On the flow field characteristics around jacket foundations of offshore wind turbines under wave action

: Jacket foundations have recently emerged as a predominant support structure for offshore wind turbines in intermediate water depths. Their stability impacts structural safety and power transmission efficiency. Wave-induced flow field characteristics around jacket foundations can generate sediment erosion and local scour, leading to reductions in structural bearing capacity. However, studies on the dynamic evolution of near-field flow around jacket foundations under wave loading remain limited. This study employs numerical modeling to systematically analyze the flow velocity, vorticity structure, and turbulence characteristics in the vicinity of jacket foundations for various wave conditions. The numerical framework is rigorously validated against experimental measurements. Subsequently, OpenFOAM is employed to simulate wave-jacket interactions, while the volume-of-fluid (VOF) method is coupled with an LES turbulence closure. Results reveal that wave period, wave height, and water depth significantly influence the flow field characteristics, with distinct velocity and vorticity distributions observed between crest and trough phases. Notably, flow separation and vortex generation are more prominent under shallow-water conditions, whereas velocity gradients attenuate in deeper water. These findings offer crucial insights for the design optimization and risk mitigation of jacket foundations, ultimately enhancing the safety and stability of offshore engineering structures.