Gas-water Model Characteristic curves

The gas-water model requires the definition of a capillary pressure curve for the interface between the gas and the water phases, and relative permeability for the water and the gas in water. An example is:

CHARACTERISTIC_CURVES gas_water_example
  TABLE swfn_table
    PRESSURE_UNITS Bar
    EXTERNAL_FILE swfn_file.dat
  END
  TABLE sgfn_table
    PRESSURE_UNITS Bar
    EXTERNAL_FILE sgfn_file.dat
  END
END

Where the file “swfn_file.dat” contains the water saturation table:

SWFN
  0.0    0    0.4
  0.1    0    0.3
  0.9    1    0.2
  1.0    1    0.1
/

The file “sgfn_file.dat” contains the gas saturation table:

SGFN
 0.0      0       0
 0.10    0.0      0
 0.255   0.15     0
 0.51    0.4      0
 0.765   0.8      0
 1.0     1.0      0
/

Note that the capillary pressure entered with the water function table will be used as the aqueous phase/gas phase capillary pressure. The capillary pressure entered with the gas function table will be ignored.