Freely Vibrating Two Side-by-Side Square Columns With Combined Translational Motions
Freely Vibrating Two Side-by-Side Square Columns With Combined Translational Motions
复制标题
通过组合平移运动自由振动两个并排方柱
DOI：
10.1115/omae2016-54517
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
T. Lim
中科院分区：
文献类型：
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作者：
M. Guan;R. Jaiman;C. Kang;T. Lim
本文提出了一组对并排配置的两个相同方柱后面的流致振动 (FIV) 和耦合尾流的数值模拟。为了观察四种状态作为不同间隙比的函数，首先将稳态条件下低雷诺数Re=ρfUDμf配置的计算结果与中等雷诺数的现有实验数据进行比较。接下来我们研究弹性安装方柱的配置，这些方柱可以在流向和横向方向上自由振荡。通过 Petrov-Galerkin 有限元方法和任意拉格朗日-欧拉技术进行模拟，以解释流体网格运动。静止并排配置的四种状态遵循在中等雷诺数下进行的实验数据的相同趋势，而每个状态的范围由于湍流尾流特性而不同。对于自由振动条件，所有模拟均在低雷诺数 (Re = 200)、质量比等于 10m*=Mmf 和 Ur ε [1,50] 范围内的减速速度（其中 Ur=UfND）和自由阻尼条件 ζ = C2KM = 0 下计算。振动条件下的四种状态作为间隙比的函数进行研究 g* = g/D，内柱表面之间的间距与柱直径的比率。系统分析了速度降低对力变化、振动幅度和涡度轮廓的影响，以了解四种状态下并排柱的基本 FIV 物理原理。最后，我们提出了中等雷诺数 Re = 20,000 下全半潜式模型的 FIV 研究，这可以被视为并排配置的应用。
This paper presents a set of numerical simulations of flow-induced vibrations (FIV) and coupled wake flow behind two identical square columns in a side-by-side configuration. To observe the four regimes as a function of different gap ratios, the computational results of the configuration at low Reynolds number Re=ρfUDμf in stationary condition are firstly compared with existing experimental data of moderate Reynolds number. We next investigate the configuration of elastically mounted square columns, which are free to oscillate in both streamwise and transverse directions. The simulations are performed by the Petrov-Galerkin finite-element method and Arbitrary Lagrangian-Eulerian technique to account for the fluid mesh motion. The four regimes of stationary side-by-side configuration follow the same trend of the experimental data conducted at moderate Reynolds number, while the ranges of each regime differ due to the turbulent wake properties. For the freely vibrating condition, all the simulations are computed at low Reynolds number (Re = 200), mass ratio equal to 10m*=Mmf and reduced velocity in the range of Ur ∈ [1,50] where Ur=UfND and in free-damping condition ζ = C2KM = 0. The four regimes in vibrating condition are investigated as a function of gap ratios g* = g/D, which is the ratio of spacing between the inner column surfaces to the diameter of the column. The effects of reduced velocity on the force variations, the vibration amplitudes and the vorticity contours are analyzed systematically to understand the underlying FIV physics of side-by-side columns in the four regimes. Finally, we present a FIV study of the full semi-submersible model at moderate Reynolds number Re = 20,000 which can be considered as the application of side-by-side configuration.