Dynamics of mooring systems in ocean engineering

Summary

The computation of restoring forces on floating platforms caused by mooring systems in ocean engineering is usually performed by means of quasi-static procedures. Thereby, nonlinear phenomena produced by the motion of the mooring line or the interaction between fluid and line are not considered. For lines in deep water, these effects may cause a tremendous increase in the tension force, which cannot be predicted by simplified models. Therefore, it is mandatory to determine the dynamics by means of a more precise mathematical model. In this paper, a model is presented for the analysis of the dynamic behavior of mooring systems taking into account the hydrodynamic forces exerted by the surrounding fluid. The mathematical description of the real mooring line is performed using a multibody system approach. Furthermore, a comparison of results of a quasi-static and a dynamic analysis is presented in order to stress the importance of a dynamic analysis of mooring lines.