Name : [in Japanese]
Date : March 15, 2024 - March 16, 2024
In order to investigate the relationship between the shape and aerodynamic characteristics of a corrugated airfoil with two valleys in the low Reynolds number region, the lift-drag ratio was measured by varying the airfoil thickness and visualizing the flow. At Re = 4.0 × 104, the maximum lift-drag ratio was 1. 4 times higher for the thick airfoil and 1. 6 times higher for the thin airfoil compared to the streamlined airfoil. For both types of airfoils, a stable circulating flow was formed in the valley at low angles of attack, along which the flow from the upstream top of the convex part flowed to the downstream airfoil surface, thereby increasing the lift. As the angle of attack increased, there was a backward flow from the second valley to the first valley, and the mainstream flow stalled away from the airfoil surface.