Akademik Veri Yönetim Sistemi
32nd Congress of the International Council of the Aeronautical Sciences, ICAS 2021, Shanghai, Çin, 6 - 10 Eylül 2021, (Tam Metin Bildiri)
Wing rock is a highly nonlinear undesirable phenomenon involving lateral directional instabilities at higher angles of attack and subsonic speeds. This study investigates the wing rock phenomenon on a rectangular wing of aspect ratio two and Reynolds number of 100,000. These conditions are typical of fixed-wing Micro Air Vehicles (MAV). The experimental study, conducted in a low-speed wind tunnel, successfully captures wing rock through free-to-roll experiments. In the vicinity of the stall, the onset of wing-rock was observed. To further the investigation, a numerical study is conducted to find the static and dynamic stability derivatives in a roll from 0° to 30° angle of attack and a reduced frequency of 0.0346 through forced roll oscillations of 40° amplitude. The conditions of wind-tunnel tests are replicated in numerical simulations. The forced roll oscillations on the rectangular wing were implemented through the sliding mesh technique in a commercial CFD solver. The loss in roll moment damping, a sufficient condition of wing rock, was observed in the vicinity of the stall. The flow physics of the vortex dynamics revealed that the wing rock phenomenon starts to occur due to the bursting of the side tip vortex and its interaction with the leading edge separated vortex around the stall.