Dynamic Network Modeling of Resistivity Index in a Steady-State Procedure

Abstract

We present numerical results of electrical resistivity of two-phase flow in reservoir rocks using a dynamic network model. The model accounts for viscous and capillary forces, as well as wetting layers in the crevices of the pore space. It can be used as a unified model for drainage, imbibition and steady-state displacement. We use the model to study viscous effects on electrical resistivity for two-phase flow under strongly water-wet conditions. The pore network is extracted from a realistic pore space of a sandstone. For unsteady drainage and imbibition, our numerical results display capillary number dependent non-Archie behavior and hysteresis of the resistivity index. For steady-state displacement the resistivity index exhibits no significant hysteresis. For increasing capillary number we observe a higher degree of non-Archie (negative curvature) behavior. The simulated data are compared with relevant experimental data, and are in good agreement. Our conclusion is that the dynamic network model successfully reproduces viscous effects on the resistivity index in drainage, imbibition and steady-state displacement processes.

Characterization of CO2 miscible/immiscible flooding in low-permeability sandstones using NMR technology and VOF method

“…Core numerical simulation has unique advantages in comparation. At present, digital cores numerical simulation mainly includes pore network simulation methods [15][16][17] , LBM methods [18] , and Navier Stokes methods. Compared to the pore network simulation method, the Navier Stokes simulation method extracts the real pore throat based on digital rock cores, establishes a pore throat mesh model, and directly solves the Navier Stokes equation.…”