packageHelium
Helium
Extends from Interfaces.PartialHelmholtzMedium.
Information
These are the coefficients for Helium. The reference state is set to NBP (saturated liquid at 101325 Pa: h = 0, s = 0), the REFPROP default.The equation of state was fitted with the molar gas constant R = 8.314472 J/(mol K), whereas HelmholtzMedia uses the exact value Modelica.Constants.R = 8.31446261815324 J/(mol K) for all fluids. The relative difference of 1.1e-6 is far below the uncertainty of the equation of state; the check values in Tables 3 and 4 of NIST IR 8474 are reproduced within their stated digits (see Examples.Validation.EoSHelium).
The ancillary equations for saturation pressure and densities are those of REFPROP 10.
- Ortiz Vega, D.O., Hall, K.R., Holste, J.C., Harvey, A.H. and Lemmon, E.W.
- An Equation of State for the Thermodynamic Properties of Helium
NIST Internal Report 8474, National Institute of Standards and Technology, 2023.
DOI: 10.6028/NIST.IR.8474 - Arp, V.D., McCarty, R.D. and Friend, D.G.
- Thermophysical Properties of Helium-4 from 0.8 to 1500 K with Pressures to 2000 MPa (viscosity)
NIST Technical Note 1334 (revised), 1998.
URL: nbstechnicalnote1334.pdf - Hands, B.A. and Arp, V.D.
- A Correlation of Thermal Conductivity Data for Helium
Cryogenics, 21(12):697-703, 1981.
DOI: 10.1016/0011-2275(81)90211-3 - Mulero, A., Cachadiña, I. and Parra, M.I.
- Recommended Correlations for the Surface Tension of Common Fluids
J. Phys. Chem. Ref. Data, 41:043105, 2012.
DOI: 10.1063/1.4768782 - McCarty, R.D. and Arp, V.D.
- A new wide range equation of state for helium (melting line)
Adv. Cryo. Eng. 35:1465-1475 (1990) - Lemmon, Eric W.; Huber, M. L. and McLinden, M. O.
- NIST Standard Reference Database 23: Reference Fluid Thermodynamic and Transport Properties - REFPROP. 9.0
National Institute of Standards and Technology, Standard Reference Data Program. Gaithersburg
URL: http://www.nist.gov/srd/nist23.cfm
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Media.Interfaces.Choices.IndependentVariables | ThermoStates (from PartialMedium) | Enumeration type for independent variables | |
| String | mediumName (from PartialMedium) | "unusablePartialMedium" | Name of the medium |
| String[:] | substanceNames (from PartialMedium) | {mediumName} | Names of the mixture substances. Set substanceNames={mediumName} if only one substance. |
| String[:] | extraPropertiesNames (from PartialMedium) | fill("", 0) | Names of the additional (extra) transported properties. Set extraPropertiesNames=fill("",0) if unused |
| Boolean | singleState (from PartialMedium) | = true, if u and d are not a function of pressure | |
| Boolean | reducedX (from PartialMedium) | true | = true, if medium contains the equation sum(X) = 1.0; set reducedX=true, if only one substance (see docu for details) |
| Boolean | fixedX (from PartialMedium) | false | = true, if medium contains the equation X = reference_X |
| AbsolutePressure | reference_p (from PartialMedium) | 101325 | Reference pressure of Medium: default 1 atmosphere |
| Temperature | reference_T (from PartialMedium) | 298.15 | Reference temperature of Medium: default 25 deg Celsius |
| MassFraction[nX] | reference_X (from PartialMedium) | fill(1/nX, nX) | Default mass fractions of medium |
| AbsolutePressure | p_default (from PartialMedium) | 101325 | Default value for pressure of medium (for initialization) |
| Temperature | T_default (from PartialMedium) | Modelica.Units.Conversions.from_degC(20) | Default value for temperature of medium (for initialization) |
| SpecificEnthalpy | h_default (from PartialMedium) | specificEnthalpy_pTX(p_default, T_default, X_default) | Default value for specific enthalpy of medium (for initialization) |
| MassFraction[nX] | X_default (from PartialMedium) | reference_X | Default value for mass fractions of medium (for initialization) |
| ExtraProperty[nC] | C_default (from PartialMedium) | fill(0, nC) | Default value for trace substances of medium (for initialization) |
| Integer | nS (from PartialMedium) | size(substanceNames, 1) | Number of substances |
| Integer | nX (from PartialMedium) | nS | Number of mass fractions |
| Integer | nXi (from PartialMedium) | if fixedX then 0 else if reducedX then nS - 1 else nS | Number of structurally independent mass fractions (see docu for details) |
| Integer | nC (from PartialMedium) | size(extraPropertiesNames, 1) | Number of extra (outside of standard mass-balance) transported properties |
| Real[nC] | C_nominal (from PartialMedium) | 1.0e-6*ones(nC) | Default for the nominal values for the extra properties |
| Boolean | smoothModel (from PartialTwoPhaseMedium) | false | = true, if the (derived) model should not generate state events |
| Boolean | onePhase (from PartialTwoPhaseMedium) | false | = true, if the (derived) model should never be called with two-phase inputs |
| FluidConstants | fluidConstants (from PartialTwoPhaseMedium) | Constant data for the fluid | |
| HelmholtzMedia.Interfaces.Types.EoSLimits | fluidLimits (from PartialHelmholtzMedium) | ||
| EoS.HelmholtzCoefficients | helmholtzCoefficients (from PartialHelmholtzMedium) | ||
| Transport.ThermalConductivityCoefficients | thermalConductivityCoefficients (from PartialHelmholtzMedium) | ||
| Transport.DynamicViscosityCoefficients | dynamicViscosityCoefficients (from PartialHelmholtzMedium) | ||
| Transport.SurfaceTensionCoefficients | surfaceTensionCoefficients (from PartialHelmholtzMedium) | ||
| Ancillary.AncillaryCoefficients | ancillaryCoefficients (from PartialHelmholtzMedium) | ||
| InputChoice | inputChoice (from PartialHelmholtzMedium) | InputChoice.ph | Default choice of input variables for property computations |
| FluidConstants | fluidConstantsHelium | Fluid Constants | |
| EoSLimits | fluidLimitsHelium | Helmholtz EoS Limits | |
| EoS.HelmholtzCoefficients | helmholtzCoefficientsHelium | Coefficients of the Helmholtz EoS | |
| Transport.ThermalConductivityCoefficients | thermalConductivityCoefficientsHelium | Coefficients for the thermal conductivity | |
| Transport.DynamicViscosityCoefficients | dynamicViscosityCoefficientsHelium | Coefficients for the dynamic viscosity | |
| Transport.SurfaceTensionCoefficients | surfaceTensionCoefficientsHelium | Coefficients for the surface tension | |
| Ancillary.AncillaryCoefficients | ancillaryCoefficientsHelium | Coefficients for the ancillary equations (PS5, DL1, DV3, ML1) |