| dc.description.abstract | In this study, computational fluid dynamics (CFD) simulations were performed using the Fluent and Mechanic module of ANSYS application to characterize the aerodynamic and static behavior of a horizontal axis wind turbine with a 43.2 m long blade. The blade geometry was chosen from NREL S-series, and it is 43.2 meters long and starts with a cylindrical shape at the root and then continues to the S818, S825, and S826 airfoils, which are used in NREL phase 2 and phase 3 wind turbines. This blade was modeled to be similar in size to a GE 1.5XLE turbine by Cornell University.
The focus of the first part of the study is to investigate the aerodynamic analysis of the wind turbine blade by using the Ansys Fluent module and to verify these findings using some physics formulas. Then, the pressure load obtained from aerodynamic analysis for velocities that varies between 8-20 m/s will be applied to the blade surface. In this way, the static performance of the wind turbine will be examined by calculating Von Misses stress and deformation on the blade for four different materials commonly used in the industry. Later, the effect of mechanical properties of materials on the static performance of the turbine blade will be highlighted.
Since it is not possible to access the geometries of the sample turbines due to confidentiality, and a certain blade-tower length ratio cannot be mentioned in the studies, the examples of wind turbines used in the industry are examined to determine the length ratio between the turbine blade and the tower. Later, the wind turbine tower is tried to be modeled according to ASCE (American Civil Engineering Association) standards for the offshore conditions. The design wind load calculated with the help of this standard was used in fatigue, buckling, and stress analyses in the Ansys Structural module.
Dynamic properties, one of the most important parameters in the preliminary design of the wind turbine tower, are mentioned in the last part of the thesis. The Baumeister Method was used to determine the natural frequency of the tower. The turbine operating frequencies, and the resonance criteria of the tower natural frequency were explained. Lastly, it will be observed whether the model of the turbine tower is suitable for the design load considering structural analysis and dynamic properties. | |
