Rapid and Accurate Calculation of Water and Steam Properties Using the Tabular Taylor Series Expansion Method

Abstract

In applications where both speed and accuracy of computation of thermodynamic properties are important and particularly where the independent variables are not those used in Helmholtz equations, direct use of such equations can be excessively time-consuming. This paper introduces the enthalpy-pressure version of the tabular Taylor series (TTSE) method, which has the accuracy and computing speed required for application in power industries. The IAPWS formulation for scientific use, IAPWS-95, was used as the basic Helmholtz equation. The speed and accuracy of the TTSE have been compared with the IAPWS formulation for industrial use, IAPWS-IF97, which has been developed to achieve high-speed calculation with good representation of IAPWS-95 values. Test results show that the TTSE accurately represents the basic equation and that the computation speed is higher than that of IF97.