Reduced-order aerodynamic model and its application to a nonlinear aeroelastic system

Starting from a finite state model for a two-dimensional aerodynamic now over an airfoil, the eigenmodes of the aerodynamic now are determined. Using a small number of these aerodynamic eigenmodes, i.e., a reduced-order model, the aeroelastic model is formed by coupling them to a typical section structural model with a trailing-edge flap. A free-play nonlinearity is modeled. Results are shown from the finite state model, the reduced-order model, and previous theoretical and experimental work, All results are in good agreement.