TY - JOUR T1 - A Hybrid Upscaling Procedure for Modeling of Fluid Flow in Fractured Subsurface Formations AU - B. Gong & G. Qin JO - International Journal of Numerical Analysis and Modeling VL - 3 SP - 667 EP - 683 PY - 2012 DA - 2012/09 SN - 9 DO - http://doi.org/ UR - https://global-sci.org/intro/article_detail/ijnam/653.html KW - fractures, porous media flow, multi-scale, upscaling. AB -
Natural fractures reside in various subsurface formations and are at various length
scales with different intensities. Fluid flow in fractures, in matrix and between matrix and fractures
are following different flow physics. It is thus a great challenge for efficiently modeling and
simulation of fluid flow in fractured media due to the multi-scale and multi-physics nature of the
flow processes.
Traditional dual-porosity and dual-permeability approach represents fractures and matrix as
different continuum. The transfer functions or shape factors are derived to couple the fluid flow
in matrix and fractures. The dual-porosity and dual-permeability model can be viewed as a
multi-scale method and the transfer functions are used to propagate fine-scale information to the
coarse-scale reservoir simulation. In this paper, we perform a detailed study to better understand
the optimal way to propagate the fracture information to the coarse-scale model based on the
detailed fracture characterization at fine-scale.
The Discrete Fracture Modeling (DFM) approach is used to represent each fracture individually
and explicitly. The multiple sub-region (MSR) method is previously used for upscaling
calculations based on fine-scale flow solution by finite volume method on the DFM. The MSR
method is the most appropriate upscaling procedure for connected fracture network but not for
disconnected fractures. In this paper, we propose an adaptive hybrid multi-scale approach that
combines MSR and DFM adaptively for upscaling calculation for complex fractured subsurface
formations that usually involve both connected fracture network and disconnected fractures. The
numerical results suggest that adaptive hybrid multi-scale approach can provide accurate upscaling
results for flow in a complicated geological system.