【作者】 娄敏；

【导师】 郭海燕；

【作者基本信息】 中国海洋大学 ， 防灾减灾工程及防护工程， 2005， 硕士

【摘要】 海底管线是海上油田的生命线,海洋油田油、气、水的集输、贮运,多是通过海底管线来完成,海底管线把海上油田的整个生产密切地联系起来。本文以海底管道悬跨段为研究对象,阐述了当管外流体流经管道时产生涡激振动的机理及其相关影响参数,推导了海底管道悬跨段在管外环境荷载作用下和管内流体流动状态下的振动微分方程,考察了不考虑阻尼和考虑阻尼两种情况下海底管道悬跨段的动力特性,并以不发生涡激振动为控制条件,推导出海底管道允许悬跨长度;为考察海底管道悬跨段的动力响应,将尾流振子模型与海底管道悬空段振动微分方程相结合,得到管道与流体的耦合振动方程,用有限元法及迭代法进行求解,得到管道涡激振动响应。结果表明:在相同的情况下,考虑阻尼的海底管道允许悬跨长度低于不考虑阻尼的海底管道允许悬跨长度,但差别不大;管道允许悬空长度随着内流流速、轴向压力和管内压强的增加而减小,随着轴向拉力的增加而加大;管内流体流动使得涡激共振向低频方向偏移并使响应峰值有所降低,内流对涡激振动的影响随着悬空长度的增加而增加,随着轴向拉力的增加而降低。更多还原

【Abstract】 Submarine pipelines are the lifelines of marine oil fields. The transportations of oil, gas and water in the marine oil field are almost accomplished by the submarine pipelines. So it is the submarine pipelines that make the marine oil field contact closely.This paper mainly focuses on the Vortex-Induced Vibration (VIV.) of submarine free spanning pipelines. The generating mechanism as well as properties and related parameters of VIV are expressed. The partial differential equation for the response of a marine pipeline considering the effect of the internal flowing fluid and the external marine environmental condition is derived. The dynamic characteristics without considering damping and considering damping are both analyzed, then using reduced velocity as a control parameter, derives the allowable span length of submarine pipelines. In order to find the dynamic response of the free span, combining Matteo Luca Facchinetti’s wake oscillator model with the differential equation of the free span to get the coupling equations between pipe and fluid, the finite element method combined with the simple iteration is used to solve the system of equations. The results indicate that: in the same case, the allowable span length considering damping is a little small than that without considering damping, the allowable span length of the submarine pipelines decreases with an increment in the velocity of internal flow, compression and pressure , increases with an increment in tension ; the flowing of internal fluid may cause the resonant bands shift to the lower frequency as well as a slight decrease in the peak value, the effect will be more pronounced with the increase of the span length and can be weaken by the presence of the axial tension.更多还原