Abstract Slug flow is an intermittent and complex gas-liquid flow pattern, that can cause severe problems in industrial operations and lead to large uncertainties in multiphase flow metering. These problems are primarily caused by the liquid slugs of the flow. In this context, different cases of slug flow in horizontal pipes are investigated to find a statistical characterization of the slugs in time and space. To achieve this, snapshot proper orthogonal decomposition (snapshot POD) with an additional mode coupling algorithm is employed, which provides an energy-ranked mode basis of the underlying coherent structures. It is shown that the characterization for the considered slug flows can be derived from the temporal and spatial information of the dominant mode pair. In that regard, the slug frequencies, the averaged slug body length and an energy representation of the slugs are obtained from this method. Furthermore, the accuracy of this characterization is shown and the influence of the size of the observed pipe section on its reliability is investigated.

中文翻译：

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使用快照正确正交分解的水平段塞流的统计表征

摘要 段塞流是一种间歇性复杂的气液流动模式，会给工业操作带来严重的问题，并导致多相流量计量存在较大的不确定性。这些问题主要是由流动的液体段塞引起的。在这种情况下，研究了水平管道中段塞流的不同情况，以找到段塞在时间和空间上的统计特征。为了实现这一点，采用了带有附加模式耦合算法的快照适当正交分解（快照 POD），它提供了底层相干结构的能量排序模式基础。结果表明，所考虑的段塞流的特征可以从主要模式对的时间和空间信息中推导出来。在这方面，段塞频率，平均段塞体长度和段塞的能量表示是从该方法获得的。此外，还显示了这种表征的准确性，并研究了观察到的管段尺寸对其可靠性的影响。