基于1-3压电复合材料的透镜式聚焦换能器设计

Design of a Lens-focused Transducer Based on 1-3 Piezoelectric Composites

为了抑制压电陶瓷透镜式聚焦换能器振动的多模耦合现象,提高换能器电声转换效率,采用1-3压电复合材料,设计了一种新型的透镜式聚焦换能器;首先计算并仿真了1-3压电复合材料的厚度谐振频率ft和厚度机电耦合系数kt,理论和仿真结果分别相差2.947%和0.933%;接着对换能器做振动分析,结果表明,在换能器谐振频率ft处,声透镜中心径向振幅仅为厚度振幅的7.9%,径向振动得到有效抑制,这有助于提高换能器电声转换效率。

To suppress the multi-mode coupling effect and improve the electro-acoustic conversion efficiency of a lens-focused transducer made of the piezoelectric ceramic material,a novel lens-focused transducer using 1-3 piezoelectric composites is designed in this work.First,the thickness resonant frequency ft and thickness electro-mechanical coupling coefficient kt of the 1-3 piezoelectric composites were calculated and simulated,the difference between the theoretical value and the simulation value for ft and kt are 2.947% and 0.933% respectively.Next,the vibration condition of the transducer was analyzed.At the resonant frequency ft of the transducer,the displacement amplitude at radial direction of the acoustic lens center is only 7.9% of the thickness direction,which shows that the radial vibration has been suppressed effectively,and thus the electro-acoustic conversion efficiency of transducer has been improved.This study could be used as reference in the development work on focused transducers.