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[FEM] add example for magnetostatics

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Uwe
2023-02-24 16:09:53 +01:00
parent 63cb23d1fd
commit 45eff3aaed
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1
src/Mod/Fem/CMakeLists.txt
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@@ -81,6 +81,7 @@ SET(FemExamples_SRCS
femexamples/equation_flux_elmer.py
femexamples/equation_magnetodynamics_elmer.py
femexamples/equation_magnetodynamics_2D_elmer.py
femexamples/equation_magnetostatics_2D_elmer.py
femexamples/frequency_beamsimple.py
femexamples/manager.py
femexamples/material_multiple_bendingbeam_fiveboxes.py

261
src/Mod/Fem/femexamples/equation_magnetostatics_2D_elmer.py Normal file
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@@ -0,0 +1,261 @@
# ***************************************************************************
# * Copyright (c) 2023 Uwe Stöhr <uwestoehr@lyx.org> *
# * *
# * This file is part of the FreeCAD CAx development system. *
# * *
# * This program is free software; you can redistribute it and/or modify *
# * it under the terms of the GNU Lesser General Public License (LGPL) *
# * as published by the Free Software Foundation; either version 2 of *
# * the License, or (at your option) any later version. *
# * for detail see the LICENCE text file. *
# * *
# * This program is distributed in the hope that it will be useful, *
# * but WITHOUT ANY WARRANTY; without even the implied warranty of *
# * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
# * GNU Library General Public License for more details. *
# * *
# * You should have received a copy of the GNU Library General Public *
# * License along with this program; if not, write to the Free Software *
# * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 *
# * USA *
# * *
# ***************************************************************************
import sys
import FreeCAD
from FreeCAD import Vector
import Draft
import ObjectsFem
import Part
from BOPTools import SplitFeatures
from . import manager
from .manager import get_meshname
from .manager import init_doc
def get_information():
return {
"name": "Magnetostatic - Elmer 2D",
"meshtype": "solid",
"meshelement": "Tet10",
"constraints": ["magnetization"],
"solvers": ["elmer"],
"material": "solid",
"equations": ["magnetostatic"]
}
def get_explanation(header=""):
return header + """
To run the example from Python console use:
from femexamples.equation_magnetostatics_2D_elmer import setup
setup()
Magnetodynamic2D equation - Elmer solver
"""
def setup(doc=None, solvertype="elmer"):
# init FreeCAD document
if doc is None:
doc = init_doc()
# explanation object
# just keep the following line and change text string in get_explanation method
manager.add_explanation_obj(doc, get_explanation(manager.get_header(get_information())))
# geometric objects
# wire defining the lower horse shoe end
p1 = Vector(0.0, -200.0, 0.0)
p2 = Vector(200.0, -200.0, 0.0)
p3 = Vector(200.0, -100.0, 0.0)
p4 = Vector(0.0, -100.0, 0.0)
Horseshoe_lower = Draft.make_wire([p1, p2, p3, p4], closed=True)
Horseshoe_lower.Label = "Lower_End"
Horseshoe_lower.ViewObject.Visibility = False
# wire defining the upper horse shoe end
p1 = Vector(0.0, 100.0, 0.0)
p2 = Vector(200.0, 100.0, 0.0)
p3 = Vector(200.0, 200.0, 0.0)
p4 = Vector(0.0, 200.0, 0.0)
Horseshoe_upper = Draft.make_wire([p1, p2, p3, p4], closed=True)
Horseshoe_upper.Label = "Upper_End"
Horseshoe_upper.ViewObject.Visibility = False
# the U-part of the horse shoe
# credits: https://forum.freecad.org/viewtopic.php?p=663051#p663051
vpairs = [[Vector (340.0, 200.0, 0.0), Vector (200.0, 200.0, 0.0)],
[Vector (200.0, 200.0, 0.0), Vector (200.0, 100.0, 0.0)],
[Vector (200.0, 100.0, 0.0), Vector (325.0, 100.0, 0.0)],
[Vector (325.0, 100.0, 0.0), Vector (325.0, -100.0, 0.0)],
[Vector (325.0, -100.0, 0.0), Vector (200.0, -100.0, 0.0)],
[Vector (200.0, -100.0, 0.0), Vector (200.0, -200.0, 0.0)],
[Vector (200.0, -200.0, 0.0), Vector (340.0, -200.0, 0.0)],
[Vector (340.0, 200.0, 0.0), Vector (340.0, -200.0, 0.0)]]
typeId = ['Part::GeomLine', 'Part::GeomLine', 'Part::GeomLine', 'Part::GeomBSplineCurve',
'Part::GeomLine', 'Part::GeomLine', 'Part::GeomLine', 'Part::GeomBSplineCurve']
e3Poles = [Vector (325.0, 100.0, 0.0), Vector (400.0, 100.0, 0.0),
Vector (400.0, 0.0, 0.0), Vector (400.0, -100.0, 0.0),
Vector (325.0, -100.0, 0.0)]
e3Knots = [0.0, 0.5, 1.0]
e3Mults = [4, 1, 4]
e3Degree = 3
e7Poles = [Vector (340.0, 200.0, 0.0), Vector (500.0, 200.0, 0.0),
Vector (500.0, 0.0, 0.0), Vector (500.0, -200.0, 0.0),
Vector (340.0, -200.0, 0.0)]
e7Knots = [0.0, 0.5, 1.0]
e7Mults = [4, 1, 4]
e7Degree = 3
c3 = Part.BSplineCurve()
c3.buildFromPolesMultsKnots(e3Poles, e3Mults, e3Knots, False, e3Degree)
c7 = Part.BSplineCurve()
c7.buildFromPolesMultsKnots(e7Poles, e7Mults, e7Knots, False, e7Degree)
edges = [c3.toShape(), c7.toShape()]
for i in range(len(typeId)):
if typeId[i] == 'Part::GeomLine':
edges.append(Part.makeLine(*vpairs[i]))
sedges = Part.__sortEdges__(edges)
Horseshoe_U = doc.addObject("Part::Feature", "Horseshoe_U")
Horseshoe_U.Shape = Part.Face(Part.Wire(sedges))
# a circle defining later the air volume
Air_Circle = doc.addObject("Part::Feature", "Air_Circle")
Air_Circle.Shape = Part.Face(Part.Wire(Part.makeCircle(1500.0)))
# a link of the Horseshoe_lower
Horseshoe_lowerLink = doc.addObject("App::Link", "Link_Lower_End")
Horseshoe_lowerLink.LinkTransform = True
Horseshoe_lowerLink.LinkedObject = Horseshoe_lower
Horseshoe_lowerLink.ViewObject.Visibility = False
# a link of the Horseshoe_upper
Horseshoe_upperLink = doc.addObject("App::Link", "Link_Upper_End")
Horseshoe_upperLink.LinkTransform = True
Horseshoe_upperLink.LinkedObject = Horseshoe_upper
Horseshoe_upperLink.ViewObject.Visibility = False
# a link of the Horseshoe_U
Horseshoe_ULink = doc.addObject("App::Link", "Link_Horseshoe_U")
Horseshoe_ULink.LinkTransform = True
Horseshoe_ULink.LinkedObject = Horseshoe_U
Horseshoe_ULink.ViewObject.Visibility = False
# fusion of all links
Fusion = doc.addObject("Part::MultiFuse", "Fusion")
Fusion.Shapes = [Horseshoe_lowerLink, Horseshoe_upperLink, Horseshoe_ULink]
Fusion.ViewObject.Visibility = False
# cut all objects from Air wire to get volume of fluid
Cut = doc.addObject("Part::Cut", "Cut_Air")
Cut.Base = Air_Circle
Cut.Tool = Fusion
Cut.ViewObject.Visibility = False
# BooleanFregments object to combine cut with rod
BooleanFragments = SplitFeatures.makeBooleanFragments(name="BooleanFragments")
BooleanFragments.Objects = [Horseshoe_lower, Horseshoe_upper, Horseshoe_U, Cut]
# set view
doc.recompute()
if FreeCAD.GuiUp:
BooleanFragments.ViewObject.Document.activeView().viewTop()
BooleanFragments.ViewObject.Document.activeView().fitAll()
# analysis
analysis = ObjectsFem.makeAnalysis(doc, "Analysis")
if FreeCAD.GuiUp:
import FemGui
FemGui.setActiveAnalysis(analysis)
# solver
if solvertype == "elmer":
solver_obj = ObjectsFem.makeSolverElmer(doc, "SolverElmer")
solver_obj.CoordinateSystem = "Cartesian 2D"
equation_magnetodynamic2D = ObjectsFem.makeEquationMagnetodynamic2D(doc, solver_obj)
equation_magnetodynamic2D.CalculateMagneticFieldStrength = True
else:
FreeCAD.Console.PrintWarning(
"Not known or not supported solver type: {}. "
"No solver object was created.\n".format(solvertype)
)
return doc
analysis.addObject(solver_obj)
# materials
# air around the horse shoe
material_obj = ObjectsFem.makeMaterialFluid(doc, "Air")
mat = material_obj.Material
mat["Name"] = "Air"
mat["Density"] = "1.204 kg/m^3"
mat["ThermalConductivity"] = "0.02587 W/m/K"
mat["ThermalExpansionCoefficient"] = "3.43e-3 1/K"
mat["SpecificHeat"] = "1.01 kJ/kg/K"
mat["ElectricalConductivity"] = "1e-12 S/m"
mat["RelativePermeability"] = "1.0"
mat["RelativePermittivity"] = "1.00059"
material_obj.Material = mat
material_obj.References = [(BooleanFragments, "Face4")]
analysis.addObject(material_obj)
# iron of the horse shoe
material_obj = ObjectsFem.makeMaterialSolid(doc, "Iron")
mat = material_obj.Material
mat["Name"] = "Iron Generic"
mat["ElectricalConductivity"] = "10.3 MS/m"
mat["RelativePermeability"] = "5000.0"
material_obj.Material = mat
material_obj.References = [
(BooleanFragments, "Face1"),
(BooleanFragments, "Face2"),
(BooleanFragments, "Face3")]
analysis.addObject(material_obj)
# magnetization lower
Magnetization_lower = ObjectsFem.makeConstraintMagnetization(doc, "Magnetization_Lower_End")
Magnetization_lower.References = [(BooleanFragments, "Face1")]
Magnetization_lower.Magnetization_re_1 = "-7500.0 A/m"
Magnetization_lower.Magnetization_re_1_Disabled = False
analysis.addObject(Magnetization_lower)
# magnetization upper
Magnetization_upper = ObjectsFem.makeConstraintMagnetization(doc, "Magnetization_Upper_End")
Magnetization_upper.References = [(BooleanFragments, "Face2")]
Magnetization_upper.Magnetization_re_1 = "7500.0 A/m"
Magnetization_upper.Magnetization_re_1_Disabled = False
analysis.addObject(Magnetization_upper)
# mesh
femmesh_obj = analysis.addObject(ObjectsFem.makeMeshGmsh(doc, get_meshname()))[0]
femmesh_obj.Part = BooleanFragments
femmesh_obj.CharacteristicLengthMax = "100.0 mm"
femmesh_obj.ViewObject.Visibility = False
# mesh_region
mesh_region = ObjectsFem.makeMeshRegion(doc, femmesh_obj, name="MeshRegion")
mesh_region.CharacteristicLength = "6.5 mm"
mesh_region.References = [
(BooleanFragments, "Face1"),
(BooleanFragments, "Face2"),
(BooleanFragments, "Face3")]
mesh_region.ViewObject.Visibility = False
# generate the mesh
from femmesh import gmshtools
gmsh_mesh = gmshtools.GmshTools(femmesh_obj, analysis)
try:
error = gmsh_mesh.create_mesh()
except Exception:
error = sys.exc_info()[1]
FreeCAD.Console.PrintError(
"Unexpected error when creating mesh: {}\n"
.format(error)
)
doc.recompute()
return doc

2
src/Mod/Fem/femexamples/manager.py
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@@ -74,6 +74,7 @@ def run_all():
run_example("equation_flux_elmer", run_solver=True)
run_example("equation_magnetodynamics_elmer", run_solver=True)
run_example("equation_magnetodynamics_2D_elmer.py", run_solver=True)
run_example("equation_magnetostatics_2D_elmer.py", run_solver=True)
run_example("frequency_beamsimple", run_solver=True)
run_example("material_multiple_bendingbeam_fiveboxes", run_solver=True)
run_example("material_multiple_bendingbeam_fivefaces", run_solver=True)
@@ -110,6 +111,7 @@ def setup_all():
run_example("equation_flux_elmer")
run_example("equation_magnetodynamics_elmer")
run_example("equation_magnetodynamics_2D_elmer.py")
run_example("equation_magnetostatics_2D_elmer.py")
run_example("frequency_beamsimple")
run_example("material_multiple_bendingbeam_fiveboxes")
run_example("material_multiple_bendingbeam_fivefaces")