To obtain a reliable characterization of complexreservoirs, geoscientists and petroleum engineers commonlybuild geologic or geostatistical reservoir models which containmore than a million grid cells. However, for flow simulationsuch a detailed description demands a great deal ofinformation and processing time. Therefore, less complexmodels are usually preferred where the number of grid cellsmust be reduced by a factor of 10 or more. Such scaling upnecessarily involves the loss of information that must becaptured through upscaling porosity, permeability and the useof pseudofunctions. The main objective of this paper is todetermine a general method for using pseudofunctions forupscaling multiphase flow in 3D anisotropic heterogeneousreservoirs with different capillary and gravity numbers andapplying the method to a real field case "Hassi MessaoudField - Algeria".The performance of different types ofpseudofunctions is evaluated under different capillary andgravity numbers, and upscaling levels. As a part of thisresearch study a software package to calculatepseudofunctions has been developed. It includes: (1) the inputoption from ECLIPSE restart files (2) generates pseudo curvesfor three phase three-dimensional problems using Kyte andBerry, Pore Volume, Stone, and Transmissibility Weightedmethods, and (3) generates output file format which can beread by ECLIPSE 100?. A variety of homogeneous fine gridmodels representing different flow regimes were considered inthis study and the performance of several pseudofunctionmethods was compared. All the pseudo function methodssucceeded in reproducing the fine grid watercut andmaintained oil production for the capillary dominated,equilibrium, viscous dominated flows, however, for thegravity dominated flow they failed to match the fine gridcurve exactly. Although this shortcoming of thepseudofunction curves gives better results than the rockcurves.Next in this study, the results of the waterflood of aheterogeneous 3-D model of HMD Zone 17 are presented.This real field model confirmed the homogeneous case results:for high flow rates the pseudofunctions can be appliedsuccessfully to upscale from fine to coarse grid simulation.
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