Experiments on Ship Motions in Shallow Water

The results of an experimental investigation into shallow water ship motions are presented. The experiments were conducted in two parts. In the first part, the change in form of sinusoidally generated waves as they travel in shallow water were measured. The results are presented as changes in the Fourier harmonics with distance from the wave maker. Comparisons with theoretical predictions from the Korteweg-de Vries equation are made and show good correlation. &&In the second part of the experiments, measurements were made of the surge, heave and pitch motions of a tanker model in response to shallow water waves. Because the exciting waves are not sinusoidal, the waves and motion responses were Fourier analyzed. The first harmonic amplitudes were then considered to be the equivalent linear responses. The experimental results are compared with theoretical predictions made by a slender body theory of shallow water ship motions. The surge theoretical results are in reasonably good agreement with the experiments. The heave and pitch agreement is poor.http://deepblue.lib.umich.edu/bitstream/2027.42/91730/1/Publication_No_149.pd