Flow of a Fluid through a Porous Solid Due to High Pressure Gradients

It is well known that the viscosity of fluids could vary by several orders of magnitude with pressure. This fact is not usually taken into account in many important applications involving the flow of fluids through a porous media, like the problems of enhanced oil recovery or carbon dioxide sequestration where very high pressure differentials are involved. Another important technical problem where such high pressure differentials are involved is that of extracting unconventional oil deposits such as shale which is becoming ever so important now. In this study, we show that the traditional approach that ignores the variation of the viscosity and drag with the pressure greatly over-predicts the mass flux taking place through the porous structure. While taking the pressure dependence of viscosity and drag leads to a ceiling flux, the traditional approaches lead to a continued increase in the flux with the pressure difference. In this study, we consider a generalization of the classical Brinkman equation that takes the dependence of the viscosity and the Drag coefficient on pressure. To our knowledge, this is the first study to carry out such an analysis.