NEW FUNDAMENTAL EQUATION FOR THERMODYNAMIC PROPERTY CORRELATIONS.

Abstract

A new fundamental equation for correlation of thermodynamic property data for fluids is presented. The fundamental equation (equation of state) is explicit in Helmholtz energy and is readily adapted to system analysis applications. All thermodynamic properties are derived by differentiation of the fundamental equation. A comprehensive function containing up to 100 terms provides the basis for the correlation. The fundamental equation for a specific fluid is a subset of this comprehensive function. The individual terms of the comprehensive function may be easily changed by varying exponents of the functions of the independent variables. Functions for the calculation of derivative properties are given, and the incorporation of calorimetric information via ideal gas heat capacity equations is discussed. Applications to fluids of cryogenic interest include oxygen, nitrogen, argon, ethylene and neon. Coefficients for calculation of thermodynamic properties of these fluids taken from formulations published elsewhere are given.