Geometric arrangements known as flow patterns are typically observed when there are multiple immiscible fluids flowing through any control volume. The adequate modelling of the flow characteristic is important, especially in applications where flow visualization is not possible due to field constrains, like, for instance, in oil production. Intermittent slug flow occurs frequently in petroleum production systems and there is a lack of understanding of its characteristics in inclined annular geometries. Even though this is a frequent geometry encountered in the production system, there is lack of in-depth experimental studies about it. Moreover, existing models for calculating the slug frequency in vertical annular duct cannot predict the slug frequency in inclined annular duct. In this work, a dedicated experimental apparatus equipped with flow meters and a high-speed camera was built in order to investigate some characteristics of the slug flow in slightly inclined annulus, mainly the drift-flux parameters and the frequency of the slug. It is shown that modified drift-flux models for vertical annular flow can be used to calculate drift-flux parameters in inclined annular flow. In addition, a new model is proposed for calculating the slug frequency with improved accuracy when compared to the models available in the literature. The proposed model is suitable for industrial applications in the design of equipment in which such duct geometry is present.

当有多种不混溶的流体流过任何控制体积时，通常会观察到称为流型的几何排列。流动特性的适当建模非常重要，尤其是在由于田间约束而无法进行流动可视化的应用中，例如在石油生产中。间歇塞流在石油生产系统中经常发生，并且缺乏对其在倾斜环形几何形状中的特性的了解。即使这是生产系统中经常遇到的几何图形，也缺乏对其进行深入的实验研究。而且，现有的用于计算垂直环形管道中的塞子频率的模型不能预测倾斜环形管道中的塞子频率。在这项工作中 为了研究在略微倾斜的环空中的团状流的一些特征，主要是漂移通量参数和团状频率，建立了一个配备有流量计和高速照相机的专用实验设备。结果表明，改进的垂直环流漂移通量模型可用于计算倾斜环流中的漂移通量参数。此外，与文献中可用的模型相比，提出了一种新模型，用于以更高的精度计算弹头频率。提出的模型适用于工业设计中存在这种管道几何形状的设备。主要是漂移通量参数和弹头的频率。结果表明，改进的垂直环流漂移通量模型可用于计算倾斜环流中的漂移通量参数。此外，与文献中可用的模型相比，提出了一种新模型，用于以更高的精度计算弹头频率。提出的模型适用于工业设计中存在这种管道几何形状的设备。主要是漂移通量参数和弹头的频率。结果表明，改进的垂直环流漂移通量模型可用于计算倾斜环流中的漂移通量参数。此外，与文献中可用的模型相比，提出了一种新模型，用于以更高的精度计算弹头频率。提出的模型适用于工业设计中存在这种管道几何形状的设备。