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 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.
Usage
- 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 region button.
- Select the Mesh object in the Model Tree and select the Mesh →
FEM mesh region option from the menu.
- Select the Mesh object in the Model Tree and press the
- Edit the maximum element size for the region.
- Click the OK button.
- Close the task.
- Result: You now should see a new
FEMMeshRegion
object under theFEMMeshGMSH
object (see example #3 below) in your active analysis container.
- Result: You now should see a new
- Double-click on the
FEMMeshGMSH
parent object in your Model Tree and press Apply to force a mesh recalculation. - 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
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)
- Materials: Solid, Fluid, Nonlinear mechanical, Reinforced (concrete); Material editor
- Element geometry: Beam (1D), Beam rotation (1D), Shell (2D), Fluid flow (1D)
Constraints
- Electromagnetic: Electrostatic potential, Current density, Magnetization
- 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
- 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
- Additional: Preferences; FEM Install, FEM Mesh, FEM Solver, FEM CalculiX, FEM Concrete; FEM Element Types
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