High-fidelity simulations of hummingbird escape maneuver

Hummingbirds are extremely agile among the flying animals. In this study, we reconstructed the full-body kinematics of the escape maneuver from high-speed videos of a hovering hummingbird when it was startled. The reconstruction includes both wings, head, trunk, and the tail motion. The kinematics was then incorporated into the 3D CFD simulation using a parallel immersed-boundary method. From the flow simulation and force analyses, we will identify the critical forces that allow the bird to perform such a rapid maneuver sequence, including pitching backward, rolling, and accelerating, etc. In addition, we will discuss the unsteady aerodynamics involved in the two wings. Project is funded by the ONR.