Stability of a time-delayed aeroelastic system with a control surface

This paper investigates the effects of time delay on the flutter instability of an actively controlled airfoil in an incompressible flow field. Firstly, in view of the presence of time delays in the actual control system, multiple time delays in feedback loop are introduced to the present flutter suppression system. Next, the stability boundaries of the closed-loop system with multiple time delays are obtained by solving a polynomial eigenvalue problem, and are validated by numerical simulations. The results demonstrate that time delays in control loop have strong effects on the stability of controlled aeroelastic systems and should not be ignored in the design of the aeroservoelastic system of the aircraft.