FEM Tutorial Python

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Topic
Tutorial
Finite Element Analysis
Level
Intermediate
Time to complete
30 minutes
Authors
Bernd
FreeCAD version
0.18.15985 or above
Example files

See also
None
Contents 1 Introduction 1.1 Requirements 2 Let's start 2.1 New document and the part to analyze 2.2 Analysis and analysis objects 2.3 FEM mesh (manual) 2.4 FEM mesh (gmsh) 2.5 FEM mesh (netgen) 2.6 Recompute 3 Run the analysis 3.1 All in one 3.2 Step by step 4 Show the results 4.1 Additional Information 4.1.1 Scripting FEM mesh objects 4.1.1.1 Netgen 4.1.1.2 GMSH 4.1.2 Scripting multiple analysis 4.1.3 Scripting results 4.1.3.1 Standard FreeCAD result object 4.1.3.2 Vtk result object 4.1.4 Console mode 5 Appendix

Introduction

This tutorial is meant to show how a simple Finite Element Analysis (FEA) in FreeCAD's FEM Workbench is done using Python. The model from the FEM CalculiX Cantilever 3D tutorial will be used for this example.

Requirements

The compatible version of FreeCAD as designated in the tutorial overview.
Use the Help → About FreeCAD to see the version of FreeCAD that is installed.
Impotant Note: Due to the continuous development of the FEM Workbench it is recommended to use the latest development snapshot of FreeCAD especially for Python scripted FEM analyses.
A working FEM workbench. Run the FEM CalculiX Cantilever 3D analysis to ascertain this.

Let's start

New document and the part to analyze

# new document
doc = App.newDocument("Scripted_CalculiX_Cantilever3D")

# part
import Part
box_obj = doc.addObject('Part::Box', 'Box')
box_obj.Height = box_obj.Width = 1000
box_obj.Length = 8000

# see how our part looks like
import FreeCADGui
FreeCADGui.ActiveDocument.activeView().viewAxonometric()
FreeCADGui.SendMsgToActiveView("ViewFit")

#

Analysis and analysis objects

# let us create some objects

# import to create objects
import ObjectsFem

# analysis
analysis_object = ObjectsFem.makeAnalysis(doc, "Analysis")

# solver (we gone use the well tested CcxTools solver object)
solver_object = ObjectsFem.makeSolverCalculixCcxTools(doc, "CalculiX")
solver_object.GeometricalNonlinearity = 'linear'
solver_object.ThermoMechSteadyState = True
solver_object.MatrixSolverType = 'default'
solver_object.IterationsControlParameterTimeUse = False
analysis_object.addObject(solver_object)

# material
material_object = ObjectsFem.makeMaterialSolid(doc, "SolidMaterial")
mat = material_object.Material
mat['Name'] = "Steel-Generic"
mat['YoungsModulus'] = "210000 MPa"
mat['PoissonRatio'] = "0.30"
mat['Density'] = "7900 kg/m^3"
material_object.Material = mat
analysis_object.addObject(material_object)

# fixed_constraint
fixed_constraint = ObjectsFem.makeConstraintFixed(doc, "FemConstraintFixed")
fixed_constraint.References = [(doc.Box, "Face1")]
analysis_object.addObject(fixed_constraint)

# force_constraint
force_constraint = ObjectsFem.makeConstraintForce(doc, "FemConstraintForce")
force_constraint.References = [(doc.Box, "Face2")]
force_constraint.Force = 9000000.0
force_constraint.Direction = (doc.Box, ["Edge5"])
force_constraint.Reversed = True
analysis_object.addObject(force_constraint)

FEM mesh (manual)

This section contains the FEM mesh code. Please expand it to view the contents.

Note: Check out the Additional Information section below for how to script mesh generation with GMSH or Netgen mesh object.

# mesh
import Fem
femmesh = Fem.FemMesh()

# nodes
femmesh.addNode(8000.0, 1000.0, 0.0, 1)
femmesh.addNode(8000.0, 1000.0, 1000.0, 2)
femmesh.addNode(8000.0, 0.0, 0.0, 3)
femmesh.addNode(8000.0, 0.0, 1000.0, 4)
femmesh.addNode(0.0, 1000.0, 0.0, 5)
femmesh.addNode(0.0, 1000.0, 1000.0, 6)
femmesh.addNode(0.0, 0.0, 0.0, 7)
femmesh.addNode(0.0, 0.0, 1000.0, 8)
femmesh.addNode(728.0, 1000.0, 1000.0, 9)
femmesh.addNode(1456.0, 1000.0, 1000.0, 10)
femmesh.addNode(2184.0, 1000.0, 1000.0, 11)
femmesh.addNode(2912.0, 1000.0, 1000.0, 12)
femmesh.addNode(3640.0, 1000.0, 1000.0, 13)
femmesh.addNode(4368.0, 1000.0, 1000.0, 14)
femmesh.addNode(5096.0, 1000.0, 1000.0, 15)
femmesh.addNode(5824.0, 1000.0, 1000.0, 16)
femmesh.addNode(6552.0, 1000.0, 1000.0, 17)
femmesh.addNode(7280.0, 1000.0, 1000.0, 18)
femmesh.addNode(728.0, 0.0, 1000.0, 19)
femmesh.addNode(1456.0, 0.0, 1000.0, 20)
femmesh.addNode(2184.0, 0.0, 1000.0, 21)
femmesh.addNode(2912.0, 0.0, 1000.0, 22)
femmesh.addNode(3640.0, 0.0, 1000.0, 23)
femmesh.addNode(4368.0, 0.0, 1000.0, 24)
femmesh.addNode(5096.0, 0.0, 1000.0, 25)
femmesh.addNode(5824.0, 0.0, 1000.0, 26)
femmesh.addNode(6552.0, 0.0, 1000.0, 27)
femmesh.addNode(7280.0, 0.0, 1000.0, 28)
femmesh.addNode(728.0, 1000.0, 0.0, 29)
femmesh.addNode(1456.0, 1000.0, 0.0, 30)
femmesh.addNode(2184.0, 1000.0, 0.0, 31)
femmesh.addNode(2912.0, 1000.0, 0.0, 32)
femmesh.addNode(3640.0, 1000.0, 0.0, 33)
femmesh.addNode(4368.0, 1000.0, 0.0, 34)
femmesh.addNode(5096.0, 1000.0, 0.0, 35)
femmesh.addNode(5824.0, 1000.0, 0.0, 36)
femmesh.addNode(6552.0, 1000.0, 0.0, 37)
femmesh.addNode(7280.0, 1000.0, 0.0, 38)
femmesh.addNode(728.0, 0.0, 0.0, 39)
femmesh.addNode(1456.0, 0.0, 0.0, 40)
femmesh.addNode(2184.0, 0.0, 0.0, 41)
femmesh.addNode(2912.0, 0.0, 0.0, 42)
femmesh.addNode(3640.0, 0.0, 0.0, 43)
femmesh.addNode(4368.0, 0.0, 0.0, 44)
femmesh.addNode(5096.0, 0.0, 0.0, 45)
femmesh.addNode(5824.0, 0.0, 0.0, 46)
femmesh.addNode(6552.0, 0.0, 0.0, 47)
femmesh.addNode(7280.0, 0.0, 0.0, 48)
femmesh.addNode(8000.0, 500.0, 500.0, 49)
femmesh.addNode(0.0, 500.0, 500.0, 50)
femmesh.addNode(4731.99999977, 500.000001086, 499.999998599, 51)
femmesh.addNode(0.0, 500.0, 1000.0, 52)
femmesh.addNode(364.0, 1000.0, 1000.0, 53)
femmesh.addNode(1092.0, 1000.0, 1000.0, 54)
femmesh.addNode(1820.0, 1000.0, 1000.0, 55)
femmesh.addNode(2548.0, 1000.0, 1000.0, 56)
femmesh.addNode(3276.0, 1000.0, 1000.0, 57)
femmesh.addNode(4004.0, 1000.0, 1000.0, 58)
femmesh.addNode(4732.0, 1000.0, 1000.0, 59)
femmesh.addNode(5460.0, 1000.0, 1000.0, 60)
femmesh.addNode(6188.0, 1000.0, 1000.0, 61)
femmesh.addNode(6916.0, 1000.0, 1000.0, 62)
femmesh.addNode(7640.0, 1000.0, 1000.0, 63)
femmesh.addNode(8000.0, 500.0, 1000.0, 64)
femmesh.addNode(364.0, 0.0, 1000.0, 65)
femmesh.addNode(1092.0, 0.0, 1000.0, 66)
femmesh.addNode(1820.0, 0.0, 1000.0, 67)
femmesh.addNode(2548.0, 0.0, 1000.0, 68)
femmesh.addNode(3276.0, 0.0, 1000.0, 69)
femmesh.addNode(4004.0, 0.0, 1000.0, 70)
femmesh.addNode(4732.0, 0.0, 1000.0, 71)
femmesh.addNode(5460.0, 0.0, 1000.0, 72)
femmesh.addNode(6188.0, 0.0, 1000.0, 73)
femmesh.addNode(6916.0, 0.0, 1000.0, 74)
femmesh.addNode(7640.0, 0.0, 1000.0, 75)
femmesh.addNode(0.0, 500.0, 0.0, 76)
femmesh.addNode(364.0, 1000.0, 0.0, 77)
femmesh.addNode(1092.0, 1000.0, 0.0, 78)
femmesh.addNode(1820.0, 1000.0, 0.0, 79)
femmesh.addNode(2548.0, 1000.0, 0.0, 80)
femmesh.addNode(3276.0, 1000.0, 0.0, 81)
femmesh.addNode(4004.0, 1000.0, 0.0, 82)
femmesh.addNode(4732.0, 1000.0, 0.0, 83)
femmesh.addNode(5460.0, 1000.0, 0.0, 84)
femmesh.addNode(6188.0, 1000.0, 0.0, 85)
femmesh.addNode(6916.0, 1000.0, 0.0, 86)
femmesh.addNode(7640.0, 1000.0, 0.0, 87)
femmesh.addNode(8000.0, 500.0, 0.0, 88)
femmesh.addNode(364.0, 0.0, 0.0, 89)
femmesh.addNode(1092.0, 0.0, 0.0, 90)
femmesh.addNode(1820.0, 0.0, 0.0, 91)
femmesh.addNode(2548.0, 0.0, 0.0, 92)
femmesh.addNode(3276.0, 0.0, 0.0, 93)
femmesh.addNode(4004.0, 0.0, 0.0, 94)
femmesh.addNode(4732.0, 0.0, 0.0, 95)
femmesh.addNode(5460.0, 0.0, 0.0, 96)
femmesh.addNode(6188.0, 0.0, 0.0, 97)
femmesh.addNode(6916.0, 0.0, 0.0, 98)
femmesh.addNode(7640.0, 0.0, 0.0, 99)
femmesh.addNode(8000.0, 1000.0, 500.0, 100)
femmesh.addNode(0.0, 1000.0, 500.0, 101)
femmesh.addNode(8000.0, 0.0, 500.0, 102)
femmesh.addNode(0.0, 0.0, 500.0, 103)
femmesh.addNode(364.0, 500.0, 1000.0, 104)
femmesh.addNode(728.0, 500.0, 1000.0, 105)
femmesh.addNode(1092.0, 500.0, 1000.0, 106)
femmesh.addNode(1456.0, 500.0, 1000.0, 107)
femmesh.addNode(1820.0, 500.0, 1000.0, 108)
femmesh.addNode(2184.0, 500.0, 1000.0, 109)
femmesh.addNode(2548.0, 500.0, 1000.0, 110)
femmesh.addNode(3276.0, 500.0, 1000.0, 111)
femmesh.addNode(3640.0, 500.0, 1000.0, 112)
femmesh.addNode(4004.0, 500.0, 1000.0, 113)
femmesh.addNode(4368.0, 500.0, 1000.0, 114)
femmesh.addNode(4732.0, 500.0, 1000.0, 115)
femmesh.addNode(5096.0, 500.0, 1000.0, 116)
femmesh.addNode(5460.0, 500.0, 1000.0, 117)
femmesh.addNode(5824.0, 500.0, 1000.0, 118)
femmesh.addNode(6188.0, 500.0, 1000.0, 119)
femmesh.addNode(6552.0, 500.0, 1000.0, 120)
femmesh.addNode(6916.0, 500.0, 1000.0, 121)
femmesh.addNode(7640.0, 500.0, 1000.0, 122)
femmesh.addNode(2912.0, 500.0, 1000.0, 123)
femmesh.addNode(7280.0, 500.0, 1000.0, 124)
femmesh.addNode(364.0, 500.0, 0.0, 125)
femmesh.addNode(1092.0, 500.0, 0.0, 126)
femmesh.addNode(728.0, 500.0, 0.0, 127)
femmesh.addNode(1820.0, 500.0, 0.0, 128)
femmesh.addNode(1456.0, 500.0, 0.0, 129)
femmesh.addNode(2548.0, 500.0, 0.0, 130)
femmesh.addNode(2184.0, 500.0, 0.0, 131)
femmesh.addNode(3640.0, 500.0, 0.0, 132)
femmesh.addNode(3276.0, 500.0, 0.0, 133)
femmesh.addNode(4004.0, 500.0, 0.0, 134)
femmesh.addNode(5096.0, 500.0, 0.0, 135)
femmesh.addNode(4732.0, 500.0, 0.0, 136)
femmesh.addNode(5460.0, 500.0, 0.0, 137)
femmesh.addNode(6188.0, 500.0, 0.0, 138)
femmesh.addNode(5824.0, 500.0, 0.0, 139)
femmesh.addNode(6916.0, 500.0, 0.0, 140)
femmesh.addNode(6552.0, 500.0, 0.0, 141)
femmesh.addNode(7640.0, 500.0, 0.0, 142)
femmesh.addNode(2912.0, 500.0, 0.0, 143)
femmesh.addNode(4368.0, 500.0, 0.0, 144)
femmesh.addNode(7280.0, 500.0, 0.0, 145)
femmesh.addNode(364.0, 1000.0, 500.0, 146)
femmesh.addNode(728.0, 1000.0, 500.0, 147)
femmesh.addNode(1092.0, 1000.0, 500.0, 148)
femmesh.addNode(1456.0, 1000.0, 500.0, 149)
femmesh.addNode(1820.0, 1000.0, 500.0, 150)
femmesh.addNode(2184.0, 1000.0, 500.0, 151)
femmesh.addNode(2548.0, 1000.0, 500.0, 152)
femmesh.addNode(3276.0, 1000.0, 500.0, 153)
femmesh.addNode(3640.0, 1000.0, 500.0, 154)
femmesh.addNode(4004.0, 1000.0, 500.0, 155)
femmesh.addNode(4368.0, 1000.0, 500.0, 156)
femmesh.addNode(4732.0, 1000.0, 500.0, 157)
femmesh.addNode(5096.0, 1000.0, 500.0, 158)
femmesh.addNode(5460.0, 1000.0, 500.0, 159)
femmesh.addNode(5824.0, 1000.0, 500.0, 160)
femmesh.addNode(6188.0, 1000.0, 500.0, 161)
femmesh.addNode(6552.0, 1000.0, 500.0, 162)
femmesh.addNode(6916.0, 1000.0, 500.0, 163)
femmesh.addNode(7640.0, 1000.0, 500.0, 164)
femmesh.addNode(2912.0, 1000.0, 500.0, 165)
femmesh.addNode(7280.0, 1000.0, 500.0, 166)
femmesh.addNode(364.0, 0.0, 500.0, 167)
femmesh.addNode(1092.0, 0.0, 500.0, 168)
femmesh.addNode(728.0, 0.0, 500.0, 169)
femmesh.addNode(1820.0, 0.0, 500.0, 170)
femmesh.addNode(1456.0, 0.0, 500.0, 171)
femmesh.addNode(2548.0, 0.0, 500.0, 172)
femmesh.addNode(2184.0, 0.0, 500.0, 173)
femmesh.addNode(3640.0, 0.0, 500.0, 174)
femmesh.addNode(3276.0, 0.0, 500.0, 175)
femmesh.addNode(4004.0, 0.0, 500.0, 176)
femmesh.addNode(5096.0, 0.0, 500.0, 177)
femmesh.addNode(4732.0, 0.0, 500.0, 178)
femmesh.addNode(5460.0, 0.0, 500.0, 179)
femmesh.addNode(6188.0, 0.0, 500.0, 180)
femmesh.addNode(5824.0, 0.0, 500.0, 181)
femmesh.addNode(6916.0, 0.0, 500.0, 182)
femmesh.addNode(6552.0, 0.0, 500.0, 183)
femmesh.addNode(7640.0, 0.0, 500.0, 184)
femmesh.addNode(2912.0, 0.0, 500.0, 185)
femmesh.addNode(4368.0, 0.0, 500.0, 186)
femmesh.addNode(7280.0, 0.0, 500.0, 187)
femmesh.addNode(8000.0, 250.0, 250.0, 188)
femmesh.addNode(8000.0, 250.0, 750.0, 189)
femmesh.addNode(8000.0, 750.0, 750.0, 190)
femmesh.addNode(8000.0, 750.0, 250.0, 191)
femmesh.addNode(0.0, 250.0, 750.0, 192)
femmesh.addNode(0.0, 250.0, 250.0, 193)
femmesh.addNode(0.0, 750.0, 250.0, 194)
femmesh.addNode(0.0, 750.0, 750.0, 195)
femmesh.addNode(1456.0, 500.0, 500.0, 196)
femmesh.addNode(6552.0, 500.0, 500.0, 197)
femmesh.addNode(6916.0, 500.0, 500.0, 198)
femmesh.addNode(2184.0, 500.0, 500.0, 199)
femmesh.addNode(2548.0, 500.0, 500.0, 200)
femmesh.addNode(2912.0, 500.0, 500.0, 201)
femmesh.addNode(1820.0, 500.0, 500.0, 202)
femmesh.addNode(7640.0, 750.0, 250.0, 203)
femmesh.addNode(7640.0, 750.0, 750.0, 204)
femmesh.addNode(7280.0, 500.0, 500.0, 205)
femmesh.addNode(7640.0, 250.0, 250.0, 206)
femmesh.addNode(5460.0, 500.0, 500.0, 207)
femmesh.addNode(5096.0, 500.0, 500.0, 208)
femmesh.addNode(6188.0, 500.0, 500.0, 209)
femmesh.addNode(5824.0, 500.0, 500.0, 210)
femmesh.addNode(364.0, 750.0, 250.0, 211)
femmesh.addNode(364.0, 750.0, 750.0, 212)
femmesh.addNode(364.0, 250.0, 250.0, 213)
femmesh.addNode(1092.0, 500.0, 500.0, 214)
femmesh.addNode(728.0, 500.0, 500.0, 215)
femmesh.addNode(364.0, 250.0, 750.0, 216)
femmesh.addNode(4549.99999989, 250.000000543, 249.9999993, 217)
femmesh.addNode(4549.99999989, 750.000000543, 249.9999993, 218)
femmesh.addNode(4549.99999989, 750.000000543, 749.9999993, 219)
femmesh.addNode(4368.0, 500.0, 500.0, 220)
femmesh.addNode(4549.99999989, 250.000000543, 749.9999993, 221)
femmesh.addNode(4913.99999989, 250.000000543, 749.9999993, 222)
femmesh.addNode(4913.99999989, 750.000000543, 749.9999993, 223)
femmesh.addNode(3276.0, 500.0, 500.0, 224)
femmesh.addNode(3640.0, 500.0, 500.0, 225)
femmesh.addNode(4004.0, 500.0, 500.0, 226)
femmesh.addNode(4913.99999989, 750.000000543, 249.9999993, 227)
femmesh.addNode(4913.99999989, 250.000000543, 249.9999993, 228)

# elements
femmesh.addVolume([40, 19, 10, 20, 168, 106, 196, 171, 66, 107], 149)
femmesh.addVolume([10, 31, 30, 40, 150, 79, 149, 196, 128, 129], 150)
femmesh.addVolume([38, 17, 18, 47, 163, 62, 166, 140, 197, 198], 151)
femmesh.addVolume([32, 41, 11, 12, 130, 199, 152, 165, 200, 56], 152)
femmesh.addVolume([12, 32, 41, 42, 165, 130, 200, 201, 143, 92], 153)
femmesh.addVolume([42, 21, 12, 22, 172, 110, 201, 185, 68, 123], 154)
femmesh.addVolume([10, 31, 40, 11, 150, 128, 196, 55, 151, 202], 155)
femmesh.addVolume([11, 12, 41, 21, 56, 200, 199, 109, 110, 173], 156)
femmesh.addVolume([20, 41, 11, 40, 170, 199, 108, 171, 91, 202], 157)
femmesh.addVolume([20, 41, 21, 11, 170, 173, 67, 108, 199, 109], 158)
femmesh.addVolume([32, 11, 41, 31, 152, 199, 130, 80, 151, 131], 159)
femmesh.addVolume([11, 10, 20, 40, 55, 107, 108, 202, 196, 171], 160)
femmesh.addVolume([38, 17, 47, 37, 163, 197, 140, 86, 162, 141], 161)
femmesh.addVolume([38, 18, 49, 48, 166, 204, 203, 145, 205, 206], 162)
femmesh.addVolume([46, 15, 45, 36, 207, 208, 96, 139, 159, 137], 163)
femmesh.addVolume([47, 16, 46, 37, 209, 210, 97, 141, 161, 138], 164)
femmesh.addVolume([18, 4, 2, 49, 122, 64, 63, 204, 189, 190], 165)
femmesh.addVolume([18, 17, 27, 47, 62, 120, 121, 198, 197, 183], 166)
femmesh.addVolume([38, 18, 48, 47, 166, 205, 145, 140, 198, 98], 167)
femmesh.addVolume([12, 23, 42, 22, 111, 175, 201, 123, 69, 185], 168)
femmesh.addVolume([26, 47, 27, 17, 180, 183, 73, 119, 197, 120], 169)
femmesh.addVolume([50, 29, 9, 6, 211, 147, 212, 195, 146, 53], 170)
femmesh.addVolume([27, 48, 18, 47, 182, 205, 121, 183, 98, 198], 171)
femmesh.addVolume([8, 7, 39, 50, 103, 89, 167, 192, 193, 213], 172)
femmesh.addVolume([40, 9, 39, 30, 214, 215, 90, 129, 148, 126], 173)
femmesh.addVolume([42, 21, 41, 12, 172, 173, 92, 201, 110, 200], 174)
femmesh.addVolume([50, 9, 29, 39, 212, 147, 211, 213, 215, 127], 175)
femmesh.addVolume([29, 7, 50, 39, 125, 193, 211, 127, 89, 213], 176)
femmesh.addVolume([31, 11, 41, 40, 151, 199, 131, 128, 202, 91], 177)
femmesh.addVolume([47, 16, 37, 17, 209, 161, 141, 197, 61, 162], 178)
femmesh.addVolume([40, 9, 30, 10, 214, 148, 129, 196, 54, 149], 179)
femmesh.addVolume([2, 38, 49, 1, 164, 203, 190, 100, 87, 191], 180)
femmesh.addVolume([2, 38, 18, 49, 164, 166, 63, 190, 203, 204], 181)
femmesh.addVolume([48, 49, 38, 3, 206, 203, 145, 99, 188, 142], 182)
femmesh.addVolume([38, 49, 1, 3, 203, 191, 87, 142, 188, 88], 183)
femmesh.addVolume([49, 4, 3, 48, 189, 102, 188, 206, 184, 99], 184)
femmesh.addVolume([28, 48, 4, 18, 187, 184, 75, 124, 205, 122], 185)
femmesh.addVolume([49, 18, 4, 48, 204, 122, 189, 206, 205, 184], 186)
femmesh.addVolume([7, 50, 5, 29, 193, 194, 76, 125, 211, 77], 187)
femmesh.addVolume([50, 6, 5, 29, 195, 101, 194, 211, 146, 77], 188)
femmesh.addVolume([50, 9, 19, 6, 212, 105, 216, 195, 53, 104], 189)
femmesh.addVolume([50, 19, 9, 39, 216, 105, 212, 213, 169, 215], 190)
femmesh.addVolume([50, 19, 8, 6, 216, 65, 192, 195, 104, 52], 191)
femmesh.addVolume([40, 9, 10, 19, 214, 54, 196, 168, 105, 106], 192)
femmesh.addVolume([51, 44, 34, 14, 217, 144, 218, 219, 220, 156], 193)
femmesh.addVolume([51, 24, 44, 14, 221, 186, 217, 219, 114, 220], 194)
femmesh.addVolume([25, 15, 24, 51, 116, 115, 71, 222, 223, 221], 195)
femmesh.addVolume([43, 12, 32, 13, 224, 165, 133, 225, 57, 153], 196)
femmesh.addVolume([43, 12, 23, 42, 224, 111, 174, 93, 201, 175], 197)
femmesh.addVolume([43, 12, 13, 23, 224, 57, 225, 174, 111, 112], 198)
femmesh.addVolume([43, 12, 42, 32, 224, 201, 93, 133, 165, 143], 199)
femmesh.addVolume([34, 13, 14, 44, 155, 58, 156, 144, 226, 220], 200)
femmesh.addVolume([14, 24, 15, 51, 114, 115, 59, 219, 221, 223], 201)
femmesh.addVolume([23, 24, 14, 44, 70, 114, 113, 176, 186, 220], 202)
femmesh.addVolume([33, 32, 13, 43, 81, 153, 154, 132, 133, 225], 203)
femmesh.addVolume([34, 33, 13, 43, 82, 154, 155, 134, 132, 225], 204)
femmesh.addVolume([35, 14, 15, 51, 157, 59, 158, 227, 219, 223], 205)
femmesh.addVolume([25, 45, 15, 51, 177, 208, 116, 222, 228, 223], 206)
femmesh.addVolume([44, 43, 13, 23, 94, 225, 226, 176, 174, 112], 207)
femmesh.addVolume([35, 34, 14, 51, 83, 156, 157, 227, 218, 219], 208)
femmesh.addVolume([46, 15, 36, 16, 207, 159, 139, 210, 60, 160], 209)
femmesh.addVolume([36, 35, 15, 45, 84, 158, 159, 137, 135, 208], 210)
femmesh.addVolume([37, 36, 16, 46, 85, 160, 161, 138, 139, 210], 211)
femmesh.addVolume([25, 26, 16, 46, 72, 118, 117, 179, 181, 210], 212)
femmesh.addVolume([47, 16, 17, 26, 209, 61, 197, 180, 118, 119], 213)
femmesh.addVolume([47, 16, 26, 46, 209, 118, 180, 97, 210, 181], 214)
femmesh.addVolume([27, 28, 18, 48, 74, 124, 121, 182, 187, 205], 215)
femmesh.addVolume([35, 34, 51, 45, 83, 218, 227, 135, 136, 228], 216)
femmesh.addVolume([13, 14, 44, 23, 58, 220, 226, 112, 113, 176], 217)
femmesh.addVolume([44, 25, 24, 51, 178, 71, 186, 217, 222, 221], 218)
femmesh.addVolume([44, 45, 25, 51, 95, 177, 178, 217, 228, 222], 219)
femmesh.addVolume([46, 15, 16, 25, 207, 60, 210, 179, 116, 117], 220)
femmesh.addVolume([46, 15, 25, 45, 207, 116, 179, 96, 208, 177], 221)
femmesh.addVolume([50, 8, 19, 39, 192, 65, 216, 213, 167, 169], 222)
femmesh.addVolume([35, 51, 15, 45, 227, 223, 158, 135, 228, 208], 223)
femmesh.addVolume([34, 44, 43, 13, 144, 94, 134, 155, 226, 225], 224)
femmesh.addVolume([51, 44, 45, 34, 217, 95, 228, 218, 144, 136], 225)
femmesh.addVolume([9, 29, 39, 30, 147, 127, 215, 148, 78, 126], 226)
femmesh.addVolume([40, 9, 19, 39, 214, 105, 168, 90, 215, 169], 227)

# add it to the analysis
femmesh_obj = doc.addObject('Fem::FemMeshObject', 'Box_Mesh')
femmesh_obj.FemMesh = femmesh
analysis_object.addObject(femmesh_obj)

FEM mesh (gmsh)

femmesh_obj = ObjectsFem.makeMeshGmsh(doc, box_obj.Name + "_Mesh")
femmesh_obj.Part = doc.Box

doc.recompute()

from femmesh.gmshtools import GmshTools as gt
gmsh_mesh = gt(femmesh_obj)
error = gmsh_mesh.create_mesh()
print(error)

analysis_object.addObject(femmesh_obj)

FEM mesh (netgen)

mesh = doc.addObject('Fem::FemMeshShapeNetgenObject', 'FEMMeshNetgen')
mesh.Shape = doc.Box
mesh.MaxSize = 1000
mesh.Fineness = "Moderate"
mesh.Optimize = True
mesh.SecondOrder = True
doc.recompute()

analysis_object.addObject(mesh)

Recompute

# recompute
doc.recompute()

###

Run the analysis

To run the analysis using Python, an instance of the ccxtools module class FemToolsCcx needs to be created. Once this instance has been created, we have two choices when running the analysis:

Run all processes together at once (see "All in one" section below)
Run processes one after the other (see "Step by step" section below)

If there is only one analysis in the document and only one solver in the analysis, then no objects need to be passed on fea init. The init method of the fea class will activate the analysis if the GUI is up.

Activating an analysis using Python works a follows:

# activating analysis
import FemGui
FemGui.setActiveAnalysis(doc.Analysis)

###

All in one

# run the analysis all in one
from femtools import ccxtools
fea = ccxtools.FemToolsCcx()
fea.purge_results()
fea.run()

###

Step by step

# run the analysis step by step
from femtools import ccxtools
fea = ccxtools.FemToolsCcx()
fea.update_objects()
fea.setup_working_dir()
fea.setup_ccx()
message = fea.check_prerequisites()
if not message:
    fea.purge_results()
    fea.write_inp_file()
    # on error at inp file writing, the inp file path "" was returned (even if the file was written)
    # if we would write the inp file anyway, we need to again set it manually
    # fea.inp_file_name = '/tmp/FEMWB/FEMMeshGmsh.inp'
    fea.ccx_run()
    fea.load_results()
else:
    FreeCAD.Console.PrintError("Houston, we have a problem! {}\n".format(message))  # in report view
    print("Houston, we have a problem! {}\n".format(message))  # in Python console

###

Show the results

# show some results
for m in analysis_object.Group:
    if m.isDerivedFrom('Fem::FemResultObject'):
        result_object = m
        break

femmesh_obj.ViewObject.setNodeDisplacementByVectors(result_object.NodeNumbers, result_object.DisplacementVectors)
femmesh_obj.ViewObject.applyDisplacement(10)

###

Additional Information

Scripting FEM mesh objects

Netgen

Scripting the Netgen mesh object was attempted in the "Parametrized FEM study" (FreeCAD FEM subforum thread), but has some limitations.

GMSH

On the contrary, the GMSH mesh object fully supports Python scripting. See the following forum posts:

Scripting multiple analysis

See forum post: http://forum.freecadweb.org/viewtopic.php?f=18&t=19549#p151385

Scripting results

Standard FreeCAD result object

See forum posts:

https://forum.freecadweb.org/viewtopic.php?f=18&t=34048&p=289519#p289519 → scale factor in standard result object
http://forum.freecadweb.org/viewtopic.php?f=18&t=4677&start=20#p148982
http://forum.freecadweb.org/viewtopic.php?f=18&t=4677&start=30#p149043
http://forum.freecadweb.org/viewtopic.php?t=18415#p144028
https://forum.freecadweb.org/viewtopic.php?f=18&t=31123&p=258761#p258761 → coloring just one element
https://forum.freecadweb.org/viewtopic.php?f=18&t=41951&p=357687#p357685 → reset all result mesh, show colored displacement magnitude

Vtk result object

See forum posts:

https://forum.freecadweb.org/viewtopic.php?f=18&t=47227#p405406

Console mode

Writing the input file in FreeCAD console mode (no Gui) could be done in test mode. See this relevant forum post for more details and experimentation.