A DESIGN OF A LOW-REYNOLDS NUMBER AIRFOIL THAT LEADS TO THE FORMATION OF SEPARATION BUBBLES AT THE LEADING EDGE

Abstract

The aerodynamics of airfoils at low Reynolds numbers (Re) has become increasingly important from both fundamental and industrial points of view, due to recent developments in small wind turbines, small unmanned aerial vehicles (UAVs), micro-air vehicles (MAVs), as well as researches on bird/insect flying aerodynamics. Researchers on airfoil aerodynamics have focused on conventional aircraft design with Re beyond 5×105, where separation bubble forming on the leading edge has positive impact on aerodynamic performance of the airfoil, increasing the lift coefficient. Separation bubble however does not form at low Re (<1.0×104), hence the value of lift coefficient is small. Source panel method is used to explore performances of several geometry characteristics of 2-D airfoil. It is made possible by varying the maximum thickness, maximum camber and position of maximum camber to obtain different airfoils and their lift and drag coefficient computed. Reynolds numbers considered here are 1000 to10, 000. It is from the study that a desired airfoil is found that has high lift coefficient and leading edge separation. In this study, it is now possible to design airfoil that can work well at low Reynolds number that is where velocity is low.