Air-Water Interfacial Area and Capillary Pressure: Porous-Medium Texture Effects and an Empirical Function
Publication: Journal of Hydrologic Engineering
Volume 17, Issue 7
Abstract
The relationship between air-water interfacial area and capillary pressure under higher water-content conditions is investigated for four natural porous media. The results show that the magnitude of the air-water interfacial area increases with increasing capillary pressure, consistent with the decrease in water saturation. The maximum observed air-water interfacial areas are dependent upon the magnitude of residual water saturation, which itself is condition-dependent. The more well-sorted porous-medium exhibited a greater rate of change of air-water interfacial area with capillary pressure than the more poorly sorted porous media. The observed relationship between air-water interfacial area and capillary pressure was quantified by coupling an empirical equation describing the air-water interfacial area versus water saturation relationship with the van Genuchten equation relating water saturation and capillary pressure. This equation produced reasonable simulations of the measured data.
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Acknowledgments
This research was funded by the USDA National Research Initiative Program, with additional support from the NIEHS Superfund Research Program (#ES-4940) and EPA Science to Achieve Results Program. We also thank Sheri Musil, Dr. Art Warrick, Dr. Mike Yao, and Dr. Janick Artiola for their kind assistance and the reviewers for their constructive comments.
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Information & Authors
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Published In
Journal of Hydrologic Engineering
Volume 17 • Issue 7 • July 2012
Pages: 829 - 832
Copyright
© 2012. American Society of Civil Engineers.
History
Received: Dec 22, 2010
Accepted: Sep 26, 2011
Published online: Jun 15, 2012
Published in print: Jul 1, 2012
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