Numerical Analysis of NACA64-418 Airfoil with Blunt Trailing Edge

Abstract

The aerodynamic performance of blunt trailing edge airfoils was investigated. The flow fields around the modified NACA64-418, which consists of the tip blade of the wind turbine and Mexico model of IEA wind, were analyzed. To imitate the repaired airfoil, the original NACA64-418 airfoil, a cambered airfoil, is modified by the adding thickness method, which is accomplished by adding the thickness symmetrically to both sides of the camber line. The thickness ratio of the blunt trailing edge of the modified airfoil, tTE /tmax, is newly defined to analyze the effects of the blunt trailing edge. The shape functions describing the upper and lower surfaces of the modified NACA64-418 with blunt trailing edge are obtained from the curve fitting of the least square method. To verify the accuracy of the present numerical analysis, the results are first compared with the experimental data of NACA64-418 with high Reynolds number, Re=6×10 6 , measured in the Langley low-turbulence pressure tunnel. Then, the aerodynamic performance of the modified NACA64-418 is analyzed. The numerical results show that the drag increases, but the lift increases insignificantly, as the trailing edge of the airfoil is thickened. Re-circulation bubbles also develop and increase gradually in size as the thickness ratio of the trailing edge is increased. These re-circulations result in an increase in the drag of the airfoil. The pressure distributions around the modified NACA64-418 are similar, regardless of the thickness ratio of the blunt trailing edge.

Aerodynamic Performance Analysis of a Modified Joukowsky Airfoil: Parametric Control of Trailing Edge Thickness

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Numerical Investigation of Multi Airfoil Effect on Performance Increase of Wind Turbine

“…Numerical Analysis of NACA64-418 Airfoil with Blunt Trailing Edge was conducted and obtained results were compared with experimental data validate simulation accuracy of CFD then other airfoil were investigated. The transport equations for the transition of SST model is based on the Wilcox k-ω model, is good to predict the transition point [6]. The numerical simulation of horizontal axis wind turbines airfoil S809 with untwisted blade was performed with k-ε model and compared with experimental data to determine the optimal angle of attack that produces the highest power output [7].…”