Influence of ambient flow on the behavior of dense effluent discharged into the water environment

Document Type : Research Article

Authors

Faculty of Civil and Environmental Engineering, Amir Kabir University of Technology, Tehran, Iran.

Abstract

Due to the limitation of natural freshwater resources and population growth in recent decades, human has turned to the development of water desalination plants to fill the gap between supply and demand. The most important environmental problem of desalination plants is the production of brine (containing a high concentration of salt) that is discharged directly into the sea. Various factors affect the dilution rate of discharged effluent, one of the most important of which is the ambient flow. In this study, using CorJet integral model, the effect of ambient flow velocity on the characteristics of jets and plumes and their dilution rates are investigated. The direction and magnitude of the ambient flow affect the mixing of the discharged effluent. This effect is the greatest when the ambient flow velocity is higher than the discharged effluent velocity. In this case, the effluent is completely diverted from its original path and advected in the direction of the ambient flow. In the presence of ambient flow, the greater the discharge angle relative to the horizon, the greater the effluent trajectory length and dilution rate. Furthermore, the discharge angle of 90° results in the highest dilution rate of effluents when the ambient flow is present. When the angle between the effluent discharge and the ambient flow (0 <ϕ <180) increases, the jet trajectory length, the horizontal distance from the discharge point to where the effluent impacts the ground, and the effluent dilution rate decrease.

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Main Subjects

References

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Amirkabir Journal of Civil Engineering
Volume 53, Issue 9
December 2021
Pages 4081-4102

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