Calculation of thermodynamic properties for refrigerants
Jurij Avsec, Milan Marčič
For the Lennard-Jones fluid, a mathematical model for computing thermodynamic functions of state in the liquid and gas domain with the help of statistical thermodynamics is developed. To calculate the thermodynamic properties of real fluid, the Johnson – Zollweg – Gubbins model based on the modified Benedict – Webb – Rubin equation of state, Chunxi – Yigui – Jiufang (revisited Cotterman) equation of state based on simple perturbation theory, and complex Tang – Tong – Lu model based on the solution of the Ornstein – Zernike equation with the help of perturbation theory, were applied. The analytical results are compared with the experimental and thermodynamic data and models obtained by classical thermodynamics, and show relatively good agreement.