Page 77 - 《应用声学》2020年第4期
P. 77

第 39 卷 第 4 期                                                                       Vol. 39, No. 4
             2020 年 7 月                          Journal of Applied Acoustics                      July, 2020

             ⋄ 研究报告 ⋄



              利用激光多普勒测振仪的空气耦合超声声场测量                                                                       ∗




                                    吴 樵     1,2  周雨轩      1,2  廉国选      1  王小民      1†


                                    (1 中国科学院声学研究所       声场声信息国家重点实验室        北京   100190)
                                                (2 中国科学院大学      北京  100049)

                摘要：针对空气耦合超声信号微弱、难以直接测量的问题，进行了空气耦合超声声场测量的实验研究。使用
                激光多普勒测振仪测量由声波引起的激光路径上的介质折射率变化，进而得到空气和固体材料内部的时域
                瞬态声压。通过直接测量空耦换能器的辐射声功率，给出对单个空耦换能器灵敏度的直接评价方法。用空耦
                换能器激励 K9 玻璃板的漏兰姆波，观测到空气中的直达波和反射波、固体板内和空气中的漏兰姆波，实现了
                空气和固体中微弱声波的非侵入式实验测量，为空耦换能器的特性评估和空耦检测系统的声场测量提供了
                实验方法。
                关键词：激光多普勒测振仪；空耦换能器；声压测量
                中图法分类号: TB551           文献标识码: A          文章编号: 1000-310X(2020)04-0563-07
                DOI: 10.11684/j.issn.1000-310X.2020.04.010




                           Air-coupled ultrasound acoustic field measurements using
                                             laser Doppler vibrometers


                             WU Qiao 1,2  ZHOU Yuxuan  1,2  LIAN Guoxuan  1  WANG Xiaomin   1


                  (1 State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China)
                                   (2 University of Chinese Academy of Sciences, Beijing 100049, China)

                 Abstract: An experimental research of acoustic field measurement is carried out aiming at the weakness air-
                 coupled signal. Using the laser Doppler vibrometer, the variation of refractive index of the media along the
                 laser path can be measured, which is caused by acoustic waves. The temporal acoustic pressure signals in air
                 or solid media can thus be obtained. By measuring the radiated acoustic power, a direct assessment method of
                 the sensitivity of single air-coupled transducer is given. Leaky Lamb wave of K9 glass plate in the air excited
                 by air-couple transducers is given. The temporal acoustic pressure signals of the direct and reflective waves
                 in the air, the leaky Lamb wave both in solid and air are observed. The experimental measurement of low
                 amplitude acoustic waves in air or solid media is achieved, providing a direct procedure for the characterization
                 and assessment of air-coupled transducers and the measurement of the acoustic field of air-coupled testing
                 systems.
                 Keywords: : Laser Doppler vibrometers; Air-coupled transducers; Acoustic pressure measurement




             2019-09-20 收稿; 2019-11-28 定稿
             国家自然科学基金项目 (11504407)
             ∗
             作者简介: 吴樵 (1990– ), 男, 湖北武汉人, 博士研究生, 研究方向: 超声检测与换能器。
             † 通信作者 E-mail: wangxiaomin@mail.ioa.ac.cn
   72   73   74   75   76   77   78   79   80   81   82