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<languages/>
<languages/>
{{TOCright}}

== Create a finite element mesh ==

<div class="mw-translate-fuzzy">
== Создать FEM Mesh ==
== Создать FEM Mesh ==
Анализ методом конечных элементов выполняется на сетке, состоящей из множества треугольных и четырехугольных конечных элементов, которые разделяют исходное тело. Чем точнее будет сетка, тем точнее будут численные результаты, но и время вычисления будет больше. Баланс между размером сетки, временем вычислений и точностью результатов является важной характеристикой четко определенного анализа методом конечных элементов.
Существуют различные возможности для создания FEM Mesh во FreeCAD:
</div>
* Инструмент Netgen для сетки FreeCAD FEM [[FEM_MeshNetgenFromShape | MeshNetgenFromShape]] с использованием графического интерфейса или Python
* Инструмент GMSH для сетки FreeCAD FEM [[FEM_MeshGmshFromShape | MeshGmshFromShape]] с использованием графического интерфейса или Python
* Python напрямую означает создание сетки FEM вручную
* Импорт сетки FEM


<div class="mw-translate-fuzzy">
Objects created in PartDesign and Part are supported, as well as simple copies of those bodies. There are two meshers available to the user: Netgen and GMSH. Netgen is included in FreeCAD. For GMSH an external binary needs to be installed. Refer to [[FEM_Install|FEM Install]]
Существуют различные возможности для создания сетки МКЭ в [[FEM Workbench/ru|верстаке FEM]]:
* [[FEM MeshGmshFromShape/ru|Инструмент GMSH]] с использованием графического интерфейса.
* [[FEM MeshNetgenFromShape/ru|Инструмент Netgen]] с использованием графического интерфейса.
* Импорт сетки из другой программы. В частности, Gmsh и Netgen могут использоваться сами по себе вне FreeCAD с сетками твердых тел вроде файлов Step.
* Создание сетки вручную с помощью скриптов [[Python/ru|Python]].
</div>


<div class="mw-translate-fuzzy">
== FEM Mesh Elements in FreeCAD ==
Инструменты Gmsh и Netgen поддерживают создание сеток из тела, созданных с помощью [[Part Workbench/ru|верстаков Part]] и [[PartDesign Workbench/ru|PartDesign]], а также простые копии этих тел. В общем, любой верстак, который генерирует твердые объекты, например [[Arch Workbench/ru|верстак Arch]], можно использовать для создания сеток. Обратите внимание, что сетка, используемая для FEA, не то же самое что сетка, созданная или импортированная из [[Mesh Workbench/ru|верстака Mesh]].
FreeCAD supports various element types. There is an external blog link which explains about the differences and when to use which element type: https://www.comsol.com/blogs/meshing-your-geometry-various-element-types/
</div>


[[Image:FEM_Workbench_workflow.svg|600px]]
{| class="wikitable" style="color:green; background-color:#ffffcc;" cellpadding="5" cellspacing="0" border="1"
{{Caption|The FEM Workbench calls the external tool Gmsh to obtain a mesh from a solid body created with any workbench in FreeCAD; it can also import a mesh created externally}}
|+ ''' Import and Export of FEM Mesh Elements '''

[[Image:FEM_Mesh.png|600px]]
{{Caption|(1) Solid body created with PartDesign; (2) mesh produced by the Gmsh tool inside the FEM Workbench (all triangles); and (3) mesh produced externally by Gmsh, exported to Abaqus format {{FileName|.inp}}, and then imported into FreeCAD (all quadrangles)}}

The [[FEM_MeshGmshFromShape|Gmsh]] and [[FEM_MeshNetgenFromShape|Netgen tools]] are convenience tools to quickly mesh a body, and thus don't expose the full capabilities of these programs; they normally create triangular meshes, which may not be ideal for some types of analysis. If you'd like to have more control of the created mesh (use only quadrilaterals, precise element number and size, variable resolution of the mesh, etc.), you should use these programs externally, produce a mesh file in a supported format ({{FileName|.inp}}, {{FileName|.unv}}, {{FileName|.vtk}}, {{FileName|.z88}}), and import this file into FreeCAD.

Previously, Netgen was included with FreeCAD and could be used immediately. Now, both Netgen and Gmsh should be installed before they can be used by the [[FEM Workbench]]. Refer to [[FEM_Install|FEM Install]] for instructions.

== Meshing software ==

Meshing software operates on solid bodies that can be in different formats, like Step and Brep. These programs can be used independently of FreeCAD, and typically have many options to control the meshing algorithms, element size, and boundary conditions.

The [[FEM_Workbench|FEM Workbench]] has developed simple communication interfaces to use Gmsh and Netgen directly inside FreeCAD. Other programs don't have an interface, but this could change in the future if there is interest from the community, and if those applications are easy to integrate. The meshing software can be compiled and distributed together with FreeCAD only if its license is compatible with the LGPL2 license; otherwise, the program has to be used as an external binary, like Gmsh (GPL2) is used.

=== Interface implemented in FreeCAD ===

* Gmsh: [http://gmsh.info/ main website], [https://gitlab.onelab.info/gmsh/gmsh code repository]
* Netgen: [https://ngsolve.org/ main website], [https://github.com/NGSolve/netgen code repository]

=== No interface in FreeCAD ===

* ENigMA, [https://forum.freecadweb.org/viewtopic.php?f=18&t=33048 forum thread], [https://github.com/bjaraujo/ENigMA code repository]
* libMesh, [http://libmesh.github.io/ main website], [https://github.com/libMesh/libmesh code repository], [https://forum.freecadweb.org/viewtopic.php?f=18&t=33621 forum thread]; it's a very active project, and it's C++ only
* PythonOCC, [http://www.pythonocc.org/ main website]
* SnappyHexMesh, [https://openfoamwiki.net/index.php/SnappyHexMesh main website]
* Tetgen, [http://wias-berlin.de/software/tetgen/ main website]

== Mesh elements in FreeCAD ==

FreeCAD supports various element types. The following article explains the difference between them, and when should be used: [https://www.comsol.com/blogs/meshing-your-geometry-various-element-types/ Meshing Your Geometry: When to Use the Various Element Types].

{| class="wikitable" style="color:black; background-color:#eeeeef;" cellpadding="5" cellspacing="0" border="1"
|+ Import and export of mesh elements
|-
|-
! Element !! Element !! FreeCAD API !! FreeCAD GUI !! med !! unv !! inp !! frd !! txt !! xml
! Element !! Element !! FreeCAD API !! FreeCAD GUI !! med !! unv !! inp !! frd !! txt !! xml
Line 23: Line 65:
| seg 2 || B31 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]]
| seg 2 || B31 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]]
|-
|-
| seg 3 || B32 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || ni || -
| seg 3 || B32 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || NI || [[File:Edit_Cancel.svg|20px]]
|-
|-
| tria 3 || S3 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || - || [[File:Edit_OK.svg|20px]]
| tria 3 || S3 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_OK.svg|20px]]
|-
|-
| tria 6 || S6 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || -
| tria 6 || S6 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_Cancel.svg|20px]]
|-
|-
| quad 4 || S4 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || - || [[File:Edit_OK.svg|20px]]
| quad 4 || S4 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_OK.svg|20px]]
|-
|-
| quad 8 || S8 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || -
| quad 8 || S8 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_Cancel.svg|20px]]
|-
|-
| tetra 4 || C3D4 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]]
| tetra 4 || C3D4 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]]
|-
|-
| tetra 10 || C3D10 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || -
| tetra 10 || C3D10 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_Cancel.svg|20px]]
|-
|-
| pyra 5 || - || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || - || - || - || - || -
| hexa 8 || C3D8 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || ([[File:Edit_Cancel.svg|20px]]) the format allows it,<br/> but it's not readable or writable by fenics
|-
| pyra 13 || - || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || - || - || - || - || -
|-
| hexa 8 || C3D8 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || (-) [format allows it, but not readable/writable by fenics]
|-
|-
| hexa 20 || C3D20 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || -
| hexa 20 || C3D20 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_Cancel.svg|20px]]
|-
|-
| penta 6 || C3D6 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || ? || -
| penta 6 || C3D6 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || ? || [[File:Edit_Cancel.svg|20px]]
|-
|-
| penta 15 || C3D15 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || ? || -
| penta 15 || C3D15 || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || ? || [[File:Edit_Cancel.svg|20px]]
|-
| pyra 5 || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_Cancel.svg|20px]]
|-
| pyra 13 || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_OK.svg|20px]] || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_Cancel.svg|20px]] || [[File:Edit_Cancel.svg|20px]]
|}
|}
*"ni" means the element type is not implemented in FreeCAD but the format would support it.
*"-" means the format specification does not support this element type, thus FreeCAD can not support it.
*"?" it is not known if the format supports this element type.


* "NI" means the element type is not implemented in FreeCAD but the format would support it.
== FEM Element Types ==
* [[File:Edit_Cancel.svg|20px]] "-" means the format specification does not support this element type, thus FreeCAD cannot support it.
==== General ====
* "?" means it is not known if the format supports this element type.
More informations about the FEM element types and their data structure inside FreeCAD can be find on [[FEM_Element_Types | FEM Element Types]].
==== Segment element ====
[[Image:segments.gif]]
<p> <br /> </p>


==== Triangle element ====
== FEM element types ==
[[Image:triangles.gif]]
<p> <br /> </p>


More information on the elements, and their data structure inside FreeCAD can be found in [[FEM Element Types|FEM Element Types]].
==== Quadratic element ====
[[Image:quadrangles.gif]]
<p> <br /> </p>


==== Tetrahedron element ====
=== Segment element ===
[[Image:tetraedres.gif]]
<p> <br /> </p>


[[Image:FEM_mesh_elements_1_segment.svg|600px]]
==== Pyramid element ====
[[Image:pyramides.gif]]
<p> <br /> </p>


==== Hexahedron element ====
=== Triangle element ===
[[Image:hexaedres.gif]]
<p> <br /> </p>


[[Image:FEM_mesh_elements_2_triangle.svg|600px]]
==== Pentahedron element ====

[[Image:pentaedres.gif]]
=== Quadrangle element ===
<p> <br /> </p>

[[Image:FEM_mesh_elements_3_quadrangle.svg|600px]]

=== Tetrahedron element ===

[[Image:FEM_mesh_elements_4_tetrahedron.svg|600px]]

=== Hexahedron element ===

[[Image:FEM_mesh_elements_5_hexahedron.svg|600px]]

=== Pentahedron element (prism) ===

[[Image:FEM_mesh_elements_6_pentahedron.svg|600px]]

=== Pyramid element ===

[[Image:FEM_mesh_elements_7_pyramid.svg|600px]]


== Scripting ==
== Scripting ==

=== Create a FEM Mesh totally py python ===
====Creating a mesh with one Tet-10 Elements====
=== Create a FEM mesh completely in Python ===

{{Emphasis|See also:}} [[FreeCAD_Scripting_Basics|FreeCAD Scripting Basics]].

The Python API allows the user to define a finite element mesh by directly adding individual nodes, and defining edges, faces, and volumes.

The mesh itself is of type {{incode|Fem::FemMesh}}, which needs to be attached to a proper document object of type {{incode|Fem::FemMeshObject}}.

{{Code|code=
App.ActiveDocument.Mesh_object.TypeId = Fem::FemMeshObject
.
.
.FemMesh.TypeId = Fem::FemMesh
}}

====Creating a mesh with one Tet-10 element====

Create an empty FemMesh, populate it with nodes, create the volume, and finally call {{incode|Fem.show()}} to create the document object with the corresponding mesh.


{{Code|code=
{{Code|code=
import FreeCAD, Fem
import FreeCAD, Fem

# create a empty mesh
m = Fem.FemMesh()
m = Fem.FemMesh()
#create the nodes
m.addNode(0,1,0)
m.addNode(0,0,1)
m.addNode(1,0,0)
m.addNode(0,0,0)
m.addNode(0,0.5,0.5)
m.addNode(0.5,0.03,.5)
m.addNode(0.5,0.5,0.03)
m.addNode(0,0.5,0)
m.addNode(0.03,0,0.5)
m.addNode(0.5,0,0)
# add the volume with the created nodes
m.addVolume([1,2,3,4,5,6,7,8,9,10])


m.addNode(0, 1, 0)
m.addNode(0, 0, 1)
m.addNode(1, 0, 0)
m.addNode(0, 0, 0)
m.addNode(0, 0.5, 0.5)
m.addNode(0.5, 0.03, 0.5)
m.addNode(0.5, 0.5, 0.03)
m.addNode(0, 0.5, 0)
m.addNode(0.03, 0, 0.5)
m.addNode(0.5, 0, 0)

m.addVolume([1,2,3,4,5,6,7,8,9,10])
Fem.show(m)
Fem.show(m)
obj = FreeCAD.ActiveDocument.ActiveObject
}}
}}

If you want to have predefined element and node numbering:
If you want to have predefined node and element numbering, pass the appropriate ID to the node and volume methods.

To create an actual document object, instead of {{incode|Fem.show()}} you can also use the document {{incode|addObject()}} method; then attach the created mesh to this object's {{incode|FemMesh}} attribute.

{{Code|code=
{{Code|code=
a = Fem.FemMesh()
m.addNode(0.0,1.0,0.0,1)

m.addVolume([1,2,3,4,5,6,7,8,9,10],1)
a.addNode(0, 1, 0, 1)
a.addNode(0, 0, 1, 2)
a.addNode(1, 0, 0, 3)
a.addNode(0, 0, 0, 4)
a.addNode(0, 0.5, 0.5, 5)
a.addNode(0.5, 0.03, 0.5, 6)
a.addNode(0.5, 0.5, 0.03, 7)
a.addNode(0, 0.5, 0, 8)
a.addNode(0.03, 0, 0.5, 9)
a.addNode(0.5, 0, 0, 10)


a.addVolume([1,2,3,4,5,6,7,8,9,10], 1)
obj_2 = FreeCAD.ActiveDocument.addObject("Fem::FemMeshObject")
obj_2.Placement.Base = FreeCAD.Vector(2, 0, 0)
obj_2.FemMesh = a
}}
}}


==== Visual properties ====


Once a FemMesh object has been created with {{incode|Fem.show()}}, some of its visual properties can be changed by modifying the different attributes of its {{incode|ViewObject}}. This can be useful to postprocess the mesh after a finite element solution has been obtained.
==== Visual handling ====

Highlight some nodes on the view:
Highlight some nodes in the mesh
{{Code|code=
{{Code|code=
Fem.show(m)
import FreeCAD, Fem
obj = FreeCAD.ActiveDocument.ActiveObject


obj.ViewObject.HighlightedNodes = [1, 2, 3]
m = Fem.FemMesh()
}}


The individual elements of a mesh can be modified by passing a dictionary with the appropriate {{incode|key:value}} pairs.
m.addNode(0,1,0)
m.addNode(0,0,1)
m.addNode(1,0,0)
m.addNode(0,0,0)
m.addNode(0,0.5,0.5)
m.addNode(0.5,0.03,.5)
m.addNode(0.5,0.5,0.03)
m.addNode(0,0.5,0)
m.addNode(0.03,0,0.5)
m.addNode(0.5,0,0)
m.addVolume([1,2,3,4,5,6,7,8,9,10])


Set volume 1 to red
Fem.show(m)

Gui.ActiveDocument.ActiveObject.HighlightedNodes = [1,2,3]
{{Code|code=
obj.ViewObject.ElementColor = {1:(1,0,0)}
}}
}}

Postprocessing colors and displacement:
Set nodes 1, 2 and 3 to a certain color; the faces between the nodes acquire an interpolated color.
Highlight some nodes on the view:

{{Code|code=
{{Code|code=
obj.ViewObject.NodeColor = {1:(1,0,0), 2:(0,1,0), 3:(0,0,1)}
# set the volume 1 to red
Gui.ActiveDocument.ActiveObject.ElementColor= {1:(1,0,0)}
# set the node 1 and 2 to a certain Color and interpolate the survace
Gui.ActiveDocument.ActiveObject.NodeColor= {1:(1,0,0),2:(1,0,0)}
# set the node 1 and 2 to a certain displacement
Gui.ActiveDocument.ActiveObject.NodeDisplacement= {1:FreeCAD.Vector(1,0,0),2:FreeCAD.Vector(1,0,0)}
# double the factor of the displacement shown
Gui.ActiveDocument.ActiveObject.animate(2.0)
}}
}}

=== Script one Element of each supported Element Type ===
Displace the nodes 1 and 2 by the magnitude and direction defined by a vector.

{{Code|code=
obj.ViewObject.NodeDisplacement = {1:FreeCAD.Vector(0,1,0), 2:FreeCAD.Vector(1,0,0)}
}}

Double the factor of the displacement shown. ({{Emphasis|Note to editors: removed in newer versions?}})

{{Code|code=
obj.ViewObject.animate(2.0)
}}

== Scripting examples of each supported element type ==

=== Beam, 2 node line, seg2 (linear) ===

{{Code|code=
{{Code|code=
import Fem
import Fem

#################################################
# Beams
# 2 node line --> seg2 ##########################
seg2 = Fem.FemMesh()
seg2 = Fem.FemMesh()
seg2.addNode( 0, 0, 0, 1)
seg2.addNode( 0, 0, 0, 1)
seg2.addNode(10, 0, 0, 2)
seg2.addNode(10, 0, 0, 2)
seg2.addEdge(1, 2)
seg2.addEdge(1, 2)
seg2
print(seg2)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","seg2")
obj = FreeCAD.ActiveDocument.addObject("Fem::FemMeshObject", "seg2")
obj.FemMesh = seg2
obj.FemMesh = seg2
obj.Placement.Base = (0,110,0)
obj.Placement.Base = FreeCAD.Vector(0, 110, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
}}


=== Beam, 3 node line, seg3 (quadratic) ===


{{Code|code=
# 3 node line --> seg3 ##########################
import Fem


seg3 = Fem.FemMesh()
seg3 = Fem.FemMesh()
seg3.addNode( 0, 0, 0, 1)
seg3.addNode( 0, 0, 0, 1)
seg3.addNode(10, 0, 0, 2)
seg3.addNode(10, 0, 0, 2)
seg3.addNode( 5, 0, 0, 3)
seg3.addNode( 5, 0, 0, 3)
seg3.addEdge([1, 2, 3])
seg3.addEdge([1, 2, 3])
seg3
print(seg3)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","seg3")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "seg3")
obj.FemMesh = seg3
obj.FemMesh = seg3
obj.Placement.Base = (30,110,0)
obj.Placement.Base = FreeCAD.Vector(30, 110, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
}}


=== Shell, 3 node triangle, tria3 (linear) ===

{{Code|code=
import Fem


#################################################
# Shells
# 3 node triangle --> tria3 #####################
tria3 = Fem.FemMesh()
tria3 = Fem.FemMesh()
tria3.addNode( 0, 0, 0, 1)
tria3.addNode( 0, 0, 0, 1)
tria3.addNode( 6, 12, 0, 2)
tria3.addNode( 6, 12, 0, 2)
tria3.addNode(12, 0, 0, 3)
tria3.addNode(12, 0, 0, 3)
tria3.addFace([1, 2, 3])
tria3.addFace([1, 2, 3])
tria3
print(tria3)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","tria3")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "tria3")
obj.FemMesh = tria3
obj.FemMesh = tria3
obj.Placement.Base = (0,80,0)
obj.Placement.Base = FreeCAD.Vector(0, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
obj.ViewObject.BackfaceCulling = False
}}
# add Face with element number

Add a face with the element number.

{{Code|code=
elemtria3 = Fem.FemMesh()
elemtria3 = Fem.FemMesh()
nds = tria3.Nodes
nodes = tria3.Nodes
for n in nds:
for n in nodes:
elemtria3.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elemtria3.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elemtria3.addFace([1, 2, 3], 88)


obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemtria3")
elemtria3.addFace([1, 2, 3], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elemtria3")
obj.FemMesh = elemtria3
obj.FemMesh = elemtria3
obj.Placement.Base = (200,80,0)
obj.Placement.Base = FreeCAD.Vector(200, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
obj.ViewObject.BackfaceCulling = False
elemtria3.Faces
print(elemtria3.Faces)
}}


=== Shell, 6 node triangle, tria6 (quadratic) ===

{{Code|code=
import Fem


# 6 node triangle --> tria 6 ####################
tria6 = Fem.FemMesh()
tria6 = Fem.FemMesh()
tria6.addNode( 0, 0, 0, 1)
tria6.addNode( 0, 0, 0, 1)
Line 218: Line 318:
tria6.addNode( 9, 6, 0, 5)
tria6.addNode( 9, 6, 0, 5)
tria6.addNode( 6, 0, 0, 6)
tria6.addNode( 6, 0, 0, 6)
tria6.addFace([1, 2, 3, 4, 5, 6])
tria6.addFace([1, 2, 3, 4, 5, 6])
tria6
print(tria6)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","tria6")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "tria6")
obj.FemMesh = tria6
obj.FemMesh = tria6
obj.Placement.Base = (30,80,0)
obj.Placement.Base = FreeCAD.Vector(30, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
obj.ViewObject.BackfaceCulling = False
}}
# add Face with element number

Add a face with the element number.

{{Code|code=
elemtria6 = Fem.FemMesh()
elemtria6 = Fem.FemMesh()
nds = tria6.Nodes
nodes = tria6.Nodes
for n in nds:
for n in nodes:
elemtria6.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elemtria6.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elemtria6.addFace([1, 2, 3, 4, 5, 6], 88)
elemtria6.addFace([1, 2, 3, 4, 5, 6], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elemtria6")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemtria6")
obj.FemMesh = elemtria6
obj.FemMesh = elemtria6
obj.Placement.Base = (230,80,0)
obj.Placement.Base = FreeCAD.Vector(230, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
obj.ViewObject.BackfaceCulling = False
elemtria6.Faces
print(elemtria6.Faces)
}}


=== Shell, 4 node quadrangle, quad4 (linear) ===

{{Code|code=
import Fem


# 4 node quad --> quad4 #########################
quad4 = Fem.FemMesh()
quad4 = Fem.FemMesh()
quad4.addNode( 0, 10, 0, 1)
quad4.addNode( 0, 10, 0, 1)
Line 246: Line 355:
quad4.addNode(10, 0, 0, 3)
quad4.addNode(10, 0, 0, 3)
quad4.addNode( 0, 0, 0, 4)
quad4.addNode( 0, 0, 0, 4)
quad4.addFace([1, 2, 3, 4])
quad4.addFace([1, 2, 3, 4])
quad4
print(quad4)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","quad4")
obj = FreeCAD.ActiveDocument.addObject("Fem::FemMeshObject", "quad4")
obj.FemMesh = quad4
obj.FemMesh = quad4
obj.Placement.Base = (60,80,0)
obj.Placement.Base = FreeCAD.Vector(60, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
obj.ViewObject.BackfaceCulling = False
}}
# add Face with element number

Add a face with the element number.

{{Code|code=
elemquad4 = Fem.FemMesh()
elemquad4 = Fem.FemMesh()
nds = quad4.Nodes
nodes = quad4.Nodes
for n in nds:
for n in nodes:
elemquad4.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elemquad4.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elemquad4.addFace([1, 2, 3, 4], 88)
elemquad4.addFace([1, 2, 3, 4], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elemquad4")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemquad4")
obj.FemMesh = elemquad4
obj.FemMesh = elemquad4
obj.Placement.Base = (260,80,0)
obj.Placement.Base = FreeCAD.Vector(260, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
obj.ViewObject.BackfaceCulling = False
elemquad4.Faces
print(elemquad4.Faces)
}}


=== Shell, 8 node quadrangle, quad8 (quadratic) ===

{{Code|code=
import Fem


# 8 node quad --> quad8 #########################
quad8 = Fem.FemMesh()
quad8 = Fem.FemMesh()
quad8.addNode( 0, 10, 0, 1)
quad8.addNode( 0, 10, 0, 1)
Line 278: Line 396:
quad8.addNode( 5, 0, 0, 7)
quad8.addNode( 5, 0, 0, 7)
quad8.addNode( 0, 5, 0, 8)
quad8.addNode( 0, 5, 0, 8)
quad8.addFace([1, 2, 3, 4, 5, 6, 7, 8])
quad8.addFace([1, 2, 3, 4, 5, 6, 7, 8])
quad8
print(quad8)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","quad8")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "quad8")
obj.FemMesh = quad8
obj.FemMesh = quad8
obj.Placement.Base = FreeCAD.Vector(90, 80, 0)
obj.ViewObject.BackfaceCulling = False
obj.Placement.Base = (90,80,0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
# add Face with element number
}}

Add a face with the element number.

{{Code|code=
elemquad8 = Fem.FemMesh()
elemquad8 = Fem.FemMesh()
nds = quad8.Nodes
nodes = quad8.Nodes
for n in nds:
for n in nodes:
elemquad8.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elemquad8.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elemquad8.addFace([1, 2, 3, 4, 5, 6, 7, 8], 88)
elemquad8.addFace([1, 2, 3, 4, 5, 6, 7, 8], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elemquad8")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemquad8")
obj.FemMesh = elemquad8
obj.FemMesh = elemquad8
obj.Placement.Base = (290,80,0)
obj.Placement.Base = FreeCAD.Vector(290, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
obj.ViewObject.BackfaceCulling = False
elemquad8.Faces
print(elemquad8.Faces)
}}


=== Volume, 4 node tetrahedron, tetra4 (linear) ===

{{Code|code=
import Fem


#################################################
# Volumes
# 4 node tetrahedron --> tetra4 #################
tetra4 = Fem.FemMesh()
tetra4 = Fem.FemMesh()
tetra4.addNode( 6, 12, 18, 1)
tetra4.addNode( 6, 12, 18, 1)
Line 308: Line 433:
tetra4.addNode(12, 0, 18, 3)
tetra4.addNode(12, 0, 18, 3)
tetra4.addNode( 6, 6, 0, 4)
tetra4.addNode( 6, 6, 0, 4)
tetra4.addVolume([1, 2, 3, 4])
tetra4.addVolume([1, 2, 3, 4])
tetra4
print(tetra4)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","tetra4")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "tetra4")
obj.FemMesh = tetra4
obj.FemMesh = tetra4
obj.Placement.Base = (0,50,0)
obj.Placement.Base = FreeCAD.Vector(0, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
}}
# add Volume with element number

Add a volume with the element number.

{{Code|code=
elemtetra4 = Fem.FemMesh()
elemtetra4 = Fem.FemMesh()
nds = tetra4.Nodes
nodes = tetra4.Nodes
for n in nds:
for n in nodes:
elemtetra4.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elemtetra4.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elemtetra4.addVolume([1, 2, 3, 4], 88)
elemtetra4.addVolume([1, 2, 3, 4], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elemtetra4")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemtetra4")
obj.FemMesh = elemtetra4
obj.FemMesh = elemtetra4
obj.Placement.Base = (200,50,0)
obj.Placement.Base = FreeCAD.Vector(200, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
elemtetra4.Volumes
print(elemtetra4.Volumes)
}}


=== Volume, 10 node tetrahedron, tetra10 (quadratic) ===

{{Code|code=
import Fem


# 10 node tetrahedron --> tetra10 ###############
tetra10 = Fem.FemMesh()
tetra10 = Fem.FemMesh()
tetra10.addNode( 6, 12, 18, 1)
tetra10.addNode( 6, 12, 18, 1)
Line 343: Line 477:
tetra10.addNode( 9, 3, 9,10)
tetra10.addNode( 9, 3, 9,10)
tetra10.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
tetra10.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
tetra10
print(tetra10)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","tetra10")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "tetra10")
obj.FemMesh = tetra10
obj.FemMesh = tetra10
obj.Placement.Base = (30,50,0)
obj.Placement.Base = FreeCAD.Vector(30, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
}}
# add Volume with element number

Add a volume with the element number.

{{Code|code=
elemtetra10 = Fem.FemMesh()
elemtetra10 = Fem.FemMesh()
nds = tetra10.Nodes
nodes = tetra10.Nodes
for n in nds:
for n in nodes:
elemtetra10.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elemtetra10.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elemtetra10.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 88)
elemtetra10.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elemtetra10")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemtetra10")
obj.FemMesh = elemtetra10
obj.FemMesh = elemtetra10
obj.Placement.Base = (230,50,0)
obj.Placement.Base = FreeCAD.Vector(230, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
elemtetra10.Volumes
print(elemtetra10.Volumes)
}}


=== Volume, 8 node hexahedron, hexa8 (linear) ===

{{Code|code=
import Fem


# 8 node Hexahedron --> hexa8 ###################
hexa8 = Fem.FemMesh()
hexa8 = Fem.FemMesh()
hexa8.addNode( 0, 10, 10, 1)
hexa8.addNode( 0, 10, 10, 1)
Line 373: Line 516:
hexa8.addNode(10, 10, 0, 8)
hexa8.addNode(10, 10, 0, 8)
hexa8.addVolume([1, 2, 3, 4, 5, 6, 7, 8])
hexa8.addVolume([1, 2, 3, 4, 5, 6, 7, 8])
hexa8
print(hexa8)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","hexa8")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "hexa8")
obj.FemMesh = hexa8
obj.FemMesh = hexa8
obj.Placement.Base = (60,50,0)
obj.Placement.Base = FreeCAD.Vector(60, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
}}
# add Volume with element number

Add a volume with the element number.

{{Code|code=
elemhexa8 = Fem.FemMesh()
elemhexa8 = Fem.FemMesh()
nds = hexa8.Nodes
nodes = hexa8.Nodes
for n in nds:
for n in nodes:
elemhexa8.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elemhexa8.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elemhexa8.addVolume([1, 2, 3, 4, 5, 6, 7, 8], 88)
elemhexa8.addVolume([1, 2, 3, 4, 5, 6, 7, 8], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elemhexa8")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemhexa8")
obj.FemMesh = elemhexa8
obj.FemMesh = elemhexa8
obj.Placement.Base = (260,50,0)
obj.Placement.Base = FreeCAD.Vector(260, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
elemhexa8.Volumes
print(elemhexa8.Volumes)
}}


=== Volume, 20 node hexahedron, hexa20 (quadratic) ===

{{Code|code=
import Fem


# 20 node Hexahedron --> hexa20 #################
hexa20 = Fem.FemMesh()
hexa20 = Fem.FemMesh()
hexa20.addNode( 0, 10, 10, 1)
hexa20.addNode( 0, 10, 10, 1)
Line 418: Line 570:
hexa20.addNode(10, 10, 5, 20)
hexa20.addNode(10, 10, 5, 20)
hexa20.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20])
hexa20.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20])
hexa20
print(hexa20)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","hexa20")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "hexa20")
obj.FemMesh = hexa20
obj.FemMesh = hexa20
obj.Placement.Base = (90,50,0)
obj.Placement.Base = FreeCAD.Vector(90, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
}}
# add Volume with element number

Add a volume with the element number.

{{Code|code=
elemhexa20 = Fem.FemMesh()
elemhexa20 = Fem.FemMesh()
nds = hexa20.Nodes
nodes = hexa20.Nodes
for n in nds:
for n in nodes:
elemhexa20.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elemhexa20.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elemhexa20.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20], 88)
elemhexa20.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elemhexa20")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemhexa20")
obj.FemMesh = elemhexa20
obj.FemMesh = elemhexa20
obj.Placement.Base = (290,50,0)
obj.Placement.Base = FreeCAD.Vector(290, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
elemhexa20.Volumes
print(elemhexa20.Volumes)
}}


=== Volume, 6 node pentahedron, penta6 (linear) ===

{{Code|code=
import Fem


# 6 node pentahedron --> penta6 #################
penta6 = Fem.FemMesh()
penta6 = Fem.FemMesh()
penta6.addNode(10,10,10, 1)
penta6.addNode(10, 10, 10, 1)
penta6.addNode( 0, 0,10, 2)
penta6.addNode( 0, 0, 10, 2)
penta6.addNode(20, 0,10, 3)
penta6.addNode(20, 0, 10, 3)
penta6.addNode(10,10, 0, 4)
penta6.addNode(10, 10, 0, 4)
penta6.addNode( 0, 0, 0, 5)
penta6.addNode( 0, 0, 0, 5)
penta6.addNode(20, 0, 0, 6)
penta6.addNode(20, 0, 0, 6)
penta6.addVolume([1, 2, 3, 4, 5, 6])
penta6.addVolume([1, 2, 3, 4, 5, 6])
penta6
print(penta6)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","penta6")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "penta6")
obj.FemMesh = penta6
obj.FemMesh = penta6
obj.Placement.Base = (0,0,0)
obj.Placement.Base = FreeCAD.Vector(0, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
}}
# add Volume with element number

Add a volume with the element number.

{{Code|code=
elempenta6 = Fem.FemMesh()
elempenta6 = Fem.FemMesh()
nds = penta6.Nodes
nodes = penta6.Nodes
for n in nds:
for n in nodes:
elempenta6.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elempenta6.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elempenta6.addVolume([ 1, 2, 3, 4, 5, 6], 88)
elempenta6.addVolume([ 1, 2, 3, 4, 5, 6], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elempenta6")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elempenta6")
obj.FemMesh = elempenta6
obj.FemMesh = elempenta6
obj.Placement.Base = (200,0,0)
obj.Placement.Base = FreeCAD.Vector(200, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
elempenta6.Volumes
print(elempenta6.Volumes)
}}


=== Volume, 15 node pentahedron, penta15 (quadratic) ===

{{Code|code=
import Fem


# 15 node pentahedron --> penta15 ###############
penta15 = Fem.FemMesh()
penta15 = Fem.FemMesh()
penta15.addNode(10,10,10, 1)
penta15.addNode(10, 10, 10, 1)
penta15.addNode( 0, 0,10, 2)
penta15.addNode( 0, 0, 10, 2)
penta15.addNode(20, 0,10, 3)
penta15.addNode(20, 0, 10, 3)
penta15.addNode(10,10, 0, 4)
penta15.addNode(10, 10, 0, 4)
penta15.addNode( 0, 0, 0, 5)
penta15.addNode( 0, 0, 0, 5)
penta15.addNode(20, 0, 0, 6)
penta15.addNode(20, 0, 0, 6)


penta15.addNode( 5, 5,10, 7)
penta15.addNode( 5, 5, 10, 7)
penta15.addNode(10, 0,10, 8)
penta15.addNode(10, 0, 10, 8)
penta15.addNode(15, 5,10, 9)
penta15.addNode(15, 5, 10, 9)


penta15.addNode( 5, 5, 0,10)
penta15.addNode( 5, 5, 0, 10)
penta15.addNode(10, 0, 0,11)
penta15.addNode(10, 0, 0, 11)
penta15.addNode(15, 5, 0,12)
penta15.addNode(15, 5, 0, 12)


penta15.addNode(10,10, 5,13)
penta15.addNode(10, 10, 5, 13)
penta15.addNode( 0, 0, 5,14)
penta15.addNode( 0, 0, 5, 14)
penta15.addNode(20, 0, 5,15)
penta15.addNode(20, 0, 5, 15)
penta15.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15])
penta15.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15])
penta15
print(penta15)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","penta15")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "penta15")
obj.FemMesh = penta15
obj.FemMesh = penta15
obj.Placement.Base = (40,0,0)
obj.Placement.Base = FreeCAD.Vector(40, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
}}
# add Volume with element number

Add a volume with the element number.

{{Code|code=
elempenta15 = Fem.FemMesh()
elempenta15 = Fem.FemMesh()
nds = penta15.Nodes
nodes = penta15.Nodes
for n in nds:
for n in nodes:
elempenta15.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elempenta15.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elempenta15.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15], 88)
elempenta15.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elempenta15")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elempenta15")
obj.FemMesh = elempenta15
obj.FemMesh = elempenta15
obj.Placement.Base = (240,0,0)
obj.Placement.Base = FreeCAD.Vector(240, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
elempenta15.Volumes
print(elempenta15.Volumes)
}}


=== Volume, 5 node pyramid, pyra5 (linear) ===

{{Code|code=
import Fem


# 5 node pyramid --> pyra5 ######################
pyra5 = Fem.FemMesh()
pyra5 = Fem.FemMesh()
pyra5.addNode( 0,20, 0, 1)
pyra5.addNode( 0, 20, 0, 1)
pyra5.addNode(20,20, 0, 2)
pyra5.addNode(20, 20, 0, 2)
pyra5.addNode(20, 0, 0, 3)
pyra5.addNode(20, 0, 0, 3)
pyra5.addNode( 0, 0, 0, 4)
pyra5.addNode( 0, 0, 0, 4)
pyra5.addNode(10,10,10, 5)
pyra5.addNode(10, 10, 10, 5)
pyra5.addVolume([1, 2, 3, 4, 5])
pyra5.addVolume([1, 2, 3, 4, 5])
pyra5
print(pyra5)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","pyra5")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "pyra5")
obj.FemMesh = pyra5
obj.FemMesh = pyra5
obj.Placement.Base = (80,0,0)
obj.Placement.Base = FreeCAD.Vector(80, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
}}
# add Volume with element number

Add a volume with the element number.

{{Code|code=
elempyra5 = Fem.FemMesh()
elempyra5 = Fem.FemMesh()
nds = pyra5.Nodes
nodes = pyra5.Nodes
for n in nds:
for n in nodes:
elempyra5.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elempyra5.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elempyra5.addVolume([1, 2, 3, 4, 5], 88)
elempyra5.addVolume([1, 2, 3, 4, 5], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elempyra5")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elempyra5")
obj.FemMesh = elempyra5
obj.FemMesh = elempyra5
obj.Placement.Base = (280,0,0)
obj.Placement.Base = FreeCAD.Vector(280, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
elempyra5.Volumes
print(elempyra5.Volumes)
}}


=== Volume, 13 node pyramid, pyra13 (quadratic) ===

{{Code|code=
import Fem


# 13 node pyramid --> pyra13 ####################
pyra13 = Fem.FemMesh()
pyra13 = Fem.FemMesh()
pyra13.addNode( 0,20, 0, 1)
pyra13.addNode( 0, 20, 0, 1)
pyra13.addNode(20,20, 0, 2)
pyra13.addNode(20, 20, 0, 2)
pyra13.addNode(20, 0, 0, 3)
pyra13.addNode(20, 0, 0, 3)
pyra13.addNode( 0, 0, 0, 4)
pyra13.addNode( 0, 0, 0, 4)
pyra13.addNode(10,10,10, 5)
pyra13.addNode(10, 10, 10, 5)


pyra13.addNode(10,20, 0, 6)
pyra13.addNode(10, 20, 0, 6)
pyra13.addNode(20,10, 0, 7)
pyra13.addNode(20, 10, 0, 7)
pyra13.addNode(10, 0, 0, 8)
pyra13.addNode(10, 0, 0, 8)
pyra13.addNode( 0,10, 0, 9)
pyra13.addNode( 0, 10, 0, 9)


pyra13.addNode( 5,15, 5,10)
pyra13.addNode( 5, 15, 5, 10)
pyra13.addNode(15,15, 5,11)
pyra13.addNode(15, 15, 5, 11)
pyra13.addNode(15, 5, 5,12)
pyra13.addNode(15, 5, 5, 12)
pyra13.addNode( 5, 5, 5, 13)
pyra5 = Fem.FemMesh()
pyra13.addNode( 5, 5, 5,13)
pyra13.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13])
pyra13.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13])
pyra13
print(pyra13)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject","pyra13")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "pyra13")
obj.FemMesh = pyra13
obj.FemMesh = pyra13
obj.Placement.Base = (120,0,0)
obj.Placement.Base = FreeCAD.Vector(120, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
}}
# add Volume with element number

Add a volume with the element number.

{{Code|code=
elempyra13 = Fem.FemMesh()
elempyra13 = Fem.FemMesh()
nds = pyra13.Nodes
nodes = pyra13.Nodes
for n in nds:
for n in nodes:
elempyra13.addNode(nds[n].x, nds[n].y, nds[n].z, n)
elempyra13.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)


elempyra13.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13], 88)
elempyra13.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject","elempyra13")
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elempyra13")
obj.FemMesh = elempyra13
obj.FemMesh = elempyra13
obj.Placement.Base = (320,0,0)
obj.Placement.Base = FreeCAD.Vector(320, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
elempyra13.Volumes
print(elempyra13.Volumes)

}}
}}
[[Fem Workbench/ru|FEM Workbench]]


== Scripting examples for groups ==
[[Category:User Documentation/ru]]

See for example https://forum.freecadweb.org/viewtopic.php?f=18&t=37304&start=20#p318823


{{FEM Tools navi{{#translation:}}}}
{{Userdocnavi{{#translation:}}}}
{{clear}}
{{clear}}

Revision as of 10:06, 31 December 2021

Other languages:

Create a finite element mesh

Создать FEM Mesh

Анализ методом конечных элементов выполняется на сетке, состоящей из множества треугольных и четырехугольных конечных элементов, которые разделяют исходное тело. Чем точнее будет сетка, тем точнее будут численные результаты, но и время вычисления будет больше. Баланс между размером сетки, временем вычислений и точностью результатов является важной характеристикой четко определенного анализа методом конечных элементов.

Существуют различные возможности для создания сетки МКЭ в верстаке FEM:

  • Инструмент GMSH с использованием графического интерфейса.
  • Инструмент Netgen с использованием графического интерфейса.
  • Импорт сетки из другой программы. В частности, Gmsh и Netgen могут использоваться сами по себе вне FreeCAD с сетками твердых тел вроде файлов Step.
  • Создание сетки вручную с помощью скриптов Python.

Инструменты Gmsh и Netgen поддерживают создание сеток из тела, созданных с помощью верстаков Part и PartDesign, а также простые копии этих тел. В общем, любой верстак, который генерирует твердые объекты, например верстак Arch, можно использовать для создания сеток. Обратите внимание, что сетка, используемая для FEA, не то же самое что сетка, созданная или импортированная из верстака Mesh.

The FEM Workbench calls the external tool Gmsh to obtain a mesh from a solid body created with any workbench in FreeCAD; it can also import a mesh created externally

(1) Solid body created with PartDesign; (2) mesh produced by the Gmsh tool inside the FEM Workbench (all triangles); and (3) mesh produced externally by Gmsh, exported to Abaqus format .inp, and then imported into FreeCAD (all quadrangles)

The Gmsh and Netgen tools are convenience tools to quickly mesh a body, and thus don't expose the full capabilities of these programs; they normally create triangular meshes, which may not be ideal for some types of analysis. If you'd like to have more control of the created mesh (use only quadrilaterals, precise element number and size, variable resolution of the mesh, etc.), you should use these programs externally, produce a mesh file in a supported format (.inp, .unv, .vtk, .z88), and import this file into FreeCAD.

Previously, Netgen was included with FreeCAD and could be used immediately. Now, both Netgen and Gmsh should be installed before they can be used by the FEM Workbench. Refer to FEM Install for instructions.

Meshing software

Meshing software operates on solid bodies that can be in different formats, like Step and Brep. These programs can be used independently of FreeCAD, and typically have many options to control the meshing algorithms, element size, and boundary conditions.

The FEM Workbench has developed simple communication interfaces to use Gmsh and Netgen directly inside FreeCAD. Other programs don't have an interface, but this could change in the future if there is interest from the community, and if those applications are easy to integrate. The meshing software can be compiled and distributed together with FreeCAD only if its license is compatible with the LGPL2 license; otherwise, the program has to be used as an external binary, like Gmsh (GPL2) is used.

Interface implemented in FreeCAD

No interface in FreeCAD

Mesh elements in FreeCAD

FreeCAD supports various element types. The following article explains the difference between them, and when should be used: Meshing Your Geometry: When to Use the Various Element Types.

Import and export of mesh elements
Element Element FreeCAD API FreeCAD GUI med unv inp frd txt xml
Med CalculiX Python FEM Mesh SMESH IDEAS/FreeCAD Abaqus/CalculiX Result Mesh Z88 Fenics
Name Name create elements view elements import/export import/export import/export import import/export import/export
seg 2 B31
seg 3 B32 NI
tria 3 S3
tria 6 S6
quad 4 S4
quad 8 S8
tetra 4 C3D4
tetra 10 C3D10
hexa 8 C3D8 () the format allows it,
but it's not readable or writable by fenics
hexa 20 C3D20
penta 6 C3D6 ?
penta 15 C3D15 ?
pyra 5
pyra 13
  • "NI" means the element type is not implemented in FreeCAD but the format would support it.
  • "-" means the format specification does not support this element type, thus FreeCAD cannot support it.
  • "?" means it is not known if the format supports this element type.

FEM element types

More information on the elements, and their data structure inside FreeCAD can be found in FEM Element Types.

Segment element

Triangle element

Quadrangle element

Tetrahedron element

Hexahedron element

Pentahedron element (prism)

Pyramid element

Scripting

Create a FEM mesh completely in Python

See also: FreeCAD Scripting Basics.

The Python API allows the user to define a finite element mesh by directly adding individual nodes, and defining edges, faces, and volumes.

The mesh itself is of type Fem::FemMesh, which needs to be attached to a proper document object of type Fem::FemMeshObject.

App.ActiveDocument.Mesh_object.TypeId = Fem::FemMeshObject
                              .
                              .
                              .FemMesh.TypeId = Fem::FemMesh

Creating a mesh with one Tet-10 element

Create an empty FemMesh, populate it with nodes, create the volume, and finally call Fem.show() to create the document object with the corresponding mesh.

import FreeCAD, Fem

m = Fem.FemMesh()

m.addNode(0,    1,    0)
m.addNode(0,    0,    1)
m.addNode(1,    0,    0)
m.addNode(0,    0,    0)
m.addNode(0,    0.5,  0.5)
m.addNode(0.5,  0.03, 0.5)
m.addNode(0.5,  0.5,  0.03)
m.addNode(0,    0.5,  0)
m.addNode(0.03, 0,    0.5)
m.addNode(0.5,  0,    0)

m.addVolume([1,2,3,4,5,6,7,8,9,10])
Fem.show(m)
obj = FreeCAD.ActiveDocument.ActiveObject

If you want to have predefined node and element numbering, pass the appropriate ID to the node and volume methods.

To create an actual document object, instead of Fem.show() you can also use the document addObject() method; then attach the created mesh to this object's FemMesh attribute.

a = Fem.FemMesh()

a.addNode(0,    1,    0,    1)
a.addNode(0,    0,    1,    2)
a.addNode(1,    0,    0,    3)
a.addNode(0,    0,    0,    4)
a.addNode(0,    0.5,  0.5,  5)
a.addNode(0.5,  0.03, 0.5,  6)
a.addNode(0.5,  0.5,  0.03, 7)
a.addNode(0,    0.5,  0,    8)
a.addNode(0.03, 0,    0.5,  9)
a.addNode(0.5,  0,    0,   10)

a.addVolume([1,2,3,4,5,6,7,8,9,10], 1)
obj_2 = FreeCAD.ActiveDocument.addObject("Fem::FemMeshObject")
obj_2.Placement.Base = FreeCAD.Vector(2, 0, 0)
obj_2.FemMesh = a

Visual properties

Once a FemMesh object has been created with Fem.show(), some of its visual properties can be changed by modifying the different attributes of its ViewObject. This can be useful to postprocess the mesh after a finite element solution has been obtained.

Highlight some nodes in the mesh

Fem.show(m)
obj = FreeCAD.ActiveDocument.ActiveObject

obj.ViewObject.HighlightedNodes = [1, 2, 3]

The individual elements of a mesh can be modified by passing a dictionary with the appropriate key:value pairs.

Set volume 1 to red

obj.ViewObject.ElementColor = {1:(1,0,0)}

Set nodes 1, 2 and 3 to a certain color; the faces between the nodes acquire an interpolated color.

obj.ViewObject.NodeColor = {1:(1,0,0), 2:(0,1,0), 3:(0,0,1)}

Displace the nodes 1 and 2 by the magnitude and direction defined by a vector.

obj.ViewObject.NodeDisplacement = {1:FreeCAD.Vector(0,1,0), 2:FreeCAD.Vector(1,0,0)}

Double the factor of the displacement shown. (Note to editors: removed in newer versions?)

obj.ViewObject.animate(2.0)

Scripting examples of each supported element type

Beam, 2 node line, seg2 (linear)

import Fem

seg2 = Fem.FemMesh()
seg2.addNode( 0, 0, 0, 1)
seg2.addNode(10, 0, 0, 2)
seg2.addEdge(1, 2)
print(seg2)

obj = FreeCAD.ActiveDocument.addObject("Fem::FemMeshObject", "seg2")
obj.FemMesh = seg2
obj.Placement.Base = FreeCAD.Vector(0, 110, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"

Beam, 3 node line, seg3 (quadratic)

import Fem

seg3 = Fem.FemMesh()
seg3.addNode( 0, 0, 0, 1)
seg3.addNode(10, 0, 0, 2)
seg3.addNode( 5, 0, 0, 3)
seg3.addEdge([1, 2, 3])
print(seg3)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "seg3")
obj.FemMesh = seg3
obj.Placement.Base = FreeCAD.Vector(30, 110, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"

Shell, 3 node triangle, tria3 (linear)

import Fem

tria3 = Fem.FemMesh()
tria3.addNode( 0,  0, 0, 1)
tria3.addNode( 6, 12, 0, 2)
tria3.addNode(12,  0, 0, 3)
tria3.addFace([1, 2, 3])
print(tria3)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "tria3")
obj.FemMesh = tria3
obj.Placement.Base = FreeCAD.Vector(0, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False

Add a face with the element number.

elemtria3 = Fem.FemMesh()
nodes = tria3.Nodes
for n in nodes:
    elemtria3.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elemtria3.addFace([1, 2, 3], 88)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemtria3")
obj.FemMesh = elemtria3
obj.Placement.Base = FreeCAD.Vector(200, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
print(elemtria3.Faces)

Shell, 6 node triangle, tria6 (quadratic)

import Fem

tria6 = Fem.FemMesh()
tria6.addNode( 0,  0, 0, 1)
tria6.addNode( 6, 12, 0, 2)
tria6.addNode(12,  0, 0, 3)
tria6.addNode( 3,  6, 0, 4)
tria6.addNode( 9,  6, 0, 5)
tria6.addNode( 6,  0, 0, 6)
tria6.addFace([1, 2, 3, 4, 5, 6])
print(tria6)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "tria6")
obj.FemMesh = tria6
obj.Placement.Base = FreeCAD.Vector(30, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False

Add a face with the element number.

elemtria6 = Fem.FemMesh()
nodes = tria6.Nodes
for n in nodes:
    elemtria6.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elemtria6.addFace([1, 2, 3, 4, 5, 6], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemtria6")
obj.FemMesh = elemtria6
obj.Placement.Base = FreeCAD.Vector(230, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
print(elemtria6.Faces)

Shell, 4 node quadrangle, quad4 (linear)

import Fem

quad4 = Fem.FemMesh()
quad4.addNode( 0, 10, 0, 1)
quad4.addNode(10, 10, 0, 2)
quad4.addNode(10,  0, 0, 3)
quad4.addNode( 0,  0, 0, 4)
quad4.addFace([1, 2, 3, 4])
print(quad4)

obj = FreeCAD.ActiveDocument.addObject("Fem::FemMeshObject", "quad4")
obj.FemMesh = quad4
obj.Placement.Base = FreeCAD.Vector(60, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False

Add a face with the element number.

elemquad4 = Fem.FemMesh()
nodes = quad4.Nodes
for n in nodes:
    elemquad4.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elemquad4.addFace([1, 2, 3, 4], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemquad4")
obj.FemMesh = elemquad4
obj.Placement.Base = FreeCAD.Vector(260, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
print(elemquad4.Faces)

Shell, 8 node quadrangle, quad8 (quadratic)

import Fem

quad8 = Fem.FemMesh()
quad8.addNode( 0, 10, 0, 1)
quad8.addNode(10, 10, 0, 2)
quad8.addNode(10,  0, 0, 3)
quad8.addNode( 0,  0, 0, 4)
quad8.addNode( 5, 10, 0, 5)
quad8.addNode(10,  5, 0, 6)
quad8.addNode( 5,  0, 0, 7)
quad8.addNode( 0,  5, 0, 8)
quad8.addFace([1, 2, 3, 4, 5, 6, 7, 8])
print(quad8)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "quad8")
obj.FemMesh = quad8
obj.Placement.Base = FreeCAD.Vector(90, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False

Add a face with the element number.

elemquad8 = Fem.FemMesh()
nodes = quad8.Nodes
for n in nodes:
    elemquad8.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elemquad8.addFace([1, 2, 3, 4, 5, 6, 7, 8], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemquad8")
obj.FemMesh = elemquad8
obj.Placement.Base = FreeCAD.Vector(290, 80, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
obj.ViewObject.BackfaceCulling = False
print(elemquad8.Faces)

Volume, 4 node tetrahedron, tetra4 (linear)

import Fem

tetra4 = Fem.FemMesh()
tetra4.addNode( 6, 12, 18, 1)
tetra4.addNode( 0,  0, 18, 2)
tetra4.addNode(12,  0, 18, 3)
tetra4.addNode( 6,  6,  0, 4)
tetra4.addVolume([1, 2, 3, 4])
print(tetra4)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "tetra4")
obj.FemMesh = tetra4
obj.Placement.Base = FreeCAD.Vector(0, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"

Add a volume with the element number.

elemtetra4 = Fem.FemMesh()
nodes = tetra4.Nodes
for n in nodes:
    elemtetra4.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elemtetra4.addVolume([1, 2, 3, 4], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemtetra4")
obj.FemMesh = elemtetra4
obj.Placement.Base = FreeCAD.Vector(200, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
print(elemtetra4.Volumes)

Volume, 10 node tetrahedron, tetra10 (quadratic)

import Fem

tetra10 = Fem.FemMesh()
tetra10.addNode( 6, 12, 18, 1)
tetra10.addNode( 0,  0, 18, 2)
tetra10.addNode(12,  0, 18, 3)
tetra10.addNode( 6,  6,  0, 4)

tetra10.addNode( 3,  6, 18, 5)
tetra10.addNode( 6,  0, 18, 6)
tetra10.addNode( 9,  6, 18, 7)

tetra10.addNode( 6,  9,  9, 8)
tetra10.addNode( 3,  3,  9, 9)
tetra10.addNode( 9,  3,  9,10)
tetra10.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
print(tetra10)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "tetra10")
obj.FemMesh = tetra10
obj.Placement.Base = FreeCAD.Vector(30, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"

Add a volume with the element number.

elemtetra10 = Fem.FemMesh()
nodes = tetra10.Nodes
for n in nodes:
    elemtetra10.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elemtetra10.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemtetra10")
obj.FemMesh = elemtetra10
obj.Placement.Base = FreeCAD.Vector(230, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
print(elemtetra10.Volumes)

Volume, 8 node hexahedron, hexa8 (linear)

import Fem

hexa8 = Fem.FemMesh()
hexa8.addNode( 0, 10, 10, 1)
hexa8.addNode( 0,  0, 10, 2)
hexa8.addNode(10,  0, 10, 3)
hexa8.addNode(10, 10, 10, 4)
hexa8.addNode( 0, 10,  0, 5)
hexa8.addNode( 0,  0,  0, 6)
hexa8.addNode(10,  0,  0, 7)
hexa8.addNode(10, 10,  0, 8)
hexa8.addVolume([1, 2, 3, 4, 5, 6, 7, 8])
print(hexa8)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "hexa8")
obj.FemMesh = hexa8
obj.Placement.Base = FreeCAD.Vector(60, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"

Add a volume with the element number.

elemhexa8 = Fem.FemMesh()
nodes = hexa8.Nodes
for n in nodes:
    elemhexa8.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elemhexa8.addVolume([1,  2,  3, 4, 5, 6, 7, 8], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemhexa8")
obj.FemMesh = elemhexa8
obj.Placement.Base = FreeCAD.Vector(260, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
print(elemhexa8.Volumes)

Volume, 20 node hexahedron, hexa20 (quadratic)

import Fem

hexa20 = Fem.FemMesh()
hexa20.addNode( 0, 10, 10,  1)
hexa20.addNode( 0,  0, 10,  2)
hexa20.addNode(10,  0, 10,  3)
hexa20.addNode(10, 10, 10,  4)
hexa20.addNode( 0, 10,  0,  5)
hexa20.addNode( 0,  0,  0,  6)
hexa20.addNode(10,  0,  0,  7)
hexa20.addNode(10, 10,  0,  8)

hexa20.addNode( 0,  5, 10,  9)
hexa20.addNode( 5,  0, 10, 10)
hexa20.addNode(10,  5, 10, 11)
hexa20.addNode( 5, 10, 10, 12)

hexa20.addNode( 0,  5,  0, 13)
hexa20.addNode( 5,  0,  0, 14)
hexa20.addNode(10,  5,  0, 15)
hexa20.addNode( 5, 10,  0, 16)

hexa20.addNode( 0, 10,  5, 17)
hexa20.addNode( 0,  0,  5, 18)
hexa20.addNode(10,  0,  5, 19)
hexa20.addNode(10, 10,  5, 20)
hexa20.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20])
print(hexa20)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "hexa20")
obj.FemMesh = hexa20
obj.Placement.Base = FreeCAD.Vector(90, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"

Add a volume with the element number.

elemhexa20 = Fem.FemMesh()
nodes = hexa20.Nodes
for n in nodes:
    elemhexa20.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elemhexa20.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elemhexa20")
obj.FemMesh = elemhexa20
obj.Placement.Base = FreeCAD.Vector(290, 50, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
print(elemhexa20.Volumes)

Volume, 6 node pentahedron, penta6 (linear)

import Fem

penta6 = Fem.FemMesh()
penta6.addNode(10, 10, 10, 1)
penta6.addNode( 0,  0, 10, 2)
penta6.addNode(20,  0, 10, 3)
penta6.addNode(10, 10,  0, 4)
penta6.addNode( 0,  0,  0, 5)
penta6.addNode(20,  0,  0, 6)
penta6.addVolume([1, 2, 3, 4, 5, 6])
print(penta6)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "penta6")
obj.FemMesh = penta6
obj.Placement.Base = FreeCAD.Vector(0, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"

Add a volume with the element number.

elempenta6 = Fem.FemMesh()
nodes = penta6.Nodes
for n in nodes:
    elempenta6.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elempenta6.addVolume([ 1, 2, 3, 4, 5, 6], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elempenta6")
obj.FemMesh = elempenta6
obj.Placement.Base = FreeCAD.Vector(200, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
print(elempenta6.Volumes)

Volume, 15 node pentahedron, penta15 (quadratic)

import Fem

penta15 = Fem.FemMesh()
penta15.addNode(10, 10, 10,  1)
penta15.addNode( 0,  0, 10,  2)
penta15.addNode(20,  0, 10,  3)
penta15.addNode(10, 10,  0,  4)
penta15.addNode( 0,  0,  0,  5)
penta15.addNode(20,  0,  0,  6)

penta15.addNode( 5,  5, 10,  7)
penta15.addNode(10,  0, 10,  8)
penta15.addNode(15,  5, 10,  9)

penta15.addNode( 5,  5,  0, 10)
penta15.addNode(10,  0,  0, 11)
penta15.addNode(15,  5,  0, 12)

penta15.addNode(10, 10,  5, 13)
penta15.addNode( 0,  0,  5, 14)
penta15.addNode(20,  0,  5, 15)
penta15.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15])
print(penta15)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "penta15")
obj.FemMesh = penta15
obj.Placement.Base = FreeCAD.Vector(40, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"

Add a volume with the element number.

elempenta15 = Fem.FemMesh()
nodes = penta15.Nodes
for n in nodes:
    elempenta15.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elempenta15.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elempenta15")
obj.FemMesh = elempenta15
obj.Placement.Base = FreeCAD.Vector(240, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
print(elempenta15.Volumes)

Volume, 5 node pyramid, pyra5 (linear)

import Fem

pyra5 = Fem.FemMesh()
pyra5.addNode( 0, 20,  0, 1)
pyra5.addNode(20, 20,  0, 2)
pyra5.addNode(20,  0,  0, 3)
pyra5.addNode( 0,  0,  0, 4)
pyra5.addNode(10, 10, 10, 5)
pyra5.addVolume([1, 2, 3, 4, 5])
print(pyra5)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "pyra5")
obj.FemMesh = pyra5
obj.Placement.Base = FreeCAD.Vector(80, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"

Add a volume with the element number.

elempyra5 = Fem.FemMesh()
nodes = pyra5.Nodes
for n in nodes:
    elempyra5.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elempyra5.addVolume([1, 2, 3, 4, 5], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elempyra5")
obj.FemMesh = elempyra5
obj.Placement.Base = FreeCAD.Vector(280, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
print(elempyra5.Volumes)

Volume, 13 node pyramid, pyra13 (quadratic)

import Fem

pyra13 = Fem.FemMesh()
pyra13.addNode( 0, 20,  0,  1)
pyra13.addNode(20, 20,  0,  2)
pyra13.addNode(20,  0,  0,  3)
pyra13.addNode( 0,  0,  0,  4)
pyra13.addNode(10, 10, 10,  5)

pyra13.addNode(10, 20,  0,  6)
pyra13.addNode(20, 10,  0,  7)
pyra13.addNode(10,  0,  0,  8)
pyra13.addNode( 0, 10,  0,  9)

pyra13.addNode( 5, 15,  5, 10)
pyra13.addNode(15, 15,  5, 11)
pyra13.addNode(15,  5,  5, 12)
pyra13.addNode( 5,  5,  5, 13)
pyra13.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13])
print(pyra13)

obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "pyra13")
obj.FemMesh = pyra13
obj.Placement.Base = FreeCAD.Vector(120, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"

Add a volume with the element number.

elempyra13 = Fem.FemMesh()
nodes = pyra13.Nodes
for n in nodes:
    elempyra13.addNode(nodes[n].x, nodes[n].y, nodes[n].z, n)

elempyra13.addVolume([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13], 88)
obj = App.ActiveDocument.addObject("Fem::FemMeshObject", "elempyra13")
obj.FemMesh = elempyra13
obj.Placement.Base = FreeCAD.Vector(320, 0, 0)
obj.ViewObject.DisplayMode = "Faces, Wireframe & Nodes"
print(elempyra13.Volumes)

Scripting examples for groups

See for example https://forum.freecadweb.org/viewtopic.php?f=18&t=37304&start=20#p318823