变形双重介质油藏动态特征

在应力敏感油藏的试井分析中 ,常岩石特性的假设对于确定传导率和储存系数可能引起较大的误差。研究了应力敏感地层中双重介质油藏的动态特征 ,建立了应力敏感地层双重介质的新的数学模型。在考虑裂缝发生形变时渗透率依赖于孔隙压力变化的流动方程是强非线性的前提下 ,采用Douglas Jones预估 校正法获得了只有裂缝发生形变定产量生产时无限大地层线源井和定压生产时无限大地层圆柱面源井的数值解 ,并探讨了变形参数和双重介质参数变化时压力的变化规律 ,给出几种情况下典型压力曲线图版。这些结果为变形介质试井参数解释提供了理论依据

DYNAMIC CHARACTERISTICS OF RESERVOIR WITH DEFORMED DOUBLE-POROSITY MEDIUM

The assumption of constant rock properties in well test analysis of stress-sensitive reservoirs can often cause significant errors in determination of reservoir transmissibility and storativity. The pressure transient response of the double-porosity medium permeability in stress-sensitive reservoirs is studied. A new mathematical model of the double\|porosity medium is established in consideration with the double-porosity features of oil reservoir and the deformation of medium in stress-sensitive reservoirs. The dependence of permeability on the pore pressure makes the flow equation become strongly nonlinear. The numerical solutions for the constant-pressure production of a cylinder source well and the constant-rate production of a line source well are obtained by using Douglas-Jones predictor-corrector method. The change rules of pressure with the change of double-porosity parameters and deformation parameters are analyzed. The plots of typic pressure curves in a few cases are given. The results can provide theoretical basis and method for interpreting well-test parameters of deformation media flow.