[期刊论文]


Analytical solution and analysis for solute transport in streams with diffusive transfer in the hyporheic zone

作   者:
Akhilesh Kumar;D.C. Dalal;

出版年:2014

页     码:62 - 73
出版社:Elsevier BV


摘   要:

Solute transport in streams with diffusive transfer in the hyporheic zone is studied. Analytical solution of the diffusive transfer model is obtained by means of Laplace transform. Solutions are derived for a general situation, in which the concentration at the injection point is a function of time. In order to illustrate the use of present analytical solution, physical transport parameters are estimated for the observed data of Uvas Creek tracer experiment for chloride concentration and also of Wkra river tracer experiment. The concentration-time breakthrough curves obtained from the analytical solutions are found to be in good agreement with the observed as well as numerical concentration-time breakthrough curve. Step concentration-time profile and continuous concentration-time profile are considered as upstream boundary conditions for conservative solute. An instantaneous injection of solute is taken as an upstream boundary condition for reactive solute. It is noticed that with the increase in the value of porosity, the solute concentration in the main channel decreases. With the decrease in the value of Peclet number in the hyporheic zone, the overall solute concentration in the main channel decreases. Due to increase in the value of the sorption rate coefficient in the hyporheic zone, solute particles once enter into the hyporheic zone, reside for a longer time in the hyporheic zone. A sensitivity analysis is performed in order to identify the critical parameters for conservative as well as for reactive solute. It is found that the ratio of cross-sectional areas is much more sensitive compared to the other parameters for conservative solute. The Damkohler number in the hyporheic zone is the most sensitive parameter among all the parameters for reactive solute. The above observations indicate that the analytical solution can be reliably applied for the analysis of tracer experiments.



关键字:

Analytical techniques ; Hyporheic zone ; Surface/subsurface water interactions ; Transient storage ; Transport model ; Concentration


所属期刊
Journal of Hydro-environment Research
ISSN: 1570-6443
来自:Elsevier BV