Persistence of Skewness in Longitudinal Dispersion Data: Can the Dead Zone Model Explain It After All?
Publication: Journal of Hydraulic Engineering
Volume 128, Issue 9
Abstract
Field studies reporting coefficients of temporal skewness that do not decrease in the main flow direction have cast doubt on the transient storage (TS) or dead zone model of longitudinal dispersion in rivers and streams. In this study, the conditions under which the TS model predicts persistent or growing skewness coefficients are investigated. The findings clearly show that, though not outright impossible, an instantaneous slug release into a uniform channel reach is, indeed, extremely unlikely to result in persistent or growing skewness coefficients. In contrast, the passage of a tracer or pollutant along a sequence of (hydraulically) different subreaches may easily give rise to nondecaying skewness coefficients, the occurrence of which is governed by the parameter sets of the subreaches concerned. Thus, the TS model does show a certain potential to explain the persistence of skewness. The findings reported here are expected to be useful in guiding future field studies on the subject. An application of the newly derived criterion to stream tracer data has been successful.
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References
Bencala, K. E., and Walters, R. A.(1983). “Simulation of solute transport in a mountain pool-and-riffle stream: a transient storage model.” Water Resour. Res., 19(3), 718–724.
Czernuszenko, W., and Rowinski, P. M.(1997). “Properties of the dead-zone model of longitudinal dispersion in rivers.” J. Hydraul. Res., 35(4), 491–504.
Czernuszenko, W., Rowinski, P. M., and Sukhodolov, A.(1998). “Experimental and numerical validation of the dead-zone model for longitudinal dispersion in rivers.” J. Hydraul. Res., 36(2), 269–280.
Hays, J. R., Krenkel, P. A., and Schnelle, K. B. (1966). “Mass transport mechanisms in open-channel flow.” Tech. Rep. No. 8, Vanderbuilt Univ., Nashville, Tenn.
Hunt, B.(1999). “Dispersion model for mountain streams.” J. Hydraul. Eng., 125(2), 99–105.
Nordin, C. F., and Troutman, B. M.(1980). “Longitudinal dispersion in rivers: The persistence of skewness in observed data.” Water Resour. Res., 16(1), 123–128.
Schmid, B. H.(1995). “On the transient storage equations for longitudinal solute transport in open channels: Temporal moments accounting for the effects of first-order decay.” J. Hydraul. Res., 33(5), 595–610.
Schmid, B. H. (1997). “Analytic solution of the transient storage equations accounting for solute decay.” Environmental and Coastal Hydraulics: Protecting the Aquatic Habitat, Proc., 27th IAHR Congress, San Francisco, Theme B, Vol. 1, 15–20.
Seo, I. W., and Cheong, T. S.(2001). “Moment-based calculation of parameters for the storage zone model for river dispersion.” J. Hydraul. Eng., 127(6), 453–465.
Wörman, A.(2000). “Comparison of models for transient storage of solutes in small streams.” Water Resour. Res., 36(2), 455–468.
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Copyright © 2002 American Society of Civil Engineers.
History
Received: Jul 24, 2000
Accepted: Mar 20, 2002
Published online: Aug 15, 2002
Published in print: Sep 2002
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