Numerical prediction of the installation dynamics of offshore wind turbine anti-scour protection frames

Seabed scour seriously endangers the stability of fixed offshore wind turbine foundations, while conventional protection methods suffer from environmental and constructability flaws, and the deepwater deployment dynamics of large-scale permeable frame-type anti-scour structures remain unstudied. To fill this gap, this study deduces the theoretical motion equations for a six-sided twelve-sided permeable protective frame, and conducts fully coupled time-domain dynamic simulations via OrcaFlex under varied conditions. Key findings show that water depth determines horizontal drift and seabed contact time with a critical depth governing vertical velocity; current velocity only affects horizontal drift; current attenuation and direction variation induce complex rotation and torsional loads; water entry slamming force is the core load, mitigable by bottom buoyant materials with a trade-off between impact reduction and deployment efficiency. This study conducted in-depth research on the theoretical and numerical models of the deployment dynamics of such frameworks, clarified the dynamic coupling mechanism between the marine environment and the structure, and provided crucial engineering guidance for the parameter optimization and precise installation of the anti-sedimentation protection system for offshore wind turbines.