Abstract Two phase flow is of great interest in chemical and petroleum industries, and multiphase pipe flow models with closure relationships require experimental data for their development and validation. However, only little experimental information is available for slightly upward inclined pipes. Experimental investigations of single elongated bubble in marginally upwardly inclined pipes less than 10° have therefore been performed. Observations of the bubble drift velocity along the pipe has been highlighted. The drift velocity data presented here can contribute to improve knowledge of pipe inclination and viscosity dependency in drift velocity correlations. The new data on the bubble characteristics - shape, length, fraction and drift velocity may also provide useful information for the development and validation of numerical models. The measured drift velocity data have therefore been compared with some recently developed bubble velocity correlations.

中文翻译：

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10度以下向上倾斜管道中液体中单个细长气泡的实验研究

摘要 两相流在化工和石油工业中很受关注，具有闭合关系的多相管流模型需要实验数据进行开发和验证。然而，对于稍微向上倾斜的管道，只有很少的实验信息可用。因此，已经对小于 10° 的略微向上倾斜的管道中的单个细长气泡进行了实验研究。沿管道的气泡漂移速度的观测已被突出显示。此处提供的漂移速度数据有助于提高对漂移速度相关性中管道倾斜度和粘度依赖性的了解。关于气泡特征的新数据——形状、长度、分数和漂移速度也可为数值模型的开发和验证提供有用的信息。