摘要
基于得到的水平悬臂输液管非线性动力学控制方程,详细研究了由流速最小临界值诱发的3∶1内共振.通过观察内共振调谐参数、主共振调谐参数和外激励幅值的变化,发现在内共振临界流速附近,流速导致系统出现模态转换、鞍结分岔、Hopf分岔、余维2分岔和倍周期分岔等非线性动力学行为,对应的管道系统的周期运动失稳出现跳跃、颤振和更加复杂的动力学行为.通过理论结果与数值模拟比较,表明了理论分析的有效性和正确性.
The Newtonian method is employed to obtain nonlinear mathematical model of motion of a horizontally cantilevered and inflexible pipe conveying fluid, The Order magnitudes of relevant physical parameters are analyzed qualitatively to establish a foundation on the fuither study of the model. The method of multiple scales is used to obtain eigenfunctions of the linear flee-vibration modes of the pipe. The boundary conditions yield the characteristic equations from which eigenvalues can be derived. It is found that flow velocity in the pipe may induced the 3:1, 2: 1 and 1 : 1 internal resonances between the first and second modes such that the mechanism of flow-induced internal resonances in the pipe under consideration is explained theoretically. The 3:1 internal resonance first occurs in the system and is, thus, the most important since it corresponds to the minimum critical velocity.
出处
《应用数学和力学》
CSCD
北大核心
2006年第7期819-824,共6页
Applied Mathematics and Mechanics
基金
国家自然科学基金资助项目(10472083)
国家自然科学基金(重点)资助项目(10532050)
关键词
输液管
内共振
稳定性
分岔
pipe conveying fluid
internal resonance
stability
bifurcation