| Related citation: | Rui Zhong,Jian’en Chen,Weimin Ge,Jun Liu,Xiaofeng Wang.Vibration Absorption Efficiency and Higher Branches Elimination of Variable-Stiffness Nonlinear Energy Sink[J].Journal of Harbin Institute Of Technology(New Series),2020,27(1):76-84.DOI:10.11916/j.issn.1005-9113.18067. |
|
| Author Name | Affiliation | | Rui Zhong | Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, Tianjin University of Technology,Tianjin 300384, China
National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin 300384, China | | Jian’en Chen | Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, Tianjin University of Technology,Tianjin 300384, China
National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin 300384, China | | Weimin Ge | Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, Tianjin University of Technology,Tianjin 300384, China
National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin 300384, China | | Jun Liu | Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, Tianjin University of Technology,Tianjin 300384, China
National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin 300384, China | | Xiaofeng Wang | Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, Tianjin University of Technology,Tianjin 300384, China
National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin 300384, China |
|
| Abstract: |
| Vibration absorption efficiency of a variable-stiffness nonlinear energy sink (NES) was investigated when the main oscillator was subjected to harmonic and impulse excitations. The slow flow equations of the coupled system were derived by using the complexification-averaging method, and the nonlinear equations which describe the steady-state response were obtained. As the harmonic excitation force increased, the system which comprises constant-stiffness NES generated higher branch responses, greatly reducing the vibration absorption efficiency. The influence of nonlinear stiffness on the responses of the system was investigated. Results show that, with the increase of harmonic exciting force, a reduction of NES stiffness can eliminate the higher branch responses and even the frequency band of strongly modulated responses. The vibration absorption efficiency of variable-stiffness NES attached to the linear oscillator for different amplitudes of impulse excitation was investigated. Results show that the proper reduction of nonlinear stiffness under increasing impulse excitation can greatly increase the vibration absorption efficiency of NES, and the variable-stiffness design can effectively mitigate the negative influences of the increase of the excitation amplitude on the efficiency of constant-stiffness NES. |
| Key words: nonlinear energy sink efficiency variable-stiffness vibration suppression higher branch |
| DOI：10.11916/j.issn.1005-9113.18067 |
| Clc Number:O322 |
| Fund: |
|
| Descriptions in Chinese: |
| 变刚度非线性能量阱的吸振效能及高分支响应抑制研究 钟锐1,2，陈建恩1,2*，葛为民1,2，刘军1,2，王肖锋1,2 （1.天津理工大学 天津市先进机电系统设计与智能控制重点实验室，天津 300384；2.天津理工大学 机电工程国家级实验教学示范中心，天津 300384) 创新点说明：非线性能量阱只能在一定输入能量范围内保持吸振效能，本文提出一种可变刚度的非线性能量阱，根据外部激励大小，合理改变其刚度可以消除高分支响应，并且可以使系统呈现强调制响应，提高吸振效能。 研究目的： 消除连接非线性能量阱的系统在大幅激励下的高分支响应，并在激励大范围变化的环境下提高非线性能量阱的吸振效能。 研究方法： 1）使用复变量-平均法推导出连接变刚度非线性能量阱的系统的慢变动力学模型 2）使用龙格-库塔法验证所推导出的近似模型的准确性。 3）使用Maple和MATLAB软件求出系统在不同幅值的简谐和冲击载荷激励下的系统响应。 研究结果： 1）简谐激励幅值增大后系统频响出现了高、低两个分支，随着激励幅值的进一步增大，高、低分支合并，使非线性能量阱接近失效。通过使用变刚度非线性能量阱，合理减小非线性能量阱的刚度可以消除高分支，降低主振子振幅。 2）在系统即将出现高分支响应之前，随着简谐激励幅值增加，系统固有频率附近的不稳定解的频带会变宽。 3）在冲击激励下，使用合理调整刚度后的变刚度非线性能量阱，相比于普通定刚度非线性能量阱，可以较大幅度提高系统的能量耗散率。 结论： 使用变刚度设计的非线性能量阱可以通过合理减小刚度来消除由外部激励幅值增大而产生的高分支响应，从而使其在更宽的输入能量变化范围内保持较高的吸振效能。值得注意的是，有利于吸振的强调制响应对应的频带加宽到一定程度后，系统会产生高分支响应，因此，应该控制非线性能量阱的刚度以使系统的强调制响应处于较窄的频带内。 关键词：非线性能量阱；吸振效能；变刚度；振动抑制；高分支 |
