Lift enhancement at low Reynolds numbers using pop-up feathers

The design of Micro Air Vehicles (MAV) is challenging since the aerodynamic efficiency of airfoils and wings decreases at low Reynolds-numbers. We seek to improve the performance of the airfoils using a passive flap on the extrado of the airfoil mimicking the deployment of feathers of a bird. We present force measurements of several airfoils at Reynolds-numbers of about Re 30,000 and Re=40,000. Copyright © 2009 by Nanyang Technological University.