In the study, interaction between piezoelectric membrane and vortex hydrodynamics of flow behind a bluff body is studied numerically, aiming to optimize the electric power output of piezoelectric membrane by altering thickness of membrane. A two-dimensional Fluid-Structure Interaction Model that simulates the motion and potential difference of piezoelectric membrane under vortex shedding behind a bluff body is constructed by using the computational fluid dynamics (CFD) software - COMSOL Multiphysics. Models under various parameters and conditions concerning different factors such as length of membrane, thickness of membrane and flow speed on vibration of membrane are investigated. Simulations based on laminar flow regime are developed along with Arbitrary Lagrangian-Eulerian (ALE) method. © 2013 AIP Publishing LLC.