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Netgen 2D and 3D hypotheses

Netgen 2D and Netgen 3D hypotheses work only with Netgen 1D-2D and Netgen 1D-2D-3D algorithms. These algorithms do not require definition of lower-level hypotheses and algorithms (2D and 1D for meshing 3D objects and 1D for meshing 2D objects). They prove to be useful if lower-level meshing is homogeneous for all wires and faces of the meshed object.

netgen2d.png
netgen3d_simple.png

Netgen 2D simple parameters and Netgen 3D simple parameters allow defining the size of elements for each dimension.

1D group allows defining the size of 1D elements in either of two ways:

2D group allows defining the size of 2D elements

3D groups allows defining the size 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 additionally restricts the element size according to edge curvature.
  • The local size of edges 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.

Copyright © 2007-2008 CEA/DEN, EDF R&D, OPEN CASCADE
Copyright © 2003-2007 OPEN CASCADE, EADS/CCR, LIP6, CEA/DEN, CEDRAT, EDF R&D, LEG, PRINCIPIA R&D, BUREAU VERITAS