Dynamic Analysis Of Mooring Cable

The exploitation and utilization of marine resources need many kinds of sophisticated equipments, and the floating crane is one of the essential ocean working ships in the constructions of the offshore facilities. The dynamic analysis of the mooring system is one of the most important contents of the nonlinear dynamics in the motion of floating crane. In this paper, the static and dynamic analysis of the mooring cable is done.Two kinds of methods are used for the static analysis of the mooring system in this paper. First, traditional centenary theory is used in the static analysis of the mooring cable. Second, the finite analysis method is used. The geometrical nonlinear rod element model for analysis of mooring cable is presented, and large rotational displacement but small strain of the element, flow resistance, wave force, and the interaction between the sea bed and the mooring cable are taken into account in the model. The basic chain form and tension are obtained in the paper, which are the foundation of the dynamic analysis of the mooring cable.In the dynamic analysis of the mooring system, two kinds of methods are also used. .First, mode superposition method is used based on the hypothesis that the small vibration of the mooring cable near the balance position is linear, and the natural frequencies, vibration models, and the dynamic response under sinusoidal loading excitation are obtained. Second, considering the nonlinear feature of the load, the dynamic model of the mooring cable is established by using virtual energy principle. The motion equation is solved by Wilson method to obtain the dynamic response of the mooring cable.To verify those methods of the static and dynamic analysis of the mooring cable in this paper, Procedure is developed to carry on simulation with matlab. A simulator is designed to simulate the nonlinear force applied to the ship. by the mooring cable.