Porous Media Primer for Physicists

Abstract

This chapter provides an introduction to concepts and fundamental relationships of pore-scale phenomena in such a way that is hoped to reduce uncertainty in understanding of porous media for a typically trained physicist without a background in the particular subject. The first topic is how and why percolation theory should be considered. Then, certain pitfalls of conventional interpretations are described. In particular we examine in detail the (casually) presumed mapping between pressure-saturation curves and the pore-size distribution, and find that complications due to finite column size, flow rates (equilibrium), and the phase connectivity described in terms of the accessibility function from percolation theory make such assumptions unjustifiable. Finally various treatments of porous media are discussed, such as capillary bundle, network, and fractal models. The serious problems associated with reliance on capillary bundle models are listed and corrections are referred to later chapters.