| Reservoir flows are affected by permeability heterogeneity over a range of length scales. Direct fine scale flow simulation is often not feasible due to the high resolution required. In this work, we develop and investigate new upscaling techniques for both flow and transport.; For the coarse scale modeling of flow, a new class of procedures, referred to as local-global upscaling, is developed. These methods use global coarse scale solutions to determine appropriate local boundary conditions. Transmissibility upscaling is shown to provide better accuracy than permeability upscaling in most cases. Two variants of the general procedure are introduced, specifically, coupled local-global upscaling, which considers two generic global flows, and adaptive local-global (ALG) upscaling, which applies one specific global flow. Upscaling of near-well effects is included naturally in the ALG upscaling method and a thresholding procedure is introduced to provide computational efficiency and avoid the calculation of non-physical transmissibilities. We demonstrate that the reconstruction of fine scale velocity from coarse flow solutions, as required in multiscale modeling procedures, is readily performed in the upscaling framework. The new methods are shown to provide significantly improved coarse scale flow descriptions and fine scale transport solutions (using the reconstructed velocity) for unit mobility ratio displacements.; For the coarse scale modeling of transport, we investigate and apply two related models: a pseudo relative permeability model and a generalized convection-diffusion model. Global pseudo functions are employed to study the effects of upscaled single-phase parameters and local boundary conditions on two-phase parameters. Modified local boundary conditions, specifically effective flux boundary conditions, are applied to improve the accuracy of upscaled two-phase functions. We present overall methodologies for two-phase upscaling that entail the use of locally computed transport functions in conjunction with adaptive local-global upscaling. The procedure is efficient since the upscaled two-phase parameters are computed from generic local flows. It is shown that this approach provides considerable overall improvement in accuracy over existing methods.; As practical applications, a flow-based near-well upscaling procedure for perpendicular bisection (PEBI) grids and a simplified coarse scale well model based on a well singularity analysis are also presented. |
