Ideal gas medium model for dry air based on the package IdealGases with additional functions for dynamic viscosity and thermal conductivity in a limited temperature range.
Extends from Modelica.Icons.MaterialProperty
(Icon for property classes) and Modelica.Media.IdealGases.Common.SingleGasNasa
(Medium model of an ideal gas based on NASA source).
Name | Description |
---|---|
AbsolutePressure | Type for absolute pressure with medium specific attributes |
BaseProperties | Base properties of ideal gas medium |
Basic … | The most basic version of a record used in several degrees of detail |
beta | Alias for isobaricExpansionCoefficient for user convenience |
Choices … |   |
CumulativeExtraProperty | Type for conserved integral of unspecified, mass specific property |
Density | Type for density with medium specific attributes |
density | Return density of ideal gas |
density_derh_p | Return density derivative w.r.t. specific enthalpy at constant pressure |
density_derp_h | Return density derivative w.r.t. pressure at const specific enthalpy |
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 |
density_ph | Return density from p and h |
density_phX | Return density from p, h, and X or Xi |
density_ps | Return density from p and s |
density_psX | Return density from p, s, and X or Xi |
density_pT | Return density from p and T |
density_pTX | Return density from p, T, and X or Xi |
DerDensityByEnthalpy | Type for partial derivative of density with respect to enthalpy with medium specific attributes |
DerDensityByPressure | Type for partial derivative of density with respect to pressure with medium specific attributes |
DerDensityByTemperature | Type for partial derivative of density with respect to temperature with medium specific attributes |
DerEnthalpyByPressure | Type for partial derivative of enthalpy with respect to pressure with medium specific attributes |
DerTemperatureByPressure | Type for partial derivative of temperature with respect to pressure with medium specific attributes |
DipoleMoment | Type for dipole moment with medium specific attributes |
DynamicViscosity | Type for dynamic viscosity with medium specific attributes |
dynamicViscosity | Return dynamic viscosity of dry air (simple polynomial, moisture influence small, valid from 123.15 K to 1273.15 K, outside of this range linear extrapolation is used) |
dynamicViscosityLowPressure | Dynamic viscosity of low pressure gases |
EnthalpyFlowRate | Type for enthalpy flow rate with medium specific attributes |
ExtraProperty | Type for unspecified, mass-specific property transported by flow |
ExtraPropertyFlowRate | Type for flow rate of unspecified, mass-specific property |
FixedPhase | Phase of the fluid: 1 for 1-phase, 2 for two-phase, 0 for not known, e.g., interactive use |
FluidConstants |   |
FluidLimits | Validity limits for fluid model |
heatCapacity_cp | Alias for deprecated name |
heatCapacity_cv | Alias for deprecated name |
IdealGas … | The ideal gas version of a record used in several degrees of detail |
isentropicEnthalpy | Return isentropic enthalpy |
isentropicEnthalpyApproximation | Approximate method of calculating h_is from upstream properties and downstream pressure |
IsentropicExponent | Type for isentropic exponent with medium specific attributes |
isentropicExponent | Return isentropic exponent |
IsobaricExpansionCoefficient | Type for isobaric expansion coefficient with medium specific attributes |
isobaricExpansionCoefficient | Returns overall the isobaric expansion coefficient beta |
isothermalCompressibility | Returns overall the isothermal compressibility factor |
kappa | Alias of isothermalCompressibility for user convenience |
MassFlowRate | Type for mass flow rate with medium specific attributes |
MassFraction | Type for mass fraction with medium specific attributes |
MolarMass | Type for molar mass with medium specific attributes |
molarMass | Return the molar mass of the medium |
MolarVolume | Type for molar volume with medium specific attributes |
MoleFraction | Type for mole fraction with medium specific attributes |
PrandtlNumber | Type for Prandtl number with medium specific attributes |
prandtlNumber | Return the Prandtl number |
pressure | Return pressure of ideal gas |
pressure_dT | Return pressure from d and T |
SaturationProperties | Saturation properties of two phase medium |
setSmoothState | Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b |
setState_dT | Return thermodynamic state from d and T |
setState_dTX | Return thermodynamic state as function of d, T and composition X |
setState_ph | Return thermodynamic state from p and h |
setState_phX | Return thermodynamic state as function of p, h and composition X |
setState_ps | Return thermodynamic state from p and s |
setState_psX | Return thermodynamic state as function of p, s and composition X |
setState_pT | Return thermodynamic state from p and T |
setState_pTX | Return thermodynamic state as function of p, T and composition X |
SpecificEnergy | Type for specific energy with medium specific attributes |
SpecificEnthalpy | Type for specific enthalpy with medium specific attributes |
specificEnthalpy | Return specific enthalpy |
specificEnthalpy_dT | Return specific enthalpy from d and T |
specificEnthalpy_ps | Return specific enthalpy from p and s |
specificEnthalpy_psX | Return specific enthalpy from p, s, and X or Xi |
specificEnthalpy_pT | Return specific enthalpy from p and T |
specificEnthalpy_pTX | Return specific enthalpy from p, T, and X or Xi |
SpecificEntropy | Type for specific entropy with medium specific attributes |
specificEntropy | Return specific entropy |
specificEntropy_pTX | Return specific enthalpy from p, T, and X or Xi |
specificGibbsEnergy | Return specific Gibbs energy |
SpecificHeatCapacity | Type for specific heat capacity with medium specific attributes |
specificHeatCapacityCp | Return specific heat capacity at constant pressure |
specificHeatCapacityCv | Compute specific heat capacity at constant volume from temperature and gas data |
specificHelmholtzEnergy | Return specific Helmholtz energy |
SpecificInternalEnergy | Type for specific internal energy with medium specific attributes |
specificInternalEnergy | Return specific internal energy |
SurfaceTension | Type for surface tension with medium specific attributes |
T_h | Compute temperature from specific enthalpy |
T_ps | Compute temperature from pressure and specific entropy |
Temperature | Type for temperature with medium specific attributes |
temperature | Return temperature of ideal gas |
temperature_ph | Return temperature from p and h |
temperature_phX | Return temperature from p, h, and X or Xi |
temperature_ps | Return temperature from p and s |
temperature_psX | Return temperature from p,s, and X or Xi |
ThermalConductivity | Type for thermal conductivity with medium specific attributes |
thermalConductivity | Return thermal conductivity of dry air (simple polynomial, moisture influence small, valid from 123.15 K to 1273.15 K, outside of this range linear extrapolation is used) |
thermalConductivityEstimate | Thermal conductivity of polyatomic gases(Eucken and Modified Eucken correlation) |
ThermodynamicState | Thermodynamic state variables for ideal gases |
TwoPhase … | The two phase fluid version of a record used in several degrees of detail |
VelocityOfSound | Type for velocity of sound with medium specific attributes |
velocityOfSound | Return velocity of sound |
Type | Name | Value | Description |
---|---|---|---|
ExtraProperty | C_default[nC] | fill(0, nC) | Default value for trace substances of medium (for initialization) |
Real | C_nominal[nC] | 1e-6 * ones(nC) | Default for the nominal values for the extra properties |
DataRecord | data | IdealGases.Common.SingleGasesData.Air | Data record of ideal gas substance |
String | extraPropertiesNames[:] | fill("", 0) | Names of the additional (extra) transported properties. Set extraPropertiesNames=fill("",0) if unused |
final Boolean | fixedX | true | = true if medium contains the equation X = reference_X |
FluidConstants | fluidConstants[nS] | {IdealGases.Common.FluidData.N2} | Constant data for the fluid |
SpecificEnthalpy | h_default | specificEnthalpy_pTX(p_default, T_default, X_default) | Default value for specific enthalpy of medium (for initialization) |
String | mediumName | "Air" | Name of the medium |
final Integer | nC | size(extraPropertiesNames, 1) | Number of extra (outside of standard mass-balance) transported properties |
final Integer | nS | size(substanceNames, 1) | Number of substances |
Integer | nX | nS | Number of mass fractions |
Integer | nXi | if fixedX then 0 else if reducedX then nS - 1 else nS | Number of structurally independent mass fractions (see docu for details) |
AbsolutePressure | p_default | 101325 | Default value for pressure of medium (for initialization) |
final Boolean | reducedX | true | = true if medium contains the equation sum(X) = 1.0; set reducedX=true if only one substance (see docu for details) |
AbsolutePressure | reference_p | 101325 | Reference pressure of Medium: default 1 atmosphere |
Temperature | reference_T | 298.15 | Reference temperature of Medium: default 25 deg Celsius |
MassFraction | reference_X[nX] | fill(nX ^ (-1), nX) | Default mass fractions of medium |
Boolean | singleState | false | = true, if u and d are not a function of pressure |
String | substanceNames[:] | {data.name} | Names of the mixture substances. Set substanceNames={mediumName} if only one substance. |
Temperature | T_default | Modelica.SIunits.Conversions.from_degC(20) | Default value for temperature of medium (for initialization) |
IndependentVariables | ThermoStates | Modelica.Media.Interfaces.Choices.IndependentVariables.pT | Enumeration type for independent variables |
MassFraction | X_default[nX] | reference_X | Default value for mass fractions of medium (for initialization) |
Extends from Modelica.SIunits.AbsolutePressure
.
Name | Value |
---|---|
quantity | "Pressure" |
unit | "Pa" |
displayUnit | "bar" |
min | 0 |
max | 1e+8 |
start | 1000000 |
nominal | 1000000 |
Extends from Modelica.SIunits.Density
.
Name | Value |
---|---|
quantity | "Density" |
unit | "kg/m3" |
displayUnit | "g/cm3" |
min | 0 |
max | 100000 |
start | 10 |
nominal | 10 |
Extends from Modelica.SIunits.DynamicViscosity
.
Name | Value |
---|---|
quantity | "DynamicViscosity" |
unit | "Pa.s" |
min | 0 |
max | 1e+8 |
start | 0.001 |
nominal | 0.001 |
Extends from Modelica.SIunits.EnthalpyFlowRate
.
Name | Value |
---|---|
quantity | "EnthalpyFlowRate" |
unit | "W" |
min | -1e+8 |
max | 1e+8 |
start | 0. |
nominal | 1000 |
Extends from Real
.
Name | Value |
---|---|
quantity | "MassFraction" |
unit | "kg/kg" |
min | 0 |
max | 1 |
start | 0. |
nominal | 0.1 |
Extends from Real
.
Name | Value |
---|---|
quantity | "MoleFraction" |
unit | "mol/mol" |
min | 0 |
max | 1 |
start | 0. |
nominal | 0.1 |
Extends from Modelica.SIunits.MolarMass
.
Name | Value |
---|---|
quantity | "MolarMass" |
unit | "kg/mol" |
min | 0.001 |
max | 0.25 |
start | 0. |
nominal | 0.032 |
Extends from Modelica.SIunits.MolarVolume
.
Name | Value |
---|---|
quantity | "MolarVolume" |
unit | "m3/mol" |
min | 1e-6 |
max | 1000000 |
start | 0. |
nominal | 1 |
Extends from Modelica.SIunits.RatioOfSpecificHeatCapacities
.
Name | Value |
---|---|
quantity | "RatioOfSpecificHeatCapacities" |
unit | "1" |
min | 1 |
max | 500000 |
start | 1.2 |
nominal | 1.2 |
Extends from Modelica.SIunits.SpecificEnergy
.
Name | Value |
---|---|
quantity | "SpecificEnergy" |
unit | "J/kg" |
min | -1e+8 |
max | 1e+8 |
start | 0. |
nominal | 1000000 |
Extends from Modelica.Media.Air.DryAirNasa.SpecificEnergy
(Type for specific energy with medium specific attributes).
Name | Value |
---|---|
quantity | "SpecificEnergy" |
unit | "J/kg" |
min | -1e+8 |
max | 1e+8 |
start | 0. |
nominal | 1000000 |
Extends from Modelica.SIunits.SpecificEnthalpy
.
Name | Value |
---|---|
quantity | "SpecificEnergy" |
unit | "J/kg" |
min | -1e+10 |
max | 1e+10 |
start | if Functions.referenceChoice == ReferenceEnthalpy.ZeroAt0K then data.H0 else if Functions.referenceChoice == ReferenceEnthalpy.UserDefined then Functions.h_offset else 0 |
nominal | 100000 |
Extends from Modelica.SIunits.SpecificEntropy
.
Name | Value |
---|---|
quantity | "SpecificEntropy" |
unit | "J/(kg.K)" |
min | -1e+7 |
max | 1e+7 |
start | 0. |
nominal | 1000 |
Extends from Modelica.SIunits.SpecificHeatCapacity
.
Name | Value |
---|---|
quantity | "SpecificHeatCapacity" |
unit | "J/(kg.K)" |
min | 0 |
max | 1e+7 |
start | 1000 |
nominal | 1000 |
Extends from Modelica.SIunits.SurfaceTension
.
Name | Value |
---|---|
quantity | "SurfaceTension" |
unit | "N/m" |
min | -Modelica.Constants.inf |
max | Modelica.Constants.inf |
start | 0. |
Extends from Modelica.SIunits.Temperature
.
Name | Value |
---|---|
quantity | "ThermodynamicTemperature" |
unit | "K" |
displayUnit | "degC" |
min | 200 |
max | 6000 |
start | 500 |
nominal | 500 |
Extends from Modelica.SIunits.ThermalConductivity
.
Name | Value |
---|---|
quantity | "ThermalConductivity" |
unit | "W/(m.K)" |
min | 0 |
max | 500 |
start | 1 |
nominal | 1 |
Extends from Modelica.SIunits.PrandtlNumber
.
Name | Value |
---|---|
quantity | "PrandtlNumber" |
unit | "1" |
min | 0.001 |
max | 100000 |
start | 0. |
nominal | 1 |
Extends from Modelica.SIunits.Velocity
.
Name | Value |
---|---|
quantity | "Velocity" |
unit | "m/s" |
min | 0 |
max | 100000 |
start | 1000 |
nominal | 1000 |
Extends from Real
.
Name | Value |
---|---|
min | 0 |
max | Modelica.Constants.inf |
start | 1 |
Extends from Real
.
Name | Value |
---|---|
min | 0 |
max | Modelica.Constants.inf |
start | 1 |
Extends from Real
.
Name | Value |
---|---|
unit | "kg/s" |
min | -Modelica.Constants.inf |
max | Modelica.Constants.inf |
start | 0. |
Extends from Real
.
Name | Value |
---|---|
unit | "1/K" |
min | 0 |
max | 1e+8 |
start | 0. |
Extends from Real
.
Name | Value |
---|---|
quantity | "ElectricDipoleMoment" |
unit | "debye" |
min | 0 |
max | 2 |
start | 0. |
Extends from Modelica.SIunits.DerDensityByPressure
.
Name | Value |
---|---|
unit | "s2/m2" |
min | -Modelica.Constants.inf |
max | Modelica.Constants.inf |
start | 0. |
Extends from Modelica.SIunits.DerDensityByEnthalpy
.
Name | Value |
---|---|
unit | "kg.s2/m5" |
min | -Modelica.Constants.inf |
max | Modelica.Constants.inf |
start | 0. |
Extends from Modelica.SIunits.DerEnthalpyByPressure
.
Name | Value |
---|---|
unit | "J.m.s2/kg2" |
min | -Modelica.Constants.inf |
max | Modelica.Constants.inf |
start | 0. |
Extends from Modelica.SIunits.DerDensityByTemperature
.
Name | Value |
---|---|
unit | "kg/(m3.K)" |
min | -Modelica.Constants.inf |
max | Modelica.Constants.inf |
start | 0. |
Extends from Real
.
Name | Value |
---|---|
unit | "K/Pa" |
min | -Modelica.Constants.inf |
max | Modelica.Constants.inf |
start | 0. |
This icon is indicates a record.
Extends from Modelica.Icons.Record
(Icon for records).
Type | Name | Description |
---|---|---|
AbsolutePressure | psat | Saturation pressure |
Temperature | Tsat | Saturation temperature |
The minimum pressure mostly applies to the liquid state only. The minimum density is also arbitrary, but is reasonable for technical applications to limit iterations in non-linear systems. The limits in enthalpy and entropy are used as safeguards in inverse iterations.
Extends from Modelica.Icons.Record
(Icon for records).
Type | Name | Description |
---|---|---|
Temperature | TMIN | Minimum temperature |
Temperature | TMAX | Maximum temperature |
Density | DMIN | Minimum density |
Density | DMAX | Maximum density |
AbsolutePressure | PMIN | Minimum pressure |
AbsolutePressure | PMAX | Maximum pressure |
SpecificEnthalpy | HMIN | Minimum enthalpy |
SpecificEnthalpy | HMAX | Maximum enthalpy |
SpecificEntropy | SMIN | Minimum entropy |
SpecificEntropy | SMAX | Maximum entropy |
Extends from Integer
.
Name | Value |
---|---|
min | 0 |
max | 2 |
start | 0 |
This icon is indicates a record.
Extends from Modelica.Media.Interfaces.Types.IdealGas.FluidConstants
(Extended fluid constants).
Type | Name | Description |
---|---|---|
String | iupacName | Complete IUPAC name (or common name, if non-existent) |
String | casRegistryNumber | Chemical abstracts sequencing number (if it exists) |
String | chemicalFormula | Chemical formula, (brutto, nomenclature according to Hill |
String | structureFormula | Chemical structure formula |
MolarMass | molarMass | Molar mass |
Temperature | criticalTemperature | Critical temperature |
AbsolutePressure | criticalPressure | Critical pressure |
MolarVolume | criticalMolarVolume | Critical molar Volume |
Real | acentricFactor | Pitzer acentric factor |
Temperature | meltingPoint | Melting point at 101325 Pa |
Temperature | normalBoilingPoint | Normal boiling point (at 101325 Pa) |
DipoleMoment | dipoleMoment | Dipole moment of molecule in Debye (1 debye = 3.33564e10-30 C.m) |
Boolean | hasIdealGasHeatCapacity | True if ideal gas heat capacity is available |
Boolean | hasCriticalData | True if critical data are known |
Boolean | hasDipoleMoment | True if a dipole moment known |
Boolean | hasFundamentalEquation | True if a fundamental equation |
Boolean | hasLiquidHeatCapacity | True if liquid heat capacity is available |
Boolean | hasSolidHeatCapacity | True if solid heat capacity is available |
Boolean | hasAccurateViscosityData | True if accurate data for a viscosity function is available |
Boolean | hasAccurateConductivityData | True if accurate data for thermal conductivity is available |
Boolean | hasVapourPressureCurve | True if vapour pressure data, e.g., Antoine coefficients are known |
Boolean | hasAcentricFactor | True if Pitzer acentric factor is known |
SpecificEnthalpy | HCRIT0 | Critical specific enthalpy of the fundamental equation |
SpecificEntropy | SCRIT0 | Critical specific entropy of the fundamental equation |
SpecificEnthalpy | deltah | Difference between specific enthalpy model (h_m) and f.eq. (h_f) (h_m - h_f) |
SpecificEntropy | deltas | Difference between specific enthalpy model (s_m) and f.eq. (s_f) (s_m - s_f) |
This icon is indicates a record.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.ThermodynamicState
(Minimal variable set that is available as input argument to every medium function).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Absolute pressure of medium |
Temperature | T | Temperature of medium |
Model BaseProperties is a model within package PartialMedium and contains the declarations of the minimum number of variables that every medium model is supposed to support. A specific medium inherits from model BaseProperties and provides the equations for the basic properties.
The BaseProperties model contains the following 7+nXi variables (nXi is the number of independent mass fractions defined in package PartialMedium):
Variable | Unit | Description |
T | K | temperature |
p | Pa | absolute pressure |
d | kg/m3 | density |
h | J/kg | specific enthalpy |
u | J/kg | specific internal energy |
Xi[nXi] | kg/kg | independent mass fractions m_i/m |
R | J/kg.K | gas constant |
M | kg/mol | molar mass |
In order to implement an actual medium model, one can extend from this base model and add 5 equations that provide relations among these variables. Equations will also have to be added in order to set all the variables within the ThermodynamicState record state.
If standardOrderComponents=true, the full composition vector X[nX] is determined by the equations contained in this base class, depending on the independent mass fraction vector Xi[nXi].
Additional 2 + nXi equations will have to be provided when using the BaseProperties model, in order to fully specify the thermodynamic conditions. The input connector qualifier applied to p, h, and nXi indirectly declares the number of missing equations, permitting advanced equation balance checking by Modelica tools. Please note that this doesn't mean that the additional equations should be connection equations, nor that exactly those variables should be supplied, in order to complete the model. For further information, see the Modelica.Media User's guide, and Section 4.7 (Balanced Models) of the Modelica 3.0 specification.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.BaseProperties
.
Type | Name | Default | Description |
---|---|---|---|
Boolean | preferredMediumStates | false | = true if StateSelect.prefer shall be used for the independent property variables of the medium |
final Boolean | standardOrderComponents | true | If true, and reducedX = true, the last element of X will be computed from the other ones |
Type | Name | Description |
---|---|---|
input InputAbsolutePressure | p | Absolute pressure of medium |
input InputMassFraction | Xi[nXi] | Structurally independent mass fractions |
input InputSpecificEnthalpy | h | Specific enthalpy of medium |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
Temperature | T | Temperature |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
ThermodynamicState | state |   |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEnthalpy | h | Specific enthalpy |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
ThermodynamicState | state |   |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEntropy | s | Specific entropy |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
ThermodynamicState | state |   |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
Density | d | Density |
Temperature | T | Temperature |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
ThermodynamicState | state |   |
This function is used to approximate the equation
state = if x > 0 then state_a else state_b;
by a smooth characteristic, so that the expression is continuous and differentiable:
state := smooth(1, if x > x_small then state_a else if x < -x_small then state_b else f(state_a, state_b));
This is performed by applying function Media.Common.smoothStep(..) on every element of the thermodynamic state record.
If mass fractions X[:] are approximated with this function then this can be performed for all nX mass fractions, instead of applying it for nX-1 mass fractions and computing the last one by the mass fraction constraint sum(X)=1. The reason is that the approximating function has the property that sum(state.X) = 1, provided sum(state_a.X) = sum(state_b.X) = 1. This can be shown by evaluating the approximating function in the abs(x) < x_small region (otherwise state.X is either state_a.X or state_b.X):
X[1] = smoothStep(x, X_a[1] , X_b[1] , x_small); X[2] = smoothStep(x, X_a[2] , X_b[2] , x_small); ... X[nX] = smoothStep(x, X_a[nX], X_b[nX], x_small);
or
X[1] = c*(X_a[1] - X_b[1]) + (X_a[1] + X_b[1])/2 X[2] = c*(X_a[2] - X_b[2]) + (X_a[2] + X_b[2])/2; ... X[nX] = c*(X_a[nX] - X_b[nX]) + (X_a[nX] + X_b[nX])/2; c = (x/x_small)*((x/x_small)^2 - 3)/4
Summing all mass fractions together results in
sum(X) = c*(sum(X_a) - sum(X_b)) + (sum(X_a) + sum(X_b))/2 = c*(1 - 1) + (1 + 1)/2 = 1
Extends from Modelica.Media.Interfaces.PartialPureSubstance.setSmoothState
(Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b).
Type | Name | Description |
---|---|---|
Real | x | m_flow or dp |
ThermodynamicState | state_a | Thermodynamic state if x > 0 |
ThermodynamicState | state_b | Thermodynamic state if x < 0 |
Real | x_small | Smooth transition in the region -x_small < x < x_small |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Smooth thermodynamic state for all x (continuous and differentiable) |
Dynamic viscosity is computed from temperature using a simple polynomial for dry air. Range of validity is from 123.15 K to 1273.15 K. The influence of pressure is neglected.
Source: VDI Waermeatlas, 8th edition.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
DynamicViscosity | eta | Dynamic viscosity |
Thermal conductivity is computed from temperature using a simple polynomial for dry air. Range of validity is from 123.15 K to 1273.15 K. The influence of pressure is neglected.
Source: VDI Waermeatlas, 8th edition.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Integer | method | Dummy for compatibility reasons |
Type | Name | Description |
---|---|---|
ThermalConductivity | lambda | Thermal conductivity |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
PrandtlNumber | Pr | Prandtl number |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.pressure
(Return pressure).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.temperature
(Return temperature).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.density
(Return density).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
Density | d | Density |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.specificEnthalpy
(Return specific enthalpy) and Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.specificInternalEnergy
(Return specific internal energy) and Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | u | Specific internal energy |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.specificEntropy
(Return specific entropy) and Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEntropy | s | Specific entropy |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.specificGibbsEnergy
(Return specific Gibbs energy) and Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | g | Specific Gibbs energy |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.specificHelmholtzEnergy
(Return specific Helmholtz energy) and Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | f | Specific Helmholtz energy |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.specificHeatCapacityCp
(Return specific heat capacity at constant pressure).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cp | Specific heat capacity at constant pressure |
This icon indicates Modelica functions.
Extends from Modelica.Media.Air.DryAirNasa.specificHeatCapacityCp
(Return specific heat capacity at constant pressure).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cp | Specific heat capacity at constant pressure |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.specificHeatCapacityCv
(Return specific heat capacity at constant volume).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cv | Specific heat capacity at constant volume |
This icon indicates Modelica functions.
Extends from Modelica.Media.Air.DryAirNasa.specificHeatCapacityCv
(Compute specific heat capacity at constant volume from temperature and gas data).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cv | Specific heat capacity at constant volume |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.isentropicExponent
(Return isentropic exponent).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
IsentropicExponent | gamma | Isentropic exponent |
This function computes an isentropic state transformation:
Extends from Modelica.Media.Interfaces.PartialPureSubstance.isentropicEnthalpy
(Return isentropic enthalpy).
Type | Name | Description |
---|---|---|
AbsolutePressure | p_downstream | Downstream pressure |
ThermodynamicState | refState | Reference state for entropy |
Boolean | exclEnthForm | If true, enthalpy of formation Hf is not included in specific enthalpy h |
ReferenceEnthalpy | refChoice | Choice of reference enthalpy |
SpecificEnthalpy | h_off | User defined offset for reference enthalpy, if referenceChoice = UserDefined |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h_is | Isentropic enthalpy |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.velocityOfSound
(Return velocity of sound) and Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
VelocityOfSound | a | Velocity of sound |
beta is defined as 1/v * der(v,T), with v = 1/d, at constant pressure p.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.isobaricExpansionCoefficient
(Return overall the isobaric expansion coefficient beta).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
IsobaricExpansionCoefficient | beta | Isobaric expansion coefficient |
beta is defined as 1/v * der(v,T), with v = 1/d, at constant pressure p.
Extends from Modelica.Media.Air.DryAirNasa.isobaricExpansionCoefficient
(Returns overall the isobaric expansion coefficient beta).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
IsobaricExpansionCoefficient | beta | Isobaric expansion coefficient |
kappa is defined as - 1/v * der(v,p), with v = 1/d at constant temperature T.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.isothermalCompressibility
(Return overall the isothermal compressibility factor).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
IsothermalCompressibility | kappa | Isothermal compressibility |
kappa is defined as - 1/v * der(v,p), with v = 1/d at constant temperature T.
Extends from Modelica.Media.Air.DryAirNasa.isothermalCompressibility
(Returns overall the isothermal compressibility factor).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
IsothermalCompressibility | kappa | Isothermal compressibility |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
DerDensityByPressure | ddph | Density derivative w.r.t. pressure |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
DerDensityByEnthalpy | ddhp | Density derivative w.r.t. specific enthalpy |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.density_derp_T
(Return density derivative w.r.t. pressure at const temperature).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
DerDensityByPressure | ddpT | Density derivative w.r.t. pressure |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.density_derT_p
(Return density derivative w.r.t. temperature at constant pressure).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
DerDensityByTemperature | ddTp | Density derivative w.r.t. temperature |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.density_derX
(Return density derivative w.r.t. mass fraction).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
Density | dddX[nX] | Derivative of density w.r.t. mass fraction |
This icon indicates Modelica functions.
Extends from Modelica.Media.Interfaces.PartialPureSubstance.molarMass
(Return the molar mass of the medium).
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
MolarMass | MM | Mixture molar mass |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
Temperature | T | Temperature |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
Temperature | T | Temperature |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
SpecificEntropy | s | Specific entropy |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
Temperature | T | Temperature |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
Density | d | Density |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEnthalpy | h | Specific enthalpy |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEnthalpy | h | Specific enthalpy |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
Density | d | Density |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEntropy | s | Specific entropy |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEntropy | s | Specific entropy |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
Density | d | Density |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEntropy | s | Specific entropy |
MassFraction | X[:] | Mass fractions |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy |
Extends from Modelica.SIunits.MassFlowRate
.
Name | Value |
---|---|
quantity | "MassFlowRate." + mediumName |
unit | "kg/s" |
min | -100000 |
max | 100000 |
start | 0. |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
Temperature | T | Temperature |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEnthalpy | h | Specific enthalpy |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEntropy | s | Specific entropy |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
Density | d | Density |
Temperature | T | Temperature |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state record |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEnthalpy | h | Specific enthalpy |
Type | Name | Description |
---|---|---|
Density | d | Density |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEnthalpy | h | Specific enthalpy |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
Density | d | Density |
Temperature | T | Temperature |
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
Density | d | Density |
Temperature | T | Temperature |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEntropy | s | Specific entropy |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEntropy | s | Specific entropy |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEntropy | s | Specific entropy |
Type | Name | Description |
---|---|---|
Density | d | Density |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
Temperature | T | Temperature |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
Temperature | T | Temperature |
Type | Name | Description |
---|---|---|
Density | d | Density |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
Pressure | p2 | Downstream pressure |
ThermodynamicState | state | Properties at upstream location |
Boolean | exclEnthForm | If true, enthalpy of formation Hf is not included in specific enthalpy h |
ReferenceEnthalpy | refChoice | Choice of reference enthalpy |
SpecificEnthalpy | h_off | User defined offset for reference enthalpy, if referenceChoice = UserDefined |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h_is | Isentropic enthalpy |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature |
This icon indicates Modelica functions.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure |
SpecificEntropy | s | Specific entropy |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature |
The used formula are based on the method of Chung et al (1984, 1988) referred to in ref [1] chapter 9. The formula 9-4.10 is the one being used. The Formula is given in non-SI units, the following conversion constants were used to transform the formula to SI units:
[1] Bruce E. Poling, John E. Prausnitz, John P. O'Connell, "The Properties of Gases and Liquids" 5th Ed. Mc Graw Hill.
T. Skoglund, Lund, Sweden, 2004-08-31
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
Temp_K | T | Gas temperature |
Temp_K | Tc | Critical temperature of gas |
MolarMass | M | Molar mass of gas |
MolarVolume | Vc | Critical molar volume of gas |
Real | w | Acentric factor of gas |
DipoleMoment | mu | Dipole moment of gas molecule |
Real | k | Special correction for highly polar substances |
Type | Name | Description |
---|---|---|
DynamicViscosity | eta | Dynamic viscosity of gas |
This function provides two similar methods for estimating the
thermal conductivity of polyatomic gases.
The Eucken method (input method == 1) gives good results for low temperatures,
but it tends to give an underestimated value of the thermal conductivity
(lambda) at higher temperatures.
The Modified Eucken method (input method == 2) gives good results for
high-temperatures, but it tends to give an overestimated value of the
thermal conductivity (lambda) at low temperatures.
Extends from Modelica.Icons.Function
(Icon for functions).
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | Cp | Constant pressure heat capacity |
DynamicViscosity | eta | Dynamic viscosity |
Integer | method | 1: Eucken Method, 2: Modified Eucken Method |
DataRecord | data | Ideal gas data |
Type | Name | Description |
---|---|---|
ThermalConductivity | lambda | Thermal conductivity [W/(m.k)] |
Generated 2018-12-12 12:13:47 EST by MapleSim.