NON-EQUILIBRIUM MODEL OF GRAVITY DRAINAGE IN A SINGLE BLOCK

This work concerns with developing a non-equilibrium model of gravity drainage in a single block. The proposed model which considers both non-equilibrium effects of capillary pressure and relative permeabilities is used for prediction of oil recovery by gravity drainage from a single block Close agreement observed between the model results and experimental data disclosed that the non-equilibrium assumption is completely reliable for modeling of gravity drainage. The results revealed that when the characteristic time of the saturation variation is comparable with the time required to establish capillary equilibrium, the non-equilibrium effects in gravity drainage must be considered. The results of this work can be potentially helpful for developing new simulation models to be used for predicting oil recovery by gravity drainage mechanism.