Strength Analysis Of Overall Ship FEM Model And Simulation Of Ship Collision

With the widely applications of the aluminum alloy to the shipbuilding industry, the number of aluminum-alloy vessels is gradually increasing. Aluminum vessel has been the favor of many shipowners due to its characteristics of rapidity, corrosion resistance, and environmental protection. Since the shipbuilding industry in our country is facing the contradiction of the surplus of laggard productivity and insufficiency of high-end productivity in recent years, people are putting more energy into the development of new types of ship and high-performance ship. The development of the new types of ship includes the innovations of the new hull shape, such as the trimaran and the pentamaran, as well as the applications of the new hull materials, such as composite vessels and aluminum vessels.In this thesis, two aspects of research on the strength and the collision analysis have been carried out based on my participation in the design of the46m aluminum highspeed crewboat. With the development of the finite element method (FEM) and computer technology, numerical calculation method has become a common method for people to study and solve problems.The large commercial finite element software ABAQUS is employed to compute and solve the problems of two parts of the thesis. In the first part, the finite element model of the whole ship has been established using the commericial software Hypermesh and the strength analysis of the whole ship has been performed using the ABAQUS/Standard module. Seven working conditions have been selected to be calculated and the maximum stresses of the hull structure are obtained to evaluate the structure strength with the allowable stresses under these working conditions. In addition, the cause of maximum stress occurring has been briefly discussed. In the second part, the finite element model of the bow is further refined and the collision of the bow and the rigid wall has been analyzed by utilizing the the ABAQUS/Explicit module. The collision-forces and the deformations and the energy absorptions of each component of the ship versus time are obtained. Compared to the empirical formulae and other traditional methods, the detailed characteristics of these parameters as a function of time can be obtained precisely. At the same time, numerical simulation of the ship collision under different initial collision angles and initial velocities have been performed, meanwhile the effects of parameters on the ship collision can be taken into account.