Publications associées à A method for assessing the feasibility of air-bubble screens to reduce morphological gradients in open-channel bends

Spatiotemporal Dynamics of Flow and Hydrochemistry in Drainage Networks

Despite their high ecological value, non-perennial streams have received less attention than their perennial counterparts. This doctoral thesis addresses this disparity by advancing knowledge on the dynamics of the drainage density and hydrologic processes ...

EPFL2024

Laterally unconfined neutral or negative buoyancy inflow into a quiescent ambient over sloping bottom

Haoran Shi

This work studies the nearshore hydrodynamics of a shallow turbulent flow entering a laterally unconfined quiescent ambient with a sloping bottom boundary. Examples of such flow are neutrally buoyant ebb tidal jets and hyperpycnal river plumes entering ope ...

EPFL2023

The biofilm ecology of proglacial floodplain streams

Jade Brandani

Glacial forelands figure among the most dynamic landscapes on Earth, and their formation is currently accelerating given glacier shrinkage. Draining these forelands are streams hosting unique microbial communities, which have the capacity to impact both th ...

EPFL2023

Clogging of riverbed substrates by fine sediment

Romain Maxime Dubuis

Riverbeds represent the habitat of numerous aquatic species. Exchanges between the groundwater, the hyporheic zone and the surface flow are also essential for river ecosystems. Fine sediment transported by rivers deposits inside or on top of the bed and mo ...

EPFL2023

Experimental Study on Bedload Transport and Bedforms: Behaviour and Interplay in Steep Turbulent Streams

Ivan Pascal

In mountain regions, steep streams play an important role in water and sediment connectivity. In these highly dynamic systems, water flow features, sediment fluxes and stream morphologies are tightly interlinked over a broad range of temporal and spatial s ...

EPFL2022

Assessing Subaquatic Mass Movement Hazards: an Integrated Observational and Hydrodynamic Modelling Approach

Alfred Johny Wüest, Damien Bouffard, Nathalie Dubois, Carl Love Mikael Råman Vinnå

High-resolution lake and reservoir bathymetric surveys can pinpoint locations that may experience underwater landslides (subaquatic sedimentary mass movements). These can pose a risk to underwater and shoreline infrastructure. This paper outlines an approa ...

2020

Morphology and morphodynamics of braided rivers: an experimental investigation

Daniel Vito Papa

Braided rivers form some of the most fascinating fluvial patterns found on Earth. They are identifiable by their unique morphology of complex networks of intertwined channels that spread across wide floodplains. Detailed knowledge of their dynamics is need ...

EPFL2020

Statistical and physical characterization of rainfall-driven overland flow morphologies

Mohsen Cheraghi

Environmental transport processes are highly coupled with the shape of landscapes. Modern catchment analysis with high-resolution data and huge computational powers demand more detailed within-cell metrics for surface evolution modeling. This dissertation ...

EPFL2019

Pioneer plant Phalaris arundinacea and earthworms promote initial soil structure formation despite strong alluvial dynamics in a semi-controlled field experiment

Claire Guenat, Pascal Turberg, Renée-Claire Le Bayon, Muhammad Riaz, Andreas Cedric Schomburg

Soil structure formation is among the most important processes in riverfloodplains which are strongly influ-enced by alluvial dynamics. In the context of river restoration projects, a better understanding of soil structureformation in habitats adjacent to ...

2019

Composition and superposition of alluvial deposits drive macro-biological soil engineering and organic matter dynamics in floodplains

Claire Guenat, Rodolphe Schlaepfer, Pascal Turberg, Renée-Claire Le Bayon, Andreas Cedric Schomburg

Soil structure formation in alluvial soils is a fundamental process in near-natural floodplains. A stable soil structure is essential for many ecosystem services and helps to prevent river bank erosion. Plants and earthworms are successful soil engineering ...

2019

Coherent Structure Interaction During Unsteady Separation

Karen Ann J Mulleners

Unsteady flow separation in rotationally augmented flow fields plays a significant role in the aerodynamic performance of industrial rotors, including wind turbines. Current computational models underestimate the aerodynamic loads due to the inaccurate pre ...

2019

Hydraulic-morphological habitat assessment in rivers considering residual flow, sediment replenishment and artificial flood events

Severin Stähly

Dams store water and trap sediment in their reservoirs. Downstream river segments, hence, are affected by a limited sediment dynamics. This becomes obvious by river bed incision, limited geomorphological variability and depletion of hydraulic habitats for ...

EPFL2019

Turbulent Flows over Rough Permeable Beds in Mountain Rivers: Experimental Insights and Modeling

Gauthier Paul Daniel Marie Rousseau

Steep mountain streams exhibit shallow waters with roughness elements such as stones and pebbles that are comparable in size to flow depth. Owing to the difficulty in measuring fluid velocities at the interface, i.e., from the rough permeable bed to the fr ...

EPFL2019

Catchment drainage network scaling laws found experimentally in overland flow morphologies

David Andrew Barry, Paolo Perona, Andrea Rinaldo, Mohsen Cheraghi

The scaling relation between the drainage area and stream length (Hack’s law), along with exceedance probabilities of drainage area, discharge and upstream flow network length are well known for channelized fluvial regions. We report here on a laboratory e ...

2018

Morphological resilience to flow fluctuations of fine sediment deposits in bank lateral cavities

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Carmelo Juez Jiménez, Matthias Thalmann

Lateral cavities are built in the banks of rivers for several purposes: to create harbors, to capture sed- iment, to keep a central navigable channel (i.e., Casiers de Girardon in the Rhone river) or to promote the formation of aquatic habitats if a limite ...

2018

Geomorphic work by gravity currents with varying initial conditions

Jessica Zordan

Gravity currents are density-driven flows that are able to transport high amounts of sediment and are responsible of great geomorphic changes. Moreover they can have severe repercussions on the environment since they are conveyors of substances, e.g. pollu ...

EPFL2018

Entrainment, transport and deposition of sediment by saline gravity currents

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Jessica Zordan, Carmelo Juez Jiménez

Few studies have addressed simultaneously the feedback between the hydrodynamics of a gravity cur- rent and the geomorphological changes of a mobile bed. Hydrodynamic quantities such as turbulent and mean velocities, bed shear stress and turbulent stresses ...

2018

The origin of fine sediment determines the observations of suspended sediment fluxes under unsteady flow conditions

Mário Jorge Rodrigues Pereira Da Franca, Carmelo Juez Jiménez

Field observations in a wide range of environments have shown that sediment availability is a major control on the suspended sediment observations in streams. Here we examine, via laboratory experiments, how the amount of proximal in-channel fine sediment ...

American Geophysical Union2018

Strategies for faster impregnation in melt thermoplastic resin transfer molding process

Damiano Salvatori

Continuous fiber thermoplastic composites are potential substitutes of steel in structural automotive components, since they combine fiber strength and rigidity with ductility, potential recyclability and low density of the thermoplastic (TP) matrix. Resin ...

EPFL2018

Hydromorphodynamic effects of the width ratio and local tributary widening on discordant confluences

António Heleno Cardoso, Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Sebastián Guillén Ludeña

River training works performed in the last couple of centuries constrained the natural dynamics of channel networks in locations that include the confluences between tributaries and main channels. As a result, the dynamics of these confluences are currentl ...

Gfg2017