Study on the flow instability of a morphing airfoil at low Reynolds number

Wei He (University of Liverpool)

Inspired by the motion of bird and fish, biofluid mechanics has already brought about aerodynamics design development. The modal instability is analysed for the low Reynolds number separated flow with two alternations in morphing NACA 0012 airfoil: a small bump on the upper surface and a flexible trailing edge. At certain flow conditions, the bump near the leading edge will destabilise the flow, and it will mitigate the stability as it closes to the trailing edge. At large angle of attack, the flexible trailing edge swinging downward will increase the stability, in contrast, the stability is suppressed with trailing edge swinging upward.