选取上随体Maxwell本构方程建立黏弹性流体在微孔道中的流动方程,运用控制体积法和交替方向隐式(ADI)方法得到流场的数值解,计算流动的速度场和应力场,分析不同弹性驱替液作用在残余油滴上的驱替力,以及不同弹性驱替液驱替时残余油滴的变形,从水动力学角度探索聚合物溶液所具有的弹性驱替残余油滴的水动力学机制.结果表明:与无弹性的驱替液相比,黏弹性驱替液作用在残余油滴上的法向应力和水平驱替力都更大,而且流场的应力分布也产生突变；在压力梯度相同的情况下驱油时,水、幂律流体、黏弹性聚合物溶液(威森伯格数We=0.3)对残余油滴的推力之比约为1∶8∶20；黏弹性驱替液会使油滴产生更大的变形,驱油效果会更好.%In order to analyze the microscopic stress field acting on residual oil droplets in micro pores, calculate its deformation, and explore the hydrodynamic mechanism of viscoelastic fluids displacing oil droplets, the viscoelastic fluid flow equations in micro pores were established by choosing the upper-convected Maxwell constitutive equation. The numerical solutions of the flow field were obtained by volume control and alternate direction implicit methods. The velocity field and microscopic stress field, the forces acting on residual oil droplets, the deformations of residual oil droplets by various viscoelastic displacing fluids were calculated and analyzed. The results demonstrate that both the normal stress and horizontal force acting on the residual oil droplets by viscoelastic fluids are much larger than those of inelastic fluid. The distribution of normal stress changes abruptly. Under the condition of the same pressure gradient, the ratio of the horizontal forces acting on the residual oil droplets by different displacing fluids which are water, the power-law fluid and viscoelastic fluid with Wesson Borg number of 0.3 is about 1:8 :20. The viscoelastic fluids cause the residual oil droplet to deform significantly, and the flooding is better.
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