The Influence of Serrated Trailing-Edge Over NACA 0020 Airfoil at Different Turbulence Intensities

Abstract

To realize the intuition on how serrated trailing edge modifies the airfoil aerodynamics in a standardized manner, the current experimental work considers a NACA 0020 symmetrical airfoil exposed to the approaching flow with different turbulent intensity. The Reynolds number was adhered at Re = 3.4 × 105, whereas the turbulent intensity ranges from 0 to 5% is consider in this study. It is noticed that a thin serrated trailing edge can boost the lift, although it appears no series rise in drag. The serrated trailing edge is a mechanism that joined together to the wing at the trailing edge without changing the basic geometry favours ability to progress vast aerodynamic improvement. In addition, seeding turbulence to the flow shows an effect on delaying the stall angle to the extent of 5°. An increment in lift co-efficient along the linear region is also observed with an increase in turbulence intensity. At higher turbulence intensity, additional kinetic energy develops on the boundary layer along the suction side of the airfoil. This results to suppress the pressure fluctuation and in turn, a rise in lift to considerable extent, thus the serration on the trailing edge works as a flow control device.