立柱直径比对四立柱平台涡激运动性能影响的数值研究  

2-D numerical investigation on the influence of the column diameter ratio on the vortex-induced motion of the four-column platform

作　　者：陈元鑫 寇雨丰[1,2] 林志良 刘明月[1,2] CHEN Yuanxin;KOU Yufeng;LIN Zhiliang;LIU Mingyue(State Key Laboratory of Ocean Engineering, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240, China)

机构地区：[1]上海交通大学船舶海洋与建筑工程学院海洋工程国家重点实验室,上海200240 [2]高新船舶与深海开发装备协同创新中心,上海200240

出　　处：《海洋工程》2021年第1期43-52,共10页The Ocean Engineering

基　　金：国家自然科学基金项目(51909158,51979162);国家重点研发计划项目(2018YFC0309700);工信部高技术船舶科研项目数值水池创新专项([2016]23)。

摘　　要：与单立柱平台(Spar)类似,四立柱平台在洋流作用下也容易发生涡激运动,对锚泊和立管系统的疲劳寿命产生不利影响。一种非对称半潜式平台具有两种不同尺寸的立柱,立柱直径比对非对称平台涡激运动性能的影响尚需深入研究。采用计算流体力学(CFD)方法,对直径比分别为1.0、1.5和2.0的立柱组合在两种不同角度水流作用下的运动响应进行了二维数值模拟,分析发现:立柱直径比不为1时四立柱平台也具有明显的涡激运动,其横荡运动具有显著的锁定现象;在广义折合速度定义下,与相同直径的四立柱平台相比,立柱直径比不为1时其横荡运动锁定区间变宽且滞后,横荡响应幅值的峰值具有明显差异;在所研究的直径比范围内,大直径立柱在上游时涡激运动响应比其在下游时更显著,且这种差异随着直径比变大而变大。Similar to single-column platform(Spar),four-column platform is also subjected to vortex-induced motion(VIM)under the influence of current,which has a negative impact on the fatigue life of mooring and riser systems.An asymmetric semi-submersible has four columns of two different diameters.The effect of the diameter ratio of the columns on the vortex-induced motion of the platform needs further studies.In this study,by applying the method of computational fluid dynamics(CFD),two-dimensional numerical simulation is carried out for three different column combinations with diameter ratios of 1,1.5 and 2 at two different incidence angles.It is found that when the diameter ratio of the columns is not 1,the four-column platform also has obvious vortex-induced motion,and the phenomenon of lock-in is quite notable in sway motion.Under the definition of generalized reduced velocity,when the diameter ratio is not 1,the lock-in range of sway motion becomes wider and lagged compared with the four-column platform with the same diameter,and the peak value of sway response amplitude is significantly different.What's more,within the range of diameter ratio studied,the response of VIM of larger diameter column in the upstream is more significant than that in the downstream,and the difference increases as the diameter ratio increases.

关 键 词：非对称平台 立柱直径比 涡激运动 横荡运动 四立柱平台 流向角 

分 类 号：P751[交通运输工程—港口、海岸及近海工程]