Package Constants (22)

e	Value: Modelica.Math.exp(1.0) Type: Real
pi	Value: 2 * Modelica.Math.asin(1.0) Type: Real
D2R	Value: pi / 180 Type: Real Description: Degree to Radian
R2D	Value: 180 / pi Type: Real Description: Radian to Degree
gamma	Value: 0.57721566490153286061 Type: Real Description: See http://en.wikipedia.org/wiki/Euler_constant
eps	Value: ModelicaServices.Machine.eps Type: Real Description: Biggest number such that 1.0 + eps = 1.0
small	Value: ModelicaServices.Machine.small Type: Real Description: Smallest number such that small and -small are representable on the machine
inf	Value: ModelicaServices.Machine.inf Type: Real Description: Biggest Real number such that inf and -inf are representable on the machine
Integer_inf	Value: ModelicaServices.Machine.Integer_inf Type: Integer Description: Biggest Integer number such that Integer_inf and -Integer_inf are representable on the machine
c	Value: 299792458 Type: Velocity (m/s) Description: Speed of light in vacuum
g_n	Value: 9.80665 Type: Acceleration (m/s²) Description: Standard acceleration of gravity on earth
G	Value: 6.67430e-11 Type: Real (m³/(kg·s²)) Description: Newtonian constant of gravitation
q	Value: 1.602176634e-19 Type: ElectricCharge (C) Description: Elementary charge
F	Value: q * N_A Type: FaradayConstant (C/mol) Description: Faraday constant, C/mol
h	Value: 6.62607015e-34 Type: Real (J·s) Description: Planck constant
k	Value: 1.380649e-23 Type: Real (J/K) Description: Boltzmann constant
R	Value: k * N_A Type: Real (J/(mol·K)) Description: Molar gas constant
sigma	Value: 2 * pi ^ 5 * k ^ 4 / (15 * h ^ 3 * c ^ 2) Type: Real (W/(m²·K⁴)) Description: Stefan-Boltzmann constant
N_A	Value: 6.02214076e23 Type: Real (¹/mol) Description: Avogadro constant
mu_0	Value: 4 * pi * 1.00000000055e-7 Type: Real (N/A²) Description: Magnetic constant
epsilon_0	Value: 1 / (mu_0 * c * c) Type: Real (F/m) Description: Electric constant
T_zero	Value: -273.15 Type: Temperature_degC (°C) Description: Absolute zero temperature

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

This package provides often needed constants from mathematics, machine dependent constants and constants from nature. The latter constants (name, value, description) are from the following source (based on the second source):

Michael Stock, Richard Davis, Estefanía de Mirandés and Martin J T Milton:: The revision of the SI-the result of three decades of progress in metrology in Metrologia, Volume 56, Number 2. https://iopscience.iop.org/article/10.1088/1681-7575/ab0013/pdf, 2019.

D B Newell, F Cabiati, J Fischer, K Fujii, S G Karshenboim, H S Margolis , E de Mirandés, P J Mohr, F Nez, K Pachucki, T J Quinn, B N Taylor, M Wang, B M Wood and Z Zhang:: The CODATA 2017 values of h, e, k, and NA for the revision of the SI in Metrologia, Volume 55, Number 1. https://iopscience.iop.org/article/10.1088/1681-7575/aa950a/pdf, 2017.

BIPM is Bureau International des Poids et Mesures (they publish the SI-standard).

CODATA is the Committee on Data for Science and Technology.

Main Author:: Martin Otter
Deutsches Zentrum für Luft und Raumfahrt e. V. (DLR)
Oberpfaffenhofen
Postfach 1116
D-82230 Weßling
email: Martin.Otter@dlr.de