4. Model guide

• 4.1. Model setup
• 4.2. Geometry
• 4.3. Mesh
• 4.4. Regions
• 4.5. Fluid
• 4.6. Solids
• 4.7. Scalars
• 4.8. Initial conditions
• 4.9. Boundary conditions
• 4.10. Point sources
• 4.11. Monitors
• 4.12. Internal surfaces
• 4.13. Keyframes
• 4.14. Chemistry

There are two workflows available to setup and run simulations:

1. The standard workflow lets users set up the entire simulation parameters (including the mesh parameters) before running the simulation. The mesh is generated at run time and therefore cannot be inspected before the simulation starts. This is the default workflow (available since the first GUI release in MFiX 17.1). This can sometimes lead to the utilization of a poor mesh and loss of productivity.

   The entire standard workflow is performed in the Modeler tab, which contains the following panes (panes are ordered in a logical progression):

• Modeler Tab

  • Model setup defines the overall solver type (Single-phase, TFM, DEM).

  • Geometry defines the overall physical space for the model.

  • Regions defines geometrical surfaces and volumes within the overall domain that are used in specifying boundary conditions, initial conditions, point sources, internal surfaces, outputs and monitors.

  • Mesh defines the spatial discretization.

  • Fluid defines fluid model options and physical properties.

  • Solids defines solids model options and physical properties.

  • Scalars defines scalar arrays different phases in the model.

  • Initial conditions defines the model initial conditions.

  • Boundary conditions defines the model boundary conditions.

  • Point sources defines point sources for the model.

  • Internal surfaces defines internal surfaces for the model.

  • Keyframes defines keyframe data for the model.

  • Chemical Reactions defines chemical reactions for the model.

2. The SMS (Segregated Mesh/Solver) workflow allows to generate and inspect the mesh before other model settings are specified. This can help identify poor meshes before run time. The mesh is saved into a .msh file and it will be read at run time by the solver. Other output files ([RUN_NAME]_boundary.vtk, [RUN_NAME]_MESH.vtu, MESH_STATS.txt) are generated to visualize the mesh and gather mesh statistics. The SMS workflow is currently (20.1 release) available as a beta feature and can be activated in the Settings menu.

   Please see SMS meshing workflow, cyclone, Discrete Element Model (DEM) for a tutorial showing how to use the SMS workflow.

• Mesher Tab

  The mesh generation is performed in the Mesher tab, which contains the following panes (panes are ordered in a logical progression):

  • Geometry defines the overall physical space for the model.

  • Regions defines regions that are used in boundary conditions.

  • Mesh defines the spatial discretization. The mesh is generated by clicking the Generate button. After inspection, a valid mesh must be accepted by clicking on the Accept button. This will unlock the Modeler tab.

• Modeler Tab

  • Model setup defines the overall solver type (Single-phase, TFM, DEM).

  • Regions defines geometrical surfaces and volumes within the overall domain that are used in specifying initial conditions, point sources, internal surfaces, outputs and monitors.

  • Fluid defines fluid model options and physical properties.

  • Solids defines solids model options and physical properties.

  • Scalars defines scalar arrays different phases in the model.

  • Initial conditions defines the model initial conditions.

  • Boundary conditions defines the model boundary conditions.

  • Point sources defines point sources for the model.

  • Internal surfaces defines internal surfaces for the model.

  • Keyframes defines keyframe data for the model.

  • Chemical Reactions defines chemical reactions for the model.

Note

Selections on panes may enable or disable widgets based on what input parameters are required or available.