带惯容器的非线性隔振器对双层隔振系统动态特性影响分析

Study on Dynamic Characteristics Analysis of Nonlinear Double-stage Vibration Isolation Systems with Inerter

在高静低动刚度双层隔振器中引入惯容器,建立双层隔振系统动力学分析模型,利用谐波平衡法计算得到隔振系统动力学特性和传递特性,讨论惯容器惯容值、水平弹簧预压缩长度、刚度、阻尼系数等器件参数对隔振系统隔振性能的影响。研究结果表明,惯容器能够形成反共振频率,降低隔振器的共振频率,使得隔振器具有更低的隔振频段,进一步改善隔振器低频性能;同时惯容器对于减小隔振器的质量,实现隔振器轻量化设计也具有重要的积极意义。此外,非线性隔振系统较之对应的线性系统在隔振性能上也有更好的表现。

The dynamic model of a double-stage nonlinear vibration isolation system with high-static and low-dynamic stiffness and inerter was established. Vibration transmission and dynamic characteristics of this model were analyzed using harmonic balance method. Then, influences of element parameters, including inertance of the inerter, pre-compression length and stiffness of the horizontal spring, damping coefficient, on the vibration isolation performance were discussed. Numerical results show that the inerter element can yield anti-resonance frequency and reduce the resonant frequency of the isolation system so that the system has lower isolation frequency bend and its low-frequency performance is improved. Meanwhile,the inerter is of positive significance for reducing the mass of the isolator and realizing the lightweight design of isolators. In addition, the nonlinear vibration isolation system also has better performance of vibration isolation than that of the corresponding linear one.