Active control of flutter in compressible flow and its aeroelastic scaling

A new two-pronged approach suitable for the general aeroelastic and aeroser voelastic scaling of any aeroelastic configuration is presented. The method produces aeroelastic scaling laws for general configurations, and it is pa rticularly useful for situations involving active controls and smart-materi als-based actuation. This approach is illustrated by applying it to a two-d imensional wing section in compressible how, combined with a trailing-edge control surface. Augmented aerodynamic states are reconstructed using a Kal man filter, and linear optimal control is used to design a full-state feedb ack flutter suppression controller. Constraints on actuator deflection and rate are also considered. In a second example, flutter suppression for a ty pical cross section with a conventional trailing-edge control surface is co mpared with that obtained with piezoelectric actuation utilizing bend/twist coupling.