Investigation of different blade profiles for high-capacity wind turbines by cfd method

Nowadays, CFD simulations for wind turbines focus on numerical simulations and model-based optimizations at the turbine scale. In this study, the dimensions of the blades and some main parts of the turbines to be manufactured with two different airfoils (such as NACA 2414, 4415) for different large turbine powers (10, 25 and 50 MW) are designed. The design calculations and CFD analyses of each turbine were performed for nominal wind speeds of 11-14 m/s. By dynamic analysis of the turbine in motion, the blades that carry more wind load and are more efficient in wind energy production are analysed by CFD method. In the thesis, the selection of suitable blades and other main parts for wind turbines with large and medium loads in terms of efficiency, annual electrical energy production amount, wind loads on the blade and turbine is taken as the basis of research. The reference large wind turbine serves as a model for selecting the airfoils. When designing large wind turbines, the blades are first designed and the flow analysis and optimal selection are studied in detail. In the 10 MW wind turbine, the turbine with the NACA 4415 profile achieves the highest energy production at a wind speed of 11.5 m/s. In contrast, the wind turbine with the NACA 2215 profile achieves the highest energy production at a wind speed of 14.5 m/s. For a 50 MW wind turbine, it was found that the blade length would be 250 m, the weight would be around 480-500 tons and the rotor rotation speed should be 0.2-0.8 rpm to avoid high centrifugal forces. When the forces on the blades designed from both NACA profiles were analysed, it was found that the part of the blade 15% away from the hub was the most vulnerable in terms of strength. It was concluded that this part of the wing should be reinforced with lighter and stronger materials than glass fiber, such as carbon fiber.