<h2>Quadratic Mesh</h2>
Quadratic Mesh hypothesis allows to build a quadratic mesh (whose
-edges are not straight but broken lines and can be defined by three
-points: first, middle and last) instead of an ordinary one.
+edges are not straight but curved lines and can be defined by three
+points: first, middle and last instead of an ordinary two).
+
+See \ref adding_quadratic_elements_page
+for more information about quadratic meshes.
\anchor propagation_anchor
<h2>Propagation of 1D Hypothesis on opposite edges</h2>
<br><b>See Also</b> a sample TUI Script of a
\ref tui_propagation "Propagation hypothesis" operation
+\anchor propagofdistribution_anchor
+<h2>Propagation of Node Distribution on Opposite Edges</h2>
+
+<b>Propagation of Node Distribution on Opposite Edges</b> allows to propagate
+distribution of nodes onto an opposite edge. If a local hypothesis and
+propagation are defined on an edge of a quadrangular face, the
+opposite edge will have the same number of nodes and the same
+relations between segment lengths, unless another hypothesis
+has been locally defined on the opposite edge.
+
+<br><b>See Also</b> a sample TUI Script of a
+\ref tui_propagation "Propagation hypothesis" operation
+
\anchor quadrangle_preference_anchor
<h2>Quadrangle Preference</h2>
segments on all four sides of the face must be even (divisible by 2).
\anchor viscous_layers_anchor
-<h2>Viscous Layers</h2>
-
-<b>Viscous Layers</b> additional hypothesis can be used together with
-some 3D algorithms, Hexahedron(i,j,k) for example. This
-hypothesis allows creation of layers of highly stretched prisms near
-mesh boundary, which is beneficial for high quality viscous
-computations. The prisms constructed on the quadrangular mesh faces are
-actually the hexahedrons.
+<h2>Viscous Layers and Viscous Layers 2D</h2>
+<b>Viscous Layers</b> and <b>Viscous Layers 2D </b> additional
+hypotheses can be used together with either some 3D algorithms, for example
+Hexahedron(i,j,k), or 2D algorithms, for example Triangle
+(MEFISTO), correspondingly. These hypotheses allow creation of layers
+of highly stretched elements, prisms in 3D and quadrilaterals in 2D,
+near mesh boundary, which is beneficial for high quality viscous
+computations.
\image html viscous_layers_hyp.png
<ul>
<li><b>Name</b> - allows to define the name of the hypothesis.</li>
-<li><b>Total thicknes</b> - gives the total thickness of prism layers.</li>
-<li><b>Number of layers</b> - defines the number of prism layers.</li>
-<li><b>Stretch factor</b> - defines the growth factor of prism height
-from the mesh boundary inwards.</li>
-<li><b>Faces without layers</b> - defines geometrical faces on which
-prism layers should not be constructed. By default the prism layers
-are not constructed on geometrical faces shared by solids.</li>
+<li><b>Total thickness</b> - gives the total thickness of element layers.</li>
+<li><b>Number of layers</b> - defines the number of element layers.</li>
+<li><b>Stretch factor</b> - defines the growth factor of element height
+ from the mesh boundary inwards.</li>
+<li><b>Specified Faces/Edges are</b> - defines how the shapes specified by
+ the next parameter are used.
+<li><b> Faces/Edges with/without layers</b> -
+ defines geometrical faces or edges on which element layers
+ either should be or should not be constructed, depending on the
+ value of the previous parameter (<b>Specified Faces/Edges are</b>).
+ Faces (or edges) can be selected either in the Object Browser or in
+ the VTK Viewer.
+ \note A mesh shown in the 3D Viewer can prevent selection of faces
+ and edges, just hide the mesh to avoid this. To avoid a long wait when a
+ geometry with many faces (or edges) is displayed, the number of faces
+ (edges) shown at a time is limited by the value of "Sub-shapes
+ preview chunk size" preference (in Preferences/Mesh/General tab).<br>
+
+ If faces/edges without layers are specified, 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,
+ in this mode the element layers can be constructed on boundary faces
+ and edges only, and are not constructed on internal faces and
+ edges. There is an exception to this rule: if a hypothesis is
+ assigned to a sub-mesh, the element layers can be constructed on
+ boundary faces/edges of the shape of this sub-mesh, at same time
+ possibly being internal faces/edges within the whole model.
+ \image html viscous_layers_on_submesh.png 2D viscous layers constructed on boundary edges of a sub-mesh on a disk face.
+
+</li>
</ul>
\image html viscous_layers_mesh.png A group containing viscous layer prisms.
<br><b>See also</b> a sample TUI script of a \ref tui_viscous_layers
"Viscous layers construction".
-
*/
