Time domain approach for computing the mooring force of a mooring system subject to wind, waves and currents

The mooring force of a buoy mooring system subject to wind, waves, and currents in oceanic engineering is a difficult engineering problem. A time domain approach was developed to predict the mooring force of a buoy mooring system subject to various fories. Nonlinear fifth-order Stokes and design-wave methods were used to analyze the wave load, with empirical formulas used for the current and wind loads. Initial conditions from a quasi-static method were used to begin the time history analysis of the vessel and mooring forces without considering the impact of the dynamic effects of the chain and the buoy on the vessel motion. Then, 2-D plumped mass method was used to model the chain and buoy, with the dynamic equations solved by the Houbolt approach to correct the mooring force. The computational results compare well with experimental formulas, and the time domain approach can be used to accurately compute the mooring force on buoy mooring systems.