Tarcísio Marinelli Pereira Silva

Energy analysis of semi-passive control for an aeroelastic plate-like wing using shunted piezoelectric materials:

The use of piezoelectric materials in vibration control problems has been widely investigated over the last years. The main control techniques using piezoelectric materials are the active and passive ones. In the particular case of aeroelastic control, passive piezoelectric networks have a weak capability of improving the flutter envelope. Although active systems can achieve good control performance, the potential large amount of power required for actuation is an important issue. The synchronized switch damping techniques were developed to overcome the drawbacks of passive and active control. These nonlinear techniques increase the electromechanical conversion and enhance the shunt damping. In this article, an energy flow analysis is employed to investigate the effects of two switch damping techniques on the aeroelastic behavior of a plate-like wing in two case studies. In the first one, the energy flow analysis is presented for the base excitation condition without aerodynamic influence. The working principle of switch damping techniques and the energy return phenomenon are discussed. In the second case, the energy flow analysis is employed to discuss the aeroelastic evolution and semi-passive control effects over a range of airflow speeds.

Passive and hybrid piezoelectric circuits to reduce induced-atmospheric turbulence vibration of a plate-like wing

Different methods for suppressing random (turbulence induced) vibrations of a plate like wing with embedded piezoceramics are investigated. An electromechanically coupled finite element model (that accounts different external circuits) is combined with unsteady aerodynamic models (the doublet-lattice method and Roger’s model) to develop a piezoaeroelastic model of cantilevered plates representing wing-like structures. An atmospheric turbulence model (Von-Karman’s and Dryden’s spectrum) is used to induce random vibrations at different airflow speeds. An active controller and different piezoelectric shunt circuits – passive and hybrid (combining passive circuits and voltage sources – are applied to suppress random vibrations over a range of airflow speeds when a single pair of piezoceramics is modeled on the clamped end of the plate. The behavior of the piezoaeroelastic system is investigated in time and frequency domains. Simulation results demonstrate that the hybrid control approach is more effective than purely passive or active controllers.

Effects of a piezoelectric based nonlinear energy sink on the behavior of an electromechanically coupled beam

Various researchers have investigated the behavior of a linear oscillator weakly coupled to a nonlinear mechanical attachment that has essential stiffness nonlinearity. Under certain conditions, the essentially nonlinear attachment can act as a nonlinear energy sink (NES) and the irreversible transfer of vibration energy from a main structure to the nonlinear attachment is observed. Another characteristic of an essentially nonlinear attachment is the nonexistence of a resonance frequency. Therefore, nonlinear energy sinks have increased robustness against detuning. While mechanical nonlinear attachments are usually linked to a host structure by nonlinear mechanical elements, linear coupling (piezoelectric transduction) is observed in piezoelectric based nonlinear energy sinks and nonlinearity can be achieved through electrical circuit design. This work presents an experimentally validated piezoelectric based nonlinear energy sink. An essentially nonlinear piezoelectric shunt circuit and its practical realization are discussed in detail. The circuit nonlinear behavior and the performance of the piezoelectric nonlinear energy sink to attenuate vibrations of a cantilever over a wide range of frequencies are experimentally validated.

Self-Powered Active Control for an Aeroelastic Plate-Like Wing Using Piezoelectric Material

This paper presents the self-powered active control of elastic and aeroelastic oscillations. A plate-like wing with two piezoelectric layers on the bottom surface and one piezoelectric layer on the top surface is modeled along with an electrical circuit. The direct piezoelectric effect of the bottom layer is used for mechanical to electrical energy conversion. The electrical circuit calculates the control voltage to be applied into the top piezoelectric layer that works as an actuator. The required actuation energy is fully supplied by the harvested energy. The control voltage is obtained from a Linear Quadratic Regulator (LQR) control law. Three cases are investigated. In the first one the harmonic base excitation of the cantilevered wing is considered, the suppression of flutter oscillations is investigated in the second case and the atmospheric turbulence induced vibrations problem is presented in the third case. The performance of the self-powered controller is similar to the performance of a conventional active controller with limited control voltage.© 2014 ASME

Vibration Suppression of a Plate-Like Wing Under Atmospheric Turbulence Using Passive And Hybrid Piezoelectric Circuits

Damping of structural vibrations by passive, active and hybrid piezoelectric networks has received great attention in recent years. This work investigates methods to damp random vibrations induced by atmospheric turbulence of a plate like wing with embedded piezoceramics by means of passive, active and hybrid (passive and active combined) multimodal piezoelectric circuits. The multi-modal piezoelectric circuits are connected to a single pair of piezoceramics. An electromechanically-coupled finite element model based on Kirchhoff plate assumptions is combined with unsteady aerodynamic models (the doubletlattice method and Roger’s approximation) for predicting the wing displacements as well as electrical outputs. The atmospheric turbulence model based on Von-Karman’s spectrum is used to induce random vibrations at different airflow speeds. The behavior of the piezoaeroelastic system is investigated in time and frequency domains. Simulation shows that active and hybrid control can provide approximately the same vibration damping. However, more energy is required for the active case.