From 0a56ccc761f21470f6166b5b3892c65a6af02c91 Mon Sep 17 00:00:00 2001 From: eap Date: Wed, 6 Mar 2013 11:20:41 +0000 Subject: [PATCH] 0021859: SMESH : Add conversion from QUAD8 to QUAD9 and from HEXA20 to HEXA27 --- .../SMESH/input/adding_quadratic_elements.doc | 20 ++++++++++--- .../gui/SMESH/input/additional_hypo.doc | 3 ++ .../input/convert_to_from_quadratic_mesh.doc | 28 +++++++++++-------- 3 files changed, 35 insertions(+), 16 deletions(-) diff --git a/doc/salome/gui/SMESH/input/adding_quadratic_elements.doc b/doc/salome/gui/SMESH/input/adding_quadratic_elements.doc index 921948630..7f2cf5cf9 100644 --- a/doc/salome/gui/SMESH/input/adding_quadratic_elements.doc +++ b/doc/salome/gui/SMESH/input/adding_quadratic_elements.doc @@ -4,10 +4,22 @@ \n MESH module allows you to work with Quadratic Elements. -Quadratic Edge is not a straight but a broken line and can be defined -by three points: first, middle and last. All more complex \b Quadratic -\b Elements differ from ordinary ones in that they consist of Quadratic -Edges. +Quadratic elements are defined by same corner nodes as the +corresponding linear ones, and in addition they bear \a midside nodes +located between the corner nodes on element sides. + +The quadratic quadrilateral element can bear an additional node at the +element center, then it is referred as bi-quadratic one (or +QUAD9). The quadratic hexahedral element can bear 7 additional nodes: +at the element center and at centers of sides, then it is referred as +tri-quadratic one (or HEXA27). + +There are several ways you can create quadratic elements in your mesh: +- manually create quadratic elements (the way described below); +- use \ref quadratic_mesh_anchor "Quadratic Mesh" hypothesis to +generate quadratic mesh on your geometry; +- convert an existing linear mesh to a quadratic one +(see \ref convert_to_from_quadratic_mesh_page). To add a quadratic element to your mesh:
    diff --git a/doc/salome/gui/SMESH/input/additional_hypo.doc b/doc/salome/gui/SMESH/input/additional_hypo.doc index 2fde9c142..98353ed25 100644 --- a/doc/salome/gui/SMESH/input/additional_hypo.doc +++ b/doc/salome/gui/SMESH/input/additional_hypo.doc @@ -23,6 +23,9 @@ Quadratic Mesh hypothesis allows to build a quadratic mesh (whose edges are not straight but curved lines and can be defined by three points: first, middle and last instead of an ordinary two). +See \ref adding_quadratic_elements_page +for more information about quadratic meshes. + \anchor propagation_anchor

    Propagation of 1D Hypothesis on opposite edges

    diff --git a/doc/salome/gui/SMESH/input/convert_to_from_quadratic_mesh.doc b/doc/salome/gui/SMESH/input/convert_to_from_quadratic_mesh.doc index 81c164aa9..15fe1b750 100644 --- a/doc/salome/gui/SMESH/input/convert_to_from_quadratic_mesh.doc +++ b/doc/salome/gui/SMESH/input/convert_to_from_quadratic_mesh.doc @@ -3,13 +3,13 @@ \page convert_to_from_quadratic_mesh_page Convert to/from Quadratic Mesh \n This functionality allows transforming linear meshes (or -sub-meshes) to quadratic (or bi-quadratic) and vice versa. -See \ref adding_quadratic_elements_page "Adding quadratic elements" -for more information about quadratic meshes. -Note that conversion of a sub-mesh most probably will -produce a non-conformal mesh. Elements on the boundary between -quadratic (or bi-quadratic) and linear sub-meshes become (or remain) -quadratic (or bi-quadratic). +sub-meshes) to quadratic and vice versa. +Note that conversion of a sub-mesh most probably will produce a +non-conformal mesh. Elements on the boundary between quadratic and +linear sub-meshes become (or remain) quadratic. + +See \ref adding_quadratic_elements_page for more information about +quadratic meshes. To produce a conversion:
      @@ -19,8 +19,10 @@ Viewer. Mesh item , or click "Convert to/from quadratic" button in the toolbar. +
      \image html image154.png -
      "Convert to/from quadratic" button
      +"Convert to/from quadratic" button +
      The following dialog box will appear: @@ -31,10 +33,12 @@ The following dialog box will appear:
      • If it is necessary to convert a linear mesh to quadratic or a quadratic -mesh to linear. Note that the choice is available only if the selected mesh -(or sub-mesh) contains both quadratic and linear elements, else the -direction of conversion is selected automatically.
        • - + mesh to linear. **Convert to bi-quadratic** option means same as + **Convert to quadratic** except that QUAD9 elements are created + instead of QUAD8, and HEXA27 elements are created instead of + HEXA20. Note that the choice is available only if the selected mesh + (or sub-mesh) contains both quadratic and linear elements, else the + direction of conversion is selected automatically.
      • If it is necessary to place medium nodes of the quadratic mesh on the geometry (meshed object). This option is relevant for conversion to quadratic provided that the mesh is based on a geometry (not imported from file).