厚度振动换能器降耦合结构优化与工程应用  

Optimization and engineering application of coupling weakening structure in thickness vibration transducer

作　　者：赵慧 李海森[1] 王艳[2] 卞加聪[2] 李科 ZHAO Hui;LI Haisen;WANG Yan;BIAN Jiacong;LI Ke(College of Underwater Acoustic Engineering,Harbin Engineering University,Harbin 150001,China;Shanghai Marine Electronic Equipment Research Institute,Shanghai 201108,China)

机构地区：[1]哈尔滨工程大学水声工程学院,哈尔滨150001 [2]上海船舶电子设备研究所,上海201108

出　　处：《振动与冲击》2021年第17期124-130,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(41906175)。

摘　　要：厚度振动是高频换能器的常用振动模态。对压电圆片而言,横向方向的耦合总是存在的,不存在理想的厚度振动模态。若压电圆片的尺寸比例合适,横向耦合较弱,若尺寸比例不合适,横向耦合会很强。耦合会使振子表面振动位移反相,频响曲线出现多个难以区分的谐振峰,对换能器的发送电压响应、指向性等产生负面影响,对某军用型号工程中利用该振动模态工作的换能器的生产质量有较大影响。通过对压电振子的振动模态、耦合振动频率等理论和仿真计算,开展频率优化研究,降耦合对换能器的影响分析以及试验验证,仿真分析和试验结果表明:中心孔对圆片高频换能器模态振动具有明显的降耦合作用,可提高圆片换能器的发射能力,改善指向性特性,解决了该类换能器生产质量不高、成品率低等问题。Thickness vibration is a commonly used vibration mode of high frequency transducers.For a piezoelectric disc,coupling in lateral direction always exists,and there is no ideal thickness vibration mode;if its size scale is appropriate,lateral coupling is weak;if its size scale is not appropriate,lateral coupling is strong.Coupling can make a vibrator’s surface vibration displacement be inverse phase and its frequency response curve have multiple resonance peaks being difficult to distinguish,which has a negative impact on transmitting voltage response and directivity of the transducer,and has a larger impact on production quality of transducers using thickness vibration mode in a certain military project.Here,through theoretical study and simulation calculation of vibration modes and coupling vibration frequencies of a piezoelectric vibrator,the frequency optimization,the influence analysis of coupling weakening action on transducer and the test verification were performed.The simulation analysis and test results showed that the central hole has the obvious action of coupling weakening on modal vibrations of a circular disc high frequency transducer;it can improve the transmitting ability and directivity of the circular disc transducer to solve problems of low production quality and low yield of this kind of transducers.

关 键 词：厚度振动 耦合 径向振动 发送电压响应 指向性 

分 类 号：TB565.1[交通运输工程—水声工程]