螺旋叉指电极式压电圆片换能器的有限元分析与实验比较

摘要

螺旋叉指电极式压电圆片换能器可以产生面内扭转运动，具有结构简单、加工方便、性能可靠等优点，可用于超声马达、光学扫描、黏度测量等领域；但表面螺旋叉指电极间陶瓷材料的极化方向变化复杂，给换能器的机电耦合分析和优化设计带来极大的难度。利用坐标变换思想与有限元方法，将压电圆片分割成若干子体，通过极化电场分析确定子体局部坐标系以定义材料参数，从而实现复杂极化情况下压电换能器的耦合仿真分析。利用 ANSYS 有限元软件，优化仿真分析过程，研究了该压电圆片换能器的静态扭转位移径向分布特性和动态导纳频率响应特性，并与实验结果相比较，证实了该方法的可行性和有效性。%A piezoelectric disk with spiral interdigitated electrodes (SIEDs)can produce in-plane torsion with advantages of simple structure,convenient manufacture,and reliable performance,it can be applied in ultrasonic motors, optical scanners,viscometers,and many others.However,because of the complex variation of polarizing direction of piezoceramic material between surfaces SIEDs,great difficulties are brought for electromechanical coupling analysis and optimal design of the transducer.Here,utilizing the idea of coordinate transformation with the aid of the finite element method,the piezoelectric disk was divided into a number of sub-volumes.The material parameters were defined in the local coordinate systems determined with the analysis of polarized electric field.Thus,the coupling simulations of the piezoelectric transducer were achieved under the complex polarization conditions.The simulation processes were optimized with the finite element software ANSYS,the radial distribution of static torsional displacement and the frequency response features of dynamic admittance of the transducer were investigated.Comparing the simulation results with the test ones, the feasibility and effectiveness of the proposed method were validated.