水平井井筒气两相流动规律及积液特征研究

Study on the Two-Phase Flow Patterns and Liquid Loading Characteristics in Horizontal Wellbore Gas

摘要: 由于气田开发中出水气井所占比例逐年增加，明确水平井井筒气两相流动规律及积液特征对于解决气井出水问题具有重要意义。然而，水平气井出水特征规律复杂、无法准确预测积液风险，导致水平井井筒气两相流动规律及积液特征尚不清楚。因此，从水平气井气水两相流动规律研究入手，通过建立水平井气水两相渗管耦合流动模型，我们可以对水平井复杂完井段的积液过程进行深入的数值模拟分析。并在总结前人成果的基础上，深入探讨了水平气井的气水两相流动规律，同时研究了积液过程的携液模型和积液模型。研究结果表明，水平井筒内的气两相流动有多种流型，有分层流、间歇流、环雾流等。这些流型受多种因素影响，如管径，倾角，流体性质等。特别是影响空气和水流类型最显著的是管径和倾斜度。积液过程受到各种因素的影响，如气量、水量、轨迹上的倾角以及轨迹的起伏程度等。

Abstract: As the proportion of water-producing gas wells in gas field development increases year by year, clarifying the gas two-phase flow pattern and liquid accumulation characteristics in horizontal wellbores is of great significance for addressing the issue of water production in gas wells. However, due to the complex and unpredictable nature of water production characteristics in horizontal gas wells, which makes it difficult to accurately predict the risk of liquid accumulation, the gas two-phase flow pattern and liquid accumulation characteristics in horizontal wellbores remain unclear. Therefore, starting from studying the gas-water two-phase flow pattern in horizontal gas wells, by establishing a coupled flow model for gas-water two-phase percolation in horizontal wells, we can conduct in-depth numerical simulation analysis of the liquid accumulation process in the complex completion section of horizontal wells. Based on a summary of previous research, this study delves into the gas-water two-phase flow pattern in horizontal gas wells, while also examining the liquid carrying and accumulation models in the liquid accumulation process. The results show that there are multiple flow patterns of gas two-phase flow in horizontal wellbores, including stratified flow, intermittent flow, annular-mist flow, etc. These flow patterns are influenced by various factors such as pipe diameter, inclination, and fluid properties. Among them, pipe diameter and inclination have the most significant impact on the gas-water flow patterns. The liquid accumulation process is influenced by various factors, including gas volume, water volume, inclination angle along the trajectory, and the degree of fluctuation in the trajectory.