Advances in computation of local problems for a flow-based upscaling in fractured reservoirs

55/2015

Advances in computation of local problems for a flow-based upscaling in fractured reservoirs

Monday 2nd November 2015

Fumagalli, A.; Zonca, S.; Formaggia, L.

In this article we present some advances to increase the efficiency and applicability of a flow-based upscaling procedure to solve single and multi-phase flows in natural fractured reservoirs. These geological formations may be characterized by hundreds up to hundreds of thousands of fractures, ranging from small to medium scales, which spread all the reservoir. An explicit representation of all the fractures in real scenarios make soon unfeasible performing numerical simulations. An upscaling procedure is thus required. We assume that the reservoir can be modeled with a coarse corner-point grid where the fractures are geometrically uncoupled, by using an embedded discrete fracture model. To describe the scaled up problem, we consider a flow-based upscaling procedure where multiple sub-regions are used to derive transmissibilities, mean depths and pore volumes related to the coarse degrees of freedom associated with fractures and rock matrix. Our focus is to further enhance the upscaling process by allowing the splitting of unconnected rock matrix regions and to compare two ways of setting up the local problems used to compute the transmissibility between coarse cells. Numerical examples confirm the effectiveness of the proposed approach.

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SI:MAMERN VI-2015