基于Hertz模型的海洋立管束碰撞力计算方法研究  

Calculation method for collision force of marine riser bundles based on Hertz model

作　　者：徐万海[1] 李航[1] 贺子琪 XU Wanhai;LI Hang;HE Ziqi(State Key Lab of Hydraulic Engineering Intelligent Construction and Operation,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学,水利工程智能建设与运维全国重点实验室,天津300072

出　　处：《振动与冲击》2024年第13期248-253,314,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(51979163,U2106223)。

摘　　要：立管是海洋油气开采的关键设备之一,其在流致振动作用下,相邻立管可能会发生振动碰撞损伤。基于Hertz模型,针对不同夹角下的两根立管碰撞的碰撞力计算开展研究。借助有限元方法探讨海洋立管局部碰撞过程,立管的直径选取为工程应用较为广泛的30.48 cm,截取长度基于相关碰撞参与长度来确定,径厚比范围为16~60,分别设置立管碰撞时的速度为0.25 m/s、1.5 m/s、2.4 m/s和3 m/s,分析两根立管夹角和立管径厚比等对于Hertz模型计算精度的影响。研究发现:两根立管夹角越小和径厚比越小,Hertz模型得到的碰撞力误差越大;通过在Hertz模型中添加与径厚比相关的系数,对Hertz模型进行了修正,最终得到了关于立管束碰撞力的精确计算方法。Risers are one of key equipment for offshore oil and gas extraction.Under action of flow induced vibration,adjacent risers may have vibration collision damage.Here,based on Hertz model,calculation of collision force between two vertical pipes at different angles was studied.The finite element method was used to explore local collision process of marine risers,riser diameter was selected as 12 inches widely used in engineering,riser length was determined based on the relevant collision participation length,and the diameter to thickness ratio was within the range of 16~60.The velocities of riser during collision were set to 0.25 m/s,1.5 m/s,2.4 m/s and 3 m/s,respectively.Effects of angle between two risers and the diameter to thickness ratio of riser on calculation accuracy of Hertz model were analyzed.The study showed that the smaller the angle between two risers and the smaller the diameter to thickness ratio,the larger the collision force error obtained with Hertz model;Hertz model is modified by adding a coefficient related to the diameter to thickness ratio into the model,and an accurate calculation method for collision forces of riser bundle is ultimately obtained.

关 键 词：立管碰撞 Hertz模型 有限元模拟 接触力法 

分 类 号：TU311.3[建筑科学—结构工程]