基于顶部张紧式立管动力分析的关键参数研究

文中提出了一种适用于工作于南中国海张力腿平台(TLP)的顶张紧式立管(TTR),并利用有限元软件ABAQUS/AQUA对该立管进行了模拟分析,计算用以预测立管波浪飞溅区和立管下部区域在波浪以及平台联合作用下的影响。计算时采取时域计算方法,计算过程中考虑了几何非线性的影响。并在计算完成TTR在位动力分析的基础之上,做了一定量的参数敏感性分析,重点考察立管侧向位移,弯矩以及等效应力水平对TTR一些重要参数的敏感性。结果表明,计算顶张力TTR动力分析时,必须考虑平台侧向位移跟轴向位移的耦合作用,立管响应受其顶部TLP平台以及张力比TTF的影响较大。随着立管顶部张力比TTF的增加,立管的变形逐渐变小,但顶部张力的增加同时增加了立管内部的等效应力,立管设计时应充分考虑到这两者之间的"平衡"关系。

Effect of Several Key Parameters on the Dynamic Analysis of TTR

A production Top Tensioned Riser(TTR) system is proposed for a Tensioned Leg Platform(TLP) designed to work in South China Sea at a water depth up to 1 500 m.3D FE model of the riser is simulated by ABAQUS/AQUA.The effect of geometric nonlinearity is considered and time domain analysis method is used to predict the response in the splash zone and lower portion of the production riser.Detailed responses for displacement,bending moment and stress are given for the further investigation of dynamic effects by crucial parameters,such as,Top Tension Factor(TTF) and motion of the TLP.This paper also presents further studies on the sensitivity of each parameter to the response of the TTR.The results show that while the increase of the top tension reduces riser deflection,simultaneously it increases the equivalent stress of the riser,and TLP motion greatly affects the behavior of the riser.A good design of the riser should be a ‘balance’ between the top end and the bottom end.