Modeling and analysis of Lamb wave propagation in a beam under lead zirconate titanate actuation and sensing

Abstract

Lead zirconate titanate actuators and sensors have been the widely used in Lamb wave–based damage detection applications. The excitation frequency, waveform, and wave propagation characteristics should be comprehensively considered to effectively conduct diagnosis of incipient forms of damage. In this article, we investigate Lamb wave propagation in a beam under lead zirconate titanate actuation/sensing, in which the lead zirconate titanate effects are included. First, mathematical models are developed to account for both unimorph (i.e. sensor mode) and bimorph (i.e. actuator mode) configurations. The Timoshenko beam theory is adopted for both base beam and lead zirconate titanate layers to accommodate high-frequency responses. Second, the fully coupled electromechanical governing equations are determined and solved in an analytical form to formulate the spectral finite element model. Finally, parametric studies are carried out to determine the optimal actuation frequency, sensor size, actuator, and sensor placement. Our spectral finite element model predictions are validated by the experimental data and results in the literature. The application of spectral finite element model in the Lamb wave–based damage detection is demonstrated as well. In summary, the newly developed spectral finite element model provides an analytical framework in which to predict Lamb wave propagation under lead zirconate titanate actuation and sensing, as well as to develop new interrogation schemes.