Mechanistic Studies of Forced Gravity Drainage Using Dimensionless Groups

A number of forced gravity drainage experiments have been conducted using a wide range of the physical and operational parameters, where the type, length and permeability of the porous medium as well as oil viscosity and injection rate were varied. Results indicate that an increase in Bond number has a positive effect on oil recovery whereas capillary number has an opposite effect. Furthermore, it was found that use of each number alone is insufficient to obtain a satisfactory correlation with recovery. A combined dimensionless group is proposed that combines the effect of all three forces. The exponent of the Bond number in the proposed group is larger than the capillary number suggesting a larger importance for the former. We then show that the same group provides a good correlation for recovery from addition experiments conducted in this work and another set of experiments in the literature.