摘要
根据历年检测资料可知杭州湾海底管道某些管段存在不同程度悬跨现象,管跨涡激振动是引发海底管道疲劳失效的主要因素之一。根据杭州湾海底管道所在海域底层流速检测数据,近似估算杭州湾海底管道所在海域底层流速分布,利用FLUENT模拟管跨涡激升、曳力,在ANSYS中建立管土耦合非线性有限元模型,依据Miner线性累积损伤理论,采用雨流计数和S-N曲线法计算管跨在海流作用下的疲劳损伤和疲劳寿命,分析管道疲劳损伤影响因素并提出工程对策。研究结果表明,杭州湾海底管道所在海域底层流速服从正态分布,带阻流板管道涡激升力存在严重非对称性,管跨危险节点均位于管跨中点,杭州湾海底管跨疲劳损伤对海底流速最为敏感,跨长次之,跨长和流速是管跨结构疲劳损伤的主导因素,土壤剪切强度及输送介质温度对管道疲劳损伤的影响不明显。
According to survey data collected in recent years,it is recognized that the suspended span phenomenon to varying degrees occurs in some parts of Hangzhou Bay subsea pipelines.The vortex-induced vibration(VIV)of pipeline span is one of the main factors that result in fatigue failure of subsea pipelines.On the basis of the bottom current velocity data of sea areas with Hangzhou Bay subsea pipelines,the bottom current velocity distribution of sea areas with Hangzhou Bay subsea pipelines was estimated.In addition,FLUENT software was used to simulate the vortex-induced lift and drag forces of the pipeline span,and a non-linear pipe-soil coupling finite element model was developed in the ANSYS system.According to the Miner linear cumulative damage theory,the fatigue damage and life of the pipeline span under the action of sea currents were calculated through rain-flow counting and S-N curve methods,and the influencing factor of pipeline fatigue damage was analyzed,with engineering countermeasures proposed.The results show that the bottom current velocity of sea areas with Hangzhou Bay subsea pipelines obeys normal distribution,and the vortex-induced lift force of pipelines with spoilers is severely asymmetric.Furthermore,the dangerous points are all located at the midpoint of the pipeline span.The fatigue damage of Hangzhou Bay subsea pipelines with a suspended span is the most sensitive to the bottom current velocity,with the span length taking second place.The span length and current velocity are the main factors resulting in structural fatigue damage of the pipeline span,while the shear strength of soil and temperature of transmitted media have a slight influence on the fatigue damage of pipelines.
作者
曹国民
CAO Guomin(PipeChina Eastern Crude Oil Storage&Transportation Co.,Ltd.,Xuzhou 221008,China)
出处
《石油工程建设》
2022年第6期18-22,27,共6页
Petroleum Engineering Construction
关键词
海底管道
悬跨
管土耦合
涡激振动
疲劳寿命预测
敏感分析
subsea pipelines
suspended span
pipe-soil coupling
vortex-induced vibration
fatigue life prediction
sensitivity analysis
