Insect wing flexibility improves the aerodynamic performance of small revolving wings

Area of Science:

• * Biomechanics and insect flight dynamics.
• * Aerodynamics and fluid mechanics of biological systems.

Background:

• * Insect wings exhibit passive elastic deformation during flapping flight.
• * Understanding the adaptive significance of wing flexibility is crucial for explaining flight efficiency.

Purpose of the Study:

• * To investigate the adaptive value of insect wing flexibility using a revolving wing setup.
• * To determine how wing flexibility affects lift coefficient and flow separation in relation to wing size.
• * To explore the intra-specific tuning of wing flexibility through changes in wing-vein morphology.

Main Methods:

• * Utilized a revolving wing setup to simulate insect flight aerodynamics.
• * Compared the performance of flexible insect wings ( *Batocera rufomaculata* beetle) with rigid propeller blades.
• * Analyzed flow fields and turbulence activity beneath the wings to assess flow separation.

Main Results:

• * Wing flexibility suppresses the expected reduction in lift coefficient with decreasing wing size.
• * Smaller wings exhibit proportionally larger chordwise deformations due to intra-specific scaling of flexibility via vein cross-section.
• * Elastic deformations passively control flow separation as a function of angle-of-attack.

Conclusions:

• * Wing flexibility is a key factor in maintaining aerodynamic performance across different wing sizes.
• * Passive elastic deformations in insect wings play a significant role in flow control.
• * This mechanism enhances flight efficiency without requiring active neural control or feedback.