+ preview chunk size" preference (in Preferences/Mesh/General tab).<br>
+
+ Whatever shapes are specified by this
+ parameter, the element layers are not constructed on geometrical
+ faces shared by several solids in 3D case and edges shared by
+ several faces in 2D case. In other words the element layers can be
+ constructed on boundary faces and edges, and are not constructed on
+ internal faces and edges. There is an exception to this rule in 2D
+ case: if "Viscous Layers 2D" hypothesis is assigned to a sub-mesh,
+ the element layers can be constructed on boundary edges of the shape
+ of this sub-mesh.
+ \image html viscous_layers_on_submesh.png 2D viscous layers constructed on boundary edges of a sub-mesh on a disk face.
+