作者：孙敏, 王月兵, 曹永刚, 郑慧峰, 熊久鹏

作者单位：中国计量大学计量测试工程学院, 浙江 杭州 310018

关键词：多阵元;聚焦换能器;自然聚焦;相控聚焦;声场分布

摘要：

设计一种新型多阵元聚焦换能器，通过对27片自聚焦的圆弧施加延时信号，实现声束的聚焦和偏转，该换能器由27个宽度1.5 mm、曲率半径45 mm、张角60°的弧形阵元线性排列构成，工作频率为350 kHz。用Rayleigh积分对该换能器的声场进行理论推导，并仿真计算自然聚焦和相控聚焦0，10，20 mm状态下的声场分布。实验测量结果表明在-12~12 mm的偏转范围内与仿真基本一致，主瓣声压级降低至-3 dB、-6 dB时，各相控偏转位移对应主瓣宽度与仿真基本吻合，而大于该偏转范围时，主瓣宽度比理论值更大，说明此换能器具有较大的偏转范围与良好的相控聚焦性能，最后讨论由相幅一致性而引入的误差。

Research on focusing characteristics of the arc-array transducer
SUN Min, WANG Yuebing, CAO Yonggang, ZHENG Huifeng, XIONG Jiupeng
College of Metrological Technology and Engineering, China Jiliang University, Hangzhou 310018, China
Abstract: A novel multi-element focusing transducer was designed. The acoustic beam which can focus and deflect was achieved by applying a delay signal to 27 self-focusing arcs. The transducer consists of 27 linear array elements with a width of 1.5 mm, a radius of curvature of 45 mm, and an aperture angle of 60 degrees. The operating frequency is 350 kHz. The field of the transducer was theoretically deduced by using Rayleigh integral, and the field distribution under natural focusing and phase-controlled focus at 0, 10, and 20 mm was simulated and calculated. The experimental measurement results show that the simulation is basically consistent with the experiment within the deflection range of -12 mm to 12 mm. When the pressure of the main lobe is reduced by -3 dB and -6 dB, the main lobe width is basically consistent with the simulation in different phased deflection displacements. However, above this deflection range, the main lobe width is greater than the theoretical value. This shows that this transducer has a larger deflection range and good phase focusing performance. Finally, the errors introduced by the consistency of the phases are discussed.
Keywords: multiple elements;focusing transducers;natural focusing;phase focusing;field distribution
2019, 45(6):101-108  收稿日期: 2018-04-27;收到修改稿日期: 2018-06-05
基金项目: 国家自然科学基金（11474259）
作者简介: 孙敏(1994-),男,浙江宁波市人,硕士研究生,专业方向为仪器仪表工程
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