Numerical Simulation Of Aerodynamic Performance For Horizontal Axis Wind Turbine

As a clean renewable energy, the wind power attracts people's more attentions all over the world with the increasingly prominent of energy and environmental issues. Wind power in our country has been developed rapidly for recent 10 years. The horizontal axis wind turbine has been proved the most effective wind energy conversion devices. However, there are lots of problems to be solves concerning about wind power, in which aerodynamic is the basic one which is extensively solved by the traditional BME method and wind tunnel test data at present. Actually, these methods underestimate the wind power generated because of the rotating and the 3-D characteristic. With the development of modern computer technology and simulation method of 3D turbulence, CFD is playing more significant roles in studying aerodynamic performance.The 2D physical, mathematical models of the flows around the NACA63-215 airfoil which is mostly used on the traditional horizontal axis wind turbine were built. The numerical analysis is carried out using three-dimensional Navier-Strokes codes with the three turbulence model including Baldwin-Lomax, Spalart-Allmaras and k-εmodels for closure by the FINE/TURBO package of NUMECA commercial software. The calculations are performed with a central space discrimination scheme, the time depending method, and the classical Runge-Kutta algorithm of stage four. The technology of multiple grids was used to speed up the convergence. Isograms, distribution nephogram, vectograph, streamline and 2D curves were used to describe the movement. The conclusion can be drawn that Spalart-Allmaras turbulence model was more accurate.Then 3D physical and mathematical models of the flow around rotational blade were built in the rotational coordinate system based on the blade, and turbulence was computed by using Spalart-Allmaras model which had been proved to be more accurate in computing the aerodynamic performance of the airfoil. The combination of quantitative pressure distribution curves and qualitative limiting streamlines on the wall were used to show the results. The greater differences of static pressure distribution between the 2D and 3D results can be found by comparing the 2D model without rotating and the 3D rotating model and also can prove the existence of the phenomenon called static stall. The paper's study shows that, on the one hand, the aerodynamic characteristics of wind turbine blades have changed due to the role of the rotation, so to study the 3D rotation effect and the further understanding of their work have large value for the engineering; on the other hand, taking the CFD method as a complement and forecasting tolls for the experimental research is feasible. From the up words, the CFD method will certainly become a trend of development at wind turbine aerodynamic performance computing.