redeclare record extends ThermodynamicState "Thermodynamic state of ideal gas" AbsolutePressure p "Absolute pressure of medium"; Temperature T "Temperature of medium"; end ThermodynamicState;
redeclare record extends FluidConstants "fluid constants" end FluidConstants;
This is the most simple incompressible medium model, where specific enthalpy h and specific internal energy u are only a function of temperature T and all other provided medium quantities are assumed to be constant.
Extends from .
Type | Name | Default | Description |
---|---|---|---|
Advanced | |||
Boolean | preferredMediumStates | false | = true if StateSelect.prefer shall be used for the independent property variables of the medium |
redeclare replaceable model extends BaseProperties( T(stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default), p(stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default)) "Base properties of ideal gas" equation assert(T >= T_min and T <= T_max, " Temperature T (= " + String(T) + " K) is not in the allowed range (" + String(T_min) + " K <= T <= " + String(T_max) + " K) required from medium model \"" + mediumName + "\". "); h = specificEnthalpy_pTX(p,T,X); u = h-R*T; R = R_gas; d = p/(R*T); MM = MM_const; state.T = T; state.p = p;end BaseProperties;
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
Temperature | T | Temperature [K] | |
MassFraction | X[:] | reference_X | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | thermodynamic state record |
redeclare function setState_pTX "Return thermodynamic state from p, T, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input Temperature T "Temperature"; input MassFraction X[:]=reference_X "Mass fractions"; output ThermodynamicState state "thermodynamic state record"; algorithm state := ThermodynamicState(p=p,T=T); end setState_pTX;
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
SpecificEnthalpy | h | Specific enthalpy [J/kg] | |
MassFraction | X[:] | reference_X | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | thermodynamic state record |
redeclare function setState_phX "Return thermodynamic state from p, h, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input SpecificEnthalpy h "Specific enthalpy"; input MassFraction X[:]=reference_X "Mass fractions"; output ThermodynamicState state "thermodynamic state record"; algorithm state := ThermodynamicState(p=p,T=T0+h/cp_const); end setState_phX;
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
SpecificEntropy | s | Specific entropy [J/(kg.K)] | |
MassFraction | X[:] | reference_X | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | thermodynamic state record |
redeclare replaceable function setState_psX "Return thermodynamic state from p, s, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input SpecificEntropy s "Specific entropy"; input MassFraction X[:]=reference_X "Mass fractions"; output ThermodynamicState state "thermodynamic state record"; algorithm state := ThermodynamicState(p=p,T=Modelica.Math.exp(s/cp_const + Modelica.Math.log(reference_T)) + R_gas*Modelica.Math.log(p/reference_p)); end setState_psX;
Type | Name | Default | Description |
---|---|---|---|
Density | d | density [kg/m3] | |
Temperature | T | Temperature [K] | |
MassFraction | X[:] | reference_X | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | thermodynamic state record |
redeclare function setState_dTX "Return thermodynamic state from d, T, and X or Xi" extends Modelica.Icons.Function; input Density d "density"; input Temperature T "Temperature"; input MassFraction X[:]=reference_X "Mass fractions"; output ThermodynamicState state "thermodynamic state record"; algorithm state := ThermodynamicState(p=d*R_gas*T,T=T); end setState_dTX;
Type | Name | Default | 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) |
redeclare function extends setSmoothState "Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b" algorithm state := ThermodynamicState(p=Media.Common.smoothStep(x, state_a.p, state_b.p, x_small), T=Media.Common.smoothStep(x, state_a.T, state_b.T, x_small)); end setSmoothState;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure [Pa] |
redeclare function extends pressure "Return pressure of ideal gas" algorithm p := state.p; end pressure;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature [K] |
redeclare function extends temperature "Return temperature of ideal gas" algorithm T := state.T; end temperature;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
Density | d | Density [kg/m3] |
redeclare function extends density "Return density of ideal gas" algorithm d := state.p/(R_gas*state.T); end density;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy [J/kg] |
redeclare function extends specificEnthalpy "Return specific enthalpy" extends Modelica.Icons.Function; algorithm h := cp_const*(state.T-T0); end specificEnthalpy;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | u | Specific internal energy [J/kg] |
redeclare function extends specificInternalEnergy "Return specific internal energy" extends Modelica.Icons.Function; algorithm // u := (cp_const-R_gas)*(state.T-T0); u := cp_const*(state.T-T0) - R_gas*state.T; end specificInternalEnergy;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEntropy | s | Specific entropy [J/(kg.K)] |
redeclare function extends specificEntropy "Return specific entropy" extends Modelica.Icons.Function; algorithm s := cp_const*Modelica.Math.log(state.T/T0) - R_gas*Modelica.Math.log(state.p/reference_p); end specificEntropy;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | g | Specific Gibbs energy [J/kg] |
redeclare function extends specificGibbsEnergy "Return specific Gibbs energy" extends Modelica.Icons.Function; algorithm g := cp_const*(state.T-T0) - state.T*specificEntropy(state); end specificGibbsEnergy;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | f | Specific Helmholtz energy [J/kg] |
redeclare function extends specificHelmholtzEnergy "Return specific Helmholtz energy" extends Modelica.Icons.Function; algorithm f := (cp_const-R_gas)*(state.T-T0) - state.T*specificEntropy(state); end specificHelmholtzEnergy;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
DynamicViscosity | eta | Dynamic viscosity [Pa.s] |
redeclare function extends dynamicViscosity "Return dynamic viscosity" algorithm eta := eta_const; end dynamicViscosity;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
ThermalConductivity | lambda | Thermal conductivity [W/(m.K)] |
redeclare function extends thermalConductivity "Return thermal conductivity" algorithm lambda := lambda_const; end thermalConductivity;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cp | Specific heat capacity at constant pressure [J/(kg.K)] |
redeclare function extends specificHeatCapacityCp "Return specific heat capacity at constant pressure" algorithm cp := cp_const; end specificHeatCapacityCp;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cv | Specific heat capacity at constant volume [J/(kg.K)] |
redeclare function extends specificHeatCapacityCv "Return specific heat capacity at constant volume" algorithm cv := cv_const; end specificHeatCapacityCv;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
IsentropicExponent | gamma | Isentropic exponent [1] |
redeclare function extends isentropicExponent "Return isentropic exponent" algorithm gamma := cp_const/cv_const; end isentropicExponent;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
VelocityOfSound | a | Velocity of sound [m/s] |
redeclare function extends velocityOfSound "Return velocity of sound " algorithm a := sqrt(cp_const/cv_const*R_gas*state.T); end velocityOfSound;
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
Temperature | T | Temperature [K] | |
MassFraction | X[nX] | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy at p, T, X [J/kg] |
redeclare function specificEnthalpy_pTX "Return specific enthalpy from p, T, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input Temperature T "Temperature"; input MassFraction X[nX] "Mass fractions"; output SpecificEnthalpy h "Specific enthalpy at p, T, X"; algorithm h := cp_const*(T-T0); end specificEnthalpy_pTX;
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
SpecificEnthalpy | h | Specific enthalpy [J/kg] | |
MassFraction | X[nX] | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature [K] |
redeclare function temperature_phX "Return temperature from p, h, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input SpecificEnthalpy h "Specific enthalpy"; input MassFraction X[nX] "Mass fractions"; output Temperature T "Temperature"; algorithm T := h/cp_const + T0; end temperature_phX;
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
SpecificEnthalpy | h | Specific enthalpy [J/kg] | |
MassFraction | X[nX] | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
Density | d | density [kg/m3] |
redeclare function density_phX "Return density from p, h, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input SpecificEnthalpy h "Specific enthalpy"; input MassFraction X[nX] "Mass fractions"; output Density d "density"; algorithm d := density(setState_phX(p,h,X)); end density_phX;
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p_downstream | downstream pressure [Pa] | |
ThermodynamicState | refState | reference state for entropy |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h_is | Isentropic enthalpy [J/kg] |
redeclare function extends isentropicEnthalpy "Return isentropic enthalpy" algorithm /* s = cp_const*log(refState.T/T0) - R_gas*log(refState.p/reference_p) = cp_const*log(state.T/T0) - R_gas*log(p_downstream/reference_p) log(state.T) = log(refState.T) + (R_gas/cp_const)*(log(p_downstream/reference_p) - log(refState.p/reference_p)) = log(refState.T) + (R_gas/cp_const)*log(p_downstream/refState.p) = log(refState.T) + log( (p_downstream/refState.p)^(R_gas/cp_const) ) = log( refState.T*(p_downstream/refState.p)^(R_gas/cp_const) ) state.T = refstate.T*(p_downstream/refstate.p)^(R_gas/cp_const) */ h_is := cp_const*(refState.T*(p_downstream/refState.p)^(R_gas/cp_const) - T0); end isentropicEnthalpy;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
IsobaricExpansionCoefficient | beta | Isobaric expansion coefficient [1/K] |
redeclare function extends isobaricExpansionCoefficient "Returns overall the isobaric expansion coefficient beta" algorithm /* beta = 1/v * der(v,T), with v = 1/d, at constant pressure p: v = R*T/p der(v,T) = R/p beta = p/(R*T)*R/p = 1/T */ beta := 1/state.T; end isobaricExpansionCoefficient;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
IsothermalCompressibility | kappa | Isothermal compressibility [1/Pa] |
redeclare function extends isothermalCompressibility "Returns overall the isothermal compressibility factor" algorithm /* kappa = - 1/v * der(v,p), with v = 1/d at constant temperature T. v = R*T/p der(v,T) = -R*T/p^2 kappa = p/(R*T)*R*T/p^2 = 1/p */ kappa := 1/state.p; end isothermalCompressibility;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
DerDensityByPressure | ddpT | Density derivative w.r.t. pressure [s2/m2] |
redeclare function extends density_derp_T "Returns the partial derivative of density with respect to pressure at constant temperature" algorithm /* d = p/(R*T) ddpT = 1/(R*T) */ ddpT := 1/(R_gas*state.T); end density_derp_T;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
DerDensityByTemperature | ddTp | Density derivative w.r.t. temperature [kg/(m3.K)] |
redeclare function extends density_derT_p "Returns the partial derivative of density with respect to temperature at constant pressure" algorithm /* d = p/(R*T) ddpT = -p/(R*T^2) */ ddTp := -state.p/(R_gas*state.T*state.T); end density_derT_p;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
Density | dddX[nX] | Derivative of density w.r.t. mass fraction [kg/m3] |
redeclare function extends density_derX "Returns the partial derivative of density with respect to mass fractions at constant pressure and temperature" algorithm dddX := fill(0,nX); end density_derX;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
MolarMass | MM | Mixture molar mass [kg/mol] |
redeclare function extends molarMass "Returns the molar mass of the medium" algorithm MM := MM_const; end molarMass;