FEM MeshBoundaryLayer

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FEM MeshBoundaryLayer.svg FEM MeshBoundaryLayer

Menu location
Mesh → FEM mesh boundary layer
Default shortcut
Introduced in version
See also
FEM tutorial


FEM MeshBoundaryLayer 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 close to edges or surfaces in flow simulations. For example, it can be used to refine the mesh in the vicinity of an air foil or obstacle in a flow.

The boundary layer has the advantage of creating highly defined, anisotropic meshes. As the name implies it supports accurate calculations near boundaries, e.g. a wall where friction occurs, generating a velocity gradient.


  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 MeshBoundaryLayer.svg button.
    • Select the Mesh object in the Model Tree and select the Mesh → FEM MeshBoundaryLayer.svg FEM mesh boundary layer option from the menu.
  2. Edit the start element size, the growth rate and the number of growth layers.
  3. Select a vertex, edge, face.
  4. Click the OK button.
  5. Close the task.
    Result: You now should see a new FEMMeshBoundaryLayer object under the FEMMeshGMSH object (see example #3 below) in your active analysis container.
  6. Double-click on the FEMMeshGMSH parent object in your Model Tree and press Apply to force a mesh recalculation.
  7. 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 boundary layers as needed.

Visual examples

FEMMeshBoundaryLayer Example1.png.png

Example 1: The initial coarse FEMMeshGMSH on a 2D case

FEMMeshBoundaryLayer Example2.png.png

Example 2: After applying a Mesh boundary layer

FEMMeshBoundaryLayer Example3.png.png

Example 3: A simple example of the resulting Model Tree