摘要
实际工程中,碟簧类隔振器常简化为线性模型,随着隔振器内部碟簧数量的增加,边界摩擦效应与刚度阻尼非线性等问题导致线性模型失真。为了研究对合碟簧组在考虑边界摩擦条件下的非线性振动特性,提出了一种含有预紧的对合碟簧隔振单元,建立了考虑边界摩擦与预紧条件下对合碟簧组的非线性动力学模型。应用Klotter求解非线性方程的方法,对该对合碟簧隔振单元在基础激励下的受迫振动进行分析计算,得到其固有频率附近的幅频特性曲线方程;基于RouthHurwitz稳定性判定条件,推导并计算出该对合碟簧隔振单元的不稳定区间,并讨论系统参数对该隔振单元非线性振动与稳定性的影响。计算结果表明,幅频特性曲线与稳定区间均仅由系统的非线性刚度三次项无量纲系数α2、黏性阻尼无量纲系数μ1与附加支持力无量纲系数μ2控制,且系统脱离频率Ωb的平方与附加支持力无量纲系数μ2成正比。系统存在异常跳跃状态与不向稳定共振分支跳跃的微共振或无共振状态,并说明了黏性阻尼无量纲系数μ1与附加支持力无量纲系数μ2对这两种状态以及其稳定区间的影响关系。最后,通过定频试验验证模型的准确性。
Disc spring vibration isolators are often simplified as linear models in practical engineering.With the increase of the number of disc springs in the isolator,the boundary friction effect and nonlinear stiffness and damping problems lead to the distortion of the linear model.In order to study the nonlinear vibration characteristics of opposed disc springs with boundary friction,a vibration isolator with opposed disc springs of pre-tightening is proposed.A nonlinear dynamic model of this vibration isolator under considering boundary friction and pre-tightening is established.Klotter’s method is applied to solve the nonlinear equations,and the forced vibration of the vibration isolator with opposed disc springs under based excitation is analyzed and calculated.Based on Routh-Hurwitz stability criteria,the instability interval of the vibration isolator with opposed disc springs is deduced and calculated.The influence of the system parameters on the nonlinear vibration and stability interval of the vibration isolator is also discussed.The results show that the amplitude-frequency characteristic curve and the stability interval are only influenced by the nonlinear stiffness cubic coefficient α_(2),viscous damping coefficient μ_(1) and additional support force coefficient μ_(2) of the system.And the square of break-loose frequency Ω_(b) of the system is proportional to the additional support force coefficient μ_(2).The system with opposed disc springs exists abnormal jump and non-resonance state which does not jump to stable resonance branch.And the relationship between viscous damping coefficient,additional supporting force coefficient on those two states and their stable intervals are explained.The accuracy of the model is verified through fixed frequency tests.
作者
闫明
惠安民
孙自强
张晓友
王开平
刘海超
YAN Ming;HUI An-min;SUN Zi-qiang;ZHANG Xiao-you;WANG Kai-ping;LIU Hai-chao(School of Mechanical Engineering,Shenyang University of Technology,Shenyang 110870,China)
出处
《振动工程学报》
EI
CSCD
北大核心
2021年第6期1230-1239,共10页
Journal of Vibration Engineering
基金
辽宁省‘兴辽英才计划’项目(XLYC1802077)。
关键词
非线性振动
隔振
对合碟簧
边界摩擦条件
振动稳定性
nonlinear vibration
vibration isolation
opposed disc springs
boundary friction condition
vibration stability
