FEM Mesh
Create a finite element mesh[edit | edit source]
Finite element analysis (FEA) is performed on a mesh composed of multiple triangular/tetrahedral, quadrilateral/hexahedral or other finite elements that subdivide an original body. The more refined the mesh is, the more accurate the numerical results will be, but also the computation time will be larger. A balance between the size of the mesh, and computation time and accuracy of results is an important characteristic of a well defined finite element analysis.
There are different possibilities to set up a mesh in the FEM Workbench:
- The Gmsh tool from the graphical user interface.
- The Netgen tool from the graphical user interface.
- Importing a mesh from another program. In particular, Gmsh and Netgen can be used by themselves outside of FreeCAD to mesh solid bodies like Step files.
- Manually creating the mesh through Python scripting.
The Gmsh and Netgen tools support meshing bodies created with the Part Workbench and PartDesign Workbench, as well as simple copies of those solids. In general, any workbench that generates solid objects, like the BIM Workbench, can be used as the basis from which to create meshes. Notice that a mesh used for FEA is different from a mesh created or imported from the Mesh Workbench.
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[edit | edit source]
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[edit | edit source]
- Gmsh: main website, code repository
- Netgen: main website, code repository
No interface in FreeCAD[edit | edit source]
- ENigMA, forum thread, code repository
- libMesh, main website, code repository, forum thread; it's a very active project, and it's C++ only
- PythonOCC, main website
- SnappyHexMesh, main website
- Tetgen, main website
Mesh elements in FreeCAD[edit | edit source]
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.
- "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[edit | edit source]
More information on the elements, and their data structure inside FreeCAD can be found in FEM Element Types.
Segment element[edit | edit source]
Triangle element[edit | edit source]
Quadrangle element[edit | edit source]
Tetrahedron element[edit | edit source]
Hexahedron element[edit | edit source]
Pentahedron element (prism)[edit | edit source]
Pyramid element[edit | edit source]
Scripting[edit | edit source]
Create a FEM mesh completely in Python[edit | edit source]
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[edit | edit source]
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[edit | edit source]
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[edit | edit source]
Beam, 2 node line, seg2 (linear)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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)[edit | edit source]
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[edit | edit source]
See for example https://forum.freecad.org/viewtopic.php?f=18&t=37304&start=20#p318823
- Materials: Solid Material, Fluid Material, Non-Linear Mechanical Material, Reinforced Material (Concrete); Material Editor
- Element Geometry: Beam Cross Section, Beam Rotation, Shell Plate Thickness, Fluid Section for 1D Flow
- Electromagnetic Boundary Conditions: Electrostatic Potential Boundary Condition, Current Density Boundary Condition, Magnetization Boundary Condition, Electric Charge Density
- Fluid Boundary Conditions: Initial Flow Velocity Condition, Initial Pressure Condition, Flow Velocity Boundary Condition
- Geometrical Analysis Features: Plane Multi-Point Constraint, Section Print Feature, Local Coordinate System
- Mechanical Boundary Conditions and Loads: Fixed Boundary Condition, Rigid Body Constraint, Displacement Boundary Condition, Contact Constraint, Tie Constraint, Spring Boundary Condition, Force Load, Pressure Load, Centrifugal Load, Gravity Load
- Thermal Boundary Conditions and Loads: Initial Temperature, Heat Flux Load, Temperature Boundary Condition, Body Heat Source
- Overwrite Constants: Constant Vacuum Permittivity
- Mesh: Mesh From Shape by Netgen, Mesh From Shape by Gmsh, Mesh Boundary Layer, Mesh Refinement, Mesh Group, Erase Elements, FEM Mesh to Mesh
- Solve: Solver CalculiX, Solver Elmer, Solver Mystran, Solver Z88; Mechanical Equations: Elasticity Equation, Deformation Equation; Electromagnetic Equations: Electrostatic Equation, Electricforce Equation, Magnetodynamic Equation, Magnetodynamic 2D Equation, Static Current Equation; Flow Equation, Flux Equation, Heat Equation, Solver Job Control, Run Solver
- Results: Purge Results, Show Result, Apply Changes to Pipeline, Post Pipeline From Result, Pipeline Branch, Warp Filter, Scalar Clip Filter, Function Cut Filter, Region Clip Filter, Contours Filter, Glyph Filter, Line Clip Filter, Stress Linearization Plot, Data at Point Clip Filter, Calculator Filter; Filter Functions: Plane, Sphere, Cylinder, Box; Data Visualizations: Create Lineplot, Create Histogram, Create Table
- Utilities: Clipping Plane on Face, Remove All Clipping Planes, FEM Examples; Clear FEM Mesh, Display Mesh Info
- Additional: Preferences; FEM Install, FEM Mesh, FEM Solver, FEM CalculiX, FEM Concrete; FEM Element Types
- Getting started
- Installation: Download, Windows, Linux, Mac, Additional components, Docker, AppImage, Ubuntu Snap
- Basics: About FreeCAD, Interface, Mouse navigation, Selection methods, Object name, Preferences, Workbenches, Document structure, Properties, Help FreeCAD, Donate
- Help: Tutorials, Video tutorials
- Workbenches: Std Base, Assembly, BIM, CAM, Draft, FEM, Inspection, Material, Mesh, OpenSCAD, Part, PartDesign, Points, Reverse Engineering, Robot, Sketcher, Spreadsheet, Surface, TechDraw, Test Framework
- Hubs: User hub, Power users hub, Developer hub