“Partial pressures” of humid air in wide pressure and temperature ranges

Zidong WANG, Hanping CHEN, Shilie WENG

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PDF(317 KB)
Front. Energy ›› 2013, Vol. 7 ›› Issue (4) : 511-517. DOI: 10.1007/s11708-013-0281-7
RESEARCH ARTICLE

“Partial pressures” of humid air in wide pressure and temperature ranges

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Abstract

“Partial pressure” in humid air is a question very much concerned by scientists and no satisfactory answer has been found to date. This paper proposes a novel method to obtain the “partial pressures” of the water vapor and dry air in humid air. The results obtained by the proposed method are quite different from that obtained by Dalton’s partial pressure law. The fundamental behaviors of water vapor and dry air are studied in depth in wide pressure and temperature ranges. Semi-permeable membrane models are proposed and applied for both saturated and unsaturated humid air. “Improvement factors” are developed to quantitatively describe the magnitude of the interaction between dissimilar molecules. One discovery is that the “partial pressure” of the water vapor in saturated humid air equals Ps, rather than (f·Ps) which was formerly believed. The other is that the interaction between dissimilar molecules may be omitted when temperature is above “cutting-off temperature” for unsaturated humid air. This paper satisfactorily answers the quest of “partial pressures” in humid air from a new perspective.

Keywords

partial pressure / Dalton’s partial pressure law / humid air / saturated / unsaturated

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Zidong WANG, Hanping CHEN, Shilie WENG. “Partial pressures” of humid air in wide pressure and temperature ranges. Front Energ, 2013, 7(4): 511‒517 https://doi.org/10.1007/s11708-013-0281-7

References

[1]
Melling A, Noppenberger S, Still M, Venzke H. Interpolation correlation for fluid properties of humid air in the temperature range 100ºC to 200ºC. Journal of Physical and Chemical Reference Data, 1997, 26(4): 1111-1123
[2]
Kim T S, Song C H, Ro S T, Kauh S K. Influence of ambient condition on thermodynamic performance of the humid air turbine cycle. Energy, 2000, 25(4): 313-324
[3]
Perry R H, Green D W. Perry’s Chemical Engineers’ Handbook (7th edition). McGraw-Hill, 1997
[4]
Herrmann S, Kretzschmar H J, Gatley D P. Thermodynamic properties of real moist air, dry air, steam, water, and ice. International Journal of Heating, Ventilating, Air-Conditioning, and Refrigerating Research, 2009, 15(5): 961-986
[5]
Ji X, Lu X, Yan J. Survey of experimental data and assessment of calculation methods of properties for the air-water mixture. Applied Thermal Engineering, 2003, 23(17): 2213-2228
[6]
Wagner W, Pruss A. The IAPWS formulation 1995 for the thermodynamic properties of ordinary water substance for general and scientific use. Journal of Physical and Chemical Reference Data, 2002, 31(2): 387-535
[7]
Ji X, Yan J. Saturated thermodynamic properties for the air-water system at elevated temperatures and pressures. Chemical Engineering Science, 2003, 58(22): 5069-5077
[8]
Ji X, Yan J. Thermodynamic properties for humid gases from 298 to 573 K and up to 200 bar. Applied Thermal Engineering, 2006, 26(2-3): 251-258
[9]
Lemmon E W, Jacobsen R T, Penoncello S G, Friend D G. Thermodynamic properties of air and mixtures of nitrogen, argon, and oxygen from 60 to 2000 K at pressures to 2000 MPa. Journal of Physical and Chemical Reference Data, 2000, 29(3): 1-54
[10]
Cengel Y A, Boles M A. Thermodynamics: An Engineering Approach (5th edition). McGraw-Hill, 2005, 686-687
[11]
Wang Z, Chen H, Weng S. New calculation method for thermodynamic properties of humid air in humid air turbine cycle—general model and solutions for saturated humid air. Energy, 2013,in press)
CrossRef Google scholar
[12]
Wang Z, Chen H, Weng S. Revised Dalton’s method for calculation of thermodynamic properties of unsaturated humid air and gas mixture after combustion in humid air turbine cycle. Energy, 2013, in press)
CrossRef Google scholar

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