On modeling of piezoelectric patches in aeroelastic vibrations

A procedure for the analysis of the effectiveness of shunted piezoelectric devices in increasing passive damping on aeroelastic systems is presented. The proposed methodology is based on the description of aeroelastic systems composed by a flexible fixed-wing in a linear potential flow bonded with several piezoelectric devices in order to achieve a selective control of critical aeroelastic modes. The aeroelastic application has shown the capability of improving the stability margin and reducing the response amplitude in the parametric operative range of the system assigned in term of flight speed, air density, and Mach number. Indeed, a relevant issue emphasizing the complexity of the aeroelastic vibrations is represented by the explicit parametric dependency of the system to such parameters. Thus, a suitable performance of the piezo damper should be designed for any flight speed, altitude and Mach number. Moreover, a control law has been used for the optimal tuning of piezo devices within the parameters ranges by means of a resistive-inductive shunt of such devices. The modal model, the stiffness matrices of piezo elements and also the aerodynamic model have been calculated by a commercial finite element code. The use of a finite-state form for the aerodynamics allows to get the solution of the problem by a standard first-order state-space representation.