FEM MeshRegion

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 [[Image:FEM_MeshGmshFromShape.svg|32px]] FEM mesh from shape by Gmsh.
 * 2) * Select the Mesh object in the Model Tree and press the [[Image:FEM_MeshRegion.svg|32px]] button.
 * 3) * Select the Mesh object in the Model Tree and select the option from the menu.
 * 4) Edit the maximal element size for the region.
 * 5) Click the  button.
 * 6) Close the task. You now should see a new FEMMeshRegion object under the FEMMeshGMSH object in your active analysis container.
 * 7) Double-click on the FEMMeshGMSH parent object in your Model Tree and press  to force a mesh recalculation.
 * 8) 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 button. (You can leave the dialog open while changing properties.)

You can create as many different mesh regions as needed.

Visual examples
The initial coarse FEMMeshGMSH

Example of 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.

A simple example of the resulting Model Tree