Defining of optimum form parameters at the initial design

A ship traveling obliquely to the direction of wave crests will experience a complicated series of oscillations in the analysis, these motions are considered as the summation of six components, three translational and three rotational. The motion composed of these six components is referred to as one in six degrees of freedom. One of the special simplified cases for investigating the motions of a ship in harmonic waves is the one that the ship travels in a direction normal to the wave crests and experiences only surge, heave and pitch motions in the plane of symmetry. The oscillatory surging motions do not appear to be of direct interest in defining the seagoing qualities of the ships. In the scope of this study, the pitching and heaving motions of a ship traveling in regular head seas are investigated. The method is divided into major parts and transferred into tables in database program so that the application of the method is facilitated. Two case studies are carried out for verifying the prepared tables. The heaving and pitching motions of a 32 type I.T.U. fishing vessels form in regular head seas are investigated by using Adria1 program, the tables prepared using a database and a ship motions program. At the conceptual design stage, a fast and comprehensive method is developed to be used in the evaluation of design alternatives. In the introduction, the ship motions are defined and an extensive literature review is given on the subject. In the second chapter, input database is obtained by estimating geometric and environmental parameters for ships. Seakeeping database is established using the data for the calculation of heave and pitch motions. In the section, the relationship between hull parameters and seakeeping characteristics is investigated. Finally in the conclusions, general assessment of the method used, application of the method and prospective studies are explained. Keywords: Fishing Vessels, Conceptual Design, Ship Motions, Data Analysis, Regression