《启动压力梯度对单相及两相渗流规律的影响》-毕业论文（设计）.doc

PAGE 摘　要 本文在前人研究的基础上，进行了考虑启动压力梯度的稳定渗流规律研究。 研究了单向流非达西渗流规律。获得了压力分布公式和流量公式。通过分析表明，对于平面单向流，在沿程渗流过程上压力消耗是均匀的，压力梯度为常数。与达西流相比，含启动压力梯度时，压力梯度大，压力降落快。 研究了平面径向流非达西渗流规律。获得了压力分布公式、平均压力公式和流量公式。通过分析表明，对于平面径向流，压力主要消耗在井底附近。与达西流相比，含启动压力梯度时，压力梯度大，压力降落快。 研究了含启动压力梯度的油水两相渗流规律，通过研究表明在其他参数不变的情况下，注入速率增大，含油饱和度减小，驱替含水饱和度增大，驱替效率提高。在低渗透油田中，由于渗透率极低，油层参数和流体的性质很难改变。因此，要尽可能增大注入速率，以取得更好的驱替效果。 关键词：非达西流；启动压力梯度；平面单相渗流；平面径向流；稳定渗流 Abstract In this paper, the law of steady flow with staring pressure gradient is studied on the basis of the researches before. The law of Non-Darcy single-phase flow is studied. The equations of pressure distribution and flow rate are obtained. Through analysis it is shown that for the plane single-phase flow the depletion of pressure is homogeneous in the process of flow, starting pressure gradient is a constant. Compared with Darcy flow, the bigger the starting pressure gradient is, the faster the velocity of the pressure drawdown. The law of Non-Darcy plane radial flow is studied. The equations of pressure distribution, average pressure and flow rate are obtained. Through analysis it is shown that for the plane radial flow, the pressure depletes near the bottom hole. Compared with Darcy flow, the bigger the starting pressure gradient is, the faster the velocity of the pressure drawdown. The law of two-phase flow with starting pressure gradient is studied, through analysis it is shown that in the condition that other parameters are constant, if injection rate increases, the oil saturation decreases and the displacement efficiency is enhanced. In low permeability oilfield, reservoir parameters and the property of fluid are difficult to be changed for the low permeability. Therefore, the injection rate should be improved as much as possible; the better displacement effect will be obtained. Key words: Non-Darcy flow; Starting pressure gradient; Plane single-phase; plane radial flow; Steady flow 前 言 随着人类对能源需求量的日益增加，对作为目前主要能源的石油和天然气产量提出了更高要求，世界上许多生产石油的国家都有一个共同的发展趋势，就是在石油工业初