Nowadays, pipelines are often used in marine engineering to effectively transport oil and natural gas due to their good continuity and high efficiency. However, the unwanted dynamics of the pipelines caused by the interaction between the external environment and internal fluid pipelines may affect their normal operation and service life. In the paper, we present a fiber-reinforced composite pipeline transporting liquid-gas two-phase flow to reduce harmful vibrations and investigate the present system's nonlinear vortex-induced vibration (VIV). Using Hamilton's principle, one can attain the dynamic equations governing the VIV in a fiber-reinforced pipeline that transports a two-phase petroleum and natural gas flow. The Galerkin technique is applied to discrete the governing equations from partial differential equations into a set of ordinary differential equations, and the numerical solutions are received using the Runge-Kutta methodology. Moreover, the exactitude of the theoretical model is verified by comparing it with published experimental and finite element results. Numerical results reveal the influence of internal and external velocities on the post-buckling behavior of the pipe. Moreover, the natural frequencies and maximum response displacements are discovered to be related to the parameters of two-phase flow such as slip ratio and liquid-phase volume coefficient. Besides, research has found that the axial tension significantly impacts on the VIV response of pipes in the supercritical regime, which means the maximum response displacement of the pipeline can be controlled by changing the tension amplitude.

中文翻译：

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输送液气两相流的纤维增强复合管的非线性涡激振动分析


如今，管道由于其良好的连续性和高效率，经常用于海洋工程以有效运输石油和天然气。但是，外部环境与内部流体管道之间的相互作用引起的管道不必要的动态可能会影响其正常运行和使用寿命。在本文中，我们提出了一种纤维增强复合管道，用于输送液气两相流以减少有害振动，并研究了该系统的非线性涡旋诱导振动 （VIV）。使用汉密尔顿原理，可以获得在输送两相石油和天然气流的纤维增强管道中控制 VIV 的动力学方程。Galerkin 技术用于将控制方程从偏微分方程分解为一组常微分方程，并使用 Runge-Kutta 方法接收数值解。此外，通过与已发表的实验和有限元结果进行比较，验证了理论模型的准确性。数值结果揭示了内部和外部速度对管道后屈曲行为的影响。此外，发现固有频率和最大响应位移与两相流参数有关，例如滑移比和液相体积系数。此外，研究发现，在超临界状态下，轴向张力对管道的 VIV 响应有显著影响，这意味着可以通过改变张力幅值来控制管道的最大响应位移。