Method for simulating fractional multi-phase/multi-component flow through porous media

摘要

A method for computing or estimating fractional, multi-phase/multi-component flow through a porous medium employing a 3D digital representation of a porous medium and a computational fluid dynamics method to calculate flow rates, pressures, saturations, internal velocity vectors and other flow parameters is described. The method employs a unique method of introducing non-wetting and wetting fluids into the pores at the inlet face of the 3D digital representation of a porous medium and a novel process control application to achieve quasi-steady state flow at low inlet concentrations of non-wetting fluid. In addition, the method of the present invention reduces the time required to simulate to complete the fluid dynamic calculations. The resulting values of flow of non-wetting fluid, wetting fluid, saturation, and other parameters are used to generate plots of relative permeability imbibition and drainage curves. Computerized systems and programs for performing the method are also provided.

主权项

1. A method for simulating fractional flow of wetting fluids and non-wetting fluids through porous medium comprising the steps of:
a) creating a three dimensional digital representation of a physical sample of a porous medium (Sample) containing a total volume of fluids comprising wetting fluids and non-wetting fluids, wherein the creating comprises scanning the Sample with a device producing a three-dimensional (3D) digital representation of porous structure of the Sample, b) defining a first fraction of the total volume of fluids that comprises the wetting fluids and a second fraction of the total volume of fluids that comprises the non-wetting fluids, c) defining a value for a flow rate of the total volume of fluids flowing through the Sample, d) assessing properties of the wetting fluids and the non-wetting fluids, e) defining initial conditions for saturation of the wetting fluids (Sw), saturation of the non-wetting fluids (Sn), inlet pressure of the wetting fluids (Pw) and inlet pressure of the non-wetting fluids (Pn), f) setting conditions at the inlet face of the Sample wherein non-wetting fluids and wetting fluids enter the pores of the Sample in separate and distinct areas, and g) calculating pressures, saturation, and velocity vectors internal to the Sample, h) calculating flow rates of the non-wetting fluids (Qn) through the Sample, flow rates of the wetting fluids (Qw) through the Sample, and pressure at the outlet of the Sample, i) repeating steps a) through h) for a predefined number of time increments, t, and j) periodically adjusting the inlet pressures Pn and Pw using a feedback control algorithm wherein quasi-steady state values for Qn and Qw are achieved.