海底悬跨输流管道纯顺流向涡激振动特性研究

摘要

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。%An effective wake oscillator model for pure in-line (IL) vortex induced-vibrations (VIV) of a free spanning pipeline conveying fluid was presented. Two different kinds of van der Pol equa-tions were adopted to describe the wake dynamics related to the fluctuating nature of symmetric vor-tex shedding in the first IL VIV region and alternate vortex shedding in the second one. The effects of span length, internal fluid and axial tension on the pure IL VIV dynamics were mainly investigat-ed. The results indicate that long span length, small axial tension and high internal fluid velocity could reduce the incident current velocity range of pure IL VIV and make pure IL VIV easy to occur.