应力敏感油藏中考虑启动压力和二次梯度的非线性渗流模型  

A Nonlinear Seepage Flow Model of Stress-sensitive Reservoir Under Considering the Start-up Pressure Gradient and the Quadratic Pressure Gradient

作　　者：张晓荣[1] 张鹏 章双龙[1] 庞辉[1] 

机构地区：[1]油气藏地质及开发工程国家重点实验室西南石油大学,四川成都610500 [2]陕西延长石油(集团)有限责任公司研究院,陕西西安710075

出　　处：《辽宁化工》2013年第8期921-923,共3页Liaoning Chemical Industry

基　　金：国家科技重大专项;项目号:2008ZX05054

摘　　要：从质量守恒原理出发,详细推导出了应力敏感油藏中考虑启动压力梯度和二次压力梯度非线性不稳定渗流偏微分方程。并通过变量代换,将渗流方程拟线性化,最后利用Douglas-Jones预估-校正法求得模型的数值解。讨论了不同参数变化时井底压力的变化规律,做出了典型压力曲线图版。曲线在形态和特征上与线性模型曲线明显不同,不再遵循"0.5线"规则和"单位斜率"规则。启动压力梯度因子影响压力降落曲线晚期上翘段的斜率,该因子越大,曲线上翘程度越大,当其很小时,压力导数曲线出现水平直线段。The partial differential equation of the nonlinear seepage flow in stress-sensitive reservoir under considering the start-up pressure gradient and quadratic pressure gradient was deduced based on the mass conservation principle.And then through quasilinearizating the seepage flow equation with variable substitution,the numerical solution of the seepage flow model was obtained by Douglas-Jones predictor corrector method.The changing rule of pressure under various parameters was discussed.The plot of typical pressure curves was given.The form and characteristics of the curve are different from ones of linear model curve,no longer following＂0.5 line＂ rule and ＂unit slope＂ rule.Start-up pressure gradient factor affects the slope of pressure drawdown curve in the later;The bigger this factor value is,the greater curve upwarp level is.When this factor value is very little,the pressure derivative curve appears horizontal straight section.

关 键 词：启动压力梯度 二次梯度 非线性渗流 应力敏感 预估-校正法 

分 类 号：TE122[石油与天然气工程—油气勘探]