水流作用下含单个裂纹悬空输油管道数值分析

Numerical analysis of underwater suspended pipes with one crack flaw

分析水流作用下悬空管道的载荷类型和悬空方式,并计算各悬空状态下管道最大弯矩;划分裂纹周围有限元网格,并计算裂纹位置、跨度、裂纹所处角度对管道峰值应力影响;分析裂纹尺寸、管道内压力和管道外部水流绕流所产生的激振力对管道应力和疲劳寿命的影响.结果表明,对水流作用下含单个裂纹悬空管道,水流激振力对管道峰值应力和疲劳寿命影响最大.

The loads and suspended manners of underwater pipes have been analyzed,and the maximum moments are obtained under each suspended state.Finite element mesh is reasonably divided.On the basis of that,the influence of many factors is achieved on the peak stress in the pipe,such as crack location,span and crack position,also the crack location,span and crack position for follow-up study are determined.After that,the influence of the other factors is analyzed on the peak stress and fatigue cycles,including crack sizes,internal pressure and flow over exciting force.The result shows that the fluid exciting force produces the biggest effect on peak stress and fatigue life in underwater pipes with one circumferential crack flaw.