A New Approach for Simulating Complex Fractured Reservoirs

This paper treats a dual porosity and dual permeability system in which two grids - one each for the fractures and matrix occupy the same volume. We employ 5 pseudo components in the formulation which extends the capability beyond normal blackoil applications. The formulation also permits inert gas injection (i.e. nonhydrocarbon - N/sub 2/, CO/sub 2/, etc.) which can diffuse into the liquid phases. Moreover, the oil properties can be optionally treated as functions of pressure and API gravity. We briefly review the mathematical description of the system. We also describe a memory management scheme whereby one can study large reservoir problems (in excess of 20,000 cells) on computers offering modest core capability. Finally, we present example applications for an isolated fracture system, the effect of cyclic water injection, and the effect of variable API gravity.