用启动压力梯度确定低渗储层地下流体易流动范围

在低渗透油藏中,流体的渗流往往表现出对达西定律的一定偏离,存在着启动压力梯度。从非达西渗流规律和等产量一源一汇渗流理论出发,推导了注采单元主流线中点处的最大压力梯度计算公式,结合启动压力梯度与渗透率的关系,进而建立了低渗透油藏中地下流体可以流动的条件,从而得到廊东油田地下流体的流动半径情况,为注水开发中注采半径的确定提供了依据。

Determination of the Easy Flowing Range of Subsurface Fluid in the Low Permeability Reservoir According to the Start-up Pressure Gradient

The seepage flow of fluids in low permeability media often deviates Darcy~
＇s Law in some extent,existing the start- up pressure gradient. The formula of the maximum pressure gradient in the middle of the largest mainstream line of the injection - production unit was deduced from the non - Darcy seepage rule and the seepage theory of the same yield of a source and a remittance. Combining with the relationship of the start - up pressure gradient and permeability, the easy flowing conditions of subsurface fluid were determined, ,then the subsurface fluid easy flowing semidiameter of the Langdong oil field was gained, which can provide a basis to make sure the radius of injection - production in the waterflooding.