基于非线性吸能机理的涡激振动减振理论与实验研究  

THEORETICAL AND EXPERIMENTAL STUDY ON VORTEX-INDUCED VIBRATION SUPPRESSION BASED ON NONLINEAR TARGETED ENERGY TRANSFER

作　　者：陆子 何毅翔 张岚斌 代胡亮 王琳 Lu Zi;He Yixiang;Zhang Lanbin;Dai Huliang;Wang Lin(School of Aerospace Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment,Wuhan 430074,China)

机构地区：[1]华中科技大学航空航天学院,武汉430074 [2]工程结构分析与安全评定湖北省重点实验室,武汉430074

出　　处：《力学学报》2022年第11期3147-3156,共10页Chinese Journal of Theoretical and Applied Mechanics

基　　金：机械系统与振动国家重点实验室开放基金资助项目(MSV202205)。

摘　　要：流致振动现象广泛存在于机械、航空、土木和石油等重要工程领域,为防止工程结构因流致振动行为而造成疲劳破坏,有必要对稳定性、动力学响应及其振动控制做深入研究.本文提出了一种由弹簧和质量块构成的非线性吸能器(nonlinear targeted energy transfer, NTET),研究了该非线性吸能器对弹性支承圆柱体涡激振动的被动控制影响机制.基于能量法推导了圆柱体涡激振动非线性被动控制的耦合动力学方程,通过设计非线性弹簧-质量块构型的NTET,进一步开展了涡激振动控制的实验研究,并与理论预测结果进行了较好的对比,获得提升涡激振动控制效果的最佳参数值.研究发现, NTET的质量、弹簧刚度以及弹簧预应力等参数会对涡激振动控制效果产生显著的影响.本文研究结果表明,该耦合系统中圆柱体和NTET均表现出周期性的稳态振动响应, NTET质量的改变会显著影响系统的耦合频率.在无预应力状态下, NTET质量越大、刚度越小时,有更好的减振效果.当弹簧预应力逐渐增大时, NTET的非线性刚度逐渐变弱,会降低涡激振动控制性能.参数分析表明:随着涡激振动控制性能的提升,圆柱体的振幅逐渐较小, NTET的振幅逐渐增大,能量传递效率逐渐提高.研究结果可为工程中涡激振动控制策略的高效设计提供有用的理论支撑和实验数据.Flow-induced vibration of the structure widely occurs in many important engineering fields such as mechanical, aerospace, civil and petroleum. In order to prevent fatigue and failure of the engineering structures due to flow-induced vibrations, it’s necessary to do deep researches on stability, dynamic responses and vibration controls. In this paper, a nonlinear targeted energy transfer(NTET) model composed of linear springs and mass block is proposed.The passive control mechanism of nonlinear energy absorbers on the vortex-induced vibration of an elastically supported cylinder is investigated. Firstly, based on the energy method, the coupling dynamic equations for the nonlinear passive control on vortex-induced vibration of a cylinder are established. Then, experimental study is conducted by designing the nonlinear spring-mass configuration of NTET. Good agreements are obtained by comparing experimental results with theoretical predictions. Finally, the optimal parameters of the NTET for improving the control performance of vortex-induced vibrations are obtained. It is found that some NTET parameters such as mass, spring stiffness and spring prestress have significant impacts on the control performance. The results show that both the cylinder and NTET exhibit periodic steady-state vibration responses. Changes in the mass of NTET can significantly affect the coupling frequency of the system. In the case of no spring prestress, larger mass, lower stiffness of the NTET can produce a better vibration suppression. But when the spring prestress is increased, the nonlinear stiffness of the NTET becomes weak, resulting in a reduction of control effect on the vortex-induced vibration. Parametric analysis shows that with the enhancement of vortex-induced vibration control effect, the vibration amplitude of cylinder can be decreased while the NTET’s amplitude is gradually increased, indicating the improvement of the energy transfer efficiency. The present research results can provide very useful theoretical support and

关 键 词：涡激振动 非线性吸能器 非线性振动控制 锁频区域 

分 类 号：TB126[理学—工程力学]