Correspondence of the Gardner and van Genuchten/Mualem relativepermeability function parameters
Abstract
The Gardner and van Genuchten models of relativepermeability are widely used in analytical and numerical solutions toflow problems. However, the applicab ility of the Gardner model to realproblems is usually limited, because empirical relative permeability datato calibrate the model are not routinely available. In contrast, vanGenuchten parameters can be estimated using more routinely availablematric potential and saturation data. However, the van Genuchten model isnot amenable to analytical solutions. In this paper, we introducegeneralized conversion formulae that reconcile these two models. Ingeneral, we find that the Gardner parameter alpha G is related to the vanGenuchten parameters alpha vG and n by alpha G=alpha vG ~; 1:3 n. Thisconversion rule will allow direct recasting of Gardner-based analyticalsolutions in the van Genuchten parameter space. The validity of theproposed formulae was tested by comparing the predicted relativepermeability of various porous media with measured values.
- Authors:
- Publication Date:
- Research Org.:
- Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
- Sponsoring Org.:
- USDOE. Office of Civilian Radioactive Waste Management.Waste Management System
- OSTI Identifier:
- 927378
- Report Number(s):
- LBNL-62433
Journal ID: ISSN 0043-1397; WRERAQ; R&D Project: G60651; BnR: DF0961000; TRN: US200811%%127
- DOE Contract Number:
- DE-AC02-05CH11231
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Water Resources Research; Journal Volume: 43; Related Information: Journal Publication Date: 2007
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 54; ANALYTICAL SOLUTION; DATA; NUMERICAL SOLUTION; PERMEABILITY; SATURATION
Citation Formats
Ghezzehei, Teamrat A., Kneafsey, Timothy J., and Su, Grace W. Correspondence of the Gardner and van Genuchten/Mualem relativepermeability function parameters. United States: N. p., 2007.
Web. doi:10.1029/2006WR005339.
Ghezzehei, Teamrat A., Kneafsey, Timothy J., & Su, Grace W. Correspondence of the Gardner and van Genuchten/Mualem relativepermeability function parameters. United States. doi:10.1029/2006WR005339.
Ghezzehei, Teamrat A., Kneafsey, Timothy J., and Su, Grace W. Wed .
"Correspondence of the Gardner and van Genuchten/Mualem relativepermeability function parameters". United States.
doi:10.1029/2006WR005339. https://www.osti.gov/servlets/purl/927378.
@article{osti_927378,
title = {Correspondence of the Gardner and van Genuchten/Mualem relativepermeability function parameters},
author = {Ghezzehei, Teamrat A. and Kneafsey, Timothy J. and Su, Grace W.},
abstractNote = {The Gardner and van Genuchten models of relativepermeability are widely used in analytical and numerical solutions toflow problems. However, the applicab ility of the Gardner model to realproblems is usually limited, because empirical relative permeability datato calibrate the model are not routinely available. In contrast, vanGenuchten parameters can be estimated using more routinely availablematric potential and saturation data. However, the van Genuchten model isnot amenable to analytical solutions. In this paper, we introducegeneralized conversion formulae that reconcile these two models. Ingeneral, we find that the Gardner parameter alpha G is related to the vanGenuchten parameters alpha vG and n by alpha G=alpha vG ~; 1:3 n. Thisconversion rule will allow direct recasting of Gardner-based analyticalsolutions in the van Genuchten parameter space. The validity of theproposed formulae was tested by comparing the predicted relativepermeability of various porous media with measured values.},
doi = {10.1029/2006WR005339},
journal = {Water Resources Research},
number = ,
volume = 43,
place = {United States},
year = {Wed Jan 03 00:00:00 EST 2007},
month = {Wed Jan 03 00:00:00 EST 2007}
}
-
The Gardner and van Genuchten models of relativepermeability are widely used in analytical and numerical solutions toflow problems. However, the applicability of the Gardner model to realproblems is usually limited, because empirical relative permeability datato calibrate the model are not routinely available. In contrast, vanGenuchten parameters can be estimated using more routinely availablematric potential and saturation data. However, the van Genuchten model isnot amenable to analytical solutions. In this paper, we introducegeneralized conversion formulae that reconcile these two models. Ingeneral, we find that the Gardner parameter alpha G is related to the vanGenuchten parameters alpha vG and n by alphamore »
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A non-iterative scheme for orthogonal grid generation with control function and specified boundary correspondence on three sides
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