ACTIVE WING FLUTTER SUPPRESSION USING A TRAILING EDGE FLAP

The aeroservoelastic behaviour of a thin rectangular wing with a controllable trailing edge flap is investigated. A rather high aspect ratio motivates a numerical model based on linear beam theory for the structural dynamics and strip theory for the unsteady aerodynamic loads. Experimental flutter testing shows good agreement with the numerical stability analysis, and the impact of the trailing edge flap on the dynamics is verified by open-loop testing. The problem of stabilizing the wing utilizing the trailing edge flap is posed, and the design of a fixed-structure feedback controller is performed using numerical optimization. The problem of maximizing closed-loop modal damping with constraints on actuator performance is solved for a sequence of flow speeds and the obtained controller is synthesized using gain scheduling. The fairly large predicted increase in critical speed is experimentally verified with satisfactory accuracy.