An Airfoil Surface Modification to Promote Laminar-Turbulent Flow Transition

There are benefits of promoting a laminar-turbulent flow transition at low Reynolds numbers. It can increase the lift to drag ratio and create vortices that boost lift over the wings. It has been shown at large Reynolds numbers, greater than 6106, irregularities on the surface of an object can accelerate this transition. This presentation will experimentally examine how one can improve the aerodynamic performance of a stationary airfoil at low Reynolds numbers, between 104and 105, by adding roughness to the surface of an airfoil. The lizard genus Draco was used through biomimicry to develop surface modifications to be applied to a NACA 0012 airfoil. Hexagonal surface modifications modeling the lizard’s scales are tested at different locations along the cord length. High speed particle image velocimetry (PIV) measurements were taken to analyze the trajectory of vortex structures formed on the win.