Parameter Effect Analysis of Non-Darcy Flow and a Method for Choosing a Fluid Flow Equation in Fractured Karstic Carbonate Reservoirs

Fractured karstic carbonate reservoirs have obvious multi-scale characteristics and severe heterogeneity due to the development of abundant karst caves fractures with different scales. Darcy non-Darcy flows coexist this property. Therefore, selecting appropriate flow equations for regions in numerical simulation fluid flows, particularly two-phase multiphase is a critical topic. This paper compares analyses displacement distance differences waterfront travel using Darcy, Forchheimer Barree–Conway equations, as well analyzes influence constant, viscosity, rate absolute permeability on inertia action based Buckley–Leverett theory. The results show that number/Reynolds number water/oil not constant value varies water saturation, making it difficult determine whether inertial should be considered solely these values; can measured by comparing difference between distances waterflood front, quantitative standard given selection equation calculating allowable error front. magnitude effect affected physical properties reservoir medium velocity. smaller viscosity oil/water fluid, is. technique was used preliminary attempt analyze fractured at Tarim, confirmed validity method described article.