考虑结合面影响的组合梁非线性预应力模态分析  

Nonlinear pre-stressed modal analysis for a composite beam considering influence of joint surface

作　　者：李小彭[1] 赵光辉[1] 杨皓天 闻邦椿[1] 

机构地区：[1]东北大学机械工程与自动化学院,沈阳110819

出　　处：《振动与冲击》2014年第4期17-21,共5页Journal of Vibration and Shock

基　　金：国家自然科学基金(51275079);中央高校基本业务费专项科研基金(N110403009);新世纪优秀人才支持计划(NCET-10-0301)资助项目

摘　　要：为了研究结合面非线性特性对机械结构动态性能的影响,利用有限元分析软件,以组合梁结合面为研究对象,首先进行了考虑结合面非线性特性的非线性预应力模态分析,证明了结合面非线性特性对组合梁各阶弯曲振动固有频率有重要影响;然后采用单变量法研究了结合面法向载荷和摩擦系数对组合梁振动特性的影响。研究表明:结合面的法向载荷和摩擦系数都会使组合梁的固有频率降低,其中摩擦系数占主导地位。摩擦系数对组合梁低阶固有频率影响较小,高阶时影响较大。最后进行模态试验验证,实验表明:模态试验所得组合梁弯曲振型与非线性预应力模态分析法所得振型相吻合,且二者所得固有频率之间的误差在接受范围之内,从而证明了非线性预应力模态分析的可行性。In order to consider the influence of nonlinear characteristics of a joint surface on the dynamic characteristics of a whole machine,a composite beam was taken as a study object,and the nonlinear pre-stressed modal analysis method was used based on ANSYS.The nonlinear characteristics of its joint surface were proved to have an important influence on the bending natural frequencies of the composite beam.Moreover,the influence of normal load and friction coefficient of the joint surface on the natural frequencies was studied with the single variable method.The results showed that the natural frequencies of the beam decrease due to normal load and friction coefficient,and friction coefficient is dominant.Finally,the modal test was conducted.It was shown that the modal shapes of the composite beam obtained from the modal test are coincided with those gained from the nonlinear pre-stressed modal analysis;the error between the corresponding natural frequency obtained from the two cases is in an acceptable range.The results proved the feasibility of the nonlinear pre-stressed modal analysis method.

关 键 词：组合梁 结合面 非线性预应力模态分析 模态试验 

分 类 号：TH113.1[机械工程—机械设计及理论]