Wind turbine wake characteristics in an atmospheric boundary layer far wake physical and numerical modelling

This paper combines a wind tunnel and a numerical study about the wind turbines wakes. Results in homogeneous flows are presented before comparisons in a moderately rough atmospheric boundary layer (z₀ = 0.06m, α = 0.17, turbulence intensity at hub height = 14%). Wind turbines were modelled in a wind tunnel as porous discs made of metallic mesh at a geometric scale of 1:400. The induction factor, which represents the operating point of the modelled wind turbine, was fixed equal to 0.12 (C_T = 0.422, C _P = 0.372). In the numerical simulation, wind turbines were modelled as porous discs as well, using pre-processed source terms to model the thrust and the rotation of the blades. The input velocity conditions were chosen to respect the induction factor of 0.12. The purpose of this work is to prove the validity of both models, respecting the 'actuator disc theory'. The final aim is to work on wind turbine interactions in order to optimise the layout.