Abstract
With the growth of marine ranching and offshore wind power, finding sustainable ways to protect the ocean environment has become vital. Offshore wind power, a key renewable energy source, helps reduce carbon emissions and promote clean energy. Meanwhile, marine ranching enhances biodiversity and supports ocean conservation by cultivating marine organisms. A new approach combines these benefits by integrating artificial reefs with fixed offshore wind turbines. This strategy aims to restore marine ecosystems while mitigating foundation scouring caused by turbine-seawater interactions. This dual-purpose solution protects marine life while improving wind turbine stability. Despite growing interest in this integrated approach, quantitative research on the hydrodynamic effects of artificial reefs around offshore wind turbine foundations remains limited. This knowledge gap hinders the optimization of reef design for effective scour prevention. Among various types, triangular artificial reefs offer unique flow dynamical properties, but their potential remains underexplored. Methods To address this knowledge gap, this study focuses on triangular artificial reefs. The study uses experiments to investigate how artificial reefs influence the flow field around offshore wind turbine foundations. Results show that reefs placed near turbine bases significantly alter the local flow environment, triggering key phenomena like the venturi effect, blocking effect, and flow guidance. These effects change the mean flow velocity and the spatiotemporal distribution of turbulence within the flow field, which in turn profoundly affect the dynamics of the surrounding environment. The venturi effect, for example, accelerates water as it flows through narrow gaps between reefs, creating areas of increased velocity. Conversely, the blocking effect slows flow velocity in certain regions, creating sheltered zones that may benefit marine life. Numerical simulations were conducted to analyze the bottom shear stress and the spatial gradient of the flow field. These simulations revealed the mechanisms through which artificial reefs alter scouring around offshore wind turbine foundations. By modifying flow patterns, the reefs effectively lower scour intensity at the base of the piles, providing a protective shield for the foundations. Results The study found that the shear stress gradient, particularly changes in shear stress across the flow field, directly affects the extent of scour. Areas with higher shear stress experience more intense scouring, while regions with lower shear stress show reduced effects. This information is crucial for designing effective scour protection systems to enhance the durability and stability of offshore wind turbine foundations. Experiments were conducted to further investigate the role of artificial reefs in preventing scour. The results showed that the proper arrangement and configuration of triangular artificial reefs significantly reduced scour around turbine foundations. The shear stress gradient was found to be a key factor affecting how the flow is redirected and how well the seabed remains stable around the turbine piles. Conclusions This study provides valuable insights into the hydrodynamic characteristics and scour protection potential of artificial reefs when combined with offshore wind turbine piles. The findings deepen our understanding of how these reefs influence flow dynamics and provide practical recommendations for optimizing the design and deployment of artificial reefs as a sustainable solution. By addressing marine ecosystem restoration and structural protection, this research serves as a foundation for future studies that aim to develop more efficient and environmentally friendly offshore wind power solutions.