69 lines
2.8 KiB
Python
69 lines
2.8 KiB
Python
# ***************************************************************************
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# * Copyright (c) 2020 Bernd Hahnebach <bernd@bimstatik.org> *
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# * *
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# * This file is part of the FreeCAD CAx development system. *
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# * *
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# * This program is free software; you can redistribute it and/or modify *
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# * it under the terms of the GNU Lesser General Public License (LGPL) *
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# * as published by the Free Software Foundation; either version 2 of *
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# * the License, or (at your option) any later version. *
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# * for detail see the LICENCE text file. *
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# * *
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# * This program is distributed in the hope that it will be useful, *
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# * but WITHOUT ANY WARRANTY; without even the implied warranty of *
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# * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
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# * GNU Library General Public License for more details. *
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# * *
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# * You should have received a copy of the GNU Library General Public *
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# * License along with this program; if not, write to the Free Software *
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# * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 *
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# * USA *
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# * *
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# ***************************************************************************
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""" Collection of natural constants for the Fem module.
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This module contains natural constants for the Fem module.
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All constants are in SI units.
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"""
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__title__ = "FEM collection of natural constants"
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__author__ = "Bernd Hahnebach"
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__url__ = "https://www.freecad.org"
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def gravity():
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# https://en.wikipedia.org/wiki/Gravitational_acceleration
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return "9.80665 m/s^2"
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def stefan_boltzmann():
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# https://en.wikipedia.org/wiki/Stefan-Boltzmann_constant
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return "5.67037e-8 W/(m^2*K^4)"
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def vacuum_permeability():
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# https://en.wikipedia.org/wiki/Vacuum_permeability
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return "1.256637e-6 N/A^2"
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def vacuum_permittivity():
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# https://forum.freecad.org/viewtopic.php?f=18&p=400959#p400959
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# https://en.wikipedia.org/wiki/Permittivity#Vacuum_permittivity
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return "8.85419e-12 F/m"
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def boltzmann_constant():
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# https://en.wikipedia.org/wiki/Boltzmann_constant
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return "1.38065e-23 J/K"
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"""
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from FreeCAD import Units
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from femtools import constants
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Units.Quantity(constants.gravity()).getValueAs("mm/s^2")
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"""
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# TODO: a unit test to be sure these values are returned!
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