APPLICATION OF LINEAR SUPERPOSITION TECHNIQUES TO THE ROLL RESPONSE OF A SHIP MODEL IN IRREGULAR BEAM SEAS

摘要

This report presents experimental results on the roll response of a Series-60, 0.60 block coefficient ship model in long-crested Irregular beam waves with significant heights of 1,3 to 4;3 percent of the model length. Model speed was varied from zero to that corresponding to a Prouder number of 0.158. Roll transfer functions derived from the measured roll and wave spectra as determined by linear superposition techniques are compared, to study the linearity of roll response.nMeasurements of the roll-damping in calm water, for the same speed range, are presented. The effect of speed on the magnitude and linearity of roll-damping Is also examined.nIt Is concluded that the principle of linear superposition can be used with reasonable engineering confidence In studying the roll response of fast cargo ships under way In moderate to severe seas.