双渗介质油藏抽汲井测试资料数值试井分析

Numerical Well Test Analysis on Testing Information of Double Permeability Medium Reservoir Swabbing Well

由于抽汲井的开采工艺特点而导致的井底压力变化是非常复杂的。对这类井,若采用以往自喷井建立的数学模型进行解释,难以准确地描述整个地层压力变化过程。建立圆形封闭地层中心一口抽汲井的定产量试井模型,在考虑井筒储集效应和表皮系数的情况下,用块中心网格隐式差分格式对数学模型进行离散后求出数值解,用该模型对m13井进行解释,结果表明该模型可以较好地反映井底压力复杂的变化过程,能较准确地解释双渗介质油藏抽汲井生产的非自喷井流动期或恢复期的测试资料。

Bottom hole pressure change resulting from exploration process characteristics of swabbing wells is very complicated.For this kind of wells,it is difficult to describe the whole formation pressure change process if the mathematical model established for flowing wells is applied.Established is the determined production well test model for one swabbing well located in the circular confining bed center.Considering well bore storage effect and skin factor,block-centered grid implicit difference scheme is applied to disperse the mathematical model for evaluating numerical solution.This model is applied to explain Well m13 and its results show that the model can better reflect complex change process of bottom hole pressure and can accurately explain test data produced in flow or restoration stage of un-flowing well in double permeability medium reservoir swabbing well.