准零刚度扭转隔振器振动传递特性研究

针对一种应用连杆弹簧负刚度结构所设计的正负刚度并联扭转隔振器，通过分析其设计参数，得到了其在静平衡位置达到准零刚度的条件。针对所述系统，建立二自由度非线性动力学微分方程，应用谐波平衡法求解了准零刚度隔振器的振动响应。考虑激励幅值、系统阻尼和转动惯量等因素，从扭转振动力矩传递和扭转振动功率流传递两个角度分析了准零刚度隔振系统的非线性振动传递特性。结果表明，此隔振系统具有良好的低频隔振效果，且表现为振动传递的硬特性；从功率流角度的分析还表明，系统的瞬时传递功率流峰值与输入功率流和耗散功率流的变化趋势保持一致。在低于共振区域的低频区间内，隔振系统前后两端的转动惯量对系统振动具有较大影响。最后，对扭转隔振器的振动隔离特性进行了试验验证，试验结果表明，隔振器具有良好的低频振动隔离特性。

Vibration Transmission Characteristics of a Quasi-zero Stiffness Torsional Isolator

A torsional isolator with negative stiffness structures is proposed and the quasi-zero stiffness characteristic is got by analyzing the design parameters of this isolation system. The two-degree freedoms dynamic model is built and the harmonic balance method is employed to solve for the dynamic response of the system. Considering the influence of amplitude, damping, and rotational inertia of the isolation system, the torque transmission and vibration power flow characteristics are investigated to examine the performance of this nonlinear isolator. The results show that this torsional isolator has good low-frequency isolation performance and hardening stiffness nonlinearity. From the analysis of the power flow behavior, the results show that there has a good correlation between input power flow, dissipated power flow and instantaneous transmitted power flow. Rotational inertia has great influence to the vibration performance of system in the low frequency away from the peak frequency regions. Finally, the vibration isolation characteristics of the torsional vibration isolator are tested. The experiment results show that the isolator has good isolation characteristics of low frequency vibration.