A FEM-BEM interactive coupling for modeling the piezoelectric health monitoring systems

Abstract

In this research, finite element and boundary element methods are coupled together to model the interaction of a piezoelectric ceramic working as an actuator with an elastic material. Piezoelectric-elastic material's interaction occurs in smart structures. This work is aimed at determining the actuation effects being transferred from the actuators to the host and the resulting overall structural response. To obtain the amount of these actuations, the system of the host structure and an actuator has been modeled by using coupled finite element boundary element method in frequency domain. The host structure, which is assumed as an isotropic elastic solid region is modeled as a half space. The piezoelectric ceramic region is modeled by the 3-D finite element method, while the elastic half space with boundary element method. Finite element model of piezoelectric ceramic and boundary element model of the elastic half space are coupled together at their interface such that the vibrations of the piezo-actuator induce vibrations in the elastic half space. A couple of examples are given to show the induced displacement field around the piezo-actuator on the surface of the elastic medium. The results show that high jump in magnitude of horizontal displacements at the corners of the actuator attached to the structure occurs, which is an indication of high stress concentration, of the shear stress type at the corners. This stress concentration sometimes causes complete debonding of the actuator from the base structure. By using the suggested BEM-FEM coupled model for actuators with different dimensions or material properties much useful information concerning the amount of actuation and load transfer can be obtained. The presented work is a step towards modeling of structural health monitoring systems.

The Influence of Flexure Variation to Vibration-Assisted Micro-Milling Device by Using Finite Element Analysis

“…During machining, the amplitude displacement output from the piezoelectric actuator ranges between 0-10 micrometres and works based on the actuator material properties 24,25) . Several studies show amplitude displacement can be measured using displacement sensor 26,27) or predicted using Finite Element Analysis (FEA) [28][29][30][31] . The measurement method is more accurate than the prediction ones, but this method requires high investment in the micro displacement sensor and the ultrasonic-assisted micro-milling device prototype.…”

Analytical and numerical modelling of deflection of circular three-layer piezoelectric transducer

“…In practice, most piezoelectric transducers usually have a layered structure, which causes some difficulties in determining their characteristics. For actual transducers, the dependence between deflection and the applied load can be determined through numerical [9][10][11][12], analytical-numerical [12][13][14][15] or analytical methods. Currently, numerical methods are very popular.…”