Aerodynamic Forces and Wake Analysis of Wing Damaged Flapping Flight

Flapping flight is a commonly used mechanism of micro aerial vehicles and insects alike. Dragonflies use their four-winged anatomy to navigate the environment, maneuver around obstacles, and perform other essential flight patterns. The flight performance and aerodynamics of intact flapping wings is well known; however, this study aims to clarify how wing damage affects the flight performance. First, high speed videos of the damaged wing flight, a takeoff performed by a dragonfly, is captured, and subsequently digitally reconstructed to create a three-dimensional model. Second, using an immersed-boundary method (IBM) based incompressible Navier-Stokes direct numerical simulation (DNS) solver, we resolve the aerodynamic forces and wake topology of the dragonfly’s damaged wing flapping flight in high detail. We found that spanwise damage doesn’t cause any detriment to the force capabilities of the damaged wing which is due to increased pitch angles of the damaged wing. As a consequence, fliers with spanwise damaged and intact wings may be able to utilize similar strategies to achieve takeoffs. The wake topology of the wing damaged flight is also examined. This work serves as a baseline for studying the effect of wing damage for flapping flight and could provide useful insights to micro-aerial vehicle (MAV) designers as some degree of wing damage may be an inevitable occurrence for winged fliers.