CFD Investigation of the Far Wake and Power Prediction of a DARRIEUS Wind Turbine

The aim of the present paper consists in predicting the generated far wake by a small DARRIEUS wind turbine, the power coefficient variation with the tip speed ratio is carried out as well. The Unsteady Reynolds Averaged Navier–Stokes equations are solved numerically using a dynamic mesh technic according to rotational speed of the wind turbine. The CFD open source code (openFoam), based on the finite volume method, is used for the numerical computations where the SST k-ω turbulence model is employed. The power coefficient is calculated for different values of the tip speed ratio λ according to the numerically computed torque, where the maximum value reach 0.34 at λ = 1.5. The numerical results show an increase of the resulting vorticity enhanced by the increase of λ.