关键词: 化学驱, 粘弹性流体, 幂律流体, 渗流能力, 等效渗透率, 驱油剂, 多孔介质

Abstract: The flow behavior of viscoelastic and power-law oil-displacement agent in individual pore throat model and 2D stochastic channel bundle model was studied using numerical method.The individual pore throat of reservoir was modeled as a constricted channel and expanded one,which makes up the unit of the 2D stochastic channel bundle as porous media model.The channel bundles whose size conforms to same or different probability distribution were used to model homogeneous and heterogeneous porous media.On the basis of the flow in pore throat model,the relative expressions between pressure drop and flow rate of viscoelastic fluid and power-law fluid in 2D stochastic channel bundle were presented.The percolation models of the two kinds of fluid were developed on the basis of Darcy equation.Equivalent permeability was put forward to measure the seepage ability of non-Newtonian oil-displacement agent.The results show that for the viscoelastic oil-displacement agent,the seepage ability decreases with the increase of viscoelasticity,diurnal injection,and heterogeneity and mean pore size of porous media.For the power-law fluid,percolation is the function of power-law exponent and pore structure regardless of diurnal injection.The seepage ability increases with the decrease of power-law exponent,mean pore size and heterogeneity.

Key words: chemical flooding, viscoelastic fluid, power-law fluid, percolation capacity, equivalent permeability, oil-displacement agent, porous media