Method for determining horizontal well fracture parameter based on PEBI (PErpendicular BIsection) mesh encryption

Abstract

The invention belongs to the technical field of oil field development fracture horizontal well parameter optimization, and discloses a method for determining a horizontal well fracture parameter based on PEBI (PErpendicular BIsection) mesh encryption. The method comprises the following steps that: designing a target block physical property parameter; on the basis of reservoir characteristics, establishing a target block geologic model; through an NWM (Near-Well Model) module in eclipse software, endowing the fracture mesh with a value; obtaining an influence comparison diagram of different fracture parameters for a recovery ratio; and determining a reasonable fracture parameter. The PEBI mesh encryption is adopted around a shaft, and the shaft can be encrypted into other PEBIs including hexagon, cylinder and the like; a hexagonal PEBI mesh is adopted, an artificial fracture of any direction can be formed, and the accuracy of a simulation result is improved; a mesh block of which the width is far smaller than the radius of the shaft replaces the fracture so as to reflect the authenticity of a formation fracture; and meanwhile, a skin factor near the shaft is set as a negative number, and a facture situation is truly simulated.

Description

technical field [0001] The invention belongs to the technical field of parameter optimization of fracturing horizontal wells in oil field development, and in particular relates to a method for determining fracture parameters of horizontal wells based on PEBI grid encryption. Background technique [0002] Due to the geological characteristics of low-permeability reservoirs are extremely low permeability, poor reservoir physical properties, large seepage resistance, and poor connectivity, it is very necessary to use horizontal wells for fracturing. Through staged fracturing of horizontal wells, a disorderly fracture network is formed in the reservoir, so as to better communicate with the formation and provide a good companion for oil and gas migration. Therefore, the selection of fracture parameters has a great impact on production. However, it is not very flexible to describe complex low-permeability oil and gas reservoirs with local grid refinement, and some grids may have n...

AI Technical Summary

Problems solved by technology

[0004] To sum up, the problems existing in the existing technology are: when the existing technology adopts right-angle grid encryption, the orientation of fractures in the grid will be inconsistent, and the fracture characteristics cannot be well described, resulting in inaccurate simulation; and it cannot pass Fracturing fractures are replaced by grid blocks whose width is much smaller than the radius of the wellbore, which reflects the authenticity of formation fractures; at the same time, the skin coefficient near the wellbore cannot be set as a negative number, so that the fracture situation can be truly simulated

Images