Experimental Investigations of an Aeroelastic Wind Tunnel Model for Tail Buffeting Analysis

Modern high-agility aircraft are often affected by buffeting phenomena. At higher angles of attack, vortex bursting results in a strongly unsteady flowfield downstream of the breakdown region. High turbulence intensities and their distinct frequency content lead to structural dynamic excitations of the wing and downstream located elements such as tailplanes, potentially causing structural damage and degraded handling qualities. A full-span wind tunnel model was developed for the experimental analysis of buffeting effects. To achieve elastic structural properties, the wings and the horizontal and vertical tailplanes are 3D-printed from polylactide. As a quasi-rigid reference case, aluminum components can be mounted on the modular model configuration. In the context of this work, the aerodynamic characteristics and aeroelastic phenomena are investigated experimentally. Similarities and differences between quasi-rigid and elastic model components are highlighted for forces and moments and unsteady surface pressures. In the rigid configuration, vortex bursting occurs farther upstream, resulting in increased pressure fluctuations and higher buffet peak amplitudes at lower angles of attack compared to the aeroelastically scaled configuration. At higher angles of attack, the eigenmodes of the aeroelastically scaled vertical tailplanes coincide with the dominant buffet-associated frequencies.