海洋工程中双柔性圆柱流激振动响应特性  

Flow-induced vibration response of two flexible cylinders in ocean engineering

作　　者：徐万海[1] 李宇寒 闫术明[2] 马烨璇 XU Wanhai;LI Yuhan;YAN Shuming;MA Yexuan(State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, China;China Petroleum Pipeline Engineering Corporation, Langfang 065000, China)

机构地区：[1]天津大学水利工程仿真与安全国家重点实验室,天津300072 [2]中国石油天然气管道工程有限公司,河北廊坊065000

出　　处：《海洋工程》2020年第2期8-16,共9页The Ocean Engineering

基　　金：国家自然科学基金(51679167,51608059)。

摘　　要：海洋立管、海底管线和浮式平台系泊缆等柔性圆柱结构的流激振动会造成严重的疲劳损伤。目前,关于单根柔性圆柱流激振动的研究较多。为研究多根柔性圆柱系统的流激振动特性,开展了双柔性圆柱流激振动的模型试验。采用模态分析法将试验测量应变转化为位移。通过分析双柔性圆柱在并列、串列和交错排布方式下的响应位移、控制频率,揭示了双柔性圆柱的流激振动特性。研究结果表明:柔性圆柱并列排布时,两圆柱的相互作用使结构顺流向位移增大;柔性圆柱串列排布时,受遮蔽效应的影响,下游圆柱控制模态较低。由于柔性圆柱的多模态响应特性,“锁频”区后下游圆柱的位移并未显著增大;柔性圆柱交错排布时,下游圆柱发生“Wake-flutter”,横流向和顺流向的控制频率接近,顺流向的位移显著增大。Flow-induced vibration(FIV)of the flexible cylindrical structures such as marine risers,pipelines and mooring lines of platforms causes severe fatigue damage.Numerous researches have been conducted upon FIV of the isolated flexible cylinder till now,however little attention has been paid to the FIV characteristic of multiple flexible cylinders.In order to study FIV of multi-cylinders,model tests on FIV of two flexible cylinders is performed.Besides,modal analysis is employed to reconstruct the strain obtained from the tests into the displacement.By analyzing displacement response and dominant frequency of two flexible cylinders in side-by-side,tandem and staggered configurations,FIV characteristics of two flexible cylinders are revealed.The result shows that the in-line(IL)displacements of two cylinders in a side-by-side arrangement increase under the interaction between them.The dominant mode of the downstream cylinder is low due to the shadowing effect when two cylinders are arranged tandem.The displacement of the downstream cylinder is not significantly increased after the“lock-in”region on account of the multi-modal response of the flexible cylinder.When flexible cylinders are staggered,the“wake-flutter”occurs to the downstream cylinders.The dominant frequency in cross-flow(CF)is similar to that in IL and the displacement in IL is remarkably increased.

关 键 词：双柔性圆柱 流激振动 响应位移 控制频率 排列方式 

分 类 号：P751[交通运输工程—港口、海岸及近海工程]