Critical Region Vapor-Liquid Equilibrium Model of Ammonia-Water

Published

September 1, 1999

Author(s)

James C. Rainwater, R Tillner-Roth

Abstract

Two distinct thermodynamic models, the modified Leung-Griffths (MLG) model and a multiparameter equation of state explicit in Helmholtz energy, are used to correlate high-pressure vapor-liquid equilibrium (VLE) of ammonia-water. In view of the absence of experimental coexisting density data in this region, results from the equation of state are used as input for an optimized MLG correlation. Then the MLG phase boundary is used as input for a revised equation of state optimization, and so on iteratively. After three iterations, the two correlations are in basic agreement except for a small region close to the critical locus, where they must disagree due to differing critical exponents. The final MLG model agrees well with most high-pressure VLE data, except for some data shown to be suspect for separate reasons.

Proceedings Title

Proceedings of the 13th International Conference on the Properties of Water and Steam

Conference Dates

September 11-17, 1999

Conference Location

Ottawa, CA

Conference Title

International Conference on the Properties of Water and Steam

Pub Type

Conferences

Keywords

ammonia-water, coexisting densities, Helmholtz equation of state, high pressure, Leung-Griffiths model, vapor-liquid equilibrium

Citation

Rainwater, J. and Tillner-Roth, R. (1999), Critical Region Vapor-Liquid Equilibrium Model of Ammonia-Water, Proceedings of the 13th International Conference on the Properties of Water and Steam, Ottawa, CA (Accessed April 19, 2024)