压电单晶双激励宽带纵向换能器

Piezoelectric single-crystal dual-excited broadband longitudinal transducer

为了提高纵向换能器发射响应和工作带宽,本文以压电单晶PMNT做为有源驱动材料,采用双晶堆不同尺寸反相激励的方式,同时激发出一阶、二阶纵振模态,从而提高纵向换能器发射响应,拓宽工作频带。通过四端网络法简化换能器的等效电路并计算其发射性能,利用ANSYS软件对模型进行优化设计并制作了试验样机,最终测试数据显示在工作频带27~65 k Hz,最大发射电压响应值不低于150 d B,带内起伏小于12 d B。研究结果表明:理论计算、有限元仿真计算与实测结果基本吻合,利用双晶堆反相激励的方式可实现纵向换能器较宽频带工作。

In order to improve the transmitting response and operational bandwidth of longitudinal transducer,in this paper,the piezoelectric single-crystal(1-x)Pb(Mg 1/3 Nb 2/3)O 3-xPbTiO 3(PMNT)was used as the active driving material,and by means of bicrystal stack different-size inverse-phase excitation to simultaneously motivate the first-order and second-order longitudinal vibration mode,so as to increase the transmitting response of longitudinal transducer and widen the working frequency band.Four-terminal network method was used to simplify the equivalent circuit of a transducer and calculate its transmitting performances,ANSYS software was used to carry out an optimized design for the model and a sample machine used for test was made,the final testing data was displayed within the working frequency band of 27~65 kHz that the response value of the maximum transmitting voltage was not less than 150 dB and the fluctuation scope inside the band was less than 12 dB.The research results show that the FE simulation calculation results and the actually measured results basically coincide and the bicrystal stack inverse-phase excitation means can be used to realize the operation of longitudinal transducer at a wide frequency band.