控制杆对柔性圆柱涡激振动的抑制效果研究
|
摘要
涡激振动会造成海洋柔性柱状构件疲劳损伤,合理的抑制装置能够有效延长结构的使用寿命。控制杆是常见的涡激振动抑制装置,高雷诺数条件下,多根控制杆的排布方式对涡激振动抑制效果的影响有待进一步研究。文中通过设计室内模型实验,观测了高雷诺数条件下控制杆对柔性圆柱涡激振动抑制效果。圆柱模型的长径比为350,质量比为1.9,最高雷诺数可达16 000。研究结果表明:控制杆对柔性圆柱的涡激振动抑制效果显著,四根控制杆的抑制效果优于三根控制杆。
Vortex-induced vibrations(VIV) is a complicated flow-structure interaction phenomenon that may cause fatigue damage of flexible cylinder structures in ocean engineering. VIV suppression devices can effectively extend the fatigue life of marine structures. VIV of cylinders can be suppressed by control rods,but the effectiveness in high Re and the layout of multiple control rods need further studies. Experimental investigations were conducted to evaluate the VIV suppression of control rods and their layout for flexible cylinder models(length to diameter ratio is 350, mass ratio is 1.9, the highest Re can reach 16 000) in this paper. The results show that control rods play a major role in suppressing VIV of a flexible cylinder and the appearance of the higher harmonics, in addition, four control rods are more efficient than three ones.
Vortex-induced vibrations(VIV) is a complicated flow-structure interaction phenomenon that may cause fatigue damage of flexible cylinder structures in ocean engineering. VIV suppression devices can effectively extend the fatigue life of marine structures. VIV of cylinders can be suppressed by control rods,but the effectiveness in high Re and the layout of multiple control rods need further studies. Experimental investigations were conducted to evaluate the VIV suppression of control rods and their layout for flexible cylinder models(length to diameter ratio is 350, mass ratio is 1.9, the highest Re can reach 16 000) in this paper. The results show that control rods play a major role in suppressing VIV of a flexible cylinder and the appearance of the higher harmonics, in addition, four control rods are more efficient than three ones.
引文
[1]Owen J C,Szewczyk A A,Bearman P W.Suppressing Karman vortex shedding by use of sinuous circular cylinders[C].APS Division of Fluid Dynamics Meeting Abstracts,1999,1.
[2]Bearman P,Brankovic M.Experimental studies of passive control of vortex-induced vibration[J].European Journal of Mechanics-B/Fluids,2004,23(1):9-15.
[3]Allen D,Lee L,Henning D.Fairings versus helical strakes for suppression of vortex induced vibration:technical comparisons[C].Proceedings of the Offshore Technology Conference,2008.
[4]Assi G R S,Bearman P W,Kitney N,et al.Suppression of wake-induced vibration of tandem cylinders with free-to-rotate control plates[J].Journal of Fluids and Structures,2010,26(7):1045-1057.
[5]Trim A D,Braaten H,Lie H,et al.Experimental investigation of vortex-induced vibration of long marine risers[J].Journal of Fluids and Structures,2005,21(3):335-361.
[6]Gao Y,Fu S,Ren T,et al.VIV response of a long flexible riser fitted with strakes in uniform and linearly sheared currents[J].Applied Ocean Research,2015,52:102-114.
[7]Zdravkovich M M.Review and classification of various aerodynamic and hydrodynamic means for suppressing vortex shedding[J].Journal of Wind Engineering and Industrial Aerodynamics,1981,7(2):145-189.
[8]Vandiver J K,Swithenbank S,Jaiswal V,et al.The effectiveness of helical strakes in the suppression of high-modenumber VIV[C].Offshore Technology Conference,2006.
[9]Allen D W.Performance characteristics of short fairings[C].Offshore Technology Conference,2003.
[10]Akilli H,Sahin B,Tumen N F.Suppression of vortex shedding of circular cylinder in shallow water by a splitter plate[J].Flow Measurement and Instrumentation,2005,16(4):211-219.
[11]Tsutsui T,Igarashi T.Enhancement of heat transfer and reduction of drag of a circular cylinder(flow control using a small rod)[J].Transactions of the JSME,1996,62(597):1802O1809.(in Japanese)
[12]宋吉宁,吕林,张健侨,等.三根附属控制杆对海洋立管涡激振动抑制作用实验研究[J].海洋工程,2009,27(3):23-29.Song Jining,LüLin,Zhang Jianqiao,et al.Experimental investigation of suppression of vortex-induced vibration of marine risers by three control rods[J].Ocean Engineering,2009,27(3):23-29.
[13]Wu H,Sun D P,Lu L,et al.Experimental investigation on the suppression of vortex-induced vibration of long flexible riser by multiple control rods[J].Journal of Fluids and Structures,2012,30:115-132.
[14]Lie H,Kaasen K E.Modal analysis of measurements from a large-scale VIV model test of a riser in linearly sheared flow[J].Journal of Fluids and Structures,2006,22:557-575.
[15]Chaplin J R,Bearman P W,Huera Huarte F J,Pattenden R J.Laboratory measurements of vortex-induced vibrations of a vertical tension riser in a stepped current[J].Journal of Fluids and Structures,2005,21:3-24.
[16]吴浩.多根控制杆对细长柔性立管涡激振动抑制作用的实验及数值研究[D].大连:大连理工大学,2013.Wu Hao.Experimental and numerical studies on the suppression of vortex induced vibration of long flexible riser by multiple control rods[D].Dalian:Dalian University of Technology,2013.'
[2]Bearman P,Brankovic M.Experimental studies of passive control of vortex-induced vibration[J].European Journal of Mechanics-B/Fluids,2004,23(1):9-15.
[3]Allen D,Lee L,Henning D.Fairings versus helical strakes for suppression of vortex induced vibration:technical comparisons[C].Proceedings of the Offshore Technology Conference,2008.
[4]Assi G R S,Bearman P W,Kitney N,et al.Suppression of wake-induced vibration of tandem cylinders with free-to-rotate control plates[J].Journal of Fluids and Structures,2010,26(7):1045-1057.
[5]Trim A D,Braaten H,Lie H,et al.Experimental investigation of vortex-induced vibration of long marine risers[J].Journal of Fluids and Structures,2005,21(3):335-361.
[6]Gao Y,Fu S,Ren T,et al.VIV response of a long flexible riser fitted with strakes in uniform and linearly sheared currents[J].Applied Ocean Research,2015,52:102-114.
[7]Zdravkovich M M.Review and classification of various aerodynamic and hydrodynamic means for suppressing vortex shedding[J].Journal of Wind Engineering and Industrial Aerodynamics,1981,7(2):145-189.
[8]Vandiver J K,Swithenbank S,Jaiswal V,et al.The effectiveness of helical strakes in the suppression of high-modenumber VIV[C].Offshore Technology Conference,2006.
[9]Allen D W.Performance characteristics of short fairings[C].Offshore Technology Conference,2003.
[10]Akilli H,Sahin B,Tumen N F.Suppression of vortex shedding of circular cylinder in shallow water by a splitter plate[J].Flow Measurement and Instrumentation,2005,16(4):211-219.
[11]Tsutsui T,Igarashi T.Enhancement of heat transfer and reduction of drag of a circular cylinder(flow control using a small rod)[J].Transactions of the JSME,1996,62(597):1802O1809.(in Japanese)
[12]宋吉宁,吕林,张健侨,等.三根附属控制杆对海洋立管涡激振动抑制作用实验研究[J].海洋工程,2009,27(3):23-29.Song Jining,LüLin,Zhang Jianqiao,et al.Experimental investigation of suppression of vortex-induced vibration of marine risers by three control rods[J].Ocean Engineering,2009,27(3):23-29.
[13]Wu H,Sun D P,Lu L,et al.Experimental investigation on the suppression of vortex-induced vibration of long flexible riser by multiple control rods[J].Journal of Fluids and Structures,2012,30:115-132.
[14]Lie H,Kaasen K E.Modal analysis of measurements from a large-scale VIV model test of a riser in linearly sheared flow[J].Journal of Fluids and Structures,2006,22:557-575.
[15]Chaplin J R,Bearman P W,Huera Huarte F J,Pattenden R J.Laboratory measurements of vortex-induced vibrations of a vertical tension riser in a stepped current[J].Journal of Fluids and Structures,2005,21:3-24.
[16]吴浩.多根控制杆对细长柔性立管涡激振动抑制作用的实验及数值研究[D].大连:大连理工大学,2013.Wu Hao.Experimental and numerical studies on the suppression of vortex induced vibration of long flexible riser by multiple control rods[D].Dalian:Dalian University of Technology,2013.'