This paper presents a study on the dynamics of fluid flow in highly porous media with low Reynolds numbers. The validity of the Darcy equation is questionable for these media, while the Brinkman equation, which is still little used for hydrocarbon flow, is proposed as an alternative. In this work we developed a numerical flow simulator, capable of representing single-phase (oil) and two-phase flow (water-oil) following both equations. For a variety of representative cases the results of these equations are compared. The application of this study is for karstified petroleum reservoirs. No influence of the Brinkman viscous term on conventional porous media is observed, but where high permeabilities values are attributed to the medium of high ...