Publications associées à Coastal morphodynamics

Stochastic Simulations and Machine Learning Modeling to Predict Bedload Transport and Bed Topography

In computational hydraulics models, predicting bed topography and bedload transport with sufficient accuracy remains a significant challenge. An accurate assessment of a river's sediment transport rate necessitates a prior understanding of its bed topograp ...

EPFL2024

Simulation of fine sediment deposition on floodplains

Giovanni De Cesare, Carmelo Juez Jiménez

Rivers extend beyond the channels that are typically associated with this word. Of particular interest are flood plains, where important hydro- and morphodynamic processes occur as a result of recurrent flooding. Ecologically, they also support the establi ...

2023

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

Floodplain Land Cover and Flow Hydrodynamic Control of Overbank Sedimentation in Compound Channel Flows

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Carmelo Juez Jiménez, Hannes Jenny

Overbank sedimentation is predominantly due to fine sediments transported under suspension that become trapped and settle in floodplains when high-flow conditions occur in rivers. In a compound channel, the processes of exchanging water and fine sediments ...

2019

Hydrodynamics of mountain-river confluences and its relationship to sediment transport

Mário Jorge Rodrigues Pereira Da Franca, Sebastián Guillén Ludeña

Mountain confluences are characterized by narrow and steep tributaries that provide important sediment load to the confluence, whereas themain channel supplies the dominant flow discharge. This results in a marked bed discordance between the tributary and ...

American Geophysical Union2017

EFFECT OF THE BED LOAD GRADATION ON THE MORPHODYNAMICS OF DISCORDANT CONFLUENCES

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

Within the fluvial network, river confluences are particular areas characterized by complex hydrodynamic, morphodynamic and sedimentary processes. These processes have been observed to be governed by parameters such as the discharge ratio, the junction ang ...

2017

Assessing the Hydro-Morphodynamic Response of a Beach Protected by Detached, Impermeable, Submerged Breakwaters: A Numerical Approach

Coastal areas host a large fraction of the world's population and are exposed to natural extreme events, which are a serious threat to human life, as well as to economies. For this reason, sea storms are increasingly the object of studies, and the design o ...

Coastal Education & Research Foundation2016

Impacts of wave and tidal forcing on 3D nearshore processes on natural beaches. Part I: Flow and turbulence fields

David Andrew Barry, Roham Bakhtyar

The major objective of this study was to develop further understanding of 3D nearshore hydrodynamics under a variety of wave and tidal forcing conditions. The main tool used was a comprehensive 3D numerical model – combining the flow module of Delft3D with ...

Techno-Press2016

Impacts of wave and tidal forcing on 3D nearshore processes on natural beaches. Part II. Sediment transport

David Andrew Barry, Roham Bakhtyar

This is the second of two papers on the 3D numerical modeling of nearshore hydro- and morphodynamics. In Part I, the focus was on surf and swash zone hydrodynamics in the cross-shore and longshore directions. Here, we consider nearshore processes with an e ...

Techno-Press2016

Morphodynamics in river confluences

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

Within the fluvial network, confluences are considered particular areas in what concerns ecological connectivity, flood safety and water quality. These characteristics were degraded in many cases, by previous channelization works, which resulted in rivers ...

2015

Hydro‐morphodynamic evolution in a 90° movable bed discordant confluence with low discharge ratio

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

Confluences with low discharge and momentum ratios, where narrow steep tributaries with high sediment load join a wide low-gradient main channel that provides the main discharge, are often observed in high mountain regions such as in the upper- Rhone river ...

Wiley-Blackwell2015

Ecomorphodynamic approaches to river anabranching patterns

Paolo Perona, Benoît Crouzy

We investigate the influence of vegetation on river morphological instabilities using an analytical framework. We first discuss the important role of the hydrological (flooding frequency) and biological (vegetation development rate) timescales. As long as ...

Elsevier2016

Coherent structures in open channel flows with bed load transport over an hydraulically rough bed

Mário Jorge Rodrigues Pereira Da Franca

Excess sediment production in the upper parts of catchments may result in important impacts over morphodynamics of gravel bed-rivers. By changing morphodynamics, sediment overfeeding may induce important changes in the structure of near-bed flow, mainly in ...

CRC Press/Balkema2014

Bulk velocity measurements by video analysis of dye tracer in a macro-rough channel

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Tamara Ghilardi

Steep mountain rivers have hydraulic and morphodynamic characteristics that hinder velocity measurements. The high spatial variability of hydraulic parameters, such as water depth (WD), river width and flow velocity, makes the choice of a representative cr ...

Institute of Physics2014

Morphodynamic differences induced by different confluence angles in widen confluences

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

River widening is commonly used as a solution for the rehabilitation of rivers with the main purposes of allowing the river to adjust to its natural dynamics and to improve riparian and instream habitat for flora and fauna, by increasing the heterogeneity ...

CRC Press/Balkema2014

Influencing Flow Patterns and Bed Morphology in Open Channels and Rivers by Means of an Air-Bubble Screen

Anton Schleiss, Koen Blanckaert, Violaine Dugué

The ability of a bubble screen to redistribute the flow field and bed morphology in shallow rivers and open channels has been investigated in laboratory experiments. Rising air bubbles generated by a pressurized porous tube situated on the bed induced seco ...

American Society of Civil Engineers2014

Two-phase flow modeling of the influence of wave shapes and bed slope on nearshore hydrodynamics

David Andrew Barry, Roham Bakhtyar, Amir Mehdi Razmi

An Eulerian two-phase flow model (air-water) was used to simulate nearshore hydrodynamic processes driven by wave motion. The flow field was computed with the Reynolds-Averaged Navier-Stokes equations in conjunction with the Volume-Of-Fluid method and the ...

Coastal Education and Research Foundation2013

Numerical experiments on interactions between wave motion and variable-density coastal aquifers

David Andrew Barry, Alessandro Brovelli, Roham Bakhtyar

A comprehensive two-dimensional (cross-shore) process-based numerical model of nearshore hydrodynamics (based on the Navier-Stokes equations, k-ε turbulence closure and the Volume-Of-Fluid method), beach morphology, and variable-density groundwater flow (S ...

Elsevier2012

Numerical experiments on breaking waves on contrasting beaches using a two-phase flow approach

David Andrew Barry, Roham Bakhtyar

A mechanistic understanding of beach environments needs to account for interactions of oceanic forcing and beach materials, in particular the role of waves on the evolution of the beach profile. A fully coupled two-phase flow model was used to simulate nea ...

Elsevier2012

Numerical experiments of breaking waves on dissipative and intermediate beaches using a two-phase flow method

David Andrew Barry, Roham Bakhtyar

A fully coupled two-phase flow model was developed to simulate nearshore fluid-sediment turbulent flow. It includes the Reynolds-Averaged Navier-Stokes equations and turbu¬lent stress closures for each phase, and accounts for inter-granular stresses. It wa ...

2011