当前双自由度涡激振动数值模拟的研究模拟结果精度并不十分理想，尤其是对于最大振幅的响应的估计。在Jauvtis & Williamson的实验中，观测到低质量比圆柱的最大振幅可达1.5D，并将其命名为“超上端分支”。然而，当前研究很少有模拟结果能达到1.3D，甚至无法捕捉到超上端分支，其原因很可能是湍流模型本身的缺陷以及数值模拟参数设置的不合理。针对上述问题，本文基于开源软件OpenFOAM，采用了改进的k-ε湍流模型，研究了加速度对涡激振动响应的影响，优化了数值模拟方法。通过振幅、相位、轨迹、尾涡等响应的分析，证明在适当的加速度下，运用改进k-ε模型可对双自由度涡激振动实现较精确的数值模拟。
Abstract
The existing simulation results for 2-DOF vortex-induced vibration are not satisfied, especially, the maximum amplitude estimation of its responses. In tests of Jauvtis & Williamson, the maximum amplitude of a cylinder with a low mass ratio could reach 1.5D, this phenomenon was named “super upper branch”. But, few simulation results of current studies can reach 1.3D even unable to capture super upper branch. The reasons were likely to be defects of the turbulence model itself and the unreasonable setting of numerical simulation parameters. Aiming at the problems mentioned above, an improved k-ε turbulence model was used to study the effect of acceleration on responses of vortex-induced vibration here based on the software OpenFOAM and optimize the numerical simulation method. By analyzing responses of amplitude, phase, trajectory and tail vortex, it was shown that 2-DOF vortex-induced vibration can be numerically simulated more accurately with the improved k-ε turbulence model under appropriate accelerations.
关键词
涡激振动；k-&epsilon /
湍流模型；加速度；数值模拟
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Key words
vortex-induced vibration (VIV) /
k-&epsilon /
turbulence model /
acceleration /
numerical simulation
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参考文献
[1] 范杰利, 黄维平. 细长立管两向自由度涡激振动数值研究[J]. 振动与冲击, 2012, 31(24):65-68.
Fan J L, Huang W P. Numerical simulation of 2-DOF vortex-induced vibration of a long riser[J]. Zhendong Yu Chongji/journal of Vibration & Shock, 2012, 31(24):65-47.
[2] Jauvtis N, Williamson C. H. K. The effect of two degrees of freedom on vortex-induced vibration at low mass and damping[J]. Journal of Fluid Mechanics, 2004, 509(509):23-62.
[3] Williamson C. A high-amplitude 2T mode of vortex-induced vibration for a light body in XY motion[J]. European Journal of Mechanics - B/Fluids, 2004, 23(1):107-114.
[4] Pan Z Y, Cui W C, Miao Q M. Numerical simulation of vortex-induced vibration of a circular cylinder at low mass-damping using RANS code[J]. Journal of Fluids & Structures, 2007, 23(1):23-37.
[5] Sanchis A, Sælevik G, Grue J. Two-degree-of-freedom vortex-induced vibrations of a spring-mounted rigid cylinder with low mass ratio[J]. Journal of Fluids & Structures, 2008, 24(6):907-919.
[6] 谷家扬, 杨建民, 肖龙飞. 两种典型立柱截面涡激运动的分析研究[J]. 船舶力学, 2014(10):1184-1194.
Gu, J Y, YANG J M and XIAO L F. Study on vortex induced motion of two typical different cross-section columns [J]. Journal of Ship Mechanics, 2014(10):1184-1194.
[7] 林琳, 王言英. 不同湍流模型下圆柱涡激振动的计算比较[J]. 船舶力学, 2013(10):1115-1125.
Lin L, Wang Y Y. Comparison between different turbulence models on vortex induced vibration of circular cylinder[J]. Chuan Bo LI Xue/journal of Ship Mechanics, 2013, 17(10):1115-1125.
[8] Srinil N, Zanganeh H, Day A. Two-degree-of-freedom VIV of circular cylinder with variable natural frequency ratio: Experimental and numerical investigations[J]. Ocean Engineering, 2013, 73(8):179-194.
[9] Medic G. Etude mathématique des modèles aux tensions de Reynolds et simulation numérique d'écoulements turbulents sur parois fixes et mobiles[J]. Bibliogr, 1999.
[10] Younis B A, Przulj V P. Computation of turbulent vortex shedding[J]. Computational Mechanics, 2006, 37(5):408-425.
[11] Guilmineau E, Queutey P. Numerical simulation of vortex-induced vibration of a circular cylinder with low mass-damping in a turbulent flow[J]. Journal of Fluids & Structures, 2004, 19(4):449-466.
[12] Durão D F G, Heitor M V, Pereira J C F. Measurements of turbulent and periodic flows around a square cross-section cylinder [J]. Experiments in Fluids, 1988, 6(5):298-304.
[13] Jung Y W, Park S O. Vortex-shedding characteristics in the wake of an oscillating airfoil at low Reynolds number [J]. Journal of Fluids & Structures, 2005, 20(3):451-464.
[14] Cant S. S. B. Pope, Turbulent Flows, Cambridge University Press, Cambridge, U.K. 2000, 771 pp.[J]. Combustion & Flame, 2001, 125(4):1361-136
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