Experimental and Numerical Study of Forward Flight Aerodynamics of Insect Flapping Wing

Abstract

Experimental and numerical studies are conducted on the aerodynamic characteristics of a flapping wing of an insect in forward flight. Unsteady aerodynamic forces and flow patterns are measured using a dynamically scaled mechanical model in a water tunnel. The design of the model is based on the flapping wing of a bumblebee. The forces and flow patterns are also computed using a three-dimensional Navier-Stokes code. Comparisons between the experimental and numerical results show good agreement in the time histories of aerodynamic forces and flow patterns in both hovering and forward flight. Aerodynamic mechanisms of a flapping wing in forward flight, such as delayed stall, rotational effect, and wake capture are examined in detail. The results indicate that these aerodynamic mechanisms had an effect on the aerodynamic characteristics of the flapping wing in forward flight; however, these mechanisms function differently during the up- and downstroke, for different stroke plane angles, and for different advance ratios.