低渗透储层压裂开发的油藏数值模拟研究

根据非达西渗流规律,通过引入任意分布的压裂改造后的人工裂缝综合考虑了各种影响因素,建立了一种新型的非线性复合渗流模型,并对其进行了求解,编制了程序,验证了其可行性和可靠性。该模型可用于双重介质或单重介质地层压裂前后生产动态的模拟,既能描述线性的达西渗流现象,又能描述低渗透和高渗透两种情况下的非线性渗流问题。模型中考虑了渗透率随孔隙压力指数变化的时变效应、实际中可能的任意压裂裂缝方位(方向、倾角)和压裂裂缝导流能力随时间呈指数或半对数规律下降的情况。可用于模拟多缝及非对称压裂缝条件下的生产动态和单井压裂、单井重复压裂、整体压裂、开发压裂及整体重复压裂的油藏生产动态。

Numerical simulation for development of low-permeability reservoir

On the basis of non-Darcy's flow,a new nonlinear mathematical model for porous flow was proposed and solved.The possibility of the model was proved.This model can describe the linear Darcy's flow and the nonlinear flows including low-permeability and high-permeability flow in fracture.In the model,the permeability changing with the effective porosity pressure in mass media and the fracture conductivity changing with time were considered.This model can be used to predict pre-fracturing and post-fracturing performances.It can also be used to simulate dual-porosity media and the pre-fracturing and post-fracturing performances of low-permeablility reservoir with various fractures.