A 3D-DDES numerical simulation of jet blowing as a power enhancement technique applied to a wind turbine with S809 profile

The aerodynamic performance of the NREL Phase VI wind turbine is investigated through the use of the blade element momentum (BEM) theory and computational fluid dynamics (CFD). The baseline configuration, consisting of a S809 airfoil, is modified to employ trailing edge blowing technology, an active circulation control technique known as Coanda Jet. Calculations are performed via 3D Delayed Detached Eddy Simulation (DDES) to solve the three-dimensional flow structures over the airfoil correctly. A preliminary campaign of simulations is first conducted for a wide range of angles of attack from α = 0° to α = 20° on an airfoil with chord c = 0.482 m with a wind speed equal to 29.3 m/s, which corresponds to the chord at 75% of the blade radius and the relative wind velocity it experiences respectively. Results are confronted with experiments to validate the model. Once mesh fidelity is proven, five different radial positions along the blade are considered and simulations are performed with and without jet blowing to prove its efficiency. Results show that lift and thrust force both increase, enhancing net power generated by the wind turbine, which is calculated via BEM.