Study on the New Determined Method of Profile Inversion of Polymer Flooding

Inversion happened in reservoir water injection profile is a bad phenomenon for enhance oil recovery, understanding the mechanism of profile inversion could provide theoretical basis for administer profile inversion. The calculation method of dynamic RF was deduced by Darcy's law, and indoor core physical simulation experiment in parallel at the same time. The results show that profile inversion lies on the different patterns of dynamic RF of polymer solution in the high and low permeable core. In the low permeable core, RF rises in the index form, while RF rises in the logarithm form in the high permeable core. In the low permeable core, the changing rate of RF continuously increases, while the changing rate of RF decreases constantly in the high permeable core. When those are equal, the water injection profile begins to invert. In this paper, a new method to predict profile inversion was sought out.