Method for roughening relative permeability of polymer flooding from pore scale to core scale

Abstract

The invention discloses a method for roughening the relative permeability of a polymer flooding from a pore scale to a core scale. The method comprises the steps: dividing a heterogeneous core into multiple regions according to the pore size or porosity of a pore structure of the heterogeneous core and selecting a characterization unit of each region; according to the pore structure information ofthe characterization units, acquiring porosity and permeability of each characterization unit; forming an equivalent pore structure by using basic pore structures with different coordination numbers;simulating a polymer flooding process within the equivalent pore structure to obtain relative permeability of the equivalent pore structure; assigning the relative permeability of the effective porestructure with different regions in the heterogeneous core according to the proportion of the characterization units in the core and generating an equivalent core model; and carrying out multi-phase flow numerical simulation in the equivalent core model to solve an oil-water two-phase seepage equation and thus acquiring a relative permeability curve of the whole core. Therefore, the roughening ofthe relative permeability of the polymer flooding from a pore scale to a core scale is realized.

Description

technical field [0001] The invention relates to a method for coarsening the relative permeability of polymer flooding from the pore scale to the core scale, and belongs to the field of oil field chemical flooding. Background technique [0002] Relative permeability curves reflect the seepage and distribution of multiphase fluids in reservoir rocks, and are the basis of reservoir engineering and reservoir numerical simulation. At present, the technical means to obtain the relative permeability curve include indoor oil displacement experiment measurement and relative permeability coarsening method. [0003] The indoor oil displacement experiment measurement method, as the name suggests, is to obtain the relative permeability curve through the indoor core displacement experiment. The length of the core is usually several centimeters to tens of centimeters, which is time-consuming, laborious and costly, and is currently the most commonly used method. Polymer flooding is differe...

AI Technical Summary

Problems solved by technology

It can be seen that the current relative permeability coarsening method is only suitable for the acquisition of relatively macroscopic relative permeability above the core scale, and there is no relative permeability coarsening method from the microscopic pore scale to the core scale.

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