This node defines the material properties of the fluid of the Porous Medium parent node.

Specify the Density ρ and the Dynamic viscosity μ (SI unit: Pa·s) of the fluid. The defaults use values From material, for User defined enter a value or expression.

If the Polymer Flow Module license is available and for Darcian flow, also non-Newtonian models are available and the Constitutive Relation can be switched between Specify dynamic viscosity (default) or Inelastic non-Newtonian.

Use the default option to either get the dynamic viscosity from a material, or to add a user defined expression. The default option lets you either use the dynamic viscosity from a material or define it with a custom expression. The Inelastic non-Newtonian option provides several models and defines the Apparent shear rate.

The following inelastic non-Newtonian Models are available for the Fluid feature under the Porous Medium feature:

The setup of these models in porous media is similar to their definition under the Fluid Properties feature.

To define the apparent shear rate , either enter a user-defined expression for the correction factor (α) or choose the Capillary bundle approach from the list and provide a value for the Tortuosity factor (C).

A default Fluid node is automatically added to the Porous Medium node.