freecad-cam/Mod/Fem/femsolver/calculix/write_femelement_material.py
2026-02-01 01:59:24 +01:00

125 lines
6.1 KiB
Python

# ***************************************************************************
# * Copyright (c) 2021 Bernd Hahnebach <bernd@bimstatik.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 *
# * *
# ***************************************************************************
__title__ = "FreeCAD FEM calculix write inpfile materials"
__author__ = "Bernd Hahnebach"
__url__ = "https://www.freecad.org"
import FreeCAD
def write_femelement_material(f, ccxwriter):
# floats read from ccx should use {:.13G}, see comment in writer module
# see unit comment in writer module
def is_density_needed():
if ccxwriter.analysis_type == "frequency":
return True
if (
ccxwriter.analysis_type == "thermomech"
and not ccxwriter.solver_obj.ThermoMechSteadyState
):
return True
if ccxwriter.member.cons_centrif:
return True
if ccxwriter.member.cons_selfweight:
return True
return False
f.write("\n** Physical constants for SI(mm) unit system with Kelvins\n")
f.write("*PHYSICAL CONSTANTS, ABSOLUTE ZERO=0, STEFAN BOLTZMANN=5.670374419e-11\n")
f.write("\n{}\n".format(59 * "*"))
f.write("** Materials\n")
f.write("** see information about units at file end\n")
for femobj in ccxwriter.member.mats_linear:
# femobj --> dict, FreeCAD document object is femobj["Object"]
mat_obj = femobj["Object"]
mat_info_name = mat_obj.Material["Name"]
mat_name = mat_obj.Name
mat_label = mat_obj.Label
# get material properties of solid material, Currently in SI units: M/kg/s/Kelvin
if mat_obj.Category == "Solid":
YM = FreeCAD.Units.Quantity(mat_obj.Material["YoungsModulus"])
YM_in_MPa = YM.getValueAs("MPa").Value
PR = float(mat_obj.Material["PoissonRatio"])
if is_density_needed() is True:
density = FreeCAD.Units.Quantity(mat_obj.Material["Density"])
density_in_tonne_per_mm3 = density.getValueAs("t/mm^3").Value
if ccxwriter.analysis_type == "thermomech":
TC = FreeCAD.Units.Quantity(mat_obj.Material["ThermalConductivity"])
# SvdW: Add factor to force units to results base units
# of t/mm/s/K - W/m/K results in no factor needed
TC_in_WmK = TC.getValueAs("W/m/K").Value
SH = FreeCAD.Units.Quantity(mat_obj.Material["SpecificHeat"])
# SvdW: Add factor to force units to results base units of t/mm/s/K
# FIXME: why not get it directly in the units needed ?
SH_in_JkgK = SH.getValueAs("J/kg/K").Value * 1e06
if mat_obj.Category == "Solid":
TEC = FreeCAD.Units.Quantity(mat_obj.Material["ThermalExpansionCoefficient"])
TEC_in_mmK = TEC.getValueAs("mm/mm/K").Value
elif mat_obj.Category == "Fluid":
KV = FreeCAD.Units.Quantity(mat_obj.Material["KinematicViscosity"])
KV_in_mm2s = KV.getValueAs("mm^2/s").Value
DV_in_tmms = KV_in_mm2s * density_in_tonne_per_mm3
# write material properties
f.write(f"** FreeCAD material name: {mat_info_name}\n")
f.write(f"** {mat_label}\n")
f.write(f"*MATERIAL, NAME={mat_name}\n")
if mat_obj.Category == "Solid":
f.write("*ELASTIC\n")
f.write(f"{YM_in_MPa:.13G},{PR:.13G}\n")
if is_density_needed() is True:
f.write("*DENSITY\n")
f.write(f"{density_in_tonne_per_mm3:.13G}\n")
if ccxwriter.analysis_type == "thermomech":
if mat_obj.Category == "Solid":
f.write("*CONDUCTIVITY\n")
f.write(f"{TC_in_WmK:.13G}\n")
f.write("*EXPANSION\n")
f.write(f"{TEC_in_mmK:.13G}\n")
f.write("*SPECIFIC HEAT\n")
f.write(f"{SH_in_JkgK:.13G}\n")
elif mat_obj.Category == "Fluid":
f.write("*FLUID CONSTANTS\n")
f.write(f"{SH_in_JkgK:.13G},{DV_in_tmms:.13G}\n")
# nonlinear material properties
if ccxwriter.solver_obj.MaterialNonlinearity == "nonlinear":
for nlfemobj in ccxwriter.member.mats_nonlinear:
# femobj --> dict, FreeCAD document object is nlfemobj["Object"]
nl_mat_obj = nlfemobj["Object"]
if nl_mat_obj.LinearBaseMaterial == mat_obj:
if nl_mat_obj.MaterialModelNonlinearity == "isotropic hardening":
f.write("*PLASTIC\n")
else:
f.write("*PLASTIC, HARDENING=KINEMATIC\n")
for yield_point in nl_mat_obj.YieldPoints:
f.write(f"{yield_point}\n")
f.write("\n")