Detailed Description

Specific gas constant $ R_\mathrm{s} = R/M $. $M$ is the molar mass. The unit of $ R_\mathrm{s} $ is J kg^-1 K^-1.

Variables
constexpr double	WaterVapour
	Specific gas constant for water vapour.
constexpr double	WaterIF97 = 461.526
	J kg^-1 K^-1

Variable Documentation

◆ WaterIF97

double MaterialLib::PhysicalConstant::SpecificGasConstant::WaterIF97 = 461.526

constexpr

J kg^-1 K^-1

Specific gas constant of ordinary water as defined for IAPWS-IF97.

This is not a measured physical constant and must not be replaced by WaterVapour or updated to newer CODATA values: the regression coefficients of IF97 were fitted with this value held fixed, so it is a defined parameter of the formulation in the same sense as its reducing quantities $p^*$ and $T^*$. Using any other value makes the IF97 equations disagree with their own published verification tables.

Source: IAPWS R7-97(2012), "Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam", Sec. 3 "Reference Constants", Eq. (1). http://www.iapws.org/relguide/IF97-Rev.pdf

Definition at line 147 of file PhysicalConstant.h.

Referenced by MaterialPropertyLib::WaterEnthalpyIAPWSIF97Region1::dValue(), MaterialPropertyLib::WaterDensityIAPWSIF97Region1::value(), MaterialPropertyLib::WaterEnthalpyIAPWSIF97Region1::value(), MaterialPropertyLib::WaterLiquidDensityIAPWSIF97Region4::value(), MaterialPropertyLib::WaterLiquidEnthalpyIAPWSIF97Region4::value(), MaterialPropertyLib::WaterVapourDensityIAPWSIF97Region4::value(), and MaterialPropertyLib::WaterVapourEnthalpyIAPWSIF97Region4::value().