FEM: Regione di mesh FEM

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FEM MeshRegion

Posizione nel menu
Mesh → FEM Mesh region
Ambiente
FEM
Avvio veloce
Nessuno
Introdotto nella versione
-
Vedere anche
Tutorial FEM

Descrizione

Enables the user to set a localized set of meshing parameters by selecting a set of elements (vertex, edge, face) and applying the parameters to it. It is especially useful for refining meshes in areas of interest or areas where the solver will generate a stronger gradient of a variable. For example, it can be used to refine the mesh around stress-risers (sharp edges, holes, notches, ...) in mechanical analysis, or at areas of contraction in a fluid flow.

Refining the mesh has the advantage of enabling accurate simulation where needed, while allowing coarser mesh in the wider domain, thus drastically optimizing the computation time while maintaining meaningful solutions output.

Utilizzo

  1. To enable the function a mesh must be first provided FEM mesh from shape by Gmsh.
    • Select the Mesh object in the Model Tree and press the FEM mesh refinement button.
    • Select the Mesh object in the Model Tree and select the Mesh → FEM mesh refinement option from the menu.
  2. Edit the maximum element size for the region.
  3. Click the OK button.
  4. Close the task.
    Result: You now should see a new FEMMeshRegion object under the FEMMeshGMSH object (see example #3 below) in your active analysis container.
  5. Double-click on the FEMMeshGMSH parent object in your Model Tree and press Apply to force a mesh recalculation.
  6. Close the task.

After the mesh has been created, you can change its properties using the property editor. After you change a property, you must reopen the Gmsh dialog again and click the Apply button (you can leave the dialog open while changing properties).

You can create as many different mesh regions as needed.

Visual examples

Example 1: The initial coarse FEM Mesh by GMSH


Example 2: After applying a Mesh refinement using two FEM Mesh Region objects, the large hole is refined to a maximum element size of 3 mm, the smaller hole is refined to 1 mm

Example 3: A simple example of the resulting Model Tree

Note

L'ordine in cui le regioni sono mostrate nella vista ad albero potrebbe cambiare il risultato della mesh. Vedere questa discussione nel forum.

Related

  • "Mesh Regions for a Better Analysis" - Video Tutorial by Joko Engineering (link)