基于有限元法的液体媒质超声波电机内部声流场分析及饱和流速研究  

FEM Analyses on Acoustic Streaming Field and Saturated Flow Velocity of Ultrasonic Motor Driving Fluid Directly

作　　者：夏长亮[1] 俞卫[1] 李斌[1] 史婷娜[1] 

机构地区：[1]天津大学电气与自动化工程学院,天津市南开区300072

出　　处：《中国电机工程学报》2006年第18期143-147,共5页Proceedings of the CSEE

基　　金：国家自然科学基金项目(50207006);高等学校博士学科点专项科研基金(20040056021);天津市自然科学基金项目(05YFJMJC11300)。~~

摘　　要：与一般超声波电机依靠定、转子之间的摩擦来传递能量不同,非接触型超声波电机的定、转子并不直接接触。该文介绍了液体媒质超声波电机的基本结构及运行机理,阐述了电机运行过程中能量传递的基本过程,揭示了液体中的雷诺应力是电机声流场的驱动力。文章基于Kuznetsov非线性波动方程有限元方法,对液体媒质超声波电机内部声流场进行数值仿真。由声场中的液体微粒振动速度计算声流场驱动力,随后在流体域内用有限元法计算液体的流速。仿真中分别考虑了声场衰减、定子驱动电压及声场非线性对声流场驱动力与液体流速的影响。在数值分析的基础上,对电机运行过程中存在的饱和流速问题进行了进一步的分析。实验结果验证了有限元分析的有效性。Compared with conventional ultrasonic motors using friction coupling, non-contact type ones, in which the stator and the rotor do not contact directly, is a new research direction in the field of ultrasonic motors. A new ultrasonic motor driving fluid directly is introduced in this paper. Fundamental construction and operation mechanism are both covered, as well as the course of energy transferring. It is revealed that the main driving force of the acoustic streaming field inside the motor is stemming from the Reynolds stress. Then a new finite element method （FEM） based on the nonlinear wave equation derived by Kuznetsov is applied to simulate the acoustic streaming field. The driving force of acoustic streaming field is calculated from the acoustic fluctuating velocity, which is the result of nonlinear analysis of the acoustic field. Such force is then transferred to the fluid dynamic finite element model, and the velocity of the fluid streaming is obtained. The influence of acoustic damping, acoustic nonlinearity and the exciting voltage of the stator are considered. Based on the numerical analysis, the saturated flow velocity is discussed further. The experimental results verify the validity of FEM scheme.

关 键 词：超声波电机 非接触 有限元 液体 雷诺应力 声流场 

分 类 号：TM359[电气工程—电机]