Pressure dependent porosity

Overview

This model assumes a simple exponential law for the porosity as function of pressure, i.e.

$\phi = \phi_{ref} \, exp ( c \cdot ( p - p_{ref} ) )$

where $\phi_{ref}$ is the reference porosity at reference pressure, $p_{ref}$ , $p$ is the pressure and, $c$ is the compressibility.

Parameters

The following attributes are supported:

Name	Type	Default	Description
compressibility	real64	required	Solid compressibility
defaultReferencePorosity	real64	required	Default value of the reference porosity
name	groupName	required	A name is required for any non-unique nodes
referencePressure	real64	required	Reference pressure for solid compressibility

Example

<Constitutive>
   ...
   <PressurePorosity name="rockPorosity"
                     referencePressure="1.0e27"
                     defaultReferencePorosity="0.3"
                     compressibility="1.0e-9"/>
   ...
</Constitutive>