Use Simulate Flow Experiment if the inlet and outlet are not axis-aligned in the same flow direction, for example if the flow enters and leaves a component through tubes. Define where the flow enters and leaves the structure by setting up one inlet and one or more outlets. Usually, the complete structure is encased by solid voxels except for the inlet and outlet voxels. For symmetric structures, it is also possible to model only one half or one quarter of the structure and use symmetric boundary conditions instead. The inlet and outlet are defined by certain material IDs.

The inlet and outlet materials must be defined in the structure with certain conditions:

• While they must have different material IDs, inlet and outlet should have the same material (i.e., fluid) as the pore space inside the structure.
• While several IDs can be defined as outlet, only one ID can be set to inlet.
• There can be several inlet and outlet areas. They can even be located at different sides of the structure.
• Since GeoDict 2024 inlet and outlet can be thicker than 1 voxel and do not need to be axis-aligned. Also, pore voxels at the boundary are allowed.
• Only one connected pore system is allowed.
  • It must contain all fluids and porous materials as well as inflow and outflow areas.
  • Inlet and outlet are not allowed to be connected via an outer fluid.