| 1. | A fem software as an important tool , work has been done as follows : the method using fem to design anomalous structure of transducers was adopted ; the vibration modes of the elastic pipe , ultrasonic transducers and system has been analyzed in piezoelectric coupled field . resonant frequencies of the transducers have been matched quite well with resonant frequencies of pipe , which can make it easy and accurate to design a transducer . the values of equivalent dynamic capacitors and dynamic inductances of ahead nine orders have been gotten derived by fem method , and fem equivalent circuit of the transducers has been built 以ansys有限元软件为主要分析工具完成了设计工作;在经典换能器设计理论和前人经验的基础上,对不规则形状的换能器采用了有限元的方法设计;在耦合场中分析了换能器、导管及整体装置的振动情况,使换能器的谐振频率与导管的谐振频率达到了较好的匹配,使设计变得更加容易和准确;利用有限元方法建立了振子的等效电路模型,求出了其前6阶模态的等效动态电容电感值,为阻抗匹配和驱动电路的设计提供了依据。 |