外部液动力作用下管道输送流固耦合应力分析

采用计算流体动力学方法分析管道-外部流体相互耦合效应对管道连接点应力影响。以垂直输送管道系统为研究对象，应用数值方法求解外部流体-管道进行流固耦合这一非线性问题。研究结果表明：1)扬矿硬管上端无论是固接还是铰接，外部流场以不同速度冲击管道，应力集中出现在管道靠近连接区域，最大应力也出现在管道连接点处，其余部位管道应力变化较小；2)其最大等效应力随着外部流场速度增大而增大，以固接方式连接产生的管道最大等效应力总是大于以铰接方式连接的最大等效应力。3)当外部流体速度为0.9m/s时，两种连接产生的最小应力值在该流速点均出现局部极小值，且固接时局部极小应力小于铰接时的局部极小应力。

STRESS ANALYSIS ON FLUID-SOLID COUPLING EFFECTS FOR VERTICAL LIFTING PIPE

Computational fluid dynamics methods were used to analyse the influence of the fluid-structure interaction (FSI) between pipe and external fluid coupled system. The vertical pipeline system was investigated, and the interaction between the external fluid and pipe was solved with the application of numerical methods for the nonlinear fluid-structure problem. These results were shown that: 1) whether the connection modes of lifting pipe on top end were fixed or hinged, the impact of the external flow field at different speeds on pipe brought the concentrated stress in the location close to the connection area. The maximum stress appears at the top of the pipe connection point while the stresses of the remaining parts in the pipeline had little fluctuations; 2) its maximum equivalent stresses were increased with the external flow velocity up. The values of the pipe’s maximum stresses produced by a fixed connection were always greater than that of the hinged connection. 3) in despite of fixed or hinged connection, local minimum stress appears when the external fluid velocity is 0.9m/s. In contrast, the local minimum stress value generated by the fixed support was less than that by hinged connection .