Aeroelastic Response of a Flexible Delta Wing Due to Unsteady Vortex Flows

Aeroelastic response of a flexible delta wing due to the unsteady vortex flows was investigated in a wind tunnel. It was found that maximum rms buffeting occurs when vortex breakdown is close to the apex of the wing. The rms acceleration drops very rapidly in the vortex shedding regime at higher angles of attack. The dominant modes of vibration are the second and third modes when vortex breakdown is over the wing. In the case of the full-model delta wing, vortex breakdown produces the largest aeroelastic response, and the dominant mode is the second antisymmetric mode. Hence, there is evidence of a coupling between the wing structure and unsteady vortex pair interactions, which was surprising at this relatively low sweep angle of Λ=60°.