文章提出了海底悬空输流管道纯顺流向涡激振动预报的尾流振子模型,运用两类不同的van der Pol方程描述旋涡尾迹特性。重点分析了悬跨长度,内流因素和轴向力对纯顺流向涡激振动的影响。结果表明:大悬跨长度、小轴向力和高速内流介质可以...文章提出了海底悬空输流管道纯顺流向涡激振动预报的尾流振子模型,运用两类不同的van der Pol方程描述旋涡尾迹特性。重点分析了悬跨长度,内流因素和轴向力对纯顺流向涡激振动的影响。结果表明:大悬跨长度、小轴向力和高速内流介质可以降低纯顺流向涡激振动发生的速度范围,使其更容易发生。展开更多
在实际工程中圆柱结构顺流向的涡激振动比较常见,其对结构的疲劳破坏影响也十分显著。该文分析了弹性支承圆柱在顺流向第一不稳定区内的涡激振动,运用Van der Pol方程描述对称旋涡脱落的尾迹特性,采用尾流振子模型计算结构响应,并研究...在实际工程中圆柱结构顺流向的涡激振动比较常见,其对结构的疲劳破坏影响也十分显著。该文分析了弹性支承圆柱在顺流向第一不稳定区内的涡激振动,运用Van der Pol方程描述对称旋涡脱落的尾迹特性,采用尾流振子模型计算结构响应,并研究了质量-阻尼参数和质量率对顺流向涡激振动的影响机理。数值计算结果表明,在第一不稳定区内,弹性支承圆柱顺流向涡激振动存在临界质量率。展开更多
With the development of the offshore deep water oil industry many researchers are focusing on the vortex-induced vibrations （VIV） of deep risers. In the present work, Reynolds-averaged Navier-Stokes （RANS） equatio...With the development of the offshore deep water oil industry many researchers are focusing on the vortex-induced vibrations （VIV） of deep risers. In the present work, Reynolds-averaged Navier-Stokes （RANS） equations were combined with the SST κ-ω turbulent model to simulate the stream-wise and transverse motion of an elastically mounted cylinder with a low mass-ratio, a natural frequency ratio of fx/fy = 1 and an Re number between 5 300 and 32 000, The four-order Runge-Kutta method was applied to solve the oscillating equation of the cylinder. The relationship between reduced velocity and parameters of the cylinder, including the lift coefficient, the drag coefficient, displacement and the vortex structure were then compared with recent experimental results and discussed in detail. The present numerical simulation reproduced effects have been observed in experiments, such as the lock-in phenomenon, the hysteretic phenomenon and beating behavior.展开更多
基金Supported by China Postdoctoral Science Foundation funded project(2013M530116)the National Natural Science Foundation of China(Nos.51209161,51239008 and 51379144)the Major State Basic Research Development Program of China(973 Program)(No.2014CB046803)
文摘文章提出了海底悬空输流管道纯顺流向涡激振动预报的尾流振子模型,运用两类不同的van der Pol方程描述旋涡尾迹特性。重点分析了悬跨长度,内流因素和轴向力对纯顺流向涡激振动的影响。结果表明:大悬跨长度、小轴向力和高速内流介质可以降低纯顺流向涡激振动发生的速度范围,使其更容易发生。
基金grants from the Specialized Research Fund for the Doctoral Program of Higher Education of China (SRFDP) (20100032120047)Independent Innovation Fund of Tianjin University (2010XJ-0098)State Key Laboratory of Ocean Engineering (Shanghai Jiao Tong University) (Grant No.1104)
文摘文章研究了刚性支承圆柱的顺流向涡激振动特性,在第二激励区域,运用van der Pol方程描述漩涡脱落的尾迹特性,采用尾流振子模型计算圆柱结构的响应,讨论和分析了质量-阻尼参数、质量率和结构阻尼对顺流向涡激振动的影响机理。
文摘在实际工程中圆柱结构顺流向的涡激振动比较常见,其对结构的疲劳破坏影响也十分显著。该文分析了弹性支承圆柱在顺流向第一不稳定区内的涡激振动,运用Van der Pol方程描述对称旋涡脱落的尾迹特性,采用尾流振子模型计算结构响应,并研究了质量-阻尼参数和质量率对顺流向涡激振动的影响机理。数值计算结果表明,在第一不稳定区内,弹性支承圆柱顺流向涡激振动存在临界质量率。
文摘With the development of the offshore deep water oil industry many researchers are focusing on the vortex-induced vibrations （VIV） of deep risers. In the present work, Reynolds-averaged Navier-Stokes （RANS） equations were combined with the SST κ-ω turbulent model to simulate the stream-wise and transverse motion of an elastically mounted cylinder with a low mass-ratio, a natural frequency ratio of fx/fy = 1 and an Re number between 5 300 and 32 000, The four-order Runge-Kutta method was applied to solve the oscillating equation of the cylinder. The relationship between reduced velocity and parameters of the cylinder, including the lift coefficient, the drag coefficient, displacement and the vortex structure were then compared with recent experimental results and discussed in detail. The present numerical simulation reproduced effects have been observed in experiments, such as the lock-in phenomenon, the hysteretic phenomenon and beating behavior.
