Abstract: Considering factors as two-phase of oil and water, production history, areal heterogeneity of the reservoir, well-bore storativity and skin, we establish a mathematical well testing model with polymer flooding in producing period and a streamline model for unsteady well testing. Numerical solutions are gained by a stream-tube method. It shows that the pressure derivative curve moves upward with the increase of the ratio of oil/water viscosity. The effective permeability of formation decreases with an increase of production time. The effect of water-oil front cannot been reflected from the derivative curve in the water well drawdown log-log plot when a high permeable zone is distributed along the main streamline. The concave in derivative curve appears earlier with the increase of concentration of polymer injected.

Key words: polymer flooding, two phase well testing, streamline model, numerical well test