首先介绍了有效质量的概念，然后根据其物理意义推导了有效惯量的计算公式，最后结合有限元技术总结了一种利用长叶栅有效惯量计算轴系扭振频率的方法。该方法既可用于分支系统模型进行扭振模态计算，比传统分支系统扭振分析的精度更高；也可应用于简化轴系有限元模型，在保留精度的前提下，比全尺寸非线性有限元模型消耗更少的时间和资源。

In this paper, the concept of effective mass is introduced firstly, then the formula of effective inertia is deduced according to its physical meaning. At last, combined with finite element technology, a method for calculating the torsional vibration frequency of shafting by using the effective mode inertia of long cascade is summarized.The rule can be used to calculate the torsional vibration mode of the branch system to improve the branch system’s accuracy. It can also be used to the finite element model of the simplified shafting system and consume less time and resources thanfullsize nonlinear finite element model under the premise of preserving precision.

TK288

国家科技重大专项课题项目（2012ZX06002-017-01-04-02）