圆柱形切向极化复合压电超声换能器

The cylindrical composite piezoelectric ceramic transducer polarized in tangential direction

设计了一种圆柱形切向极化复合压电超声换能器,这种复合换能器由金属薄壁圆管和切向极化压电陶瓷圆管组成.根据金属薄壁圆管径向振动的等效电路以及切向极化压电陶瓷圆管径向振动的等效电路,推导了该复合换能器的等效电路图,根据等效电路给出了换能器的谐振频率和反谐振频率的计算公式.并应用有限元数值分析方法,建立复合换能器的有限元模型,分析了复合换能器的振动模态和最优结构参数.并根据数值分析结果,设计和制作了圆柱形切向极化复合压电超声换能器,运用阻抗分析仪对换能器的阻抗特性进行了实验测试.分别由三种方法得到了圆柱形切向极化复合压电超声换能器的导纳与频率关系曲线,谐振频率及反谐振频率.经过比较三种方法的结果,等效电路方法得出的谐振频率和反谐振频率与有限元仿真结果和实验结果一致.

In this paper,The cylindrical composite piezoelectric ceramic transducer polarized in tangential direction is presented and studied.The cylindrical composite piezoelectric ceramic transducer consists of an inner tangential polarized piezoelectric ceramic thin-walled circular tube and an outer metal thin-walled cylindrical shell which are composed in the radial direction.The radial vibrations of a metal thin-walled cylindrical shell and a piezoelectric ceramic thin-walled circular tube were analyzed.And their radial electro-mechanical equivalent circuits were obtained.Based on the equivalent circuits and the radial boundary conditions,the composite electro-mechanical equivalent circuit of the cylindrical composite piezoelectric ceramic transducer polarized in tangential direction was deduced,and the resonance and anti-resonance frequency equations of the transducer were derived.Through Finite Element Method（FEM）,Finite element model of composite transducer was established,The vibration model and the optimum configuration parameters of the transducer were analyzed.Then on the basis of the Finite Element Methodnbsp;calculated results,the prototype transducer polarized in tangential direction was designed and manufactured,and the impedance characteristics was measured by the Impedance Analyzer.The admittance and frequency curve,the resonance frequency and the anti-resonance frequency of the cylindrical composite piezoelectric ceramic transducer polarized in tangential direction were obtained by each methods.By contrast,the resonance frequencies and the anti-resonance frequencies from the experimental results are in agreement with those from the frequency equations and Finite Element Method calculated results.