Abstract:

The objective of this research is to control the acoustic radiation of thin plates with hybrid active--passive actuating mechanisms. The hybrid mechanism consists of a piezoelectric actuator and viscoelastic and piezoelastic active constrained layers in a sandwich configuration, with the viscoelastic core layer in between the piezoelastic components. The actuator end of the hybrid mechanism is attached to a host structure. The main purpose of the proposed hybrid mechanism is to enhance the damping characteristics of the system while maintaining sufficient control authority. The damping characteristics of the hybrid mechanism is maximized by applying opposite voltages to the actuator and the active constrained layers, thus inducing a significant increase in shear strain within the viscoelastic layer. The general goal of this study is to evaluate the performance of the hybrid mechanism with some of the previously published actuating systems. Initial comparison results indicate that the proposed hybrid active--passive sandwich mechanism is more efficient than the actuating devices in comparison.