Subsurface formations that arise in the simulation of gas-injection processes for enhanced oil recovery may exhibit geometrically complex features with complicated large-scale connectivity. They must be included in simulations of flow and transport because they can fundamentally impact simulation results. However, to reduce computational costs, simulations are generally performed on grids that ...

We present a reservoir simulation scheme that gives accurate resolution of both large-scale and fine-scale flow patterns. The method uses a mixed multiscale finite-element method (MMsFEM) to solve the pressure equation on a coarse grid and a streamline-based technique to solve the fluid transport on a fine-scale subgrid. Through this combination, we aim towards a numerical scheme that facilitat...

Permeability and porosity parameters of a porous medium are known only in a statistical sense. For risk assessment, one must perform multiple ow simulations of a single site, varying these input parameters. Because multiple simulations of large sites are computationally prohibitive, upscaling from ne to coarse scales is necessary. Traditional upscaling techniques determine a new eeective or ups...

Distance-based techniques have recently emerged in the context of ensemble modeling, in particular for history matching, model selection and uncertainty quantification. Starting with an initial ensemble of model realizations, a distance between any two realizations is defined. The purpose of this distance is to introduce the purpose of modeling into the process of geological modeling, thereby p...

Distance-based stochastic techniques have recently emerged in the context of ensemble modeling, in particular for history matching, model selection and uncertainty quantification. Starting with an initial ensemble of realizations, a distance between any two models is defined. This distance is defined such that the objective of the study is incorporated into the geological modeling process, ther...

In simulation of fluid injection in fractured geothermal reservoirs, the characteristics of the physical processes are severely affected by the local occurence of connected fractures. To resolve these structurally dominated processes, there is a need to develop discretization strategies that also limit computational effort. In this paper we present an upscaling methodology for geothermal heat t...

In this paper we describe an edge-directed optimization-based method for volumetric data supersampling. Our method faces the problem of partial volume effect by upscaling the volumetric data, subdividing voxels in smaller parts and performing an optimization step keeping constant the energy of each original subdivided voxel while enhancing edge continuity. Experimental tests show the good quali...

We consider upscaling of non-Darcy flow in heterogeneous porous media. Our approach extends the pressure-based numerical homogenization procedure for linear Darcy flow, due to Durlofsky, to the nonlinear case. The effective coefficients are not constants but rather mildly varying functions of prevailing gradients of pressure. The upscaled model approximates the fine grid model accurately and, i...

Traditional upscaling methods depend on local boundary conditions. It is well known that this approach may introduce large errors in the coarse model. The new method is applicable whenever these local methods fail to produce an acceptable permeability field, e.g. upscaling of blocks close to wells and cases involving heterogeneities on the coarse grid block scale. In such cases, it is impossibl...