Verification of Buckley-Leverett three-phase theory using computerized tomography

The mathematical extension of the Buckley-Leverett (B-L) theory to three immiscible fluids was presented by Grader and OʹMeara (1988). However, the three-phase flow extension of the theory has not previously been experimentally demonstrated. Fluid flow experiments are conducted through uniform glass bead packs using three immiscible liquids: water, benzyl alcohol and decane. In some experiments decane is injected into a core saturated with water and benzyl alcohol and in other experiments water is injected into a core saturated with all three phases. The recovered fluid volumes are used to calculate the in-situ saturations by applying the three-phase extension of the B-L theory. These saturations are then compared against in-situ saturations determined using X-ray computerized tomography (CT). The results show good agreement between the phase saturations determined by these two independent methods even for cases when double shocks are formed during the displacement process. They also show that the measurement of three-phase relative permeabilities using the extension of the B-L theory has both sound theoretical and experimental bases.