SALOME documentation central

2D Meshing Hypotheses



Max Element Area

Max Element Area hypothesis is applied for meshing of 2D faces composing your geometrical object. Definition of this hypothesis consists of setting the maximum area of meshing elements (depending on the chosen meshing algorithm it can be triangles or quadrangles), which will compose the mesh of these 2D faces.

a-maxelarea.png


max_el_area.png

In this example, Max. element area is very small compared to the 1D hypothesis

See Also a sample TUI Script of a Maximum Element Area hypothesis operation.


Length from Edges

Length from edges hypothesis builds 2D mesh segments having a length calculated as an average edge length for a given wire.

See Also a sample TUI Script of a Length from Edges hypothesis operation.


Quadrangle parameters

Quadrangle parameters is a hypothesis for Quadrangle (Mapping), which allows using this algorithm for meshing of triangular faces.In this case it is necessary to select the Base vertex used as a degenerated edge.

hypo_quad_params_1.png

A face built from 3 edges

hypo_quad_params_res.png

The resulting mesh

This hypothesis can be also used to mesh a segment of a circular face. Please, consider that there is a limitation on the selectiion of the degenerated vertex for the faces built with the angle > 180 degrees (see the picture).

hypo_quad_params_2.png

3/4 of a circular face

In this case, selection of a wrong vertex for the Quadrangle parameters hypothesis will generate a wrong mesh. The picture below shows the good (left) and the bad (right) results of meshing.

hypo_quad_params_res_2.png

The resulting meshes


Quadrangle Preference

This algorithm can be used only together with Quadrangle (Mapping) algorithm. It allows to build quadrangular meshes even if the number of nodes at the opposite edges of a meshed face is not equal, otherwise this mesh will contain some triangular elements.
This hypothesis has one restriction on its work: the total quantity of segments on all four sides of the face must be even (divisible by 2).


Triangle Preference

This algorithm can be used only together with Quadrangle (Mapping) algorithm. It allows to build triangular mesh faces in the refinement area if the number of nodes at the opposite edges of a meshed face is not equal, otherwise refinement area will contain some quadrangular elements.


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