Hydrodynamics and Scour Simulation on an Artificial Reef Applied in Offshore Wind Farm

Abstract For greater ecological benefit and more fishery resources, the industrial integration of offshore wind farms (OWFs) and marine ranches has been proposed as an important development direction. Additional artificial reef (AR) is a part of this concept; however, such structures deployed around individual wind turbines can also change flow features, thereby influencing the scour near the pile foundation. It is of great significance to combine ecological enhancement and scour protection effects. This study aimed to test a type of conical AR structure applied in OWFs. The AR was designed with holes. Different AR slope lengths and angles were used for optimization. Commercial CFD software FLUENT was adopted for solving the flow features around a monopile and AR structure in a supercritical Reynolds number condition, by using the k-ϵ RNG turbulence model. The sediment transport was simulated using Eulerian multiphase model. The scour protection and vertical flow mixing effects were selected as main indicators for the assessment of AR performance. Results showed that this AR design can not only mitigate the scour but also strengthen vertical flow mixing in the mid-up water depth. It is expected to increase the ecological benefit in OWFs. The AR of a medium size with an angle near 45° is suggested for the best performance. This research can support the future combination of OWFs and artificial reef development.