For the flow solvers computation, the materials in the structure and the fluids flowing through it need to be defined under the Constituent Materials tab, so that their physical properties parameters are taken into account.

The fluid flowing through all pore and porous materials can be set by clicking Set all Fluids to and selecting it from the pull-down menu.

If one of the predefined fluids (Air, Carbon Dioxide (CO2), Electrolyte (Solvionic), Electrolyte, Helium, Hydrogen, Mercury, Natural Gas, Nitrogen (N2), Oil, Oxygen or one of the three types of Water) is used, the values for Density, Dynamic Viscosity and Kinematic Viscosity are taken from the GeoDict Material Database. They are dependent on the given Temperature value and the Chosen Material Law. If Manual is selected, these values can be entered manually.

Any values entered manually, e.g., for a special type of oil, can also be added to the material database through the Open & Edit Material Database button. Additionally, different properties for the same material can be saved as different Material Laws and can then be selected from the pull-down menu in the Set all Fluids to dialog. Material Law 1 is the default shipped with GeoDict. Click here for more information on editing, expanding, and using the GeoDict Material Database.

The Temperature is selectable in Kelvin (K), Celsius (°C), and Fahrenheit (F), and has a default value of 293.15 K (20.0°C, 68 F).

Under the Material subtab, the fluid used for the simulation can be selected from the pull-down menu for Use. If other fluids are contained in the structure, they will be treated as solid materials during the simulation. If the structure contains no fluid material, No fluid in geometry is displayed in the top of the Material tab. Select a material for the pore phase by clicking on the material ID to be treated as fluid, as described below.

The density and the dynamic viscosity of this fluid, at the selected temperature range, is shown under the Fluid Density/Viscosity subtab.

Also, under the Material subtab, the material IDs assigned to the materials that are present in the structure model are shown (00, 01, 02, etc.). These material IDs, which fall into one of the material categories (Solid, Fluid, or Porous Solid), can be selected through the Material Selector dialog, by clicking on the material buttons.

Click the Material Report button to see the relevant parameters for the material with a selected ID.

Fluid flow can happen in pores and porous materials, but not in solid materials.

Next to the Material Report icon for all fluids and porous materials in the geometry a checkbox is displayed. The flow happens in all materials, where this checkbox is checked.

When the structure model is made up of solid, pore, and porous voxels, the SimpleFFT or the LIR solver must be chosen under the Solver tab, as described here. For the EJ solver an error message is shown after clicking Run (see here for more information).

Empty voxels are infinitely permeable. For all other structure voxels, the user must define whether they are solid or porous. Solid voxels are set as shown above.

For porous voxels, set the Material Type (in the Material Selector dialog) to Porous and choose the fluid that occupies the voxels.

The permeability of porous voxels is set under the Permeability subtab in the Solver Options dialog. Being permeable, it can be also defined whether the material displays isotropic or anisotropic orientation to the fluid flow.

When the material is isotropic, the permeability entered only for the X-direction is used for all directions, whereas for the anisotropic orientation of the material, the permeabilities in the three Cartesian directions are needed.

Currently, the local orientation of porous materials with anisotropic properties is not considered. The SimpleFFT solver must be chosen if anisotropic permeabilities are entered.