Suppressing aeroelastic vibrations via stability region maximization and numerical continuation techniques

An active flutter suppression using linear sub-optimal control scheme is investigated for a 2dof airfoil system with nonlinear torsional stiffness and limited deflection amplitude of its single actuator. The suppression of limit cycle oscillations in the nonlinear closed-loop system is achieved through maximization of the stability region of its linearized system. The critical value of the control input amplitude is determined via numerical continuation of closed-loop limit cycle. At this value, the cycle experiences saddle-node bifurcation and disappears, satisfying the necessary condition for the global stability in the closed-loop system.