Articles | Volume 14, issue 2
https://doi.org/10.5194/esurf-14-269-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/esurf-14-269-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Experimental study of time-averaged flow and turbulence over asymmetric tidal dunes
Kevin Bobiles
CORRESPONDING AUTHOR
MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
Faculty of Geosciences, University of Bremen, Bremen, Germany
Bernhard Kondziella
Federal Waterways Engineering and Research Institute (BAW), Hamburg, Germany
Christina Carstensen
Federal Waterways Engineering and Research Institute (BAW), Hamburg, Germany
present address: Federal Waterways and Shipping Administration (WSV), Kiel, Germany
Elda Miramontes
MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
Faculty of Geosciences, University of Bremen, Bremen, Germany
Ingrid Holzwarth
Federal Waterways Engineering and Research Institute (BAW), Hamburg, Germany
Alice Lefebvre
MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
Related authors
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Alice Lefebvre and Julia Cisneros
Earth Surf. Dynam., 11, 575–591, https://doi.org/10.5194/esurf-11-575-2023, https://doi.org/10.5194/esurf-11-575-2023, 2023
Short summary
Short summary
Underwater dunes are found in various environments with strong hydrodynamics and sandy sediment. Using a numerical model, we investigated how the dune shape influences flow velocity and turbulence. We propose a classification with three types of dunes, depending on their mean lee side angles (low-angle dunes, intermediate-angle dunes and high-angle dunes). We discuss the implications of this classification on the interaction between dune morphology, flow and sediment transport.
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Short summary
This study examines how the shape of tidal dunes influences flow and turbulence under reversing currents, simulating tidal conditions in a large flume. We show that dune slope properties significantly affect flow patterns, especially the presence and size of intermittent or permanent flow separation and turbulent wake. The results highlight the key role of dune morphology in shaping flow dynamics, with implications for sediment transport and coastal morphodynamics.
This study examines how the shape of tidal dunes influences flow and turbulence under reversing...