失谐叶盘结构振动模态局部化研究

针对失谐叶盘结构振动特性和模态局部化特性,分别利用有限元法和子结构模态综合法进行分析。对具有12个叶片模拟叶盘结构的振动特性和振动模态局部化特性进行研究,包括失谐形式对模态局部化的影响和模态密度对失谐敏感性的影响,并利用应变能和模态局部化因子的概念对模态局部化现象进行定量描述。研究表明:子结构模态综合法能满足叶盘结构振动模态特性的计算精度要求,并能节省大量的计算时间;失谐形式和模态密度对模态局部化程度有显著影响。

Investigation of Vibration Mode Localization of Mistuned Bladed-disk Assemblies

The vibration characteristics and the localization characteristics of a mistuned bladed-disk were analyzed by FEM and substructure component mode synthesis. The vibration characteristics and the localization characteristics of the analog bladed-disk model with twelve blades were investigated, including the effect of mistuning form on vibration localization and the effect of mode density on mistuning sensitivity of a mistuned bladed-disk. The phenomenon of vibration localization was quantitatively described with the concepts of strain energy and localization factor. The results show that the substructure component mode synthesis not only satisfies the precision but also saves computing time. The mistuning form and mode density have significant influence on vibration localization.