【作者】 邢坤； 陈明霜； 张瑞钢； 钱家忠； 吴盾；

【Author】 XING Kun;CHEN Ming-shaung;ZHANG Rui-gang;QIAN Jia-zhong;WU Dun;School of Resources and Environmental Engineering,Hefei University of Technology;Exploration Research Institute,Anhui Provincial Bureau of Coal Geology;

【机构】 合肥工业大学资源与环境工程学院； 安徽煤田地质局勘查研究院；

【摘要】 由于强烈的非均质性,自然裂隙渗透率的量化是学科领域具有挑战性的问题。先前的研究表明,单裂隙渗透率仅取决于单裂隙的几何属性。然而最近的研究表明,随着流体的流速或惯性效应的增大,单裂隙的渗透率会发生变化但其机理尚未明确。因此本研究基于有限元模拟软件Comsol Multiphsics探究了惯性效应对2D粗糙单裂隙渗透率的影响及其机理。研究结果表明:Forchheimer方程可以很好的描述粗糙单裂隙中不同惯性效应下的流体流动;随着惯性效应的增加单裂隙渗透率会随之减小,其机理是裂隙粗糙表面导致的低速区的产生和发展阻碍了流体在流道中的传输,最终导致了渗透率的降低;在低流速区中形成的涡流是水力开度波动的主要原因。最后提出了一个同时考虑单裂隙几何属性和流体惯性效应的渗透率预测模型。更多还原

【Abstract】 Due to the strong heterogeneity,the quantification of permeability of natural fracture remains a challenging problem.Previous studies showed that the permeability of a single fracture depends only on the geometric properties of the fracture.However,recent studies proved that,with the increase of fluid velocity or inertial effect,the permeability of single fracture would decrease,but the mechanism is not clear.Therefore,based on the finite element simulation software COMSOL Multiphsics,we explored the influence of inertial effect on the permeability of 2 D rough single fractures.The results showed that the Forchheimer equation could well describe the fluid flow in rough single fractures under different inertial effects;with the increase of inertial effect,the permeability of single fracture(which is characterized by hydraulic aperture)decreased.The mechanism is that the generation and development of low velocity region which induced by the rough fracture surface hindered the transmission of fluids in the flow path,and finally led to the decrease of permeability;the eddies formed in the low velocity region is the reason for the fluctuation of hydraulic aperture.A permeability prediction model considering both geometric properties and inertial effect was proposed.更多还原