摘要

The present mathematical model for polymer flooding does not consider the elasticity of polymer, and the predictive result differs a lot from the field test value. The authors build a new polymer flooding model considering the viscoelasticity of polymer and the effect of shear rate on resistance coefficient. The elastic viscosity is considered by defining a ratio of elastic viscosity and viscous viscosity. The experiments show that the exponent law model is well characterized the rheological behavior of polymer solutions, as the polymer concentration increases, the power law index n decreases, and the consistency coefficient H increases. There is a logarithmic relationship between residual resistance factor and equivalent shear rate, and the residual resistance factor and the polymer concentration also show a good linear relationship. Those new features are added in chemical flooding software UTCHEM (University of Texas at Austin, Austin, TX) to simulate polymer flooding. The results show that the ultimate recovery of polymer flooding when considering the shear rate and the elastic property is higher than that not considering it.