doc/salome/gui/SMESH/files/about_meshing_algorithms.htm

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 111 </script>
 112 <h1>Basic meshing algorithms</h1>
 113
 114 <p><img src="../i_blue.jpg" x-maintain-ratio="TRUE" width="30px" height="30px" border="0" class="img_whs1"> The MESH module contains a set of meshing algorithms,
 115  which are used for meshing entities (1D, 2D, 3D) composing geometrical
 116  objects. </p>
 117
 118 <p>&nbsp;</p>
 119
 120 <ul type="disc" class="whs2">
 121
 122         <li class=kadov-p><p>For meshing of 1D entities (<span style="font-weight: bold;"><B>edges</B></span>):</p></li>
 123 </ul>
 124
 125 <p>&nbsp;</p>
 126
 127 <ol type="disc" class="whs3">
 128
 129         <ul type="disc" class="whs2">
 130
 131                 <li style="list-style: circle;"
 132                         type=circle
 133                         class=kadov-p><p>Wire Discretisation meshing algorithm - splits
 134  a wire into a number of mesh segments following any 1D hypothesis.</p></li>
 135
 136                 <li style="list-style: circle;"
 137                         type=circle
 138                         class=kadov-p><p>Composite Side Discretisation algorithm -
 139  allows to apply any 1D hypothesis to a whole side of a geometrical face
 140  even if it is composed of several edges provided that they form C1 curve,
 141  have the same hypotheses assigned and form one side in all faces of the
 142  main shape of a mesh.</p></li>
 143         </ul>
 144 </ol>
 145
 146 <p>&nbsp;</p>
 147
 148 <ul type="disc" class="whs2">
 149
 150         <li class=kadov-p><p>For meshing of 2D entities (<span style="font-weight: bold;"><B>faces</B></span>):</p></li>
 151 </ul>
 152
 153 <p>&nbsp;</p>
 154
 155 <ol type="disc" class="whs3">
 156
 157         <ul type="circle" class="whs4">
 158
 159                 <li class=kadov-p><p>Triangle meshing algorithms (Mefisto and Netgen
 160  1D-2D ) - Faces are split into triangular elements.</p></li>
 161
 162                 <li class=kadov-p><p>Quadrangle meshing algorithm (Mapping) - Faces
 163  are split into quadrangular elements.</p></li>
 164         </ul>
 165 </ol>
 166
 167 <p>&nbsp;</p>
 168
 169 <table x-use-null-cells cellspacing="0" width="45.771%" class="whs5">
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 174 <td width="42.826%" class="whs9">
 175 <p class="whs10"><img src="../image123.gif" width="170px" height="170px" border="0" class="img_whs11"></td>
 176 <td width="57.174%" class="whs12">
 177 <p class="whs13"><img src="../image124.gif" width="182px" height="177px" border="0" class="img_whs14"></td></tr>
 178 </table>
 179
 180 <p>&nbsp;</p>
 181
 182 <p>&nbsp;</p>
 183
 184 <ul type="disc" class="whs2">
 185
 186         <li class=kadov-p><p>For meshing of 3D entities (<span style="font-weight: bold;"><B>volume
 187  objects</B></span>):</p></li>
 188 </ul>
 189
 190 <p>&nbsp;</p>
 191
 192 <ol type="disc" class="whs3">
 193
 194         <ul type="circle" class="whs4">
 195
 196                 <li class=kadov-p><p>Hexahedron meshing algorithm (i,j,k) - Volumes
 197  are split into hexahedral (cubic) elements. </p></li>
 198
 199                 <li class=kadov-p><p>Tetrahedron (Netgen) meshing algorithm - Volumes
 200  are split into tetrahedral (pyramidal) elements. </p></li>
 201         </ul>
 202 </ol>
 203
 204 <p>&nbsp;</p>
 205
 206 <table x-use-null-cells cellspacing="0" width="30.595%" class="whs15">
 207 <col class="whs16">
 208 <col class="whs17">
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 210 <tr valign="top" class="whs8">
 211 <td width="50.334%" class="whs18">
 212 <p><img src="../image125.gif" width="119px" height="299px" border="0" class="img_whs19"> </td>
 213 <td width="49.666%" class="whs20">
 214 <p><img src="../image126.gif" width="127px" height="298px" border="0" class="img_whs21"></td></tr>
 215 </table>
 216
 217 <p>&nbsp;</p>
 218
 219 <p>&nbsp;</p>
 220
 221 <p>There also is a number of more specific algorithms: </p>
 222
 223 <ul type="disc" class="whs2">
 224
 225         <li class=kadov-p><p><a href="../projection_algorithms.htm">for meshing
 226  by projection of another mesh</a></p></li>
 227
 228         <li class=kadov-p><p><a href="../radial_prism.htm">for meshing geometrical
 229  objects with cavities</a></p></li>
 230
 231         <li class=kadov-p><p><a href="../prism_3d_algorithm.htm">for meshing
 232  prismatic shapes.</a> </p></li>
 233 </ul>
 234
 235 <h4 class="whs22"><a href="constructing_meshes.htm">Constructing
 236  meshes</a> <span style="font-weight: normal;">page describes in detail
 237  how to apply meshing algorithms.</span><a href="constructing_meshes.htm" style="font-weight: bold;">
 238  </a></h4>
 239
 240 <p class="whs23"><span style="font-weight: bold;"><B>See Also</B></span>
 241  a sample TUI Script of a <a href="../defining_hypotheses_tui.htm#bookmark8">Define
 242  Meshing Algorithm</a> operation. &nbsp;</p>
 243
 244 <p>&nbsp;</p>
 245
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