缝洞型油藏大尺度可视化水驱油物理模拟实验及机理

缝洞型碳酸盐岩油藏由于其缝洞组合关系的复杂性,使得储层流体的渗流规律有别于常规油藏。根据某油田奥陶系缝洞型碳酸盐岩的实际情况设计制作了大尺度可视化物理模型,并按照现场实际设计了二注三采的实验井网及注采方案,以应用物理模拟实验来研究缝洞型碳酸盐岩油藏的开发特征及油井生产规律。结合实验结果,利用J.Cruz-Hernández建立的数学模型对生产数据进行拟合,以研究缝洞型碳酸盐岩油藏中流体的渗流机理,J.Cruz-Hernández数学模型中的空间系数和流动速度对采收率影响较大,提出模型的改进应考虑重力分异作用、溶洞比例等影响因素。

Large-Scale Visible Water/Oil Displacing Physical Modeling Experiment and Mechanism Research of Fracture-Vuggy Reservoir

The complexity in the fracture-vuggy carbonate reservoir makes its flowing law of formation fluid different from that of the normal reservoir. In order to recognize the special flow mechanism deeply, this paper has designed and established a large-scale visible model based on the actual conditions of Ordovician fracture-vuggy carbonate oil rocks in a reservoir. The experimental well network and injection/production strategy were planned according to the present field area. Also physical model experiments were conducted to study the developing characteristics and well production law. In order to reveal the flowing law of the fractured-vuggy reservoir, the experimental data have been analyzed carefully and used in fitting J.Cruz-Hernández′s fracture-vuggy carbonate water/oil two-phase flow mathematical model based on convective diffuse filtration theory. In addition, several affecting factors of this model have been discussed such as the fraction of the porous space, the coefficient of transfer of fluids and flow velocity. In the end, the paper proposes that such factors as gravity, and coordinate number of vug should be included in the development of the model.