利用结构动态特性修改及灵敏度分析减小机体振动

Reducing Engine Block Vibration With the Methods of Structure Dynamic Characteristic Modification and Sensitivity Analysis

利用机体试验模态分析结果建立了用于机体结构动态特性分析的有限元模型，分析了机体振动模态及结构刚度的分布变化规律，将矩阵摄动理论及灵敏度分析方法应用于机体动态特性的修改之中，确定影响机体各阶动态特性的结构参数及其位置，优化结构动态特性，使得针对某一频率的减振降噪成为可能。文中对机体结构动态设计的几个主要步骤进行了探讨。

In this paper, a finite element model to analyze block structuredynamic characteristic is given by the result of test modal analysis. Block vibration modality and the distribution of the structure stiffness are analyzed. Thetheory of perturbation and sensitivity analysis are used to modify the block dynamic characteristics. Structure parameters that affect block dynamic characteristics and their locations are found out. It is possible to reduce vibration andnoise responsed to a certain frequency through optimizing the structure dynamiccharacteristic. Several main steps of block dynamic design are discussed.