FEM MeshRegion

FEM mesh boundary layer

FEM mesh group

FEM

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 mesh from shape by Gmsh.
   • Select the Mesh object in the Model Tree and press the button.
   • Select the Mesh object in the Model Tree and select the Mesh → 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. You now should see a new FEMMeshRegion object under the FEMMeshGMSH object 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

Example 1: The initial coarse FEMMeshGMSH

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

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)

FEM mesh boundary layer

FEM mesh group

FEM

FEM

• FEM Analysis

• Materials: Solid, Fluid, Nonlinear mechanical, Reinforced (concrete); Material editor

• Element geometry: Beam (1D), Beam rotation (1D), Shell (2D), Fluid flow (1D)

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Constraints

• Electromagnetic: Electrostatic potential, Current density, Magnetization

• Fluid: Initial flow velocity, Initial pressure, Flow velocity

• Geometrical: Plane rotation, Section print, Transform

• Mechanical: Fixed, Displacement, Contact, Tie, Spring, Force, Pressure, Centrif, Self weight

• Thermal: Initial temperature, Heat flux, Temperature, Body heat source

• Overwrite Constants: Constant vacuum permittivity

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• Mesh: Mesh Netgen, Mesh GMSH, Mesh boundary layer, Mesh region, Mesh group, Nodes set, Mesh to mesh

• Solve: CalculiX Standard, Elmer, Mystran, Z88; Equations: Deformation, Elasticity, Electrostatic, Electricforce, Magnetodynamic, Magnetodynamic 2D, Flow, Flux, Heat; Solver: Solver control, Solver run

• Results: Purge, Show; Postprocessing: Apply changes, Pipeline from result, Warp filter, Scalar clip filter, Function cut filter, Region clip filter, Contours filter, Line clip filter, Stress linearization plot, Data at point clip filter, Filter function plane, Filter function sphere, Filter function cylinder, Filter function box

• Utilities: Clipping plane, Remove clipping planes, Open FEM examples; Mesh clear, Mesh display info

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• Additional: Preferences; FEM Install, FEM Mesh, FEM Solver, FEM CalculiX, FEM Concrete; FEM Element Types

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• Installation: Download, Windows, Linux, Mac, Additional components, Docker, AppImage, Ubuntu Snap
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