Upscaling single phase permeability

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This program is a part of the opm-upscaling module.

The permeability field for an Eclipse corner point grid is upscaled to one anisotropic permeability tensor representing the model.

The resulting permeability tensor depends on the boundary conditions chosen:

  • Fixed boundary conditions: Assume no flow along the sides of the geometry parallel to the pressure drop direction. Produces a diagonal permeability tensor.
  • Linear boundary conditions: Assumes linear pressure drop along the sides of the geometry parallel to the pressure drop direction. Produces a non-symmetric full-tensor permeability.
  • Periodic boundary conditions: Assumes that any flow out the sides (parallel to pressure drop direction) of the model flow into the model on the opposite side. Produces a symmetric full-tensor permeability.

Syntax

$ upscale_perm gridfile.grdecl

The gridfile.grdecl is a corner point grid with permeability values given with keywords inside grdecl-file.

Option Description Default value
output Output resulting text to this file as well as standard output none
bc Which boundary conditions to compute for. Possible values are any of the letters flp, meaning fixed, linear and periodic. f

Example:

$ upscale_perm -bc p -output upscaledperm.txt gridfile.grdecl

Input permeability

It is possible to model each cell with isotropic or anisotropic permeability. This are controlled by keywords used in Eclipse gridfile. Possible options:

  1. Only PERMX specified: assumes isotropic input, one permeability value for each cell
  2. PERMX, PERMY and PERMZ specified: each cell is modelled with diagonal permeability tensor
  3. PERMXX, PERMYY, PERMZZ, PERMXY, PERMYZ and PERMZX specified: each cell is modelled by symmetric full tensor permeability

The cell tensor permeability is with respect to the global x, y and z-directions for the global grid coordinate system.

Source code

Input link to source code here when available