Study on the flexible Rayleigh waves comb transducer with non-equidistant interval based on PZT

Abstract

Abstract. In order to detect the defects of inner and outer surfaces of thick-walled pipes, a Rayleigh waves flexible transducer with non-equal interval comb is designed. Firstly, an optimization design method based on the concept of mutual admittance is proposed, and the amplitude frequency characteristics of Rayleigh waves transducer with equal interval comb are optimized. The influence of the key parameters such as the array element interval, the width of the array element and the number of elements on the waveform and amplitude of the received signal are analyzed by using the finite element method. Based on the analysis of the mutual admittance principle and time frequency analysis, it is determined that the optimal element interval is equal to λ R , the element width is λ R /2, and the elements number is 5. Finally, based on the conclusion of equal interval transducer, the non-equal interval comb transducer is designed to obtain a good Rayleigh wave signal, which provided a good foundation for the practical manufacture and experiment of the transducer.