Theoretical and Experimental Investigation of Ultrasonic Focusing with Annular Phased Array

The focused acoustic field generated by an annular array interface are investigated theoretically and experimentally. transducer and its reflection field on a solid-liquid Theoretically, the concise analytic expressions about the radiation and reflection acoustic fields of the annular phased array are obtained by the ray approach method （saddle-point method）. In experiment, an annular transducer with 8 equal-area elements is designed and fabricated, and a series of experiments about the radiation acoustic field and its reflection on the liquid-solid interface are carried out. The experimental characteristics of the transducer are in good agreement with the numerical ones. It shows the correctness of the theoretical result and the feasibility of dynamic focusing of the experiment system. With the maximum amplitude and its emergence time of the reflection wave, we can acquire the information and the imaging of the reflection interface by the annular phased array dynamic focusing.     

环形相控阵换能器辐射和反射声场

研究了超声环形相控阵辐射声场和反射声场的基本特性。理论上详细分析了环形相控阵的阵元数目、环形阵半径、阵元间距、中心频率、焦点位置等因素对辐射声场的影响。实验上设计并制作了具有8个环的等面积环形相控阵列并进行了实验测量。通过理论和实验分析,研究了环形相控阵的辐射声场及在液固界面上的反射声场特性,取得了理论和实验相吻合的结果。