Psychrometric Properties of Humid Air from Multi-Fluid Helmholtz-Free-Energy-Explicit Models

Published

July 11, 2016

Author(s)

Ian H. Bell, Eric W. Lemmon, Allan H. Harvey

Abstract

Psychrometric properties of humid air are widely used in the analysis and modeling of thermal systems. In this work we present a method for obtaining these properties from the multi-fluid mixture formulation forming the so-called GERG mixture model. This mixture model was originally developed to model the thermodynamics of natural gas mixtures, and now has been extended to model thermodynamic properties relevant for carbon capture and storage. The primary advantage of this formulation is that the dry air composition is not fixed, and can be adjusted to suit the application, for instance in submarines, for Martian atmospheres, etc. We present an algorithm that can be used to calculate the saturated vapor water composition in vapor-liquid equilibrium, and other properties that arise out of this equilibrium calculation, like relative humidity and dewpoints. Solid-vapor equilibrium is not considered, and neither is the calculation of wet-bulb temperatures.

Proceedings Title

16th International Refrigeration and Air Conditioning Conference at Purdue, July 11-14, 2016

Conference Dates

July 11-14, 2016

Conference Location

West Lafayette, IN

Pub Type

Conferences

Keywords

psychrometry, humid air, mixture modeling, vapor-liquid equilibria

Citation

Bell, I. , Lemmon, E. and Harvey, A. (2016), Psychrometric Properties of Humid Air from Multi-Fluid Helmholtz-Free-Energy-Explicit Models, 16th International Refrigeration and Air Conditioning Conference at Purdue, July 11-14, 2016, West Lafayette, IN (Accessed April 20, 2024)