modelPartialIdealGas

Base class for adiabatic thermodynamic models assuming an ideal gas (p*v = R*T)

Extends from ThermofluidStream.Idealized.Processes.AdiabaticThermodynamicModels.BaseClasses.PartialAdiabatic (Base class for adiabatic thermodynamic models for given outlet pressure).

Information

Base model of an adiabatic process. The model is supposed to compute the outlet specific enthalpy based on:

  • Inlet state
  • Outlet pressure
  • Isentropic efficiency

The model assumes ideal gas p*v = R*T and constant isentropic exponent gamma = const..

Parameters

TypeNameDefaultDescription
StringnamegetInstanceName()
Assumptions
ThermodynamicValueSpecificationgammaSpecThermofluidStream.Types.ThermodynamicValueSpecification.StateSpecifies whether the isentropic exponent is fixed or obtained from the inlet state
Medium.IsentropicExponentgamma_fixed1.4Fixed isentropic exponent
Warnings
AssertionLevelassertionLevelAssertionLevel.warningAssertion level
RealrelTolZ0.05Relative tolerance of compressibility factor at inlet and outlet (tolerance for ideal gas behaviour)
RealrelTolGamma1e-2Relative tolerance for isentropic exponent gamma_in, gamma_out

Components

TypeNameDefaultDescription
Medium.ThermodynamicStatestate_in (from PartialAdiabatic)Inlet state
Medium.AbsolutePressurep_out (from PartialAdiabatic)Outlet pressure
SI.Efficiencyeta_is (from PartialAdiabatic)Isentropic efficiency
Medium.SpecificEnthalpyh_out (from PartialAdiabatic)Outlet specific enthalpy
SI.SpecificEnthalpyw_t (from PartialAdiabatic)Specific technical work
SI.SpecificEnthalpyw_t_is (from PartialAdiabatic)Specific isentropic technical work
Medium.AbsolutePressurep_in (from PartialAdiabatic)Medium.pressure(state_in)Inlet pressure
Medium.MassFraction[Medium.nXi]Xi_in (from PartialAdiabatic)Medium.massFraction(state_in)Inlet mass fractions
Medium.TemperatureT_inMedium.temperature(state_in)Inlet temperature
Medium.TemperatureT_out_isIsentropic outlet temperature
Medium.IsentropicExponentgammaIsentropic exponent
Medium.IsentropicExponentgamma_inMedium.isentropicExponent(state_in)Isentropic exponent (inlet)
Medium.IsentropicExponentgamma_outMedium.isentropicExponent(Medium.setState_phX(p_out, h_out, Xi_in))Isentropic exponent (outlet)
Realdelta_gamma_relabs(gamma_out - gamma_in)/max(gamma_out, gamma_in)Relative difference of isentropic exponents gamma_in, gamma_out
RealZ_inCompressibility factor at inlet
RealZ_outCompressibility factor at outlet
Medium.ThermodynamicStatestate_outMedium.setState_phX(p_out, h_out, Xi_in)Outlet state
SI.Densityrho_inMedium.density(state_in)Inlet density
SI.Densityrho_outMedium.density(state_out)Outlet density
SI.MolarMassMMedium.molarMass(state_in)Molar mass
RealisInletIdealGassign(Z_in - 1/(1 + relTolZ))*sign(1 + relTolZ - Z_in)= 1.0 if Z_in within tolerance, = -1.0 if tolerance is exceeded
RealisOutletIdealGassign(Z_out - 1/(1 + relTolZ))*sign(1 + relTolZ - Z_out)= 1.0 if Z_out within tolerance, = -1.0 if tolerance is exceeded
RealisGammaWithinTolsign(relTolGamma - delta_gamma_rel)= 1.0 if gamma within tolerance, = -1.0 if tolerance is exceeded

Revisions

  • 2026, by Raphael Gebhart (raphael.gebhart@dlr.de):
    Initial version.