Steady-state upscaling: From lamina-scale to full-field model

In recent years, the impact of small-scale permeability structure on hydrocarbon recovery has been demonstrated, and upscaling procedures, such as the Geopseudo Method, have been developed to scale-up from the lamina scale, using the hierarchy of geological length scales. However, upscaling is very time consuming, so many engineers still input rock curves into large-scale simulations. In this study, we show how the process may be speeded up using steady-state methods for calculating the pseudo functions. A three-stage scale-up of a fluvio-aeolian reservoir was carried out. Capillary equilibrium was assumed for the first two stages, and viscous-dominated steady-state for the third stage. Two different wettability cases were examined -water-wet and intermediate-wet. The effect of using the small-scale pseudo relative permeabilities depends on both nature of the heterogeneities and on the wettability. In this study the recovery was reduced, especially in the water-wet case.