Aerodynamic consequences of wing damage in dragonflies

TL;DR

This study uses CFD simulations to analyze how wing damage in dragonflies affects aerodynamic forces, revealing complex flow changes and wing interactions that impair flight performance.

Contribution

It provides new insights into the aerodynamic effects of wing damage and wing-wing interactions in dragonflies through detailed CFD analysis.

Findings

Wing damage reduces aerodynamic force production.

Flow field alterations explain performance decline.

Forewing damage impacts hindwing aerodynamics due to wing interaction.

Abstract

Flapping wings are the primary means by which dragonflies generate forces, but they are susceptible to damage due to their inherent fragility. The damage results in a reduction in wing area and a distortion of the original wing, which in turn leads to a decline in flight ability. Furthermore, the flows of dragonfly fore- and hindwings exhibit an interaction, thus damage to the forewing can also impact the aerodynamic performance of the ipsilateral hindwing. In this study, we examine this problem through CFD (computational fluid dynamics) simulations on a series of damaged dragonfly fore-/hindwing models according to the probability of area loss from the literature. The flow fields and aerodynamic forces for the different damaged wing cases are compared with those for the intact wings. This comparative analysis reveals how the different patterns of wing damage modify the vortex structures around the flapping wings and lead to a drop in aerodynamic force production. The causes behind the diminishing aerodynamic performance are shown to be subtler than the pure area loss and are regulated by the changes in the flow field that result from wing damage. Wing-wing interaction becomes particularly important when forewing damage occurs.