A comprehensive framework for modeling flow in porous media containing thin, discrete features, which could be high-permeability fractures or low-permeability deformation bands, is presented. The key steps of the methodology are mesh generation, fine-grid discretization, upscaling, and coarse-grid discretization. Our specialized gridding technique combines a set of intersecting triangulated surfaces by constructing approximate intersections using existing edges. This procedure creates a conforming mesh of all surfaces, which defines the internal boundaries for the volumetric mesh. The flow equations are discretized on this conforming fine mesh using an optimized two-point flux finite-volume approximation. The resulting discrete model is represented by a list of control-volumes with associated positions and pore-volumes, and a list of cell-to-cell connections with associated transmissibilities. Coarse models are then constructed by the aggregation of fine-grid cells, and the transmissibilities between adjacent coarse cells are obtained using flow-based upscaling procedures. Through appropriate computation of fracture-matrix transmissibilities, a dual-continuum representation is obtained on the coarse scale in regions with connected fracture networks. The fine and coarse discrete models generated within the framework are compatible with any connectivity-based simulator. The applicability of the methodology is illustrated for several two- and three-dimensional examples. In particular, we consider gas production from naturally fractured low-permeability formations, and transport through complex fracture networks. In all cases, highly accurate solutions are obtained with significant model reduction.

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mesh generation finegrid discretization upscaling modeling flow in porous media optimized twopoint flux finitevolume highpermeability fractures conforming fine mesh connected fracture connectivitybased specialized gridding technique transport coarse discrete models flowbased upscaling procedures gas production controlvolumes the volumetric approximate intersections fractured lowpermeability formations transmissibilities procedure intersecting triangulated surfaces coarsegrid discretization computation of fracturematrix edges dualcontinuum representation threedimensional celltocell connections lowpermeability deformation bands flow equations aggregation of finegrid cells thin discrete features internal boundaries

L.J. Durlofsky,M. Karimi-Fard,.A general gridding, discretization, and coarsening methodology for modeling flow in porous formations with discrete geological features. 96 (0),354-372.

L.J. Durlofsky,M. Karimi-Fard,"A general gridding, discretization, and coarsening methodology for modeling flow in porous formations with discrete geological features" 96

L.J. Durlofsky,M. Karimi-Fard,"A general gridding, discretization, and coarsening methodology for modeling flow in porous formations with discrete geological features"