Investigation of Aerodynamics Performance Towards Effect Separation Location on NACA 4415 Airfoil with Computational Method.

NACA 4415 is an airfoil commonly used in wind turbines and aircraft wing. This study uses computational method with type C grid with variations in grid elements 5×10², 5×10³, and 5×10⁴. From the grid independence test, grid with 5×10⁴ elements are the most suitable to get the best computational results. The turbulence model in this study is standard k-ε. From the computational results, the best Cl is found at the interval -9°≤ α ≤15°. In comparison, the best Cd is in the interval -7°≤ α ≤15°. Meanwhile, for Cm, the best data is obtained at the interval - 7°≤ α ≤10°, where the Cm gradient increases or decreases not too extreme. However, from Cl/Cd analysis, the best performance of NACA 4415 is at -7°≤ α ≤6°. Outside of that interval, the performance tends to decrease due to the influence of separation. Those are evident from separation point starting at α=11° where the position is in x/c=0.165, and as α increases, the position of the separation point will get closer to the leading edge. On the lower side of the airfoil, the separation begins to form at α=-11° and will get closer to the leading edge when the airfoil reduces α as in α=-15°. [ABSTRACT FROM AUTHOR]