考虑雷诺相似的串联双立管涡激振动模拟研究
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摘要
针对物理模型试验的缺点提出一种同时满足重力相似准则和雷诺相似准则的模拟方法。基于此方法采用ANSYS/CFX对不同间距的串联双立管进行了圆柱绕流和涡激振动模拟研究,并从受力系数、涡街发放等角度对模拟结果加以分析。结果表明:在整个间距范围内,下游立管所受涡激升力、脉动拖曳力系数以及响应振幅均明显大于上游立管。当间距为6～12倍管径时,上下游立管两向受力系数及响应振幅比其他间距情况大了约一个数量级;当间距为12倍管径时,两立管的受力系数和响应振幅均最大。当间距小于等于4倍管径时,两立管间无明显涡街产生,下游立管后方涡街以2S模式发放;间距大于等于6倍管径时,上游立管后方涡街以2S模式发放,下游立管后方涡街为2P模式发放;总的来说,在雷诺数1.35×105工况下,以圆柱绕流模拟来代替涡激振动所得结果差距不大,以此作为工程设计依据是安全可靠的。
Aiming at the shortcomings of the physical model test, a simulation method was proposed. This method satisfied both the gravity similarity criterion and the Reynolds similarity criterion. Based on this method, the circular flow and vortex induced vibration of the tandem risers with different distances were simulated by ANSYS/CFX, and the simulation results were discussed from many different angles such as force coefficient and vortex distribution. The results showed that when the spacing was 6 ～12 times the diameter of the riser, the two direction force coefficient and the response amplitude of the upstream and downstream risers were about one order of magnitude larger than the other spacing. In the whole spacing range, the two direction force coefficient and response amplitude of the downstream riser were obviously larger than that of the upstream riser. The force coefficient and the response amplitude of the two risers reached the maximum when the spacing was 12 times the diameters of the riser. When the spacing was less than 4 times the diameter of the riser,no vortex shedding of the two risers could be observed obviously,and the vortex shedding of the down-stream riser's behind was distributed in 2 S mode. When the spacing was more than or equal 6 times the diameter of the riser, the vortex shedding of the upstream riser's behind was distributed in 2 S mode, and the vortex shedding of the downstream riser's behind was 2 P model. In general,It was a safe and reliable design basis to replace Vortex induced vibration with a circular flow simulation in a Reynolds number of 1.35×105 conditions.
Aiming at the shortcomings of the physical model test, a simulation method was proposed. This method satisfied both the gravity similarity criterion and the Reynolds similarity criterion. Based on this method, the circular flow and vortex induced vibration of the tandem risers with different distances were simulated by ANSYS/CFX, and the simulation results were discussed from many different angles such as force coefficient and vortex distribution. The results showed that when the spacing was 6 ～12 times the diameter of the riser, the two direction force coefficient and the response amplitude of the upstream and downstream risers were about one order of magnitude larger than the other spacing. In the whole spacing range, the two direction force coefficient and response amplitude of the downstream riser were obviously larger than that of the upstream riser. The force coefficient and the response amplitude of the two risers reached the maximum when the spacing was 12 times the diameters of the riser. When the spacing was less than 4 times the diameter of the riser,no vortex shedding of the two risers could be observed obviously,and the vortex shedding of the down-stream riser's behind was distributed in 2 S mode. When the spacing was more than or equal 6 times the diameter of the riser, the vortex shedding of the upstream riser's behind was distributed in 2 S mode, and the vortex shedding of the downstream riser's behind was 2 P model. In general,It was a safe and reliable design basis to replace Vortex induced vibration with a circular flow simulation in a Reynolds number of 1.35×105 conditions.
引文
[1]李清平.我国海洋深水油气开发面临的挑战[J].中国海上油气, 2006,18(2):130-133.
[2]竺艳蓉.海洋工程波浪力学[M].天津:天津大学出版社, 1991.
[3]廖俊,景思睿.高雷诺数下双圆柱绕流的数值模拟[J].水动力学研究与进展(A辑), 2001, 16(1):101-110.
[4] WILLIAMSON C H K, GOVARDHAN R. A brief review of recent result in vortex-induced vibration[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2008, 96(6/7):713-735.
[5] WILLIAMSON C H K, JAUVTIS N. 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.
[6] JAUVTIS N, WILLIAMSON C H K. Vortex-induced vibration of a cylinder with two degrees of freedom[J]. Journal of Fluids and Structures, 2003, 17(7):1 035-1 042.
[7] MORSE T L, WILLIAMSON C H K. The effect of Reynolds number on the critical mass phenomenon in vortex-induced vibration[J]. Physics of Fluids, 2009, 21(4):045105.
[8] WANG Enhao, XIAO Qing, ZHU Qiang, et al. The effect of spacing on the vortex-induced vibrations of two tandem flexible cylinders[J]. Physics of Fluids, 2017, 29(7):077103.
[9] ZHAO Ming. Flow induced vibration of two rigidly coupled circular cylinders in tandem and side-by-side arrangements at a low Reynolds number of 150[J]. Physics of Fluids, 2013, 25(12):355-381.
[10]郭晓玲,唐国强,刘名名,等.低雷诺数下串联双圆柱涡激振动机理的数值研究[J].振动与冲击, 2014, 33(4):60-69.
[11]张大可,赵西增,胡子俊,等.低雷诺数下串列双圆柱涡激振动的数值模拟[J].哈尔滨工程大学学报, 2018, 39(2):247-253.
[12]康庄,倪问池.考虑旋转自由度的涡激振动数值模拟研究[J].振动与冲击, 2018, 37(9):185-189.
[2]竺艳蓉.海洋工程波浪力学[M].天津:天津大学出版社, 1991.
[3]廖俊,景思睿.高雷诺数下双圆柱绕流的数值模拟[J].水动力学研究与进展(A辑), 2001, 16(1):101-110.
[4] WILLIAMSON C H K, GOVARDHAN R. A brief review of recent result in vortex-induced vibration[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2008, 96(6/7):713-735.
[5] WILLIAMSON C H K, JAUVTIS N. 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.
[6] JAUVTIS N, WILLIAMSON C H K. Vortex-induced vibration of a cylinder with two degrees of freedom[J]. Journal of Fluids and Structures, 2003, 17(7):1 035-1 042.
[7] MORSE T L, WILLIAMSON C H K. The effect of Reynolds number on the critical mass phenomenon in vortex-induced vibration[J]. Physics of Fluids, 2009, 21(4):045105.
[8] WANG Enhao, XIAO Qing, ZHU Qiang, et al. The effect of spacing on the vortex-induced vibrations of two tandem flexible cylinders[J]. Physics of Fluids, 2017, 29(7):077103.
[9] ZHAO Ming. Flow induced vibration of two rigidly coupled circular cylinders in tandem and side-by-side arrangements at a low Reynolds number of 150[J]. Physics of Fluids, 2013, 25(12):355-381.
[10]郭晓玲,唐国强,刘名名,等.低雷诺数下串联双圆柱涡激振动机理的数值研究[J].振动与冲击, 2014, 33(4):60-69.
[11]张大可,赵西增,胡子俊,等.低雷诺数下串列双圆柱涡激振动的数值模拟[J].哈尔滨工程大学学报, 2018, 39(2):247-253.
[12]康庄,倪问池.考虑旋转自由度的涡激振动数值模拟研究[J].振动与冲击, 2018, 37(9):185-189.