Dynamics of a Rigid Ship

Abstract

This book is primarily meant as textbook of the course Ship Dynamics provided for the students of Naval Architecture of Aalto University. The approach to ship dynamics presented in the book makes it possible to deal with the seemingly different problems such as ship maneouvring, sea-keeping and dynamic stability using the same unified mathematical model. Motion dynamics of a ship regarded as a rigid body in a general motion with six-degree-of-freedom is considered. The relation of non-linearities of the applied sub-models to the physical phenomena associated with the ship behaviour is discussed. Surface wave theory is presented. Non-linearities associated with surface waves are discussed. Realization of the unified mathematical model in a form of simulation tool, called LaiDyn, is discussed and examples of its applications are shown. Mathematical model for assessing internal hull girder loads is presented briefly. An un-symmetry of internal loads, visible as different maximum values of sagging and hogging, is presented and the origins of it are discussed.