.Modelica.Media.IdealGases.Common.SingleGasNasa

Information

This model calculates medium properties for an ideal gas of a single substance, or for an ideal gas consisting of several substances where the mass fractions are fixed. Independent variables are temperature T and pressure p. Only density is a function of T and p. All other quantities are solely a function of T. The properties are valid in the range:

200 K ≤ T ≤ 6000 K

The following quantities are always computed:

For the other variables, see the functions in Modelica.Media.IdealGases.Common.SingleGasNasa. Note, dynamic viscosity and thermal conductivity are only provided for gases that use a data record from Modelica.Media.IdealGases.FluidData. Currently these are the following gases:

Ar
C2H2_vinylidene
C2H4
C2H5OH
C2H6
C3H6_propylene
C3H7OH
C3H8
C4H8_1_butene
C4H9OH
C4H10_n_butane
C5H10_1_pentene
C5H12_n_pentane
C6H6
C6H12_1_hexene
C6H14_n_heptane
C7H14_1_heptene
C8H10_ethylbenz
CH3OH
CH4
CL2
CO
CO2
F2
H2
H2O
He
N2
N2O
NH3
NO
O2
SO2
SO3

Sources for model and literature:
Original Data: Computer program for calculation of complex chemical equilibrium compositions and applications. Part 1: Analysis Document ID: 19950013764 N (95N20180) File Series: NASA Technical Reports Report Number: NASA-RP-1311 E-8017 NAS 1.61:1311 Authors: Gordon, Sanford (NASA Lewis Research Center) Mcbride, Bonnie J. (NASA Lewis Research Center) Published: Oct 01, 1994.

Known limits of validity:
The data is valid for temperatures between 200K and 6000K. A few of the data sets for monatomic gases have a discontinuous 1st derivative at 1000K, but this never caused problems so far.

This model has been copied from the ThermoFluid library and adapted to the Modelica.Media package.

Contents

Name	Description
ThermodynamicState	Thermodynamic state variables for ideal gases
BaseProperties	Base properties of ideal gas medium
setState_pTX	Return thermodynamic state as function of p, T and composition X
setState_phX	Return thermodynamic state as function of p, h and composition X
setState_psX	Return thermodynamic state as function of p, s and composition X
setState_dTX	Return thermodynamic state as function of d, T and composition X
setSmoothState	Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b
pressure	Return pressure of ideal gas
temperature	Return temperature of ideal gas
density	Return density of ideal gas
specificEnthalpy	Return specific enthalpy
specificInternalEnergy	Return specific internal energy
specificEntropy	Return specific entropy
specificGibbsEnergy	Return specific Gibbs energy
specificHelmholtzEnergy	Return specific Helmholtz energy
specificHeatCapacityCp	Return specific heat capacity at constant pressure
specificHeatCapacityCv	Compute specific heat capacity at constant volume from temperature and gas data
isentropicExponent	Return isentropic exponent
velocityOfSound	Return velocity of sound
isentropicEnthalpyApproximation	Approximate method of calculating h_is from upstream properties and downstream pressure
isentropicEnthalpy	Return isentropic enthalpy
isobaricExpansionCoefficient	Returns overall the isobaric expansion coefficient beta
isothermalCompressibility	Returns overall the isothermal compressibility factor
density_derp_T	Returns the partial derivative of density with respect to pressure at constant temperature
density_derT_p	Returns the partial derivative of density with respect to temperature at constant pressure
density_derX	Returns the partial derivative of density with respect to mass fractions at constant pressure and temperature
dynamicViscosity	Dynamic viscosity
thermalConductivity	Thermal conductivity of gas
molarMass	Return the molar mass of the medium
T_h	Compute temperature from specific enthalpy
T_ps	Compute temperature from pressure and specific entropy
dynamicViscosityLowPressure	Dynamic viscosity of low pressure gases
thermalConductivityEstimate	Thermal conductivity of polyatomic gases(Eucken and Modified Eucken correlation)