Wave-induced motions and loads on fast monohulls: Correlation of theoretical predictions with model and full scale experiments

Extensive model and full scale tests have been carried out with a fast, transom stern, round bilge monohull with L/B = 6.2. A model consisting of ten segments was manufactured and the vertical loads on the segments were measured in head waves with the model both free and restrained to record the total loads and the wave excitation, respectively. Tests were made also in calm water to determine the restoring forces. Full scale seakeeping trials were carried out with the same vessel both in a high and in a low sea state at five headings and several speeds. Model tests have also been run with a segmented, very slender, hard chine monohull model. Theoretical motion and load predictions by the linear strip theory show a quite good correlation with measured motions and the first harmonic component of the sectional forces, but there are very significant higher order components present in the segment forces.