Research On Mechanical Modeling And Its Aerodynamic Characteristic Of Circular-arc Airfoil Blade

Wind power is the next most mature technology and the most promising large-scale development of renewable energy.With the growing tension in the energy supply environmental and pollution is worsening situation,more attentions are paid to the development of wind power.Wind vane airfoil and aerodynamic characteristics are fundamental factors that determine wind turbine power performance and aerodynamic load characteristics.The theoretical analysis is an important method for the study of aerodynamic characteristics of the blades,and the mechanical model is an important method of theoretical analysis.In this paper,An circular-arc mechanics model is established to calculate the mechanical blade force.compared with the previous experimental results and CFD results were analyzed to verify the accuracy of the model.At last,using the final results of mechanical model to study arc airfoil aerodynamic characteristics.It is extremely difficult to establish a wind turbine complex airfoil blades mechanical model directly.First,to study a simple circular-arc airfoil blades,as the study of complex wind turbine airfoils foundation.Use the classical Joukowski Conformal Mapping into a circular-arc of the other plane,and using polar coordinates type of displacement,velocity is converted to polar coordinates type.Based on this,the blade portion of the force into circulation,no-circulation,and suction force.The three parts of the force is superimposed total blade force,the total force is divided by the normal force,lift and drag.The results obtained with the lift NACA4412,A18,F18 airfoil static contrast,the attack Angle of lift expressions settings and change the attack angle in the literature,as to obtain the unsteady lift curve,the results of the comparative literature.By comparing static and unsteady,and verify the accuracy of the model.By comparing model results with certain accuracy,the force applied to study the blade.Calculated using the results to study the aerodynamic characteristics of the blades,and by changing the curvature of the arc,study the effects of different curvature of aerodynamic characteristics.The results show that the arc upward bend,different curvature of aerodynamic characteristics.The results show that the arc upward bend,with the increase of the degree of bend,is larger than the lift in the same time period.When the arc bent downward with increasing degree bend,lift is smaller than the same time period.In this paper,the research methods used in the mechanical model,lay the foundation for future study of complex wind turbine blade airfoil,and find a new way to study other turbo-machinery blade.Use mechanical model study from the perspective of theoretical analysis of wind turbine blade stress practical feasibility,can compensate for the lack of theoretical research blade force,for the analysis of the aerodynamic characteristics of the blades,to improve unit efficiency and increase blade life,to ensure safe and stable operation of wind turbines,has a very positive meaning.