【作者】 刘占辉； 刘伟； 高维成； 程翔；

【Author】 LIU Zhan-hui, LIU Wei, * GAO Wei-cheng , CHENG Xiang (Department of Astronautic Science and Mechanics, Harbin Institute of Technology, Harbin, 150001 China)

【机构】 哈尔滨工业大学航天科学与力学系；

【摘要】 失谐循环周期结构的模态局部化现象是近几十年研究的一个热点。本文对单层肋环形球面网壳的模态局部化发生的可能性进行了研究。采用矩阵摄动法分析了模态局部化的发生机理;用数值仿真求得单层球面网壳模型的固有频率和振型,分别绘制了随机失谐和谐波失谐情况下谐调和失谐结构的肋端振型位移值对比图,并用幅值放大系数评估了模态局部化的程度。结果表明在文中引入的结构刚度随机失谐和谐波失谐的情况下单层肋环形球面网壳的某些振型中会发生模态局部化现象,初步分析认为幅值放大系数Ri>5时会有较明显的模态局部化现象发生。进一步深入研究模态局部化现象对基于振动参数的结构损伤识别具有重要的理论意义和工程实际应用价值。更多还原

【Abstract】 Mode localization phenomenon of mistuned cyclically periodic structure has been a focus for concern during the last few decades. In this study, we investigate the possibility of mode localization occurrence in a single-layer reticulated dome model. The mechanism of mode localization was explained by matrix perturbation. The natural frequencies and mode shapes were numerically computed based on a single-layer reticulated dome model. The comparison diagrams of the displacement of the rib end between tuned and mistuned structure are drawn for the case of random mistuning and harmonic mistuning, and then the severity of mode localization was appraised with amplitude increase coefficient. The results demonstrate that in the case of random stiffness mistuning and harmonic stiffness mistuning the mode localization occurred in some order mode of the single-layer reticulated dome. Through primary analysis, we tentatively put forward that a mode can be considered as localized when R i >5. The further research of mode localization has important theoretical significance and engineering practical value for damage identification using modal data.更多还原