An efficient 3D cell-based discrete fracture-matrix flow model for digitally captured fracture networks  

作　　者：Lei Sun Mei Li Aly Abdelaziz Xuhai Tang Quansheng Liu Giovanni Grasselli 

机构地区：[1]Department of Civil and Mineral Engineering,University of Toronto,Toronto,ON M5S 1A4,Canada [2]School of Civil Engineering,Wuhan University,Wuhan 430072,China

出　　处：《International Journal of Coal Science & Technology》2023年第5期87-106,共20页国际煤炭科学技术学报（英文）

基　　金：supported by the Natural Sciences and Engineering Research Council of Canada(NSERC)with NSERC/Energi Simulation Industrial Research Chair program,NSERC Discovery 341275,and CRDPJ 54389419.

摘　　要：Complex hydraulic fracture networks are critical for enhancing permeability in unconventional reservoirs and mining indus-tries.However,accurately simulating the fluid flow in realistic fracture networks(compared to the statistical fracture net-works)is still challenging due to the fracture complexity and computational burden.This work proposes a simple yet efficient numerical framework for the flow simulation in fractured porous media obtained by 3D high-resolution images,aiming at both computational accuracy and efficiency.The fractured rock with complex fracture geometries is numerically constructed with a cell-based discrete fracture-matrix model(DFM)having implicit fracture apertures.The flow in the complex fractured porous media(including matrix flow,fracture flow,as well as exchange flow)is simulated with a pipe-based cell-centered finite volume method.The performance of this model is validated against analytical/numerical solutions.Then a lab-scale true triaxial hydraulically fractured shale sample is reconstructed,and the fluid flow in this realistic fracture network is simu-lated.Results suggest that the proposed method achieves a good balance between computational efficiency and accuracy.The complex fracture networks control the fluid flow process,and the opened natural fractures behave as primary fuid pathways.Heterogeneous and anisotropic features of fluid flow are well captured with the present model.

关 键 词：Fractured porous medium-Flow simulation Digital image Cell-based DFM Finite volume method 

分 类 号：TD82[矿业工程—煤矿开采]