基于有限元的砂砾岩滤失研究

Study on glutenite filtration based on finite element

李勇明 岳文翰 罗攀2

西南石油大学油气藏地质及开发工程国家重点实验室，四川 成都 610500 陕西延长石油（集团）研究院，陕西 西安 710000

State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China Research Institute of Yanchang Petroleum Group, Xi′an 710000, China

砂砾岩非均质性极强，既有高渗透性的天然裂缝，又有渗透性很差的砾石，滤失规律非常复杂，难以用解析方式全面准确进行描述。为解决此问题，将滤失区域离散成有限个单元，单元之间的渗透性存在一定差异，而单元内部的渗透性一致，在滤失边界上施加定压边界条件，通过数值求解得到了压力分布以及壁面上的滤失速度。文中还研究了砾石体积分数和天然裂缝方向、密度等因素对滤失的影响，对简化解析模型、明确砂砾岩滤失规律具有一定意义。

Glutenite has strong heterogeneity, high permeability natural fracture and poor permeability gravel, so the rule of fluid filtration is very complex and difficult to fully and accurately be described by analytic methods. The fluid filtration zone is discretized into finite units. There are some differences between the permeability of cells and there is consistent permeability inside the cell. Byapplying constant pressure boundary condition on the boundary of  filtration zone, and  the pressure distribution and the  wall filtration velocity can be obtained through the numerical solution. This article studies the influence of gravel volume fraction, natural fracture direction and density on fluid filtration, which has certain reference significance to simplify the analytical model and know about the fluid filtration rule of glutenite.

10.6056/dkyqt201502017