具有弹性耦合结构振动系统的自由界面模态综合法

FREE-INFERFACE MODE SYNFHESIS METHOD FORVIBRATION SYSTEM OF CONTAINS STIFFNESS COUPLING COMPONENT

本文给出了以弹性连结件为耦合件的振动系统自由界面模态综合技术,把弹性连结件定义为“软子结构”单独处理,其余部件自然划分为若干子结构。利用有限单元法获取各子结构自由界面模态信息,用子结构的截断主模态及其高阶剩余柔度修正项作为结构 RayLeigh-Ritz 分析的假设模态,从而大幅度压缩了结构分析自由度。实例计算表明,该方法具有良好的综合精度,是分析具有弹性耦合结构振动问题的有效方法。

In this paper,a free-interface mode synthesis method for vibration system of contains stiffness coupling component is described.The complete structure system is assumed to be com- posed of a group of components that are interconnected.Among them stiffness coupling com- ponent is defined as“soft substructure”,the others are divided into many substructure by natu- ral.The vibration mode for each component are determined separately by finite element method under the condition of free-interface.The lower-frequency normal modes are kept and the higher-frequency normal modes are neglected by using a frequency truncation criterion.The “residual flesibility”of these neglected modas is considered.Thus,the assumed modes of the whole structure of Rayleigh-Ritz synthesis are formed.Numerical results show that this method yields better synthesis accuracy,it is effective method for analysis a vibration problem of con- tains stiffmess coupling substructure system.