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第 38 卷 第 5 期                                                                       Vol. 38, No. 5
             2019 年 9 月                          Journal of Applied Acoustics                 September, 2019

             ⋄ 研究报告 ⋄

                             多层介质中超声相控阵声场仿真                                               ∗


                                           郭忠存     1,2   阎守国     1†   张碧星     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    由于良好的声束偏转与聚焦特性,超声相控阵已经广泛应用于多层固体介质的缺陷检测。当超声束经
                过多层介质时,由于反射、透射以及模式转换的存在,多种声束存在于这种结构中,使得声场分析变得复杂。为
                了提高多层介质检测的准确性,有必要对超声声场的分布规律进行深入地了解。该文结合高斯声束等效点源
                模型以及射线追踪法,给出了相控阵声源在多层固体介质中激发声场的仿真方法,并且模拟计算了一维线型
                相控阵在楔块 -铝 -黄铜 -钢四层固体介质中的辐射声场。通过对不同延时法则的计算,实现了声波在这种复杂
                介质中的偏转与聚焦,进而研究了不同焦点处聚焦声场的分布。结果表明:相控阵方法能使聚焦点处的声场幅
                值增大,能量集中,提高了检测分辨率;不同聚焦点处声场聚焦效果不同,实际检测时应根据检测区域结构及
                位置特点,合理放置相控阵换能器。与瑞利积分法的比较表明,该文的仿真方法适用于多层介质相控阵声场的
                计算。
                关键词     超声相控阵,多层介质,声场仿真
                中图法分类号: O426.9          文献标识码: A          文章编号: 1000-310X(2019)05-0788-07
                DOI: 10.11684/j.issn.1000-310X.2019.05.005

                      Simulation of acoustic fields generated by ultrasonic phased array

                                               in multilayered medium

                                    GUO Zhongcun  1,2  YAN Shouguo  1  ZHANG Bixing  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  With the advantage of beam steering and focusing, ultrasonic phased array has been applied to
                 the inspection of multilayered medium. When the ultrasonic beam is propagating through such medium, due
                 to the reflection, refraction and mode conversion, several different beams exist, which may bring interferences
                 to analysis of acoustic fields. To improve detection efficiency in multilayered medium, it is necessary to have an
                 in-depth knowledge of the characteristics of ultrasonic fields. A systematic method combining Gaussian beam
                 equivalent point source (GBEPS) model and ray tracing technique is given and the acoustic field generated by
                 ultrasonic phased array in wedge-aluminum-brass-steel four layered medium is calculated using such method.
                 Through the calculation of time delay laws, beam steering and focusing are realized and the focused fields with
                 different focal points are studied. Simulation result shows that, using phased array transducer, the amplitude
                 of acoustic field at focal point can be increased, the energy can be focused, and the detection resolution can
                 be improved. The focus effect is different at each focal point, therefore, the phased array transducer should
                 be placed reasonably according to the structure and position of detection zones during actual inspection. In
                 addition, compared with Rayleigh integral method, the method proposed here is capable of calculating acoustic
                 fields generated by ultrasonic phased array in multilayered medium.
                 Key words Ultrasonic phased array, Multilayered medium, Simulation of acoustic fields


             2018-10-17 收稿; 2018-10-29 定稿
             国家自然科学基金项目 (11474308, 11574343, 11774377)
             ∗
             作者简介: 郭忠存 (1991- ), 男, 山东济宁人, 博士研究生, 研究方向: 超声传播与成像。
             † 通讯作者 E-mail: yanshouguo@mail.ioa.ac.cn
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