Numerical Analysis of Dimple Effect on Airfoils for varied AoA

Abstract

The main objective of aircraft aerodynamics is to enhance the aerodynamic characteristics and manoeuvrability of the aircraft. This enhancement includes the reduction in drag and stall phenomenon. The airfoil, which contains dimples, will have comparatively less drag than the plain airfoil. Introducing dimples on the aircraft wing will create turbulence by creating vortices, which delays the boundary layer separation resulting in decrease of pressure drag and increase in the angle of stall. In addition, wake reduction leads to reduction in acoustic emission. The overall objective of this study is to improve the aircraft manoeuvrability by delaying the flow separation point at stall and thereby reducing the drag by applying the dimple effect over the aircraft wing. This Study includes computational analysis of dimple effect on NACA 0018 airfoil. Dimple shapes of square selected for the analysis; airfoil tested under the inlet velocity of 30m/s at different angle of attack (12˚, 14˚, 16˚, 18˚,) for 8mm & 10mm diameter of Dimples. This analysis favours the dimple effect by increasing L/D ratio and thereby providing the maximum aerodynamic efficiency, which provides the enhanced performance for the aircraft.