Assessment of CFD Techniques for Wind Turbine Aeroelasticity

Two CFD techniques are assessed aiming at wind turbine aeroelasticity: a classic finite volume formulation to solve the Navier-Stokes equations, and a viscous-inviscid interaction formulation. Those 2 methods are tested with a NACA 63₄ – 421 airfoil, and both steady and unsteady numerical results are compared with experiments performed in the IAT wind tunnel. The Naviers-Stokes solver associated with the Wilcox k–ω turbulence model with SST corrections gives pretty good predictions for incidence in the range 0–15°, even for the static stall at 9°. The viscous-inviscid interaction solver provides results very close to the experiments for the whole range of incidence (0–30°). As far as unsteady simulations are concerned, both solvers give similar results. The computed lift evolutions versus incidence and excitation frequencies reproduce fairly well the experimental ones.