure of large high-speed vessels. Of vital importance is an inderstanding of the vessel motions since they will directly influence the loads and also the comfort of the passengers and crew.

A segmented model of a wave-piercing catamaran has been designed and constructed to obtain experimental values of global motions and loads. Results are presented for the motions, global wave loads and slam loads, with a particular focus on the influence of the centrebow configuration. The motions were found to be distinctly non-linear with respect to wave height; this was due to the immersion of the centrebow in larger waves tending to reduce the heave and pitch motions. The wave loads were found to be dominated by the slam load on the centrebow, varying in magnitude and location with respect to wave conditions.