双重介质油藏基质动用程度及规律

摘要

采用数值模拟方法,对双重介质油藏中基质动用机制、程度及影响因素进行研究.针对ECLIPSE数值模拟软件不能给出基质产油量的情况,首次提出用饱和度变化计算基质累积产油量的方法和基质贡献率的概念,研究基质的动用程度,分析块度系数、基质渗透率、裂缝渗透率、注水速度等因素对水驱基质贡献率的影响.结果表明:裂缝发育程度是决定基质动用程度的主要因素,裂缝越发肓越能发挥基岩的渗吸排油作用,基质贡献率越高;基质渗透率越高,基质贡献率越高;裂缝渗透率对基质贡献率的影响较小;注水速度越低,越能发挥基质的渗吸排油作用.%The matrix producing mechanism, degree and influencing factors in dual-porosity reservoir were studied by numerical simulation method. Since the software of ECLIPSE can not calculate the matrix production, a new method for calculating the matrix cumulative oil production using saturation change was proposed. The concept of matrix contribution rate was introduced to research the matrix producing degree. The effect of size index, matrix permeability, fracture permeability, water injection rate on the matrix contribution rate of water flooding was analyzed. The results show that the degree of fracture development is the main factor affecting the matrix producing degree. The more the fracture developed in the reservoir, the more obvious the effect of imbibitions oil-drain in matrix and the higher the matrix contribution rate is. The higher matrix permeability, the higher matrix contribution rate is. Fracture permeability has relative small effect on the matrix contribution rate.The lower water injection rate, the better matrix imbibitions oil-drain effect is.