韧性硬化材料裂纹扩展分形运动2.doc

DOI：10.3901/JME.20**.**.*** 激励幅值对准零刚度隔振器特性的影响(二号黑体)* 刘兴天1, 2 黄修长1, 2 张志谊1, 2 华宏星1, 2(四号仿宋) (1. 上海交通大学振动、冲击、噪声研究所 上海 200240； 2. 上海交通大学机械系统与振动国家重点实验室 上海 200240) 摘要(小五，黑体)：提出具有负刚度特性的欧拉屈曲梁结构并分析其静态特性，将负刚度机构和线性隔振器并联使用，设计准零刚度隔振器。如果隔振器的载荷选用得当，系统将在零刚度点平衡，若载荷发生改变，系统平衡点将偏离零刚度点。考虑载荷的影响，对零刚度隔振器进行动态建模，并采用谐波平衡法求解准零刚度隔振器的响应。定义准零刚度隔振器平衡点不在刚度零点时系统的力传递率，分析激励幅值和载荷对隔振器性能的影响并和线性隔振器的性能进行比较。结果表明，所设计的零刚度隔振器具有低频隔振效果，其响应和隔振性能受到激励幅值和载荷的影响，可以使系统的特性从单纯的渐硬刚度向渐软刚度以及渐软-渐硬刚度混合的特性改变，并显著改变系统的传递性能。(小五，宋体) 关键词(小五，黑体)：负刚度 隔振 非线性系统 谐波平衡法(小五，宋体) 中图分类号(小五，黑体)：TG156(小五，Times New Roman) Influence of Excitation Amplitude and Load on the Characteristics of a Quasi-zero Stiffness Isolator(小三，加粗) LIU Xingtian1, 2 HUANG Xiuchang1, 2 ZHANG Zhiyi1, 2 HUA Hongxing1, 2(小四，姓大写) (1. Institute of Vibration, Shock and Noise, Shanghai Jiao Tong University, Shanghai 200240; (五号) 2. State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai 200240) Abstract(小五，加粗)：An Euler buckled beam formed negative stiffness mechanism is proposed and the static characteristic of which is analyzed. A quasi-zero stiffness isolator is designed by parallel connected the negative stiffness mechanism and a linear isolator. The Euler buckled beam structure functions as a stiffness corrector to lower the stiffness of the linear isolator. If the load is chosen properly, the equilibrium point will be set at the zero stiffness point, any changes of the load will lead the equilibrium point deviating from the zero stiffness point. The dynamic model is built considering the load effect and the Harmonic balance method is employed to solve for the dynamic response of the system. Force transmissibility of the zero stiffness isolator is defined and compared with that of an equivalent linear one. The effect of excitation amplitude and load on the performance is analyzed. The results show that the force excitation amplitude and load can change the characteristic of the nonlinear isolator from a hard