FLOW OF GAS THROUGH POROUS MATERIALS

Abstract

An experimental study has been made to establish quantitatively the characteristics of and laws governing the flow of gases through consolidated and unconsolidated porous materials of fine texture. Experiments were performed with columns of glass beads, homogeneous and heterogeneous unconsolidated sands, as well as with samples of actual sandstones. With the sandstones linear flows were made both perpendicular and parallel to the bedding plane. Radial flows through annular sections of the sandstone were also made. In all cases it was found that the gradient of the squares of the pressures is proportional to a power of the mass velocity. In the various cases the exponent was found to lie between the limits 1 and 2 corresponding respectively to completely viscous and completely turbulent flow in straight cylindrical tubes. For a given sand however it remains fairly constant over a considerable range in the mass velocity. On the basis of these results a theory was developed for the production from and pressure decline in a closed sand reservoir of uniform thickness producing into a well under conditions of radial two-dimensional flow. The theoretical predictions check qualitatively with the limited field data that are available.