In this paper, based on studies of the fracture-flooding technology in a third-class reservoir, a mathematical model is established, conforming to the law of fracture initiation and propagation and the seepage mechanism of the surfactant-containing fracturing fluid. Third-class reservoir mathematical models are used to study the influence of fracture-flooding injection volume, displacement, reservoir permeability, effective thickness, remaining oil saturation, and other factors on the enhanced oil recovery effect in the fracture-flooding technology. The Sobol method is used to analyze the influence of various factors on the overall sensitivity of the enhanced oil recovery effect. The study shows that the cumulative oil increase is the major response variable for third-class reservoir fracture-flooding, the remaining oil saturation is the most sensitive factor, and the injection volume and effective thickness parameters are also sensitive. Thus, the oil-increasing effect of third-class reservoir fracture-flooding is mainly based on the remaining oil potential of the reservoir, expressed by the remaining oil saturation and effective thickness parameters, and the fracture range, defined by the fracturing fluid injection volume.

本文在对某三级油藏压裂驱技术研究的基础上，建立了符合裂缝起裂扩展规律和含表面活性剂压裂液渗流机理的数学模型。采用三级油藏数学模型，研究压裂注水量、驱油量、油藏渗透率、有效厚度、剩余油饱和度等因素对压裂技术提高采收率效果的影响。Sobol方法用于分析各种因素对提高采收率效果的整体敏感性的影响。研究表明，累积增油量是三级油藏裂缝驱的主要响应变量，剩余油饱和度是最敏感的因素，注入量和有效厚度参数也很敏感。因此，三级油藏裂缝驱的增油效果主要基于油藏剩余油潜力，以剩余油饱和度和有效厚度参数表示，裂缝范围由压裂液注入量定义。 .