FEM MeshRegion

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FEM MeshRegion.svg FEM MeshRegion

Menu location
Mesh → FEM mesh region
Workbenches
FEM
Default shortcut
None
Introduced in version
-
See also
FEM tutorial

Description

FEM MeshRegion 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 stronger gradient of a variable. For example, it can be used to refine the mesh around stress-risers (sharp edges, circles...) 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.

Usage

  1. To enable the function a mesh must be first provided FEM MeshGmshFromShape.svg FEM mesh from shape by Gmsh.
    • Select the Mesh object in the Model Tree and press the FEM MeshRegion.svg button.
    • Select the Mesh object in the Model Tree and select the Mesh → FEM MeshRegion.svg FEM mesh region option from the menu.
  2. Edit the maximal 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 crated you can change its properties using the property editor. After you changed 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

FEMMeshRegion Example1.png

Example 1: The initial coarse FEMMeshGMSH


FEMMeshRegion Example2.png

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

FEMMeshRegion Example3.png

Example 3: A simple example of the resulting Model Tree

Notes

The order in which the regions are shown in Tree view could change the mesh result. See this forum thread.

Related

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