Flow Induced Passive Fluttering of the Insect Wing

Insect wings exhibit a high frequency passive flutter in a steady streamline flow without the influence of muscle action. This study attempts to determine the relationships between passive wing fluttering and muscle-driven flight in insects from the orders Lepidoptera, Hymenoptera, and Odonata. To recreate the conditions of steady flight, we exposed tethered insects to flow from a wind tunnel with chord-based Reynolds numbers ranging from O(10³) to O(10⁴). The active wing beat frequency and passive flutter effect were measured using high speed cameras. Analysis of this data potentially reveals insightful information regarding morphologically based passive influences on the kinematics of insect flight.