裂缝油藏三维油、水两相渗流的有限元方法

A FINITE ELEMENT METHOD FOR 3D OIL & WATER TWO PHASE SEEPAGE FLOW IN A NATURALLY FRACTURED RESERVOIR

本文建立了一裂缝性油藏三维油、水两相的渗流模型。采用双孔隙度、单渗透率的渗流微分方程组描述裂缝系统和基质系统中流体的流动。与以往不同的是，应用有限元方法进行差分离散，并将油、水井视为单元的边界进行处理，选用任意形状六面体（曲边）单元和等参元变换以及隐式压力和隐式饱和度交替求解的方法。文中还给出了本模型对Ｋａｚｅｍｉ算例的计算对比结果。

A 3D model for oil and water two phase seepage flow in a naturally fractured reservoir has been developed. A dual porosity, single permeability seepage flow differential equation group is used to describe the fluid flow in fractures and matrix systems. Both the fracture flow equations and matrix/fracture flow equations are solved by finite element method based on Galerkin method, and well bores are taken as the boundary of the units. Hexahedron (curved line ) unit with arbitrary shape, isoparametric element conversion and implicit pressure implicit saturation alternation method can be used to obtain accurate solution. Comparison result is given for this model and Kazem's problem.