Saturation functions relate the aqueous capillary pressure to aqueous saturation. Model options and parameters for these functions are specified through the Saturation Function Card. Every rock/soil type defined on the Rock/Soil Zonation Card must be referenced. With the IJK Indexing option, node dependent parameters are entered via external files and node independent parameters are entered directly on the card. Functional forms for the saturation-capillary pressure functions are preferred; however, tabular input is acceptable. By default, tabular data will be interpolated using linear interpolation, whereas values beyond the table limits will be assigned either the table minimum or maximum values appropriately.
This option accepts tabulated retention data. The default is the data of pressure head and saturation data pairs and linear interpolation is used between data points. Alternately, water content vs capillary head can be provided using the keyword "water content." Other interpolation schemes that can be specified are linear-log, cubic spline, or cubic-spline-log.
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