Nonlinear fluid flow through three-dimensional rough fracture networks:Insights from 3D-printing,CT-scanning,and high-resolution numerical simulations
Nonlinear fluid flow through three-dimensional rough fracture networks:Insights from 3D-printing, CT-scanning, and high-resolution numerical simulations作者机构:Key Laboratory of Rock Mechanics and Geohazards of Zhejiang ProvinceShaoxing UniversityShaoxing312000China State Key Laboratory for Geomechanics and Deep Underground EngineeringChina University of Mining and TechnologyXuzhou221116China School of EngineeringNagasaki UniversityNagasaki852-8521Japan
出 版 物:《Journal of Rock Mechanics and Geotechnical Engineering》 (岩石力学与岩土工程学报(英文版))
年 卷 期:2021年第13卷第5期
页 面:1020-1032页
核心收录:
学科分类:08[工学] 080104[工学-工程力学] 0815[工学-水利工程] 0801[工学-力学(可授工学、理学学位)]
基 金:the Natural Science Foundation of Zhejiang Province(Grant No.LR19E090001) the Natural Science Foundation of China(Grant Nos.42077252,42011530122,and 51979272)
主 题:Nonlinear flow 3D-printing CT-scanning Fracture network Permeability Fluid flow test
摘 要:Nonlinear flow behavior of fluids through three-dimensional(3D)discrete fracture networks(DFNs)considering effects of fracture number,surface roughness and fracture aperture was experimentally and numerically *** physical models of DFNs were 3D-printed and then computed tomography(CT)-scanned to obtain the specific geometry of *** validity of numerically simulating the fluid flow through DFNs was verified via comparison with flow tests on the 3D-printed models.A parametric study was then implemented to establish quantitative relations between the coefficients/parameters in Forchheimer’s law and geometrical *** results showed that the 3D-printing technique can well reproduce the geometry of single fractures with less precision when preparing complex fracture networks,numerical modeling precision of which can be improved via CT-scanning as evidenced by the well fitted results between fluid flow tests and numerical simulations using CT-scanned digital *** in DFNs become increasingly tortuous as the fracture number and roughness increase,resulting in stronger inertial effects and greater curvatures of hydraulic pressure-low rate relations,which can be well characterized by the Forchheimer’s *** critical hydraulic gradient for the onset of nonlinear flow decreases with the increasing aperture,fracture number and roughness,following a power *** increases in fracture aperture and number provide more paths for fluid flow,increasing both the viscous and inertial *** value of the inertial permeability is approximately four orders of magnitude greater than the viscous permeability,following a power function with an exponent a of 3,and a proportional coefficient b mathematically correlated with the geometrical parameters.