X型准零刚度隔振器的隔振特性分析

Vibration Isolation Characteristics Analysis of X-shaped Quasi-Zero Stiffness Vibration Isolator

将一种X型结构应用于准零刚度隔振器以改善其低频隔振性能.根据牛顿运动定律建立了系统的动力学方程.利用增量谐波平衡法对非线性常微分方程进行求解,得到系统的幅频响应曲线.讨论了等同约化刚度γ值对系统传递率的影响.研究结果表明:水平弹簧的无量纲预压缩长度的合理区间为(0,2).在共振区时,γ值的增大可以减小力传递率.在较高频率激励下,γ值的变化对系统隔振性能影响较弱.随着γ值减小,共振区的位移传递率急剧减小.此外,γ值的减小也会引起共振频率减小,并且使得跳跃现象消失.因此,X型准零刚度隔振器的等同约化刚度γ值是一个可以有效反映系统低频隔振效果的理想参数.

An X-shaped structure is applied to quasi-zero stiffness isolator to improve its low frequency isolation performance.The dynamic equation of the system is established by using the Newton’s motion law.The amplitude-frequency response curves of the system are obtained by using the incremental harmonic balance method.The effect of equivalent reduced stiffnessγon system transmissibility is discussed.Research results show that the reasonable numerical interval of dimensionless pre-compression length of horizontal spring is(0,2).In the resonant region,the increase ofγcan significantly reduce the force transmissibility.At higher excitation frequencies,the effect of the change ofγon the vibration isolation performance of the system is weak.With the decrease ofγ,the displacement transmissibility in the resonance region decreases sharply.In addition,the decrease ofγwill also reduce the resonance frequency and make the jump phenomenon disappear.Therefore,the equivalent reduced stiffnessγof the X-shaped quasi-zero stiffness isolator is an ideal parameter which can effectively reflect the effect of low-frequency vibration isolation of the system.The effect of equivalent reduced stiffnessγis discussed in detail.