Aerodynamic performance of the gliding wing with slotted wing tips

Avian wingtips comprise a series of primary feathers. When birds such as raptors glide, these feathers form slotted wing tips. In this study, we modeled avian wings as a series of rectangular elements and evaluated their aerodynamic performance using both two- and three-dimensional numerical simulations. We compared slotted wings with those without slotted wing tips and found that the slotted configuration weakened the wingtip vortices, resulting in an increased lift-to-drag ratio. These findings offer valuable insights into the design of bioinspired flying robots and the evolution of avian wing morphology.