Calculating method for relative permeability curve of polymer flooding

The Blake-Kozeny equation was amended in this paper, and on the basis of this fractional flow equation and displacement front equation, and the relationship between visible viscosity and multiple of water injection, the average water saturation and the end water saturation were presented by considering of the influence of consistency coefficient of polymer solution H, power-law index n, inaccessible pore volume, the physical character of porous medium and flooding velocity in experiment, and then a new calculating method of relative permeability curve of polymer were presented. The result shows that by this new method, the relative permeability of oil phase was basically the same as that derived in JBN method, while the relative permeability of water was higher. In the flooding course, the effective viscosity of polymer solution firstly decreased, and then increased with the increasing of saturation rate.