低渗透油藏油水两相渗流研究

用无因次分析法对低渗透岩心的实验数据进行了分析,得出新的低渗透油藏非达西渗流方程,并建立了油水两相渗流的数学模型。通过实例计算,研究了低渗透油藏中储层参数、流体特性以及开采方式等因素对注水开发效果的影响。结果表明,由于非达西渗流的影响,注水开发时容易发生指进现象,而地层倾角的增大可以削弱指进;地层原油粘度的增大会增强开采难度,而地层渗透性能的改善会使油井产能提高。因此,低渗透油藏应加密井网,强化注水以扩大生产压差,从而改善开发效果。

Oil-water two-phase fluid flow in low permeability reservoir

The results from experimental data of low permeability cores by dimensionless analysis show that the fluid flow in low permeability reservoir is non-Darcy flow. And the new non-Darcy flow equation was deduced. Based on the flow equation, the oil-water two-phase fluid flow mathematical model in low permeability reservoir was constructed. By analyzing typical examples, waterflood development effect is affected by such factors as reservoir parameters, fluid properties and development scheme. Fingering often occurs in waterflood development low permeability reservoir because of non-Darcy flow, which is weakened with formation dip increasing. And the development difficulty is enlarged with oil viscosity increasing, while productivity can be enhanced greatly by improving reservoir permeability. Closed well pattern and enhanced water injection can enlarge producing pressure drop, which are benefit to the low permeability reservoir development.