Author(s): Roland Finance; Sebastien Proust; Celine Berni; Benoit Camenen; Louis Gostiaux
Linked Author(s): Sébastien Proust, Celine Berni, Benoît Camenen
Keywords: Open-channel flows; Shallow mixing layer; Suspended sediments
Abstract: Major exchanges of matter (sediments, nutrients, pollutants, etc.) can take place at river confluences, where variations in the velocity shear or density difference between the two tributaries can lead to dramatic changes in their mixing patterns (Sukhodolov et al., 2023). We report on an ongoing experimental study linking the presence or the absence of the different flow structures developing downstream of a confluence (Proust et al., 2022) with the mixing patterns and the mixing efficiency of suspended sediments. Starting from well-described sediment-free flow configurations (Cerino et al., 2024), one of the two incoming streams is supplied with suspended sediments, and we investigate: (i) the mixing patterns downstream of the confluence, using the concentration of suspended sediment as a tracer for the mixing; (ii) the feedback effects of the suspended sediments and of the mixing on the development of the different flow structures.
Year: 2025