Boundary Layer Properties
Add a Boundary Layer Properties node () to specify the location of the boundary layers and the properties, such as the number of layers and thickness of the boundary layers.
By default, one Boundary Layer Properties node is added as a subnode to a Boundary Layers node. To add additional nodes, right-click a 2D or 3D Boundary Layers node and select Boundary Layers Properties; then enter the properties using the following sections:
Geometric Entity Selection
Define the edges (for faces in 3D) or boundaries where to add boundary layers. Choose Manual in the Selection list to select the entities in the Graphics window or choose All boundaries or All edges to select all boundaries or edges respectively.
Setting Geometric entity level: Domain or Boundary in the Boundary Layers node changes the name of this section to Boundary Selection or Edge Selection, respectively.
Layers
The default Number of layers is 8.
The default Stretching factor is 1.2. This field is used to specify the increase in thickness between two consecutive boundary layers as a scaling factor; for example, entering 1.3 means that the thickness increases by 30% from one layer to the next.
To specify the thickness of the boundary layer mesh, choose an option from the Thickness specification list: Automatic (the default), First layer, or All layers.
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If Automatic is kept, enter the Thickness adjustment factor (default is 1) to specify a scaling of the thickness of the first layer — the layer adjacent to the corresponding boundary.
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If First layer is selected, specify the Thickness of the first element layer.
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If All layers is selected, specify the Total thickness of the boundary layer mesh.
The default thickness of the first layer and the total thickness of the boundary layer mesh are both determined from the specified element size in the sequence.
The boundary layer meshing algorithm shrinks the boundary layers automatically if needed (for example, due to a narrow region); however, the stretching factor is always respected. In some cases the boundary layer meshing algorithm can choose to create fewer layers than specified. If this happens, a warning is printed to the Log page of The Progress Window.
Boundary Layers