考虑界面张力和液滴变形影响的携液临界流量模型

现有的携液临界流量模型通常认为界面张力及曳力系数为常数，忽略温度及压力对界面张力、液滴尺寸及液滴变形对曳力系数的影响，造成预测携液临界流量的结果与实际结果有较大差异。为了更准确预测气井携液临界流量，首先通过分段拟合界面张力实验数据，建立界面张力公式，然后引入变形液滴曳力系数公式及液滴变形程度和液滴尺寸之间的关系式，得到考虑界面张力和液滴变形影响的携液临界流量模型。研究结果表明，温度越高，压力越大，界面张力越小，携液临界流量越小；液滴尺寸越大，液滴变形越严重，液滴高宽比越小，曳力系数越大，携液临界流量越小。实验表明，模型预测数据与气井微观液滴积液实验数据基本吻合一致，其准确度远远高于Turner模型和李闽模型。新模型能够更加准确预测不同液滴尺寸下的携液临界流量，符合气田开发规律，为油气田开发提供技术指导。

Critical liquid carrying flow rate model with consideration of interfacial tension and droplet deformation effect

At present, the interfacial tension and drag coefficient are usually considered as the constants by the critical liquid carrying flow rate model, and the effect of temperature and pressure on the interfacial tension and the influence of droplet size and deformation on drag coefficient both are neglected.Thus, the prediction of critical liquid carrying flow rate has great difference from the actual results.In order to predict the critical liquid carrying flow rate of the gas wells more accurately, first, the interfacial tension formula was established by segmental fitting the experimental data of the interfacial tension; then, the critical liquid carrying flow model with consideration of the effect of the interfacial tension and droplet deformation was obtained by introducing the deformable droplet drag coefficient formula and the relationship formula between the droplet deformation degree and the droplet size.The research results show that the higher the temperature and the pressure are, the smaller the interfacial tension and critical liquid carrying flow rate are.Besides, the bigger the droplet size is and the more serious the droplet deformation is, the smaller the height-width ratio is, the bigger the drag coefficient is and the smaller the critical liquid carrying flow rate is.The experimental results indicate that the model can agree well with the experimental data of microscopic droplet effusions of the gas wells.Moreover, the new model can predict the critical liquid carrying flow rate with different droplet sizes more accurately and be more suitable to the development rules of the gas fields.