Study the Effect of Acoustic Load on the Performance for Sandwiched Piezoelectric Ultrasonic Transducers

摘要

Sandwiched piezoelectric ultrasonic transducers (SPUTs) are widely used in ultrasonic detection applications especially in structural health monitoring (SHM). To improve detection efficiency, the selection of excitation frequency for SPUTs is extremely significant. Based on the PSpice lossy model of SPUT, the effect of acoustic load on the electromechanical characteristics of SPUTs was investigated in time and frequency domains in this paper. It is shown that the primary resonance frequencies are shifted and the SPUT generate multiple resonant modes when different length aluminum rods are connected. In addition, the effective electromechanical coupling coefficient and the vibration velocity on the front surface of the aluminum rod are decreased under acoustic load. It can be concluded that the simulated analyzed results are in good agreement with the measured ones.