Abstract
In this study, non-equilibrium transport of suspended sediment from one equilibrium state to another is investigated. Based on a convective-diffusion equation, a numerical model for flow with suspended sediment is developed by considering the effect of concentration-dependent settling velocity. The numerical model is validated by comparing analytical solutions and experimental results. The concentration profiles, mean concentrations and distance necessary to reach a new equilibrium state are examined by comparing them with the results of constant settling velocity. For a high concentration flow, the results indicate that evident differences between the above three indicators can be determined with and without concentration-dependent settling velocity. Additionally, the effects of concentration-dependent settling velocity are sensitive to the sediment mobility parameter (or Rouse number), although they are nearly independent of the diffusion Reynolds number.
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Acknowledgements
The study is financially supported by National Key R&D Program of China (2017YFC0504704) and Natural Science Foundation of Education Department of Shaanxi Province, China (no. 16KJ1543).
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Jing, H., Chen, G., Wang, W. et al. Effects of concentration-dependent settling velocity on non-equilibrium transport of suspended sediment. Environ Earth Sci 77, 549 (2018). https://doi.org/10.1007/s12665-018-7731-9
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DOI: https://doi.org/10.1007/s12665-018-7731-9