4.12. Internal surfaces

Internal surfaces are surfaces defined within the overall boundaries of the model.

To define an internal surface, there must be a region already defined in the Regions Pane.

4.12.1. Add/Delete Internal surfaces

To add an internal surface, navigate to the ISs pane from the Modeler View, and click the (+) button. A popup dialog will appear to select region(s) that will define the internal surface. Each region can only be used in a single internal surface.

All regions defined in the regions Pane are listed in the popup, but only the regions of the selected Surface Type are selectable.

  • Plane Regions can be Impermeable internal surfaces.

  • Box Regions can be X-Axis, Y-Axis, or Z-Axis Impermeable internal surfaces.

  • Plane Regions can be Semi-permeable internal surfaces.

  • Box Regions can be X-Axis, Y-Axis, or Z-Axis Semi-permeable internal surfaces.

To remove an internal surface, navigate to the ISs pane from the Modeler View, select the internal surface to remove, and click the (-) button.

4.12.2. Internal Surface Type

Planar internal surfaces can be of type:

  • Impermeable

  • Semi-Impermeable

Volumetric internal surfaces can be of type:

  • X-Axis Impermeable

  • Y-Axis Impermeable

  • Z-Axis Impermeable

  • X-Axis semi-permeable

  • Y-Axis semi-permeable

  • Z-Axis semi-permeable

4.12.3. Fluid permeability

The permeability is only definable for semipermeable regions. The default value is 1.0d32 m².

4.12.4. Internal resistance coefficient

The internal resistance is only definable for semipermeable regions. The default value is 0.0 m⁻¹.

4.12.5. Internal Surface Velocities

For each solid phase, specify the velocity of that solid through the surface (in meters/second).

Disabled for Impermeable surface (since by definition the velocity would be zero).