Numerical study of vibrations of a vertical tension riser excited at the top end  

作　　者：Bowen Fu Decheng Wan 

机构地区：[1]State Key Laboratory of Ocean Engineering,School of Naval Architecture,Ocean and Civil Engineering,Shanghai Jiao Tong University,Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration,Shanghai 200240,China

出　　处：《Journal of Ocean Engineering and Science》2017年第4期268-278,共11页海洋工程与科学（英文）

基　　金：This work is supported by the National Natural Science Foundation of China(51490675,51379125,11432009,51579145);Chang Jiang Scholars Program(T2014099),Shanghai Excellent Academic Leaders Program(17XD1402300);Program for Professor of Special Appoint-ment(Eastern Scholar)at Shanghai Institutions of Higher Learning(2013022);Innovati ve Special Pro ject of Numerical Tank of Ministry of Industry and Information Technology of China(2016-23/09);Lloyd’s Register Foundation for doctoral student,to which the authors are most grateful.

摘　　要：This paper presents numerical simulations of vortex-induced vibrations of a vertical riser which is sinusoidally excited at its top end in both one and two directions in still water.A computational fluid dynamics method based on the strip theory is used.The riser’s responses to both top-end and two-end excitations are carefully examined.In low reduced velocity cases,the in-line vibrations consist of three components,the low-frequency oscillation,the first-natural-frequency vibration during the riser reversal,and the second-natural-frequency vibration due to vortex shedding.The sheared oscillatory flow along the span causes low-frequency oscillations in higher modes in the in-line direction,thus forming‘X’shaped,‘II’shaped,and‘O’shaped trajectories at various positions along the span when the riser is excited at its top end in one direction.In the presence of excitations in the other direction,more complex trajectories appear.

关 键 词：Vortex-induced vibration Oscillatory flow RISER Platform motion Viv-FOAM-SJTU solver 

分 类 号：TQ0[化学工程]