带集中质量块薄板的移频数值仿真  

Numerical Simulation on Frequency Shift of Thin Plate with Lumped Mass Block

作　　者：向建华[1] 廖日东[1] 蒲大宇[1] 

机构地区：[1]北京理工大学机械与车辆学院,北京100081

出　　处：《西安交通大学学报》2010年第11期82-86,共5页Journal of Xi'an Jiaotong University

基　　金：国家重点基础研究发展规划资助项目(1030021210710)

摘　　要：通过对带有附加质量块薄板的理论分析和频率计算,从中获取了影响薄板系统动态特性的质量块主要参数,再运用有限元方法系统地分析了质量块的质量、位置、数量、所处介质和分布面积对薄板频率的影响规律.数值仿真结果表明:通过添加质量块来实现结构移频,应尽量采用质量为结构总质量10%以下的集中质量块,并放置于振型波峰处,以获得最大的频率改变量;沉浸于重质流体的薄板需要更大的附加质量,才能获得与轻质流体相同的频率改变量;对于高阶模态,应尽可能多地在振型峰值上布置质量块并呈对称分布.在此基础上开展的薄板移频技术的应用研究,可为实际薄板结构修改时调整固有频率以避开工作频率、减小振动提供指导.The theoretical analysis and frequency calculation of a thin plate with additional mass blocks were performed to achieve the main parameters of mass blocks that affect the dynamic characteristics of the thin plate. The influence of mass block parameters such as mass value, position, quantity, media, and distribution area on the frequency of the thin plate was discussed with the finite element method. The numerical simulation results show that, when the structural fre- quency shift is realized by adding mass blocks, it is necessary to lay the lumped mass blocks whose mass value is less than 10~ of the total structure mass at the wave peak of the structural mode shape so that the greatest shift of frequency can be achieved. For the thin plate immersed in heavyweight fluid, much greater additional mass should be added to obtain the required shift of frequency. Moreover, for the high-rank mode shape, mass blocks should be symmetrically laid at the wave peak of the structural mode shape. The further application study on frequency shift of thin plates on the basis of this study may be useful for altering natural frequency and reducing vibration in the modification of thin plate structure.

关 键 词：集中质量 薄板 移频 有限元 

分 类 号：TU433[建筑科学—岩土工程]