Modeling and designing of a phased array comprising piezoelectric stack transducer for ultrasonic Lamb wave-based damage detection

With rapid damage diagnosis, long detection range, and high damage sensitivity, the ultrasonic Lamb wave-based technique has been regarded as an effective tool to detect damage in large engineering structures. In recent years, the phased array detection method has been extensively investigated, while the development of a reliable phased array transducer for addressing the wave energy attenuation problem is still in the exploration phase. In this article, a novel type of piezoelectric stack phased array transducer is designed and proposed for the first time, capable of easily providing high guided wave excitation energy for damage detection in large-scale structures. For detection frequency selection, a semianalytical finite-element method is developed for different excitation and sensing model with d-31- and d-33-type piezoelectric transducers. At the selected frequency, a detailed parametric study of the piezoelectric transducer has been conducted for high-energy excitation, validated by the results of a comparative experiment. Finally, utilizing a phased array beamforming approach, the designed piezoelectric stack phased array transducer proves highly effective in identifying damage in plate-like structures. The piezoelectric stack phased array transducer, comprising one piezoelectric stack transducer and nine piezoelectric sensors, possesses excellent excitation and sensing capabilities for damage detection, as confirmed by experimental results. This work introduces a novel approach for effectively detecting damage in large-scale engineering structures.