Home

Person

Christophe Ancey

About
Privacy
Disclaimer

Graph Chatbot

Related publications (96)

Particle diffusion in non-equilibrium bedload transport simulations

This paper examines the importance of particle diffusion relative to advection in bed load transport. Particle diffusion is not included in existing approaches to bedload transport. Based on recent advances in the probabilistic theory of sediment transport ...

Elsevier Science Inc2016

Continuous monitoring of bedload transport in a laboratory flume using an impact sensor

Christophe Ancey, Blaise Etienne Marceau Dhont, Gauthier Paul Daniel Marie Rousseau

Bedload transport rate in gravel-bed rivers shows large non-Gaussian fluctuations, even under steady flow conditions. The development of high-resolution measurement techniques during the last two decades creates research opportunities to study the intermit ...

American Society of Civil Engineers2016

Asymmetric breaking size-segregation waves in dense granular free-surface flows

Christophe Ancey, Kasper van der Vaart

Debris and pyroclastic flows often have bouldery flow fronts, which act as a natural dam resisting further advance. Counter intuitively, these resistive fronts can lead to enhanced run-out, because they can be shouldered aside to form static levees that se ...

Cambridge University Press2016

Entrainment,motion, and deposition of coarse particles transported by water over a sloping mobile bed

Christophe Ancey, Joris Heyman

In gravel bed rivers, bed load transport exhibits considerable variability in time and space. Recently, stochastic bed load transport theories have been developed to address the mechanisms and effects of bed load transport fluctuations. Stochastic models i ...

Wiley-Blackwell2016

Particle-size and -density segregation in granular free-surface flows

Christophe Ancey

When a mixture of particles, which differ in both their size and their density, avalanches downslope, the grains can either segregate into layers or remain mixed, dependent on the balance between particle-size and particle-density segregation. In this pape ...

Cambridge University Press2015

Stochastic interpretation of the advection diffusion equation and its relevance to bed load transport

Christophe Ancey, Joris Heyman

The advection diffusion equation is one of the most widespread equations in physics. It arises quite often in the context of sediment transport, e.g., for describing time and space variations in the particle activity (the solid volume of particles in motio ...

American Geophysical Union2015

Dynamics of glide avalanches and snow gliding

Christophe Ancey

In recent years, due to warmer snow cover, there has been a significant increase in the number of cases of damage caused by gliding snowpacks and glide avalanches. On most occasions, these have been full-depth, wet-snow avalanches, and this led some people ...

Amer Geophysical Union2015

An Underlying Asymmetry within Particle-size Segregation

Nicolas Andreini, Christophe Ancey, Gaël Epely Chauvin, Kasper van der Vaart

We experimentally study particle scale dynamics during segregation of a bidisperse mixture under oscillatory shear. Large and small particles display an underlying asymmetry that is dependent on the local particle concentration, with small particles segreg ...

American Physical Society2015

Spatial correlations in bed load transport: Evidence, importance, and modeling

Christophe Ancey, François Mettra, Joris Heyman, Hongbo Ma

This article examines the spatial {dynamics of bed load particles} in water. We focus particularly on the fluctuations of particle activity, which is defined as the number of moving particles per unit bed {length}. Based on a stochastic model recently prop ...

Amer Geophysical Union2014

A microstructural approach to bed load transport: mean behaviour and fluctuations of particle transport rates

Christophe Ancey, Joris Heyman

This paper concerns a model of bed load transport, which describes the advection and dispersion of coarse particles carried by a turbulent water stream. The challenge is to develop a microstructural approach that, on the one hand, yields a parsimonious des ...

Cambridge University Press2014

Visualization of the internal flow properties and the material exchange interface in an entraining viscous Newtonian gravity current

Christophe Ancey, Belinda Margaret Bates

In order to simulate a simple entraining geophysical flow, a viscous Newtonian gravity current is released from a reservoir by a dam-break and flows along a rigid horizontal bed until it meets a layer of entrainable material of finite depth, identical to t ...

Springer Verlag2014

Statistics of bedload transport over steep slopes: Separation of time scales and collective motion

Christophe Ancey, François Mettra, Joris Heyman, Hongbo Ma

Steep slope streams show large fluctuations of sediment discharge across several time scales. These fluctuations may be inherent to the internal dynamics of the sediment transport process. A probabilistic framework thus seems appropriate to analyze such a ...

American Geophysical Union2013

Granular suspension avalanches. II. Plastic regime

Nicolas Andreini, Christophe Ancey, Gaël Epely Chauvin

We present flume experiments showing plastic behavior for perfectly density-matched suspensions of non-Brownian particles within a Newtonian fluid. In contrast with most earlier experimental investigations (carried out using coaxial cylinder rheometers), w ...

Amer Inst Physics2013

Granular suspension avalanches. I. Macro-viscous behavior

Nicolas Andreini, Christophe Ancey, Gaël Epely Chauvin

We experimentally studied the flow behavior of a fixed volume of granular suspension, initially contained in a reservoir and released down an inclined flume. Here “granular suspension” refers to a suspension of non-Brownian particles in a viscous fluid. De ...

Amer Inst Physics2013

The dam-break problem for concentrated suspensions of neutrally buoyant particles

Nicolas Andreini, Christophe Ancey, Gaël Epely Chauvin

This paper addresses the dam-break problem for particle suspensions, that is, the flow of a finite volume of suspension released suddenly down an inclined flume. We were concerned with concentrated suspensions made up of neutrally-buoyant non-colloidal par ...

Cambridge University Press2013

Viscoplastic dambreak waves: review of simple computational approaches and comparison with experiments

Nicolas Andreini, Christophe Ancey, Gaël Epely Chauvin

We investigated the dam-break problem for Herschel-Bulkley fluids: a fixed volume of a viscoplastic material (a polymeric gel called Carbopol ultrez 10) was released and flowed down an inclined flume. Using Particle Image Velocimetry techniques, we measure ...

Elsevier2012

Internal dynamics of Newtonian and viscoplastic fluid avalanches down a sloping bed

Nicolas Andreini, Christophe Ancey, Gaël Epely Chauvin

We experimentally investigated the spreading of fluid avalanches (i.e., fixed volumes of fluid) down an inclined flume. Emphasis was given to the velocity field within the head. Using specific imaging techniques, we were able to measure velocity profiles w ...

2012

Multi-component particle size segregation in shallow granular avalanches

Christophe Ancey

A general continuum theory for particle size segregation and diffusive remixing in polydisperse granular avalanches is formulated using mixture theory. Comparisons are drawn to existing segregation theories for bi-disperse mixtures and the case of a ternar ...

Cambridge University Press2011

Refractive-index and density matching in concentrated particle suspensions: a review

Sébastien Wiederseiner, Nicolas Andreini, Christophe Ancey, Gaël Epely Chauvin

Optical measurement techniques such as particle image velocimetry (PIV) and laser Doppler velocimetry (LDV) are now routinely used in experimental fluid mechanics to investigate pure fluids or dilute suspensions. For highly concentrated particle suspension ...

Springer-Verlag2011

Experimental investigation into segregating granular flows down chutes

Sébastien Wiederseiner, Nicolas Andreini, Christophe Ancey, Gaudenz Moser, Gaël Epely Chauvin

We experimentally investigated how a binary granular mixture made up of spherical glass beads size ratio of 2 behaved when flowing down a chute. Initially, the mixture was normally graded, with all the small particles on top of the coarse grains. Segregati ...

2011

Page 3 of 5