Aeroelasticity of 2-D lifting surfaces with time-delayed feedback control

Two basic issues related to the open/closed-loop aeroelasticity of 2-D lifting surfaces in an incompressible flow field are considered. These concern the subcritical aeroelastic response to external time-dependent excitations, and the flutter instability of actively controlled airfoils involving a time-delayed feedback control. Results and comparisons regarding the flutter instability obtained via the first Volterra kernel in conjunction with a frequency eigenvalue analysis are presented. In the same context, the implications on the instability boundary and aeroelastic response of the presence of time-delays in the feedback control are investigated and pertinent conclusions are supplied.