Vibration of Two-Dimensional Functionally Graded Beam with Dynamic Flexoelectric Effect

In this manuscript, a functionally graded beam model considering both flexoelectric and dynamic flexoelectric effects was established. Based on the modified strain gradient theory, the governing equation was reformulated, which included the effects of the dynamic flexoelectric coefficient and the material length scale parameters. Using the electrical open circuit condition, a analytical solutions of the lateral displacement and axial displacement under static bending were obtained. In order to further analyze the influence of dynamic flexoelectric effect on the natural frequency of free vibration, the frequency equation was obtained from Navier method. Numerical results show that the electric potential, polarization, and energy efficiency of functionally graded beam can be controlled by adjusting the gradient index and material length scale parameters. In addition, the simulation results also show that the dynamic flexoelectric effect coefficient has a more significant effect on the natural frequency at small span ratios. This work can provide helpful guidance for designing energy harvesting devices in functionally graded materials.