Modelling Piezoelectric Actuation During Structural Flutter

Aeroelasticity is a major concern in structural control. It results from the interaction between the air-stream and the structure. Wing flutter is a well known problem of the aero-elasticity. It occurs when the two lowest system eigenvalues (plunge and pitch motion) coalesce at a certain air speed known as the flutter speed. The increasing use of active material induced-strain actuation such as piezoelectric materials in the suppression of structural vibrations has seen its extension to wing flutter control. Higher flutter speed and hence, a wider operating envelope was achieved by delaying the coalescence of these two eigenvalues. This delay is obtained by adding more strain energy to the system as a result of the activation of the piezoelectric actuators. This paper models a simple beam under nominal aerodynamic loading conditions for the determination of analytically-derived onset of flutter speeds. Also shown in this paper, is the effect of orientation of actuated piezoelectric patches, on the shift of the flutter speed.