Free Vibration Analysis of Sandwich Cylindrical Shells with Functionally Graded Core and Sensor and Actuator Piezoelectric Layers

Abstract

An analytical method for free vibration analysis of a cylindrical FG shell integrated by two thin piezoelectric layers is presented in this paper. The piezoelectric layers on inner and outer surfaces of the core could be considered as sensor and actuator used in controlling the characteristic vibration of the system. One of the innovations of this paper is that the piezoelectric layers considered as functionally graded materials. The First order shear deformation theory is used in order to model the electromechanical system. Nonlinear Equations of motion are derived by considering Von Karman nonlinear strain-displacement relations using Hamilton’s principle. The equations of motion are discretized by Navier method. Numerical simulation after linearization is performed to investigate the effect of different parameters of structure on the characteristic vibration of the system. Results of this study show that natural frequency of system would decrease by increasing FGM index of the core. Also increasing the thickness of core cause increasing the natural frequency of system.