Active wing deformation in natural organisms provides remarkable maneuverability in complex environments. While numerous studies have examined bioinspired morphing mechanisms, relatively few have systematically compared the principal morphing strategies employed across biological flight and swimming. This study investigates and compares the wake structures and force dynamics associated with fundamental structure-deforming submodes in biological wing motion. Five principal morphing submodes, including pitching, bending, extending, flapping, and twisting, are examined to characterize their aerodynamic performance. The results reveal unique frequency-dependent lift enhancements, where the bending mode provides superior lift at lower frequencies, while the pitching and twisting modes become more effective in lift enhancement at higher frequencies. However, drag remains relatively insensitive to frequency variations in both the bending and extending modes. The dynamic spectra exhibit prominent peaks at deformation frequencies and their harmonics, indicating strong structural implications on flow dynamics. As the deformation frequency approaches the flow passing frequency, the flow dynamics begin to be locked, leading to vortex uniformity and homogenization of the dynamic forces. These effects arise because structural morphing stabilizes vortex shedding, thereby suppressing the formation of secondary, irregular vortices. The wake modal analysis further indicates that the generation of leading-edge vortices leads to lift enhancement, and their reattachment to the wing surface tends to suppress lift burr-fluctuation. Furthermore, the superposition of specific submodes effectively enhances lift without increasing drag, providing new strategies for the design and control of future actively deforming airfoils.

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• Biological fluid dynamics
• Flying
• Swimming