3 \page ghs3d_hypo_page GHS3D Parameters hypothesis
6 \n GHS3D Parameters hypothesis works only with <b>Tetrahedron (GHS3D)</b>
7 algorithm. This algorithm is a commercial software.
8 \n To get a licence, visit http://www.distene.com/corp/eval-distene.html
10 -# \ref ghs3d_general_parameters
11 -# \ref ghs3d_advanced_parameters
12 -# \ref ghs3d_enforced_vertices
13 -# \ref ghs3d_enforced_meshes
15 \section ghs3d_general_parameters General parameters
17 \image html ghs3d_parameters_basic.png
20 <li><b>Name</b> - allows to define the name of the hypothesis (GHS3D
21 Parameters by default).</li>
23 <li><b>To mesh holes</b> - if checked, the algorithm will
24 create mesh in the holes inside a solid shape, else only the outermost
25 shape will be meshed. Volumic elements created within holes are bound
28 <li><b>Optimization level</b> - allows choosing the required
33 <li>medium (standard),</li>
38 optimisation provides better mesh, but can be time-consuming.
42 \ref ghs3d_top "Back to top"
44 \section ghs3d_advanced_parameters Advanced parameters
46 \image html ghs3d_parameters_advanced.png
48 <li><b>Maximum memory size</b> - launches ghs3d software with
49 work space limited to the specified amount of RAM, in Mbytes. If this option is
50 checked off, the software will be launched with 7O% of the total RAM space. </li>
52 <li><b>Initial memory size</b> - starts ghs3d software with
53 the specified amount of work space, in Mbytes. If this option is checked off, the
54 software will be started with 100 Megabytes of working space. </li>
56 <li><b>Working directory</b> - allows defining the folder for input and output
57 files of ghs3d software, which are the files starting with "GHS3D_" prefix. </li>
59 <li><b>Keep working files</b> - allows checking input and output files
60 of ghs3d software, while usually these files are removed after the
61 launch of the mesher.</li>
63 <li><b>Verbose level</b> - to choose verbosity level in the range from
65 <ul> <li>0, no standard output,
66 </li><li>2, prints the data, quality statistics of the skin and final
67 meshes and indicates when the final mesh is being saved. In addition
68 the software gives indication regarding the CPU time.
69 </li><li>10, same as 2 plus the main steps in the computation, quality
70 statistics histogram of the skin mesh, quality statistics histogram
71 together with the characteristics of the final mesh.
74 <li><b>To create new nodes</b> - if this option is checked off, ghs3d
75 tries to create tetrahedrons using only the nodes of the 2D mesh.</li>
77 <li><b>To remove the initial central point</b> TetMesh-GHS3D adds an internal point
78 at the gravity centre of the bounding box to speed up and to simplify
79 the meshing process. However, it is possible to refrain from creating
80 this point by using the command line option -no initial central point. This can be
81 particularly useful to generate a volume mesh without internal points at all and in some rare cases
82 at the boundary regeneration phase when it is impossible to proceed
83 with the standard options
84 (for example, when one dimension of the domain is more than 20 times greater than the other two).
85 Use this option if the boundary regeneration has failed with the standard parameters and before using
86 the recovery version (command line option -C).
87 Note: when using this option, the speed of the meshing process may
88 decrease, and the quality may change.
89 Note: the boundary regeneration may fail with this option, in some rare cases.</li>
91 <li><b>To use boundary recovery version</b> - enables using a
92 boundary recovery module which tries to
93 create volume meshes starting from very poor quality surface meshes
94 (almost flat triangles on the surface, high density propagation,
95 extreme aspect ratios, etc.) which fails with the standard version. The
96 resulting volume mesh will however most likely have a very poor
97 quality (poor aspect ratio of elements, tetrahedra with a very small
98 positive volume).</li>
100 <li><b>To use FEM correction</b> - Applies finite-element correction by
101 replacing overconstrained elements where it is possible. At first the process
102 slices the overconstrained edges and at second the overconstrained
103 facets. This ensures that there are no edges with two boundary
104 vertices and that there are no facets with three boundary vertices. TetMesh-GHS3D gives the initial
105 and final overconstrained edges and facets. It also gives the facets
106 which have three edges on the boundary.
107 Note: when using this option, the speed of the meshing process may
108 decrease, quality may change, and the smallest volume may be smaller.
109 By default, the FEM correction is not used.</li>
111 <li><b>Option as text</b> - allows to input in the command line any text
112 for ghs3d, for example, advanced options. </li>
116 \ref ghs3d_top "Back to top"
118 \section ghs3d_enforced_vertices Enforced vertices
120 \note This feature is currently available only on meshes with no
121 geometry attached. Such meshes can be obtained by
123 <li>Copying an existing mesh</li>
124 <li>Importing a mesh from file</li>
125 <li>Applying a transformation to a mesh a get result in a new mesh</li>
128 \image html ghs3d_enforced_vertices.png
130 GHS3D algorithm can locally make the mesh finer. It is possible to
131 define enforced vertices in the volume where the mesh will be detailed.
132 A node will be created at the enforced vertex coordinates.
134 An enforced vertex is defined by:
138 <li>from GEOM (Vertex, Compound)</li>
139 <li>or from (x,y,z) cartesian coordinates</li>
141 <li>A constant physical size</li>
142 <li>If a group name is given, the created node will be added to the
143 group. If the group does not exist, it is created.</li>
145 \ref ghs3d_top "Back to top"
147 \section ghs3d_enforced_meshes Enforced Meshes
149 \note This feature is currently only available on 2D meshes with no
150 geometry attached. Such meshes can be obtained by
152 <li>Copying an existing 2D mesh</li>
153 <li>Importing a 2D mesh from file</li>
154 <li>Applying a transformation to a 2D mesh a get result in a new mesh</li>
157 \image html ghs3d_enforced_meshes.png
159 GHS3D algorithm can be forced by other meshes, sub-meshes or
160 groups. The constraint elements should be contained
161 entirely into the solid mesh.
163 <li>The constraint element types are:
169 <li>If a size is given, the mesh will be refined around the enforced
170 elements given the size (not available yet)</li>
171 <li>If a group name is given, the enforced elements will be added to
172 the group. If the group does not exist, it is created.</li>
175 <br><b>See Also</b> a sample TUI Script of the \ref tui_ghs3d "creation of a Ghs3D hypothesis", including enforced vertices and meshes.
177 \ref ghs3d_top "Back to top"