基于孔隙-喉道双通道模型的油水两相流动形态分析

Flow behavior analysis of oil-water two-phase flow in pore throat doublet model

在孔隙网络模型和并联双通道模型基础上,提出一种新的孔隙-喉道双通道模型,研究油水两相流体的驱替流动,采用格子Boltzmann方法的颜色梯度模型进行模拟,重点研究不同注入速度条件下和不同宽度比的模型中,非润湿相在喉道中的流动形态变化,并对一系列不同宽度比的模型进行模拟。结果表明存在段塞流驱替的流动形态;随着注入速度的减慢,非润湿相经过双通道时存在双喉道驱替流动、段塞驱替和单喉道驱替3种流动形态变化;随着宽度比的增大,单喉道驱替的分布区间增大,段塞流和双喉道驱替出现的区间减小;多孔介质的非均质性越强,流体越容易发生卡断,驱替效果越差。

Based on a pore network model and parallel two-channel model,a pore throat doublet model was proposed to study the displacement of oil-water flow.The color gradient model of the Lattice Boltzmann method was adopted for simulation.The flow patterns of the non-wetting phase in throats were studied under different injection rates and width ratios.First,the flow pattern of the slug flow displacement was found.Secondly,as the injection velocity decreases,the non-wetting phase passed through the two channels and changed through three flow patterns of double throats displacement flow,slug displacement,and single throat displacement.Finally,a series of cases with different width ratios were simulated.It is found that as the width ratio increases,the distribution interval of single throat displacement becomes large,and the interval between slug flow and double throat displacement becomes small.It is demonstrated that that the stronger the heterogeneity of the porous media,the more easily the fluid is snapped off along with lower displacement efficiency.