Library logo

Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater

Package with model for ethylene glycol - water with constant properties

Information

This medium package models ethylene glycol - water mixtures.

These functions are identical with the ones in Buildings.Media.Antifreeze.EthyleneGlycolWater. See therefore the documentation of that package.

Extends from Modelica.Icons.Package (Icon for standard packages).

Package Content

Name Description
X_a_min=0. Minimum allowed mass fraction of ethylene glycol in water
X_a_max=0.6 Maximum allowed mass fraction of ethylene glycol in water
Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.density_TX_a density_TX_a Evaluate density of antifreeze-water mixture
Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.dynamicViscosity_TX_a dynamicViscosity_TX_a Evaluate dynamic viscosity of antifreeze-water mixture
Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.fusionTemperature_TX_a fusionTemperature_TX_a Evaluate temperature of fusion of antifreeze-water mixture
Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.polynomialProperty polynomialProperty Evaluates thermophysical property from 2-variable polynomial
Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.prandtlNumber_TX_a prandtlNumber_TX_a Evaluate Prandtl number of antifreeze-water mixture
Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.specificHeatCapacityCp_TX_a specificHeatCapacityCp_TX_a Evaluate specific heat capacity of antifreeze-water mixture
Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.thermalConductivity_TX_a thermalConductivity_TX_a Evaluate thermal conductivity of antifreeze-water mixture
Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.volumeToMassFraction volumeToMassFraction Returns the mass fraction of the mixture for a given volume fraction
Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.proCoe proCoe Coefficients for evaluation of thermo-physical properties

Types and constants

  constant Modelica.Units.SI.MassFraction X_a_min=0.
    "Minimum allowed mass fraction of ethylene glycol in water";
  constant Modelica.Units.SI.MassFraction X_a_max=0.6
    "Maximum allowed mass fraction of ethylene glycol in water";

Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.density_TX_a Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.density_TX_a

Evaluate density of antifreeze-water mixture

Information

Density of ethylene antifreeze-water mixture at specified mass fraction and temperature, based on Melinder (2010).

References

Melinder, Åke. 2010. Properties of Secondary Working Fluids (Secondary Refrigerants or Coolants, Heat Transfer Fluids) for Indirect Systems. Paris: IIR/IIF.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

TypeNameDefaultDescription
TemperatureT Temperature of antifreeze-water mixture [K]
MassFractionX_a Mass fraction of antifreeze [1]

Outputs

TypeNameDescription
DensitydDensity of antifreeze-water mixture [kg/m3]

Modelica definition

function density_TX_a "Evaluate density of antifreeze-water mixture" extends Modelica.Icons.Function; input Modelica.Units.SI.Temperature T "Temperature of antifreeze-water mixture"; input Modelica.Units.SI.MassFraction X_a "Mass fraction of antifreeze"; output Modelica.Units.SI.Density d "Density of antifreeze-water mixture"; algorithm d :=polynomialProperty( X_a, T, proCoe.a_d); end density_TX_a;

Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.dynamicViscosity_TX_a Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.dynamicViscosity_TX_a

Evaluate dynamic viscosity of antifreeze-water mixture

Information

Dynamic viscosity of antifreeze-water mixture at specified mass fraction and temperature, based on Melinder (2010).

References

Melinder, Åke. 2010. Properties of Secondary Working Fluids (Secondary Refrigerants or Coolants, Heat Transfer Fluids) for Indirect Systems. Paris: IIR/IIF.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

TypeNameDefaultDescription
TemperatureT Temperature of antifreeze-water mixture [K]
MassFractionX_a Mass fraction of antifreeze [1]

Outputs

TypeNameDescription
DynamicViscosityetaDynamic Viscosity of antifreeze-water mixture [Pa.s]

Modelica definition

function dynamicViscosity_TX_a "Evaluate dynamic viscosity of antifreeze-water mixture" extends Modelica.Icons.Function; input Modelica.Units.SI.Temperature T "Temperature of antifreeze-water mixture"; input Modelica.Units.SI.MassFraction X_a "Mass fraction of antifreeze"; output Modelica.Units.SI.DynamicViscosity eta "Dynamic Viscosity of antifreeze-water mixture"; algorithm eta :=1e-3*exp(polynomialProperty( X_a, T, proCoe.a_eta)); end dynamicViscosity_TX_a;

Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.fusionTemperature_TX_a Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.fusionTemperature_TX_a

Evaluate temperature of fusion of antifreeze-water mixture

Information

Fusion temperature of antifreeze-water mixture at specified mass fraction and temperature, based on Melinder (2010).

References

Melinder, Åke. 2010. Properties of Secondary Working Fluids (Secondary Refrigerants or Coolants, Heat Transfer Fluids) for Indirect Systems. Paris: IIR/IIF.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

TypeNameDefaultDescription
TemperatureT Temperature of antifreeze-water mixture [K]
MassFractionX_a Mass fraction of antifreeze [1]

Outputs

TypeNameDescription
TemperatureTfTemperature of fusion of antifreeze-water mixture [K]

Modelica definition

function fusionTemperature_TX_a "Evaluate temperature of fusion of antifreeze-water mixture" extends Modelica.Icons.Function; input Modelica.Units.SI.Temperature T "Temperature of antifreeze-water mixture"; input Modelica.Units.SI.MassFraction X_a "Mass fraction of antifreeze"; output Modelica.Units.SI.Temperature Tf "Temperature of fusion of antifreeze-water mixture"; algorithm Tf :=Modelica.Units.Conversions.from_degC(polynomialProperty( X_a, T, proCoe.a_Tf)); end fusionTemperature_TX_a;

Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.polynomialProperty Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.polynomialProperty

Evaluates thermophysical property from 2-variable polynomial

Information

Evaluates a thermophysical property of a mixture, based on correlations proposed by Melinder (2010).

The polynomial has the form

f = a1 (x-xm)0(y-ym)0 + a2 (x-xm)0(y-ym)1 + ... + any[1] (x-xm)0(y-ym)ny[1]-1 + ... + any[1])+1 (x-xm)1(y-ym)0 + ... + any[1]+ny[2] (x-xm)1(y-ym)ny[2]-1 + ...

References

Melinder, Åke. 2010. Properties of Secondary Working Fluids (Secondary Refrigerants or Coolants, Heat Transfer Fluids) for Indirect Systems. Paris: IIR/IIF.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

TypeNameDefaultDescription
Realx First independent variable
Realy Second independent variable
Reala[sum(proCoe.nT)] Polynomial coefficients

Outputs

TypeNameDescription
RealfValue of thermophysical property

Modelica definition

function polynomialProperty "Evaluates thermophysical property from 2-variable polynomial" extends Modelica.Icons.Function; input Real x "First independent variable"; input Real y "Second independent variable"; input Real a[sum(proCoe.nT)] "Polynomial coefficients"; output Real f "Value of thermophysical property"; protected Real dx; Real dy; Integer n; algorithm dx := 100*(x - proCoe.X_a_ref); dy := y - proCoe.T_ref; f := 0; n := 0; for i in 0:proCoe.nX_a - 1 loop for j in 0:proCoe.nT[i+1] - 1 loop n := n + 1; f := f + a[n]*dx^i*dy^j; end for; end for; end polynomialProperty;

Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.prandtlNumber_TX_a Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.prandtlNumber_TX_a

Evaluate Prandtl number of antifreeze-water mixture

Information

Prandtl number of antifreeze-water mixture at specified mass fraction and temperature, based on Melinder (2010).

References

Melinder, Åke. 2010. Properties of Secondary Working Fluids (Secondary Refrigerants or Coolants, Heat Transfer Fluids) for Indirect Systems. Paris: IIR/IIF.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

TypeNameDefaultDescription
TemperatureT Temperature of antifreeze-water mixture [K]
MassFractionX_a Mass fraction of antifreeze [1]

Outputs

TypeNameDescription
ThermalConductivityPrPrandtl number of antifreeze-water mixture [W/(m.K)]

Modelica definition

function prandtlNumber_TX_a "Evaluate Prandtl number of antifreeze-water mixture" extends Modelica.Icons.Function; input Modelica.Units.SI.Temperature T "Temperature of antifreeze-water mixture"; input Modelica.Units.SI.MassFraction X_a "Mass fraction of antifreeze"; output Modelica.Units.SI.ThermalConductivity Pr "Prandtl number of antifreeze-water mixture"; algorithm Pr := dynamicViscosity_TX_a(T=T, X_a=X_a) * specificHeatCapacityCp_TX_a(T=T, X_a=X_a) / thermalConductivity_TX_a(T=T, X_a=X_a); end prandtlNumber_TX_a;

Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.specificHeatCapacityCp_TX_a Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.specificHeatCapacityCp_TX_a

Evaluate specific heat capacity of antifreeze-water mixture

Information

Specific heat capacity of antifreeze-water mixture at specified mass fraction and temperature, based on Melinder (2010).

References

Melinder, Åke. 2010. Properties of Secondary Working Fluids (Secondary Refrigerants or Coolants, Heat Transfer Fluids) for Indirect Systems. Paris: IIR/IIF.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

TypeNameDefaultDescription
TemperatureT Temperature of antifreeze-water mixture [K]
MassFractionX_a Mass fraction of antifreeze [1]

Outputs

TypeNameDescription
SpecificHeatCapacitycpSpecific heat capacity of antifreeze-water mixture [J/(kg.K)]

Modelica definition

function specificHeatCapacityCp_TX_a "Evaluate specific heat capacity of antifreeze-water mixture" extends Modelica.Icons.Function; input Modelica.Units.SI.Temperature T "Temperature of antifreeze-water mixture"; input Modelica.Units.SI.MassFraction X_a "Mass fraction of antifreeze"; output Modelica.Units.SI.SpecificHeatCapacity cp "Specific heat capacity of antifreeze-water mixture"; algorithm cp :=polynomialProperty( X_a, T, proCoe.a_cp); end specificHeatCapacityCp_TX_a;

Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.thermalConductivity_TX_a Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.thermalConductivity_TX_a

Evaluate thermal conductivity of antifreeze-water mixture

Information

Thermal conductivity of antifreeze-water mixture at specified mass fraction and temperature, based on Melinder (2010).

References

Melinder, Åke. 2010. Properties of Secondary Working Fluids (Secondary Refrigerants or Coolants, Heat Transfer Fluids) for Indirect Systems. Paris: IIR/IIF.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

TypeNameDefaultDescription
TemperatureT Temperature of antifreeze-water mixture [K]
MassFractionX_a Mass fraction of antifreeze [1]

Outputs

TypeNameDescription
ThermalConductivitylambdaThermal conductivity of antifreeze-water mixture [W/(m.K)]

Modelica definition

function thermalConductivity_TX_a "Evaluate thermal conductivity of antifreeze-water mixture" extends Modelica.Icons.Function; input Modelica.Units.SI.Temperature T "Temperature of antifreeze-water mixture"; input Modelica.Units.SI.MassFraction X_a "Mass fraction of antifreeze"; output Modelica.Units.SI.ThermalConductivity lambda "Thermal conductivity of antifreeze-water mixture"; algorithm lambda :=polynomialProperty( X_a, T, proCoe.a_lambda); end thermalConductivity_TX_a;

Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.volumeToMassFraction Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.volumeToMassFraction

Returns the mass fraction of the mixture for a given volume fraction

Information

Conversion from volume fraction to mass fraction of antifreeze-water mixture at specified temperature.

Implementation

The density function is only valid for mass fractions up to X_a_max. Therefore, linear extrapolation, using the slope of the density function at X_a_max, is used to get the density of glycol at X_a=1.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

TypeNameDefaultDescription
Realphi Volume fraction of the mixture [1]
TemperatureT Temperature of antifreeze-water mixture [K]

Outputs

TypeNameDescription
SpecificVolumeyMass fraction of the mixture [m3/kg]

Modelica definition

function volumeToMassFraction "Returns the mass fraction of the mixture for a given volume fraction" extends Modelica.Icons.Function; input Real phi( final min=0, max=1, final unit="1") "Volume fraction of the mixture"; input Modelica.Units.SI.Temperature T "Temperature of antifreeze-water mixture"; output Modelica.Units.SI.SpecificVolume y( min=X_a_min, max=X_a_max) "Mass fraction of the mixture"; protected constant Real delta = 0.01 "Small increment for numerical differentiation"; Modelica.Units.SI.Density dWat "Mass density of water"; Modelica.Units.SI.Density dGly "Mass density of glycol"; Modelica.Units.SI.Density phiRhoGly "Fraction of mass density of glycol"; Modelica.Units.SI.Density dMix "Mass density of the mixture"; algorithm dWat := density_TX_a(T=T, X_a=0); // The density function is only valid for mass fractions up to X_a_max, // so we use linear extrapolation to get the density of glycol at X_a=1 dGly := density_TX_a(T=T, X_a=X_a_max) + (1.0-X_a_max) * (density_TX_a(T=T, X_a=X_a_max)-density_TX_a(T=T, X_a=X_a_max-delta)) / delta; phiRhoGly := phi * dGly; dMix := phiRhoGly + (1-phi) * dWat; y := phiRhoGly / dMix; end volumeToMassFraction;

Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.proCoe Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.proCoe

Coefficients for evaluation of thermo-physical properties

Information

Record that is used by media packages in Buildings.Media.Antifreeze to implement the thermophysical properties based on Melinder (2010).

References

Melinder, Åke. 2010. Properties of Secondary Working Fluids (Secondary Refrigerants or Coolants, Heat Transfer Fluids) for Indirect Systems. Paris: IIR/IIF.

Extends from Modelica.Icons.Record (Icon for records).

Modelica definition

record proCoe "Coefficients for evaluation of thermo-physical properties" extends Modelica.Icons.Record; constant Modelica.Units.SI.MassFraction X_a_ref=0.308462 "Reference mass fraction"; constant Modelica.Units.SI.Temperature T_ref=Modelica.Units.Conversions.from_degC(31.728) "Reference temperature"; constant Integer nX_a=6 "Order of polynomial in x"; constant Integer nT[nX_a]={4,4,4,3,2,1} "Order of polynomial in y"; constant Integer nTot=18 "Total number of coefficients"; constant Real a_d[nTot]= {1.034e3,-4.781e-1,-2.692e-3,4.725e-6,1.311e0,-6.876e-3,4.805e-5, 1.690e-8,7.490e-5,7.855e-5,-3.995e-7,4.982e-9,-1.062e-4,1.229e-6,-1.153e-8, -9.623e-7,-7.221e-8,4.891e-8} "Polynomial coefficients for density"; constant Real a_eta[nTot]= {4.705e-1,-2.550e-2,1.782e-4,-7.669e-7,2.471e-2,-1.171e-4,1.052e-6,-1.634e-8, 3.328e-6,-1.086e-6,-1.051e-8,-6.475e-10,1.695e-6,3.157e-9,4.063e-10, 3.089e-8,1.831e-10,-1.865e-9} "Polynomial coefficients for dynamic viscosity"; constant Real a_Tf[nTot]= {-1.525e1,-1.566e-6,-2.278e-7,2.169e-9,-8.080e-1,-1.339e-6,2.047e-08,-2.717e-11, -1.334e-2,6.332e-8,2.373e-10,-2.183e-12,-7.293e-5,-1.764e-9,-2.442e-11, 1.006e-6,-7.662e-11,1.140e-9} "Polynomial coefficients for fusion temperature"; constant Real a_cp[nTot]= {3.737e3,2.930e0,-4.675e-3,-1.389e-5,-1.799e1,1.046e-1,-4.147e-4, 1.847e-7,-9.933e-2,3.516e-4,5.109e-6,-7.138e-8,2.610e-3,-1.189e-6,-1.643e-7, 1.537e-5,-4.272e-7,-1.618e-6} "Polynomial coefficients for specific heat capacity"; constant Real a_lambda[nTot]= {4.720e-1,8.903e-4,-1.058e-6,-2.789e-9,-4.286e-3,-1.473e-5, 1.059e-7,-1.142e-10,1.747e-5,6.814e-8,-3.612e-9,2.365e-12,3.017e-8,-2.412e-9, 4.004e-11,-1.322e-09,2.555e-11,2.678e-11} "Polynomial coefficients for thermal conductivity"; end proCoe;