Coexistence of Shear and Elongational Components of Flow Paths through Porous Media during Polymer-Flooding Applications

Abstract

Although the flow field at pore level is not an ideal elongational flow due to the presence of shear and rotation, the increase in flow resistance is referred to as an elongation-thickening effect. Several arguments have been presented in the literature to explain shear or elongational behaviour. One argument is that viscoelastic flow (non-Newtonian) in porous media differs from Newtonian flow, primarily because the converging-diverging nature of flow in porous media gives arises to normal stresses which are not solely proportional to the local shear rate. A second argument is that any geometry involving a diameter change will generate a flow field with elongational characteristics and hence both will exist. Despite of this diversity a general consensus might agree that the elongational and shear properties of the fluid coexist. The aim of this investigation is to establish the comparison whether elongational effects have strong impact or shear effects. The nature of this work is based on the review of publications and laboratory data. Firstly theoretical approach is depicted based on concepts description and theories. Secondly experimental approach is discussed comparing different experiments to better understand the dominance of viscous or elongational force. Finally, effect of brine and temperature is analysed