Gravity Override of Immiscible Fluids in Porous Media

Abstract

When one fluid is displaced by another in a permt!llble medium, the front between the two fluids changes its shape. The change in shape of the front depends on miscibility of the two fluids, the density difference, and the time of contact. Inside a petroleum reservoir, when oil is pushed with a fluid, the front's changed shape is one of the important factors in determining the efficiency of the production system. Therefore, it is important to study the changing shape of the front, in order to extract oil in an efficient manner. Using Darcy's law and the convection-diffusion equation, a detailed mathematical study of the motion of the front and the fluid particles is presented fvr miscible fluids. The model is then restricted to immiscible fluids and numerical results are presented. This paper describes how the front between two fluids changes its shape because of a difference in density.