Numerical simulation and sensitivity evaluation of fracture-flooding in Class III reservoir

Abstract

Based on the third-class reservoir of fracture-flooding technology, a mathematical model that
conforms to the law of fracture initiation and propagation of fracture-flooding and the seepage mechanism
of fracturing fluid (surfactant) is established. The third-class reservoir of fracture-flooding 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. 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 response variable for
the third-class reservoir fracture-flooding, the remaining oil saturation is the most sensitive, and the injection
volume and effective thickness are sensitive. Second. The oil-increasing effect of the third-class reservoir
fracture-flooding is mainly based on the remaining oil potential of the reservoir (remaining oil saturation,
effective thickness) and fracture range (fracturing fluid injection volume).