Darrieus tipi bir rüzgar türbininin art izi karakteristiklerinin incelenmesi

It is essential to investigate turbine behaviors and wake characteristics of vertical axis turbines in different working situations in a systematic way. In this reason two different H-rotor Darrieus type vertical axis wind turbines was investigated using ANSYS Fluent software by two dimensional and three dimensional computational fluid dynamics simulations. First turbine was a two NACA0018 bladed reference turbine for validation which was studied before both experimentally and numerically. Second turbine was a three NACA4418 bladed prototype. The dimensions of the domains depend on the diameter of the turbine and chord lenght which was derived from similar studies in the literature. Turbulence model k-ω SST is used to solve time-dependent Reynolds-Average-Navier-Stokes equations in unsteady simulations. Continuity and momentum equations was solved with SIMPLEC algoritm. Different parameters such as mesh independency, time step sizing, third dimensional effects on turbine performance and wake formation in near and far wake in various operating conditions were investigated. Two and three dimensional computational analysis were performed on reference turbine and near and far wake behaviours were investigated. Three dimensional computational analysis were performed on prototype turbine and performance characteristics on different conditions and near wake behaviours were examined. Turbine behaviors in different free stream wind speed conditions and rotational speed conditions were compared.