Detached eddy simulation of large scale wind turbine wake in offshore environment

The rapid growth of the global offshore wind market underscores the need for accurate numerical simulations to support the development and design of offshore wind farms, especially in regions like the Mediterranean where measured data on marine-weather conditions for use in offshore wind farm design are rare. This paper addresses the challenge of proposing a reliable simulation framework to assess the impact of resolving sea waves on wind turbine wake simulations. A case study is defined using reanalysis data to derive possible met-ocean conditions for a 15 MW offshore wind turbine in operation at a Mediterranean site. The simulation framework employs a one-way coupling between waves and aerodynamics, an aeroelastic actuator line model to compute the wind turbine rotor dynamics and its integration into a hybrid LES-URANS turbulent flow simulation of the surrounding wind field based on the k−ω SST Improved Delayed Detached Eddy Simulation. Atmospheric turbulence is accounted for by using a stochastic wind inflow generator based on the Kaimal velocity spectrum. Wave motion is resolved using a dynamic mesh solver. Results are provided and discussed in terms of the investigation of the effects of resolving the wave motion interaction on wind shear, rotor wake, turbine loads, and performance. •Simulation framework coupling hybrid LES/RANS, dynamic mesh, ALM and FEM beam models.•Simulation resolves sea waves to assess wind shear, rotor loads, and wake behavior.•Aligned wind-wave scenarios show a stronger velocity gradient near sea level.•Lower turbine power computed for in resolving wave affected scenarios, with increased load fluctuations.•Wave effects on wind shear, critical for turbines at lower elevations, are highlighted.