| The objective of this study is to develop an upscaling methodology for simulation of naturally fractured reservoirs. Tracer injection and water-oil two-phase displacement are considered. Fine grid models that explicitly incorporate fractures are built to represent the realistic fracture distribution obtained from the geostatistical characterization of fractured system. The upscaling methodology is flow based; constant pressure and constant flux boundary conditions are used. The fine grid simulation of each coarse grid is conducted first. The upscaling parameters of each equivalent dual-porosity grid are determined by matching results of the fine-grid simulation. The whole simulation domain is then filled with these equivalent values and the displacement process is simulated. The results are compared with those of the fine grid simulation over the whole domain. The effects of size of coarse grids, injection rate, well locations, absolute fracture permeability, saturation functions and water-oil viscosity ratio are tested to show the robustness and accuracy of the upscaling methodology. |
