Behavior of a 3-layered thick piezoelectric actuator using a 2-D coupled electromechanical model

A new two dimensional coupled electromechanical model for a three-layered thick, laminated actuator with piezoelectric and isotropic lamina is developed here. The model adopted the first order shear deformation theory for the central, thick elastic core (i.e., considered as Timoshenko beam) which is sandwiched with piezoelectric laminae modeled by linear piezoelectric theory. Unlike the common approach of using the thin beam theory, the thick piezoelectric laminae are modeled as two-dimensional piezoelectric layers. The response is induced through the application of external electric voltage across the piezoelectric laminae. The Ritz method is adopted to model the displacement and the potential fields of the actuator and the governing equations are finally derived via the variational energy principle. In this study, the actuator is simulated as a cantilever and the behavior under external voltage is investigated. Numerical examples of the 3-layered piezoelectric laminated beam are also presented. It is verified that the numerical results are in good comparison with finite element solutions.