The development of oil and gas resources is gradually transferring to the deep sea, and the hydrate plugging of submarine pipelines at high pressures and low temperatures is becoming an important problem to ensure the safety of pipeline operations. The swirl flow is a new method to expand the boundary of hydrate safe flow. Numerical simulation of the hydrate slurry flow characteristics in a horizontal pipeline by twisted band has been carried out, and the flow of CO₂ hydrate slurry in low concentration has been simulated by the RSM and DPM models. The results show that the heat transfer efficiency is also related to Re and particle concentration. The velocity distribution has the form of symmetrical double peaks, and the peaks finally merge at the center of the pipeline. Vortexes firstly appear on both sides of the edge of the twisted band, and then move to the middle part of the twisted band. Finally, the vortex center almost coincides with the velocity center. The rotation direction of hydrate particles is the same as the twisted direction of the twisted band, twist rate (Y) is smaller, Re is larger, and the symmetric vortex lines merge farther away. The initial swirl number is mainly related to Y, but not Re. The swirl flow attenuates exponentially, and its attenuation rate is mainly related to Re, but not Y. Compared with ordinary pipelines, the swirl flow can obviously improve the transportation distance of hydrate slurry.

中文翻译：

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CO2水合物浆液旋流特性的短扭带数值模拟

油气资源开发逐步向深海转移，高压低温海底管道水合物堵塞成为保障管道运行安全的重要问题。旋流是一种拓展水合物安全流动边界的新方法。通过扭带对水平管道中水合物浆液流动特性进行了数值模拟，CO ₂的流动RSM 和 DPM 模型模拟了低浓度的水合物浆液。结果表明，传热效率还与Re和颗粒浓度有关。速度分布呈对称的双峰形式，峰最终在管道中心汇合。涡流首先出现在扭曲带边缘的两侧，然后移动到扭曲带的中间部分。最后，涡流中心几乎与速度中心重合。水合物粒子的旋转方向与扭曲带的扭曲方向相同，扭曲率(Y)较小，Re较大，对称涡线汇合较远。初始旋流数主要与 Y 相关，与 Re 无关。涡流呈指数衰减，其衰减率主要与Re有关，