<title>Finite element model for active constrained layer damping</title>

Abstract

Constrained layer damping has been used for many years to increase the damping in engineering structures. Active damping using smart materials has been investigated a great deal recently. Several researchers have suggested the concept of using viscoelastic materials with piezoceramics as the constraining layer. Since the piezoceramics are active materials, this concept can be referred to as active constrained layer damping. The paper presents a finite element model for a sandwich beam consisting of a host layer, a viscoelastic layer, and a piezoelectric layer. Lesieutre's method (Augmenting Thermodynamic Fields) for modeling damping was modified and applied to active constrained layer damping. The effects of the thickness and stiffness of the viscoelastic layer are studied. Experimental transfer functions for various configurations are presented. Active damping and passive damping are individually of interest, however, here we propose to combine these two types of damping to produce an active constrained layer system with the best of both technologies.