ABSTRACT In the present study, we assessed the capabilities of Eulerian-Eulerian CFD two-phase flow simulation with the homogeneous Multiple Size Group Model (MUSIG) and consideration of breakup and coalescence under three-dimensional flow conditions. We compared void fraction, bubble size and bubble velocity distributions against experimental data from vertical gas-disperse two-phase flow in a pipe with a flow obstruction. The simulation results generally agree well upstream the obstacle, where we have a typically developed pipe flow. Downstream of the obstacle void fraction is overpredicted while bubble velocity is underpredicted. The bubble size distribution has no clear trend. With higher liquid velocities, the deviations increase. As a conclusion, the simulation has difficulties to balance the gas fraction in the strong vortex in the shadow of the obstacle. Here further model improvement is needed.

中文翻译：

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垂直管道中障碍物周围气泡流的 CFD 模拟，重点是破裂和聚结建模

摘要 在本研究中，我们评估了欧拉-欧拉 CFD 两相流模拟的能力，使用均质多尺寸组模型 (MUSIG) 并考虑三维流动条件下的破裂和聚结。我们将空隙率、气泡大小和气泡速度分布与来自具有流动障碍的管道中的垂直气体分散两相流的实验数据进行了比较。模拟结果通常与障碍物上游一致，在那里我们有一个典型的管道流。下游的障碍空隙率被高估，而气泡速度被低估。气泡大小分布没有明显的趋势。液体速度越高，偏差越大。作为结论，模拟很难平衡障碍物阴影中强涡流中的气体分数。这里需要进一步的模型改进。