We propose to develop and test a computationally efficient method of predicting and controlling dynamic loads and nonlinear unsteady aeroelastic effects. The proposed method provides a rational design tool for the prediction and control of resonant fluid-structure interaction without compromising the effects of shocks, viscosity separation, and shock-boundary layer interaction. Stability of the coupled fluid-structure system is accurately predicted in an eigenvalue formulation where eigenvalues correspond to coupled-system nodal frequencies in the time domain and their growth rates. New technology provides robust and scalable computation techniques that can solve Air Force problems. Rigorous design of coupled flow and structural control follows natural1y. To validate the computational method, and to develop active control systems, we will design an adaptive pitch-and-plunge apparatus (PAPA) for wind tunnel testing. The apparatus will allow the technician to dial in structural stiffness (and therefore structural nonlinearities). This will permit an investigation of limit cycle oscillations (LCO's), bifurcations, and hysteresis associated with structural non-linearities and bi-linearities. The experimental model will enable testing over a wide range of structural states without the expense of model change-outs, and it provides an ideal test bed for an investigation of structural control including aeroservoelasticity (wing warping)
