摘要
非均质和各向异性对油藏内渗流及油井产能有明显影响。假设各向异性地层被间断面分隔成具有不同渗透率的非均质区域,利用坐标变换和镜像原理得到非均质各向异性地层渗流流动的解析解,给出了渗流特征和油藏工程分析。通过分析得出:一般情况下各向异性地层中的井点与其镜像井相对于间断面呈非对称分布,等压线在各区域内部呈椭圆形分布,但在间断面附近呈不规则分布。当相邻区域渗透率小于井所在区域渗透率时,各向异性强度越大,间断面与渗透率最大主方向夹角越大,则井控制面积越小,产量越小;反之亦然。当间断面与渗透率最大主方向夹角较大时,应适当加大井位到间断面的距离,以便增加单井的控制面积和产量;当间断面与渗透率最大主方向夹角较小时,应适当缩小井位到间断面的距离,以便提高间断面附近地质储量动用程度和最终采收率。
The nonuniform and anisotropy had notable effects on fluid flow and well productivity in the oil reservoirs.It′s supposed that the formation is divided by the discontinuity surface into different areas with different permeability values.The analytic solution of the flow in nonuniform anisotropic reservoir was obtained by the coordinate transformation and the mirror image theory.The flow characters and reservoir engineering analyses were given out.Generally in anisotropic formations,any well and its image were not symmetrical relative to the discontinuity surface.The equal pressure lines were elliptic in the inner areas but erratic near the discontinuity surface.Under the condition that the permeability ratio of the neighboring area and the well area was less than one,the bigger the angle between the discontinuity surface and the maximum principal permeability direction,or the stronger the anisotropy,the smaller the wellcontrolled area and the well production rate,vice versa.When the angle between the discontinuity surface and the maximum principal permeability direction was big,the well should be located far from the discontinuity surface so that its control area and production rates can be increased.When the angle between the discontinuity surface and the maximum principal permeability direction was small,the well should be located close to the discontinuity surface so that the producing reserves near the discontinuity surface and the ultimate oil recovery can be improved.
出处
《西南石油学院学报》
CSCD
北大核心
2005年第6期38-41,79,共5页
Journal of Southwest Petroleum Institute
基金
中国石油天然气集团公司研究项目(990509-02-06)
关键词
间断面
渗透率
坐标变换
镜像原理
渗流分析
油藏工程
discontinuity surface
permeability
coordinate transformation
mirror image theory
reservoir flow analysis
petroleum reservoir engineering
