论文部分内容阅读
在致密气藏中 ,由于吸附水膜的影响、岩石孔隙道喉道狭窄、连通性差、渗透率极低 ,加之气液固相间表面吸附力的作用等原因 ,在低渗油藏、气藏中均存在启动压力梯度问题 ,即流体在多孔介质中的流动不再符合达西定律 ,而是遵从低速非达西渗流规律 ,四川石油管理局勘探开发研究院的室内实验已证明了这一点。在等温、单相、层流及忽略气体滑脱效应的条件下 ,气体低速非达西渗流与液体低速非达西渗流无因次渗流方程完全一样 ,但气井试井有压力法、压力平方法、拟压力法等 ,其无因次压力及无因次启动压力梯度定义均不一样 ,这给试井解释带来极大不便。文章在引入了拟体积系数概念基础上 ,再通过引入拟真实启动压力梯度的概念 ,首次实现了气井、油井低速非达西流中试井分析方程的统一 ,从而便利于低速非达西流试井分析理论的研究与教学 ,大大简化了试井分析软件的设计
In tight gas reservoirs, due to the influence of adsorbed water film, narrow throat of rock pore tunnel, poor connectivity and extremely low permeability, together with the effect of surface adsorption force between gas-liquid and solid phase, There is a problem of starting pressure gradient. That is, the flow of fluid in porous media no longer meets Darcy’s law, but follows the law of low-velocity non-Darcy seepage. This has been proved by laboratory experiments conducted by Sichuan Petroleum Administration Exploration and Development Research Institute. Under the condition of isothermal, single phase, laminar flow and ignoring the gas slippage effect, the gas non-Darcy flow at low velocity is exactly the same as the non-Darcy flow at non-Darcy flow, but there are pressure, pressure, Quasi-pressure method, the non-dimensional pressure and non-dimensional start-up pressure gradient are not the same definition, which gives interpretation of well test inconvenience. Based on the introduction of the concept of quasi-volumetric coefficient, the article first introduced the concept of quasi-real start-up pressure gradient to realize the unification of well test analysis equations in gas well and non-Darcy flow in oil well for the first time, Well analysis theory research and teaching, greatly simplifying the well test analysis software design