粘弹性输流管道混沌运动的多模态分析

讨论了两端固支输流管在其基础简谐运动激励下的稳定性及混沌运动·考虑管道变形的非线性因素 ,推导了管道的非线性运动方程 ,运用Melnikov方法确定了管道系统发生混沌运动的激励振幅临界值 ,同时还利用分岔图等数值模拟方法分别对单、双模态下系统的运动形态进行了研究 ,并将不同模态下的结果进行了比较·结果表明 ,高阶模态对单模态位移具有定量的补充 ,但不会改变系统动态行为的基本特性·

Multi-Mode Analysis of Chaotic Motions of a Viscoelastic Pipe Conveying Fluid

The stability and chaotic motion of a pipe conveying fluid with both ends fixed, excited by the harmonic motion of its supporting base in a direction normal to the pipe span, were investigated theoretically. The nonlinear differential equation of the system motion was derived by considering the additional axial force due to lateral motion of the pipe. Melnikov method was used to predict the initiation of chaotic motion of the system. The critical value was found to be smaller than that determined by numerical simulation. The motions of both single-mode and two-mode systems were analyzed by means of numerical simulations. The high-order mode of the system can quantitatively complement the displacement of the single-mode system.