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[FEM] proper Elmer input file write solution

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- assure that independent on the used unit scheme, SI units are written to the Elmer input file
- reverts commits https://github.com/FreeCAD/FreeCAD/commit/9db165b24b and https://github.com/FreeCAD/FreeCAD/commit/c707d192e
This commit is contained in:
Uwe
2022-03-19 17:48:11 +01:00
parent dd28df0a69
commit 842b781a41
1 changed files with 32 additions and 58 deletions
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90
src/Mod/Fem/femsolver/elmer/writer.py
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@@ -110,7 +110,7 @@ class Writer(object):
# instead of hard coding them here for a second once
self.unit_schema = Units.Scheme.SI1
self.unit_system = { # standard FreeCAD Base units = unit schema 0
"L": "mm",
"L": "m",
"M": "kg",
"T": "s",
"I": "A",
@@ -123,7 +123,7 @@ class Writer(object):
if self.unit_schema == Units.Scheme.SI1:
Console.PrintMessage(
"The FreeCAD standard unit schema mm/kg/s is used. "
"Elmer sif-file writing is done in Standard FreeCAD units.\n"
"Elmer sif-file writing is however done in SI units.\n"
)
elif self.unit_schema == Units.Scheme.SI2:
Console.PrintMessage(
@@ -143,10 +143,10 @@ class Writer(object):
# see also unit comment in calculix writer
Console.PrintMessage(
"The FEM unit schema mm/N/s is used. "
"Elmer sif-file writing is done in FEM-units.\n"
"Elmer sif-file writing is however done in SI units.\n"
)
self.unit_system = {
"L": "mm",
"L": "m",
"M": "t",
"T": "s",
"I": "A",
@@ -269,8 +269,7 @@ class Writer(object):
permittivity_objs = self._getMember("Fem::ConstantVacuumPermittivity")
if len(permittivity_objs) == 1:
Console.PrintLog("Constand permittivity overwriting.\n")
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e9
self._setConstant("PermittivityOfVacuum", permittivity_objs[0].VacuumPermittivity * 1e9)
self._setConstant("PermittivityOfVacuum", permittivity_objs[0].VacuumPermittivity)
elif len(permittivity_objs) > 1:
Console.PrintError(
"More than one permittivity constant overwriting objects ({} objs). "
@@ -341,8 +340,7 @@ class Writer(object):
temp = self._getFromUi(obj.Temperature, "K", "O")
self._boundary(name, "Temperature", temp)
elif obj.ConstraintType == "CFlux":
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-6
flux = self._getFromUi(obj.CFlux * 1e-6, "kg*mm^2*s^-3", "M*L^2*T^-3")
flux = self._getFromUi(obj.CFlux, "kg*mm^2*s^-3", "M*L^2*T^-3")
self._boundary(name, "Temperature Load", flux)
self._handled(obj)
for obj in self._getMember("Fem::ConstraintHeatflux"):
@@ -371,8 +369,7 @@ class Writer(object):
obj = self._getSingleMember("Fem::ConstraintBodyHeatSource")
if obj is not None:
for name in bodies:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-6
heatSource = self._getFromUi(obj.HeatSource * 1e-6, "W/kg", "L^2*T^-3")
heatSource = self._getFromUi(obj.HeatSource, "W/kg", "L^2*T^-3")
# according Elmer forum W/kg is correct
# http://www.elmerfem.org/forum/viewtopic.php?f=7&t=1765
# 1 watt = kg * m2 / s3 ... W/kg = m2 / s3
@@ -395,14 +392,12 @@ class Writer(object):
self._material(
name, "Density",
self._getDensity(m))
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
HeatConductivity = self._convert(m["ThermalConductivity"], "M*L/(T^3*O)")
HeatConductivity *= 1e-3
self._material(name, "Heat Conductivity", HeatConductivity)
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-6
HeatCapacity = self._convert(m["SpecificHeat"], "L^2/(T^2*O)")
HeatCapacity *= 1e-6
self._material( name, "Heat Capacity", HeatCapacity)
self._material(
name, "Heat Conductivity",
self._convert(m["ThermalConductivity"], "M*L/(T^3*O)"))
self._material(
name, "Heat Capacity",
self._convert(m["SpecificHeat"], "L^2/(T^2*O)"))
def _handleElectrostatic(self):
activeIn = []
@@ -441,9 +436,11 @@ class Writer(object):
return s
def _handleElectrostaticConstants(self):
permittivityRaw = self._getConstant("PermittivityOfVacuum", "T^4*I^2/(L^3*M)")
permittivityRaw *= 1e9
self._constant("Permittivity Of Vacuum", permittivityRaw)
self._constant(
"Permittivity Of Vacuum",
self._getConstant("PermittivityOfVacuum", "T^4*I^2/(L^3*M)")
)
# https://forum.freecadweb.org/viewtopic.php?f=18&p=400959#p400959
def _handleElectrostaticMaterial(self, bodies):
for obj in self._getMember("App::MaterialObject"):
@@ -466,8 +463,7 @@ class Writer(object):
# https://forum.freecadweb.org/viewtopic.php?f=18&t=41488&start=10#p369454 ff
if obj.PotentialEnabled:
if hasattr(obj, "Potential"):
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-6
potential = self._getFromUi(obj.Potential * 1e-6, "V", "M*L^2/(T^3 * I)")
potential = self._getFromUi(obj.Potential, "V", "M*L^2/(T^3 * I)")
self._boundary(name, "Potential", potential)
if obj.PotentialConstant:
self._boundary(name, "Potential Constant", True)
@@ -563,8 +559,7 @@ class Writer(object):
for obj in self._getMember("Fem::ConstraintPressure"):
if obj.References:
for name in obj.References[0][1]:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e3
pressure = self._getFromUi(obj.Pressure * 1e3, "MPa", "M/(L*T^2)")
pressure = self._getFromUi(obj.Pressure, "MPa", "M/(L*T^2)")
if not obj.Reversed:
pressure *= -1
self._boundary(name, "Normal Force", pressure)
@@ -579,8 +574,7 @@ class Writer(object):
for obj in self._getMember("Fem::ConstraintForce"):
if obj.References:
for name in obj.References[0][1]:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
force = self._getFromUi(obj.Force * 1e-3, "N", "M*L*T^-2")
force = self._getFromUi(obj.Force, "N", "M*L*T^-2")
self._boundary(name, "Force 1", obj.DirectionVector.x * force)
self._boundary(name, "Force 2", obj.DirectionVector.y * force)
self._boundary(name, "Force 3", obj.DirectionVector.z * force)
@@ -618,17 +612,13 @@ class Writer(object):
gravity = self._getConstant("Gravity", "L/T^2")
m = self._getBodyMaterial(name).Material
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e9
densityQuantityRaw = Units.Quantity(m["Density"])
densityQuantity = densityQuantityRaw * 1e9
densityQuantity = Units.Quantity(m["Density"])
dimension = "M/L^3"
if name.startswith("Edge"):
# not tested, bernd
# TODO: test
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e6
densityQuantity.Unit = Units.Unit(-2, 1)
dimension = "M/L^2"
densityQuantity = densityQuantityRaw * 1e6
density = self._convert(densityQuantity, dimension)
force1 = gravity * obj.Gravity_x * density
@@ -692,17 +682,13 @@ class Writer(object):
)
def _getDensity(self, m):
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e9
density = self._convert(m["Density"], "M/L^3")
density *= 1e9
if self._getMeshDimension() == 2:
density *= 1e3
return density
def _getYoungsModulus(self, m):
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e3
youngsModulus = self._convert(m["YoungsModulus"], "M/(L*T^2)")
youngsModulus *= 1e3;
if self._getMeshDimension() == 2:
youngsModulus *= 1e3
return youngsModulus
@@ -739,9 +725,7 @@ class Writer(object):
return s
def _handleFlowConstants(self):
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
gravity = self._getConstant("Gravity", "L/T^2")
gravity *= 1e-3
self._constant("Gravity", (0.0, -1.0, 0.0, gravity))
def _handleFlowMaterial(self, bodies):
@@ -763,15 +747,13 @@ class Writer(object):
self._getDensity(m)
)
if "ThermalConductivity" in m:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
HeatConductivity = self._convert(m["ThermalConductivity"], "M*L/(T^3*O)")
HeatConductivity *= 1e-3
self._material(name, "Heat Conductivity", HeatConductivity)
self._material(
name, "Heat Conductivity",
self._convert(m["ThermalConductivity"], "M*L/(T^3*O)")
)
if "KinematicViscosity" in m:
density = self._getDensity(m)
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-6
kViscosity = self._convert(m["KinematicViscosity"], "L^2/T")
kViscosity *= 1e-6
self._material(
name, "Viscosity", kViscosity * density)
if "ThermalExpansionCoefficient" in m:
@@ -780,9 +762,7 @@ class Writer(object):
self._material(
name, "Heat expansion Coefficient", value)
if "ReferencePressure" in m:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
pressure = self._convert(m["ReferencePressure"], "M/(L*T^2)")
pressure *= 1e-3
self._material(name, "Reference Pressure", pressure)
if "SpecificHeatRatio" in m:
self._material(
@@ -799,16 +779,13 @@ class Writer(object):
if obj is not None:
for name in bodies:
if obj.VelocityXEnabled:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
velocity = self._getFromUi(obj.VelocityX * 1e-3, "m/s", "L/T")
velocity = self._getFromUi(obj.VelocityX, "m/s", "L/T")
self._initial(name, "Velocity 1", velocity)
if obj.VelocityYEnabled:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
velocity = self._getFromUi(obj.VelocityY * 1e-3, "m/s", "L/T")
velocity = self._getFromUi(obj.VelocityY, "m/s", "L/T")
self._initial(name, "Velocity 2", velocity)
if obj.VelocityZEnabled:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
velocity = self._getFromUi(obj.VelocityZ * 1e-3, "m/s", "L/T")
velocity = self._getFromUi(obj.VelocityZ, "m/s", "L/T")
self._initial(name, "Velocity 3", velocity)
self._handled(obj)
@@ -817,16 +794,13 @@ class Writer(object):
if obj.References:
for name in obj.References[0][1]:
if obj.VelocityXEnabled:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
velocity = self._getFromUi(obj.VelocityX * 1e-3, "m/s", "L/T")
velocity = self._getFromUi(obj.VelocityX, "m/s", "L/T")
self._boundary(name, "Velocity 1", velocity)
if obj.VelocityYEnabled:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
velocity = self._getFromUi(obj.VelocityY * 1e-3, "m/s", "L/T")
velocity = self._getFromUi(obj.VelocityY, "m/s", "L/T")
self._boundary(name, "Velocity 2", velocity)
if obj.VelocityZEnabled:
# Elmer uses SI units, FC uses mm for L, not m, thus the factor 1e-3
velocity = self._getFromUi(obj.VelocityZ * 1e-3, "m/s", "L/T")
velocity = self._getFromUi(obj.VelocityZ, "m/s", "L/T")
self._boundary(name, "Velocity 3", velocity)
if obj.NormalToBoundary:
self._boundary(name, "Normal-Tangential Velocity", True)