Flutter Behaviour of an Adaptive Transonic Wing

Kurzfassung

The influence of small local contour deformations (bumps), which are applied for shock control, on unsteady aerodynamics and aeroelastic stability is investigated numerically. First the mechanism of bumps and their impact on shock dynamics is outlined for the supercritical NLR7301 airfoil. The bump yields more complexity of shock dynamics for low frequency oscillations and a moderate change of lift and moment coefficients. For the 3D AMP Wing flow conditions with different lift values are investigated. 3D bumps for cases with a promounced shock can reduce the total steady drag by 3 to 6%, but may also change the flutter boundaries significantly. Applied aerodynamic CFD methods are based on linear and nonlinear potential theory. They are very fast and able to predict stability boundaries in good agreement with those from windtunnel tests for nonseparated transonic flow.