Reliable and accurate prediction of the transition from spherical cap bubble to slug flow is crucial not only to the operation of industrial facilities such as the crude oil pipelines, bubble column, and nuclear reactors but also for model development for computational fluid dynamics (CFD) studies. The present paper presents a review of the transition mechanics from spherical cap bubble flow to slug flow in vertical pipes. The bubble flow was split into sub-regions, bubbles and spherical cap bubbles and the mechanisms to classify them (i.e., bubble terminal velocity and cap bubble velocity) was analysed. For now, the literature review does not present some important previous works. This paper presents an original data set of gas–silicone oil in vertical pipes to support the new findings. The experimental two-phase data classifies the flow patterns using the probability density function (PDF) and shows the important flow variables such as average void fraction, pressure gradient, slug body void fraction, liquid slug, Taylor bubble and slug unit lengths, structural velocity and frequency obtained by electrical capacitance tomography (ECT) and a wire mesh sensor (WMS).

可靠，准确地预测从球形帽气泡到团状流的过渡过程，不仅对诸如原油管道，气泡塔和核反应堆等工业设施的运行至关重要，而且对于计算流体动力学（CFD）研究的模型开发也至关重要。 。本文介绍了垂直管道中从球形帽气泡流到团状流的过渡力学。将气泡流分为多个子区域，气泡和球形帽状气泡，并分析了将气泡分类的机制（即气泡末端速度和帽状气泡速度）。目前，文献综述并未介绍一些重要的先前著作。本文介绍了垂直管道中的气体-硅油的原始数据集，以支持新的发现。