A Meshing Method for Inclined Fractures Based on Embedded Discrete Fracture Model

Abstract

The invention provides an inclined fracture mesh generation method based on an embedded discrete fracture model, which belongs to the technical field of oil reservoir simulation and comprises the following steps of: establishing a matrix mesh system, acquiring a fracture surface boundary and a projection surface of the matrix mesh system on each coordinate axis plane, inverting the projection of the matrix mesh penetrated by the fracture surface on each projection surface to obtain a matrix mesh penetrated by the fracture surface, dividing a fracture surface by using the boundary of the matrixmesh to obtain a preliminary fracture mesh, and taking the fracture surface boundary as a constraint condition, initially retaining the part of the initial fracture mesh within the fracture boundaryand obtaining the final fracture mesh. According to the method, the embedded discrete fracture model is used for generating any polygonal fracture surface in the stratum, particularly, the inclined fracture meshes can be generated, and the seepage law in the stratum with complex fracture distribution can be studied.

Description

technical field [0001] The invention belongs to the field of oil reservoir simulation technology, in particular, relates to a grid subdivision method for inclined fractures based on an embedded discrete fracture model. Background technique [0002] With the development of conventional oil and gas resources, conventional reservoirs with high porosity and high permeability have been exhausted. In order to meet the increasing demands of oil and natural gas resources, it is imperative to develop unconventional low-permeability reservoirs. Field practice shows that low-permeability tight reservoirs are characterized by low permeability, so fracturing horizontal well technology is usually used. Because conventional reservoir engineering methods are difficult to deal with complex fractured reservoir seepage, numerical simulation methods are often used to study it. In the reservoir numerical simulation method, the embedded discrete fracture model does not need to refine the grid, ...

AI Technical Summary

Problems solved by technology

However, in the embedded discrete fracture model, the fracture grid is obtained by subdividing the structured matrix grid boundary, while in the 3D model, the intersection pattern between the fracture plane and the matrix grid is very complicated, so it is very difficult to subdivide the inclined fracture grid , most scholars still use the simplified model of the vertical fracture model, but this simplified model is quite different from the actual situation, so the simulation results cannot reflect the real formation situation

The purpose of the present invention is to propose a grid subdivision method for inclined fractures based on an embedded discrete fracture model, and to solve the current research situation that it is difficult to deal with inclined fractures by using an embedded discrete fracture model

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