This function applies the Masson and Saxena modification of the Wassiljewa Equation for the thermal conductivity for gas mixtures of n elements at low pressure.
For nonpolar gas mixtures errors will generally be less than 3 to 4%. For mixtures of nonpolar-polar and polar-polar gases, errors greater than 5 to 8% may be expected. For mixtures in which the sizes and polarities of the constituent molecules are not greatly different, the thermal conductivity can be estimated satisfactorily by a mole fraction average of the pure component conductivities.
function lowPressureThermalConductivity extends Modelica.Icons.Function; input MoleFraction[:] y "Mole fraction of the components in the gas mixture"; input Temperature T "Temperature"; input Temperature[size(y, 1)] Tc "Critical temperatures"; input AbsolutePressure[size(y, 1)] Pc "Critical pressures"; input MolarMass[size(y, 1)] M "Molecular weights"; input ThermalConductivity[size(y, 1)] lambda "Thermal conductivities of the pure gases"; output ThermalConductivity lambdam "Thermal conductivity of the gas mixture"; end lowPressureThermalConductivity;