الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Linear three-dimensional frequency-domain singularity distribution methods have become a reliable tool for the prediction of ship motions in regular/irregular seaways. Literature survey was carried out to provide state of the art review of the methods that are currently in use, their applications and limitations. In this thesis, an existing numerical model is extended to incorporate the non-potential roll damping into the original linear formulation –in an equivalent linearized form- and is estimated by the semi-empirical method due to Ikeda. In addition, the numerical model was extended to predict heave, pitch and roll motions in long crested irregular waves for a range of wave headings using user input spectrum based on wave amplitude or using idealized spectrum such as ITTC one parameter, ITTC two parameter, JONSWAP, DNV spectrum and Pierson Moskowitz spectrum based on the available data about the wave height at which the calculations were carried out. The numerical code not only calculates the response spectrum for the above mentioned motions but also calculates the average amplitude of motion, significant amplitude, one-tenth amplitude, one-hundredth amplitude, the most probable motion and the extreme motion. The accuracy of the developed numerical model has been validated by comparing the result with results available in the literature for the S-175 container ship advancing at forward speed equivalent to Fn. = 0.275 for a range of wave headings. Obtained results have shown satisfactory agreement with experimental data. In particular, the influence of accounting for the non-potential roll damping and the role it plays in predicting more realistic roll motions in regular beam seas and irregular oblique seas is clearly visualized. Also a parametric study has been carried out to study the effect of ship speed, wave amplitude, heading angle and encounter frequency on the different components of roll damping.