Chaotic motions of an airfoil with cubic nonlinearity in subsonic flow

The aeroelastic response of a 2-degree-of-freedom airfoil placed in subsonic flow with cubic nonlinearity in pitch has been investigated using an Runge-Kutta (RK) method. The equilibrium point is not located at the zero point, and a mixed region of periodic and quasi-periodic motions dominates the bifurcation diagram. The system's behavior changes irregularly between periodic and quasi-periodic motions. The results show that both the stable equilibrium point and the type of limit circle oscillation are also very sensitive to initial conditions. Price and colleagues have proved that there is a period-doubling route to chaos with the velocity increasing.