ISSN:
1745-6584
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Energy, Environment Protection, Nuclear Power Engineering
,
Geosciences
Notes:
The use of steady-state models can sometimes reduce the computational resources and input data required for solution of transient transport problems. A large column experiment was performed to test whether solute transport parameters determined from a steady flow experiment may be used in transient, unsaturated flow and transport model predictions. Tritiated water and bromide were applied at a steady rate to the top of a 0.95 m diameter by 6 m deep soil column containing unsaturated soil. After 10 days, tracers were eliminated from the irrigation water. When the soil moisture content within the column ceased to change, another 10-day pulse of tritiated water and bromide was applied, followed by water without tracers. Transport model parameters were determined through optimization, using breakthrough curves observed at various depths. The tritiated water and bromide pulses lagged behind the wetting front during infiltration into the relatively dry soil. The bromide pulse moved 17–20% faster than the tritiated water pulse, because of anion exclusion. Breakthrough curves for the transient and steady-state experiments were similar. Because the solute fronts lagged significantly behind the moisture fronts, steady-state transport parameters, when used in a fully transient numerical model, fairly described the transport under transient conditions.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1745-6584.1993.tb01811.x
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