基于PEBI网格的离散裂缝油藏数值模拟研究  

Numerical simulation research of discrete fracture reservoir based on PEBI grid

作　　者：袁迎中[1] 向祖平[1] 戚志林[1] 严文德[1] 李继强[1] 

机构地区：[1]重庆科技学院复杂油气田勘探开发重庆市重点实验室,重庆401331

出　　处：《水动力学研究与进展（A辑）》2016年第3期379-386,共8页Chinese Journal of Hydrodynamics

基　　金：国家自然科学基金项目(51374269)~~

摘　　要：离散裂缝网络模型主要从裂缝的几何形状以及流动机理上对裂缝进行表征和描述,可以比较精确地描述裂缝特征及油藏的非均质性。该文结合油藏边界及裂缝的真实分布状态,将油藏划分为若干子区域,在每个子区域上布网格节点进行Delaunary三角剖分与Vornoni网格剖分,得到了PEBI网格。为了满足质量守恒,利用有限体积法进行了求解,对网格域和计算域之间的误差进行了修正。结合离散裂缝的数学模型及传导率计算法则,实现了高精度的离散裂缝油藏数值模拟,研究了大裂缝的分布、长短、与注采井的贯穿状况等因素对水驱油的推进方向、速度、见水时间、采出程度的影响规律。结果表明PEBI网格能准确地表征裂缝特征,再现裂缝的分布,正确地模拟裂缝影响下的水驱开发规律。Discrete fracture network model characterizes and describes geometric configuration and flow mechanism of fractures, which can accurately describe heterogeneity of fracture and reservoir. Combining with reservoir boundary and actual fracture distribution status, the reservoir is divided into several subdomain. Delannary triangulation and Vornoni gridding are completed in every subdomain, and then PEBI grid can be obtained. In order to satisfy mass conservation principle, finite volume method is used to resolve seepage differential equation, and the errors between grid domain and computational domain are corrected. Combining with discrete fracture network mathematical model and transmissibility calculation method, numerical simulation of discrete fracture reservoir can be realized. The influences of fracture distribution, length, injector-producer fracture penetration on water-drive advancing direction, velocity, water-breakthrough time, oil recovery degree are researched. The results indicate that PEBI grid can accurately describe fracture characteristics and reappear fracture distribution as well as correctly simulate water-drive development regulation under the influence of fractures.

关 键 词：裂缝性油藏 离散裂缝网络模型 PEBI网格 数值模拟 有限体积法 

分 类 号：TE319[石油与天然气工程—油气田开发工程]