3319 -- Thermodynamic Properties of Ammonia-Water Mixtures: A Generalized Equation-of-State Approach PDF

The thermodynamic properties of the mixtures are calculated based on a generalised equation of state developed by the authors. As the vapour compositions are calculated in a general and consistent manner, satisfying the theoretical requirement for vapour-liquid equilibrium data, no discontinuities or gaps exists in the thermodynamic and volumetric properties,. The results are smooth over the entire range and comparable with other previous results. For the calculation of thermodynamic properties such as enthalpy and entropy, this study avoids any suspect assumptions, yielding a consistent set of data comparable with other results. The comparison of bubble-point temperatures, enthalpy, and entropy with previous works is presented to investigate the accuracy of the new approach. The range of pressure is extended to 20 MPa and that of temperature goes to about 650 K for the saturation tables with appropriate concentration of ammonia. For the superheated region, the temperature range is easily extended to the limit of chemical stability in principle.

KEYWORDS: thermodynamics, properties, absorption refrigeration, cyclic, ammonia, water, data, calculating, analysis, comparing, entropy, heat content, saturation temperature.