Boundary Layer Properties
Add a Boundary Layer Properties node () to specify the location of the boundary layers and the properties, such as the number 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 Mesh node and select Boundary Layers Properties; then enter the properties using the following sections:
Boundaries
Define the boundaries where you want boundary layers. Choose Manual in the Selection list to select the boundaries in the Graphics window or choose All boundaries to select all boundaries.
Boundary Layer Properties
The default Number of boundary layers is 8.
The default Boundary layer 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 first element layer — the layer adjacent to the corresponding boundary — choose an option from the Thickness of first layer list: Automatic (the default) or Manual.
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If Automatic is kept as the default, the thickness of the first layer is 1/20 of the local domain element height. Enter the Thickness adjustment factor to specify a scaling factor that multiplies this default size. The default is 1.
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If Manual is selected, the default Thickness (SI unit: m)) is 0.00118 m.
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.