Hydraulic Properties Card Options (W)

Permeability

This is the default specification. Permeability is computed as the product of the rock intrinsic permeability and the permeability reduction factor. A primary assumption of the simulator is that principal components of the intrinsic permeability tensor are aligned with the principal coordinate directions. For cylindrical coordinate systems the radial, azimuthal, and vertical permeabilities correspond with the x-, y-, and z-direction values, respectively. The permeability tensor in eSTOMP-W has zero off-diagonal elements, requiring the specification of intrinsic permeability in the three principal axis directions, but intrinsic permeabilities for inactive principal directions are not required. For example, in a one-dimensional radial problem, only the intrinsic permeability in the radial direction needs to be specified. Default units of m² are applied to null entries for the units associated with permeability values. 

Symbols
	intrinsic permeability, m2
	saturated hydraulic conductivity, m/s
	dynamic viscosity of fluid, kg/m s
	density of fluid, kg/m3
	acceleration due to gravity, m/s2

Hydraulic Conductivity

If units of hydraulic conductivity are specified (using the keyword hc), the intrinsic permeability is computed assuming that the hydraulic conductivity was specified for the density and viscosity of water at 25˚C and 1 atm.

Sub-Options

Either or both of the following options can be used with either the Permeability or Hydraulic Conductivity Option.

IJK Indexing If the IJK Indexing option is specified in the Rock/Soil Zonation Card, then the saturation functions and any or all associated parameters can be specified either as a single value that will be applied to each node in the domain, or in an external file with the values for every grid-cell ordered according to the IJK indexing scheme. Units shown in the input line will be applied to all parameters in the external file.  Info Note that eSTOMP does not support JKI and KIJ indexing. Unlike STOMP, IJK indexing does NOT need to be declared in the Rock/Soil Zonation Card in order to be used during external file reads for other cards. For example, explicit zonation may be used to specifiy the rock/soil zones, while IJK Indexing may be used to assign heterogeneous hydraulic properties to all nodes.

Dual Porosity/Permeability Model for Fractured Systems If the key words 'dp,' 'dual porosity,' or 'fractured' appear in the rock/soil name specified in the Rock/Soil Zonation Card, this indicates a dual porosity medium and the reading of both matrix and fracture properties (e.g., Fracture and Matrix Intrinsic Porosity) is triggered.

Permeability Reduction Models for Reactive Transport

When using the EckeChem module to simulate reactive transport, the permeability or hydraulic conductivity can be increased or reduced due to mineral dissolution/precipitation. The following permeability alteration models are available if porosity alteration is specified as an EckeChem sub-option in the Solution Control Card.

Kozeny-Carman Relationship A well-known relationship between permeability and porosity was proposed by Kozeny (1927), and later modified by Carman (1937) and is known as the Kozeny–Carman (KC) equation: The KC relation works well for relatively homogeneous porous media. For more complex materials, the relation has some drawbacks because of the complicated microstructure of hydrates and non-uniformed size of the pores. Nevertheless, the KC equation is commonly used in concrete literature. The Carman-Kozeny equation is based on a capillary tube model and is often presented as permeability versus porosity, grain size, and tortuosity. When it is used to estimate permeability evolution versus porosity, some of these arguments (e.g., the grain size and tortuosity) are held constant, and the equation can be reduced to: Symbols intrinsic permeability, m2 initial intrinsic permeability, m2 porosity initial porosity mean particle size, m