meshing 2D objects).
\image html netgen2d3d.png
-<center><em>Dialog boxes of <b>Netgen 1D-2D</b> and <b>Netgen
-1D-2D-3D</b> algorithms </em></center>
+<center><em>Hypothesis dialog boxes of <b>Netgen 1D-2D</b> and <b>Netgen
+ 1D-2D-3D</b> algorithms are same</em></center>
<br>
\image html netgen2d3d_only.png
<center><em>Dialog boxes of <b>Netgen 2D</b> and <b>Netgen 3D</b>
-algorithms </em></center>
+ algorithms </em></center>
- <b>Name</b> - allows to define the name for the algorithm (Netgen
2D (or 3D) Parameters by default).
- <b>Min Size</b> - minimum linear dimensions for mesh cells. It is
ignored if it is more than <b>Max Size</b>.
- <b>Second Order</b> - if this box is checked in, the algorithm will
-create second order nodes on the mesh, which actually will become
-\ref adding_quadratic_elements_page "Quadratic".
-- <b>Fineness</b> - ranging from Very Coarse to Very Fine allows to set the
-level of meshing detalization using the three parameters below. You
-can select Custom to define them manually.
+create second order mesh.
+- <b>Fineness</b> - ranging from <em>Very Coarse</em> to <em>Very Fine</em>
+allows to set the level of meshing detalization using the three
+parameters below. You can select \a Custom to define them manually.
- <b>Growth rate</b> - allows to define how much the linear dimensions of
-two adjacent cells can differ (i.e. 0.3 means 30%).
-- <b>Nb. Segs per Edge</b> and <b>Nb Segs per Radius</b> - allows to define the
-minimum number of mesh segments in which edges and radiuses will be
-split.
-- <b>Allow Quadrangles</b> - allows to use quadrangle elements in a
-triangle 2D mesh. This checkbox is not present in Netgen 3D parameters
-because currently building a tetrahedral mesh with quadrangle faces is
-not possible.
-- <b>Optimize</b> - if this box is checked in, the algorithm will try to
-create regular (possessing even sides) elements.
+two adjacent cells can differ (e.g. 0.3 means 30%).
+- <b>Nb. Segs per Edge</b> - allows to define the minimum number of
+mesh segments in which edges will be split. This parameter is used
+only if <b>Limit Size by Surface Curvature</b> is checked.
+- <b>Nb Segs per Radius</b> - allows to define the size of
+mesh segments and mesh faces in which curved edges and surfaces will
+be split. This value divided by a radius of curvature gives an element
+size at a given point. This parameter is used only if <b>Limit Size by
+ Surface Curvature</b> is checked.
+- <b>Limit Size by Surface Curvature</b> - if this box is checked in,
+then size of mesh segments and mesh faces on curved edges and surfaces
+is defined using value of <b>Nb Segs per Radius</b> parameter, and
+number of segments on straight edges is defined by values of
+<b>Nb. Segs per Edge</b> parameter. If this box is not checked in,
+then size of elements is defined by three parameters only:
+<b>Max Size</b>, <b>Min Size</b> and <b>Growth rate</b>.
+- <b>Allow Quadrangles</b> - if this box is checked in, the mesher
+tries to generate quadrangle 2D mesh. Triangle elements are created
+where quadrangles are not possible.
+- <b>Optimize</b> - if this box is checked in, the algorithm will modify
+initially created mesh in order to improve quality of elements. Optimization
+process is rather time consuming comparing to creation of initial mesh.
+- <b>Fuse Coincident Nodes on Edges and Vertices</b> - allows merging
+mesh nodes on vertices and edges which are geometrically coincident
+but are topologically different.
\image html netgen3d_local_size.png
dimension.
\b 1D group allows defining the size of 1D elements in either of two ways:
-- <b>Number of Segments</b> has the same sense as \ref
-number_of_segments_anchor "Number of segments" hypothesis with
-equidistant distribution.
-- <b>Local Length</b> has the same sense as \ref
-average_length_anchor "Local Length" hypothesis.
+- <b>Number of Segments</b> allows specifying number of segments, that
+will split each edge, with equidistant distribution.
+- <b>Local Length</b> defines length of segments.
\b 2D group allows defining the size of 2D elements
-- <b>Length from edges</b> if checked in, acts like \ref
-length_from_edges_anchor "Length from Edges" hypothesis, else
-- <b>Max. Element Area</b> defines the maximum element area like \ref
-max_element_area_anchor "Max Element Area" hypothesis.
-- <b>Allow Quadrangles</b> - allows to use quadrangle elements in a
-triangle 2D mesh. This checkbox is not present in Netgen 3D simple parameters
-because currently building a tetrahedral mesh with quadrangle faces is
-not possible.
+- <b>Length from edges</b> if checked in, size of
+2D mesh elements is defined as an average mesh segment length
+for a given wire, else
+- <b>Max. Element Area</b> specifies expected maximum element area for
+each 2d element.
+- <b>Allow Quadrangles</b> - allows to generate quadrangle elements
+wherever possible.
\b 3D groups allows defining the size of 3D elements.
- <b>Length from faces</b> if checked in, the area of sides of
volumic elements will be equal to an average area of 2D elements, else
-- <b>Max. Element Volume</b> defines the maximum element volume like
-\ref max_element_volume_hypo_page "Max Element Volume"
-hypothesis.
+- <b>Max. Element Volume</b> specifies expected maximum element volume
+of 3d elements.
\note Netgen algorithm does not strictly follow the input
parameters. The actual mesh can be more or less dense than
required. There are several factors in it:
-- NETGEN does not actually use "NbOfSegments" parameter for discretization of
-edge. This parameter is used only to define the local element size
-(size at the given point), so local sizes of adjacent edges influence
-each other.
+- NETGEN does not actually use <b>Number of Segments</b> parameter for
+discretization of edge. This parameter is used only to define the
+local element size (size at the given point), so local sizes of
+close edges influence each other.
- NETGEN additionally restricts the element size according to edge curvature.
-- The local size of edges influences the size of close triangles.
+- The local size of segments influences the size of close triangles.
- The order of elements and their size in the 1D mesh generated by
NETGEN differ from those in the 1D mesh generated by Regular_1D
algorithm, resulting in different 2D and 3D meshes.
*/
-
-
