Berthing Vessels Against Wind Turbines in a Real Seastate

The author proposes a method to calculate weather criteria for vessel boarding against fixed wind turbines. For such a complex mechanical phenomenon, the calculation investigates a state control model: over the time, the friction may be either kinetic or static. International guidelines prescribe that “95% waves pass with no slip above 300mm (or one ladder rung)”. To meet such acceptability criteria, it becomes necessary to investigate boarding under a real state, which is an irregular wave. Such “real-world” wave also strengthens the practical implications of the presented calculations. The calculation models the “bump and jump” against the monopile of a fixed wind turbine. Results with 1.5m significant wave height show a stable boarding condition. Other results show fender heave vs time (respectively power spectral density vs wave frequency) for 2.5m significant wave height and 7.5s wave peak period, respectively from simulation and model tank test for a surface effect ship of the same length. Simulation and model test results show the same behavior qualitatively, although both boats have different hulls. Therefore, such comparison strengths the findings. The findings meet the results from other publications. The outcome then is to propose boarding optimisation strategies, compared to present professional practices. The purpose is to achieve less gas emissions, by minimising fuel consumption. Indeed, professional boarding practices leave to be desired: boat captains apply full push rather than fine-tuning, for safety reason. Eventually a further axis of development is to investigate vessel boarding against not, but floating wind turbines.