Investigation into the aerodynamic interference mechanism between wing and tail for bionic flapping-wing aircraft

Unsteady wing–tail interactions strongly dictate the aerodynamic performance of tailed flapping-wing aerial vehicles. This study employs three-dimensional unsteady computational fluid dynamics (CFD) to elucidate the effects of wing taper ratio and spatial tail positioning on overall aerodynamic characteristics. By modeling the wings as rigid structures with constant projected area and wingspan, the chordwise distributions and tail locations are systematically varied. Numerical results reveal that wings with smaller taper ratios yield an 11.71% increase in time-averaged lift compared to larger taper ratio configurations, exhibiting superior unsteady lift generation. Furthermore, locating the tail slightly downstream of the wing trailing edge and elevated above the wing plane maximizes mean lift and increases the time-averaged pitching moment by approximately 5.85% relative to the coplanar layout. Finally, flight tests of a 76.5 g physical prototype at a 4 Hz flapping frequency successfully demonstrate macroscopic flight feasibility, confirming that the simulated total lift ( ∼ 120 g) provides a sufficient aerodynamic margin over the actual vehicle weight. These findings enhance the understanding of wing–tail aerodynamic coupling and provide robust layout design guidance for flapping-wing micro air vehicles.