Experimental study about the deformation and aerodynamic characteristics of the passive morphing airfoil

Abstract

In order to investigate the deformation and aerodynamic characteristics of the morphing airfoil model passively deformable by the dynamic pressure, two-dimensional wind tunnel experiment was conducted. The trailing edge portion (0:3 ≤ x=c- ≤ 1:0) of the model was made of flexible materials so as to be deformable by the dynamic pressure without using any actuator. The upper and lower surfaces were connected by spokes inside the airfoil. The aspect ratio of the model was 1.0 and the Reynolds number based on the chord length was 1.78 © 105 in the wind tunnel experiment. The deformed geometries were measured optically, and the lift coefficient was measured with a force sensor. The morphing airfoil deformed to increase its camber in the high angle-of-attack, and this deformation caused higher lift coefficient than that of the rigid airfoil. Also, by the measurement of Cp distribution around the rigid airfoil and the morphing airfoil, it was found that the morphing airfoil had larger difference of pressure between upper and lower surface than the rigid airfoil in the trailing edge portion.