Aerodynamic Performance of a Tandem Wing Configuration Inspired from Dragonfly Gliding Flight for MAV Application

The design of micro air vehicles (MAVs) involves optimizing aerodynamic performance challenges due to the small size and, consequently, the low Reynolds number (O(104–5)). MAVs are often inspired by the flight capability of insects and birds; and are mimicked for the design of MAVs. The dragonfly frequently uses a gliding flight mode relative to the other small fliers and operates at a range of O (102–4). The literature suggests that the corrugated profile improves the aerodynamic efficiency around Reynolds number at 104. It allows us to investigate the aerodynamic advantages of tandem corrugated airfoil inspired by the dragonfly wing. In this paper, we perform direct numerical simulations of flow past bio-inspired corrugated wing to understand the impact of the tandem wing configuration. The horizontal distance between the wings is fixed, and the vertical distance varies. The results reveal that the forewing/hindwing interaction increases the lift of the forewing relative to the isolated wing for all the case studies. The combined drag coefficient drops by ≈ 7%, and overall efficiency drops by ≈ 13% relative to an isolated wing for a case study with zero vertical spacing between forewing and hindwing at 3° angle of attack, fixed for both wings. With no vertical gap, the aerodynamic efficiency matches close to the isolated wing with the decrease in tandem wing combined drag coefficient compared to an isolated wing.