基于薄板理论的密排结构CMUT发射声场研究  

Study on Sound Field Emitted by Close-Packed CMUT Element Based on Thin Plate Vibration Theory

作　　者：沈姝君 何常德[1] 张彦军[1] 高鹏飞[1] 张国军[1] 杨玉华[1] 王任鑫[1] 张文栋[1] SHEN Shujun;HE Changde;ZHANG Yanjun;GAO Pengfei;ZHANG Guojun;YANG Yuhua;WANG Renxin;ZHANG Wendong(State Key Laboratory of Dynamic Testing Technology Co-constructed by Ministry and Province,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学省部共建动态测试技术国家重点实验室,山西太原030051

出　　处：《压电与声光》2023年第1期98-104,111,共8页Piezoelectrics & Acoustooptics

基　　金：国家重大科研仪器研制项目(61927807)。

摘　　要：由微机电系统(MEMS)工艺制作的电容式微机械超声换能器(CMUT),其具有宽频带,易与电子电路集成制作等优势,在医学成像领域具有广阔的应用前景。为了研究一种密排结构CMUT超声换能器的发射声场特征,该文提出了一种简单的物理域相互作用分析方法。基于薄板的振动理论,由CMUT单元的声学辐射原理及特性计算得到CMUT阵元辐射声场的解析解。通过振膜振动分布实验验证了采用薄板振动理论一阶振型方程的正确性。通过仿真和实验研究了CMUT发射单元在不同排布方式和条件下的声场分布、声轴声压和指向性,为CMUT的设计和性能分析提供了理论依据。The capacitive micromachined ultrasonic transducer(CMUT)made by MEMS technology has the advantages of wide frequency band,easy integration with electronic circuits,and broad application prospects in the field of medical imaging.In order to study the characteristics of acoustic field emitted by a close-packed CMUT,a simple physical domain interaction analysis method is proposed in this paper.Based on the vibration theory of thin plate,the analytical solution of the radiation sound field of CMUT element is obtained by the calculation from the acoustic radiation principle and characteristics of CMUT cell.The correctness of the first-order vibration mode equation based on the thin plate vibration theory is verified by the vibration distribution experiment of diaphragm.Through simulation and experiment,the acoustic field distribution,axial sound pressure and directivity of CMUT transmitter units under different arrangement modes and conditions are studied,which provides theoretical basis for the design and performance analysis of CMUT.

关 键 词：电容式微机械超声换能器 薄板振动 声场 声轴声压 指向性 声发射特性 

分 类 号：TB552[理学—物理] TN384[理学—声学]