A Study of Relative Permeability for Steam-Water Flow in Porous Media

Abstract

We report on continuing experimental and numerical efforts to obtain steam-water relative permeability functions and to assess effect of heat transfer and phase change. To achieve these, two sets of steadystate flow experiments were conducted: one with nitrogen and water and another with steam and water. During these experiments, a mixture of nitrogenwater (or steam-water) was injected into a Berea sandstone core. At the onset of steady state conditions, three-dimensional saturation distributions were obtained by using a high resolution X-ray computer tomography scanner. By identifying a length of the core over which a flat saturation profile exists and measuring the pressure gradient associated with this length, we calculated relative permeabilities for nitrogen-water flow experiments. The relative permeability relations obtained in this case were in good agreement with those reported by other investigators. Another attempt was also made to conduct a steamwater flow experiment under adiabatic conditions. This experiment was completed with partial success due to the difficulties encountered during the experiment. The results of this experiment showed that a flat saturation profile actually developed over a substantial length of the core even at a comparatively modest injection rate (6 grams per minute) with low steam quality (4% by mass). The completion of this set of experiments should yield steam-water relative permeability relations in the near future.