Numerical investigation of geometrical corrugation influence to vortex flowfields at low Reynolds number

Corrugated wings, which are cross-sectional shapes of dragonfly wing, are expected to improve aerodynamic performance due to vortices generated by irregular shapes at low Reynolds number region. It is difficult to observe the influence of vortices generated from the unevenness of the shape by experiments. In this research, the flowfields around corrugated wings were calculated using Cartesian mesh-based Computational Fluid Dynamics (CFD), Building-Cube Method (BCM). The simulation grasped the detailed flowfield, which was difficult to be visually observed by the experiment. From the visualization result, it is found that the flow circulation velocity inside the concave and convex surface is not accelerated but slow. The result indicates that the improvement in aerodynamic performance is caused by the shape and position of unevenness.