The Experimental Analysis, And Optimal Design Of Of Dedicated Airfoil Family For Horizontal-Axis Wind Turbines

With development of wind turbines, traditional aviation airfoils can not meet the requirement of wind turbine airfoils which are differ from traditional aviation airfoils in choice of design point, off-design characteristics and structure properties, so it is very important to design wind turbine dedicated airfoils. Some European and American countries have been researched on the wind turbine dedicated airfoils, but China haven't had a mature wind turbine airfoil family.According the content of the National 863 project "Design and Experimental Research on Advanced Wind Turbine Dedicated Airfoil Families", analyzing the wind tunnel result of the CAS-W1-XXX thin airfoil family, comparing the result with other airfoils. The wind tunnel results show that the CAS-W1-XXX thin airfoil family has good insensitivity to leading edge roughness, high max lift coefficient and good stall characteristics. In addition, optimizing the CAS-W1-XXX thin airfoil family base on the original design, the max Cl/Cd of new airfoil family increased.For meeting the development of the wind turbine becoming larger and larger, according to the aerodynamic and structural requirement of airfoils for horizontal-axis wind turbines, designing the CAS-W1-XXX thick airfoil family which thickness-to-chord range from 30% to 60% chord with the direct method. In the design of the thick airfoil family, limiting the upper surface thickness,S shape aft loading and increasing trailing edge thickness to make airfoils insensitive to leading edge roughness, and trailing edge airfoil can improve the aerodynamic characteristics and the structure stiffness. The trailing edge thickness ranges from 0.05% chord to 3% chord. Turbulent separation occurs on pressure surface at small attack angles for the airfoils which relative thickness more than 40%, making airfoil stall at small attack angles and the lift coefficient decrease. Increasing the trailing edge thickness and decreasing the thickness of the pressure surface to eliminate the separation in this paper, the max trailing edge thickness is 11% chord. The aerodynamic characteristics improve remarkably after optimizing.