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Read Full Article (file size: 663560 bytes) Cited by
WATER RESOURCES RESEARCH,
VOL. 41,
W04015,
doi:10.1029/2004WR003379,
2005
Estimating soil hydraulic parameters from transient flow experiments in a centrifuge using parameter optimization technique
Jirka Šimůnek
Department of Environmental Sciences, University of California, Riverside, California, USA
John R. Nimmo
U.S. Geological Survey, Menlo Park, California, USA
Abstract
A modified version of the Hydrus software package that can directly or inversely simulate water flow in a transient centrifugal
field is presented. The inverse solver for parameter estimation of the soil hydraulic parameters is then applied to multirotation
transient flow experiments in a centrifuge. Using time-variable water contents measured at a sequence of several rotation
speeds, soil hydraulic properties were successfully estimated by numerical inversion of transient experiments. The inverse
method was then evaluated by comparing estimated soil hydraulic properties with those determined independently using an equilibrium
analysis. The optimized soil hydraulic properties compared well with those determined using equilibrium analysis and steady
state experiment. Multirotation experiments in a centrifuge not only offer significant time savings by accelerating time but
also provide significantly more information for the parameter estimation procedure compared to multistep outflow experiments
in a gravitational field.
Received 28
May
2004;
accepted 7
February
2005;
published 27
April
2005.
Keywords: centrifuge;
Hydrus-1D;
soil hydraulic properties;
parameter estimation.
Index Terms: 1847 Hydrology: Modeling; 1849 Hydrology: Numerical approximations and analysis; 1894 Hydrology: Instruments and techniques: modeling; 1875 Hydrology: Vadose zone; 1866 Hydrology: Soil moisture.
Read Full Article (file size: 663560 bytes) Cited by
Citation: Šimůnek, J., and J. R. Nimmo
(2005),
Estimating soil hydraulic parameters from transient flow experiments in a centrifuge using parameter optimization technique,
Water Resour. Res.,
41,
W04015,
doi:10.1029/2004WR003379.
Copyright 2005 by the American Geophysical Union.
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