基于有限元法的局部动力参数识别方法

基于有限元理论，利用谐波平衡法推导出适用于刚度和阻尼参数识别的理论方程，分别按正余弦和复数形式展开求解，并以一典型转子系统为例进行子模型支承刚度与阻尼的识别验算.研究结果表明:两种展开形式均能实现边界参数的识别，且识别结果准确可靠.但由于正、余弦展开求导后形式复杂，不利于完成非线性特征的识别；而复数展开形式能简化计算和推导过程，可较好地完成线性和非线性解的识别，并且识别精度较高.该研究结果为此类系统的设计与振动分析提供了理论参考.

Identification Method of Local Dynamic Parameters Based on FEM

Based on the finite element theory， an theory equation which can be adapted to identify parameters of stiffness and damping was derived by harmonic balance method. The equation was solved by in the form of trigonometric function(sine， cosine)and plural respectively. A typical rotor system case was simulated to check the supporting stiffness and damping of subsystems. The results show that both kinds of forms can identify boundary parameter accurately and reliably. But the forms of sine and cosine expansions are so complicated after derivation that it is unfit for identification of the system nonlinear characteristics. The form of plural expansion can simplify the process of calculation and deduction， and it can well identify both the linear solution and nonlinear solution with higher precision. This study can provide theoretical reference for design and vibration analysis of such systems.