基于Poly IIR方法的简支梁振动模态分析与研究

VIBRATION MODAL ANALYSIS AND RESEARCH OF CANTILEVER BEAM BASED ON POLY IIR METHOD

分析某振动试验台简支梁的振动模态,首先利用弹性体一维振动理论得到简支梁的振动数学模型。然后利用伯努利-欧拉梁理论计算得到了简支梁振动微分方程,对简支梁设定特定的边界约束条件计算得到各阶模态参数,利用Workbench有限元仿真分析得到简支梁前五阶固有频率与振型,最后用基于Poly IIR的实验模态算法进行了简支梁实验模态参数识别,得到了简支梁横向与扭转模态频率与振型,验证了仿真值与实验值的一致性,最大误差为3%左右,可以为后续梁、板等弹性体复杂结构EMA分析研究提供一定的参考。

This paper analyses the vibration modes of a simply supported beam with vibration table. Firstly,the one dimensional vibration theory is used to acquire the beam vibration mathematical model. Following to use Bernoulli Euler beam theory to calculate the beam vibration differential equation,in addition to the beam set specific boundary constraint conditions to calculate each order modal parameters,using the Workbench beam finite element simulation analysis for the first five order natural frequency and vibration mode. In the end,the experimental modal algorithm based on Poly IIR is applied to identify the modal parameters of simply supported beam. The modal frequencies and mode shapes are obtained in this paper. It is keeping 3%about the consistency of the simulation value and experiment result,Which can subsequent beam or plate and so on EMA elastomer complex structure analysis and research to provide certain reference.