双参数地基上输流管道的稳定性分析

Stability of Fluid-conveying Pipes Lying on Two-parameter Foundation

研究了双参数地基上两端铰支输流管道在定常内流作用时的静态稳定性和脉动内流作用时的动态稳定性问题。利用复模态方法计算了系统静态失稳临界流速,并应用平均法得到了脉动内流作用时管道的前两阶主参数共振区域,讨论了地基的线性刚度、剪切刚度及一些系统参数对临界流速和参数共振区域的影响。研究结果表明:改变两个地基刚度均可以影响系统的静态和动态稳定性,但剪切刚度的作用更显著,不能忽略;管道轴向预紧力、质量比、黏弹性系数及平均流速等参数也对系统稳定性有着不同的影响。

Static stability for constant inner flow and dynamic stability for pulsating inner flow of pinned--pinned pipes lying on two--parameter foundation were investigated. Applying a complex mode method,the critical flow velocity was calculated. For the case of pulsating inner flow, regions of principal parametric resonances for first two modes were obtained using the averaging method. The contributions of the linear, sheer foundation rigidities and some pipe parameters on the critical velocity and parametric resonance regions were discussed. The results demonstrate that variation of the two foundation rigidities can both influence the static and dynamic stabilities of the system, however the effect of the sheer rigidity is much greater than the linear rigidity and can not be neglected; the axial tension force, mass ratio, viscoelastic coefficient and mean flow velocity have some effects on the stabilities of the system.