A numerical study on in-plane wave propagation in mooring cables

摘要

This study presents the results of a numerical analysis of wave propagation in a mooring cable, focusing on structural waves that form and propagate in mooring cables. For mooring cables, there exists another source of nonlinearity besides the hydrodynamic effect and geometric stiffening effect, that is the seabed interaction. To study the wave propagation in mooring cables including these nonlinearities, a numerical analysis is carried out in this paper. Herein the partial differential equations describing the dynamics of the submerged mooring cable formulated in Lagrangian reference frame are used and they are further solved using space-time finite difference method. In particular, the in-plane wave propagation in a typical mooring cable partly grounded on the seabed is studied. Numerical results for the cable under fairlead excitations are presented. The characteristics of the wave propagation from the fairlead to the seabed anchor and wave reflection at the seabed touching down point are discussed.