Biot Porosity Model¶
Overview¶
According to the poroelasticity theory, the porosity (pore volume), , can be computed as
Here, is the porosity at a reference state with pressure and volumetric strain . Additionally, is the Biot coefficient, is the volumetric strain, is the fluid pressure and , where is the grain bulk modulus.
Parameters¶
The Biot Porosity Model can be called in the
<Constitutive>
block of the input XML file.
This porosity model must be assigned a unique name via the
name
attribute.
This name is used to assign the model to regions of the physical
domain via a materialList
attribute in the <ElementRegions>
block.
The following attributes are supported:
Name | Type | Default | Description |
---|---|---|---|
defaultReferencePorosity | real64 | required | Default value of the reference porosity |
grainBulkModulus | real64 | required | Grain bulk modulus |
name | string | required | A name is required for any non-unique nodes |
Example¶
<Constitutive>
...
<BiotPorosity name="rockPorosity"
grainBulkModulus="1.0e27"
defaultReferencePorosity="0.3"/>
...
</Constitutive>