Enhancing the aerodynamic performance of fling kinematics through wing deformation and phase overlap

The study investigates the impact of wing deformation in insects employing clap-and-fling kinematics specifically during the peel phase. In this regard, the curvature parameter ( γ ) is introduced to mimic bending patterns observed in fruit flies, while the sweep-pitch overlap ( ξ ) is also explored. Numerical simulations performed using an in-house solver reveal complex and intriguing interactions between wing deformation, overlap, and vortex dynamics. Increasing wing deformation enhances mean lift, despite a delayed leading edge vortex (LEV) pair formation. Unlike lower curvatures, where circular LEVs remain attached, higher γ produces detached, non-circular LEVs, expanding the low-pressure region across the entire chord. However, excessive wing straightening at high γ and wing-wake interaction disrupt new LEV formation also responsible for lower lift toward the end of peel. Mean lift increases with overlap due to stronger vortex-pin structures extending from root to tip, diminishing the high-pressure region near the trailing edge. The deforming wing's Pareto front achieves significantly higher lift with lower input power, enhancing fling aerodynamics and reveals ideal range of γ and ξ that maximize lift. These findings emphasize the importance of LEV and trailing edge vortex dynamics in efficient lift generation during wing deformation, offering insight for bio-inspired flapping-wing designs. © 2025 Author(s).