| dc.description.abstract | Built on literature views and formulation of oil recovery characteristics, three cases of numerical simulation have been performed on core scale which are gravity drainage(GD) individually, capillary pressure driven spontaneous imbibition(SI) only and the interaction of them. Simulations are performed on 1 dimension with different boundary conditions, namely topopened( TO), bottom-opened(BO) and both-surface-opened(BSO).Significant oil recovery is obtained from the gravity drainage in absence of capillary pressure, while rate of oil recovering is distinctive for various parameters, for instance, peremability,height and so on.Spontaneous imbibition is sensitive to wettability and interfacial tension(IFT).The interplay of capillary pressure and gravity force under varying wettabilities and boundary conditions are differential. For boundary condition of top-opened, gravity prompts oil recovery rate at different wettabilities. In contrast, the bottom-opened cases decrease the recovery rate due to downwards gravity. In terms of final oil recovery, wettabilites and boundary condition also the determination factors for that. The final oil recovery is not sensitive to the gravity for the strongly water-wet in case of top-opened. In contrary, bottom-opened condition give rise to negative effect from gravity force, the oil recovery is reduced at smaller range of capillary pressure ;while as the water wettability reduce to neutral or even oil-wet, the final oil recovery is enhanced or reduced to some extent,manifestly. Those are determined by the gravity to capillary pressure ratio and boundary condition | nb_NO |
