Publications associées à Unified macro-to-microscale method to predict two-phase frictional pressure drops of annular flows

Measurement and modelling of dynamic fluid saturation in carbon reinforcements

Véronique Michaud, Baris Çaglar, Helena Luisa Teixido Pedarros, Guillaume Clément Broggi

We propose a methodology to monitor the progressive saturation of a non-translucent unidirectional carbon fabric stack through its thickness by means of X-ray radiography and extract the dynamic saturation curves using image analysis. Four constant flow ra ...

2023

A unified framework for Simplicial Kuramoto models

Alexis Arnaudon

Simplicial Kuramoto models have emerged as a diverse and intriguing class of models describing oscillators on simplices rather than nodes. In this paper, we present a unified framework to describe different variants of these models, categorized into three ...

2024

Effects of velocity-dependent apparent toughness on the pre- and post-shut-in growth of a hydraulic fracture

Dong Liu, Guanyi Lu

We investigate the growth of a plane-strain/radial hydraulic fracture in an infinite impermeable medium driven by a constant injection rate assuming that the apparent toughness scales with the decreasing fracture growth rate in a power-law relation. The vi ...

ELSEVIER SCI LTD2022

Quantifying the transition of impact mechanisms of geophysical flows against flexible barrier

Xingyue Li

Flexible barriers have been increasingly used worldwide for mitigating natural hazards involving various geophysical flows. The analysis and design of flexible barriers need to distinguish two major impact mechanisms, runup and pile-up, which remain poorly ...

ELSEVIER2021

Dynamic response of a compressible binary fluid mixture

Ignacio Pagonabarraga Mora

Binary fluids are present in a wide variety of systems at microscales, such as microfluidic devices containing drops, fluids with air bubbles trapped in them, and devices designed to mix fluids or to make two fluid substances react. Microfluidics devices a ...

2020

Comparison of Reduced-Basis techniques for the model order reduction of parametric incompressible fluid flows

Carlo Fiorina

The applicability of two Reduced-Basis techniques to parametric laminar and turbulent incompressible fluid flow problems in nuclear engineering is studied in this work. The Reduced-Basis methods are used to generate Reduced-Order Models (ROMs) that can acc ...

PERGAMON-ELSEVIER SCIENCE LTD2020

On Von Karman Modeling For Turbulent Flow Near A Wall

Jacques Rappaz, Jonathan Rochat

Mixing-length models are often used by engineers in order to take into account turbulence phenomena in a flow. This kind of model is obtained by adding a turbulent viscosity to the laminar one in Navier-Stokes equations. When the flow is confined between t ...

2019

GPU-accelerated Pelton turbine simulation using finite volume particle method coupled with linear eddy viscosity models

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens, Takashi Kumashiro

The numerical investigation of the unsteady flow patterns around a Pelton bucket can be helpful to improve the overall turbine efficiency by optimizing the bucket design based on identified loss mechanisms. Since the flow is highly turbulent, modeling the ...

IOP PUBLISHING LTD2019

Numerical Modelling of Two-Phase Flow with Moving Boundary Fitted Meshes

Erik Gros

In this thesis, a computational approach is used to study two-phase flow including phase change by direct numerical simulation. This approach follows the interface with an adaptive moving mesh. The incompressible Navier-Stokes equations are solved, in tw ...

EPFL2018

Moving mesh method for direct numerical simulation of two-phase flow with phase change

John Richard Thome, Gustavo Rabello Dos Anjos, Erik Gros

A moving mesh approach is employed to simulate two-phase flow with phase change. The mathematical model is based on the Arbitrary Lagrangian-Eulerian (ALE) description of the axisymmetric Navier-Stokes equations and energy conservation. These equations are ...

ELSEVIER SCIENCE INC2018

Numerical simulation of mechanical deformation of semi-solid material using a level-set based finite element method

Roland Logé

In this work, a level-set based finite element method was used to numerically evaluate the mechanical behavior in a small deformation range of semi-solid materials with different microstructure configurations. For this purpose, a finite element model of th ...

Institute of Physics2017

Propagation of a height contained hydraulic fracture in turbulent flow regimes

Brice Tanguy Alphonse Lecampion, Haseeb Zia

We investigate theoretically and numerically the impact of the transition from laminar to turbulent flow on the propagation of a height contained hydraulic fracture (i.e. PKN geometry). We account for the inertial terms in the balance of momentum and expre ...

Pergamon-Elsevier Science Ltd2017

A comparative study of shock capturing models for the discontinuous Galerkin method

Jan Sickmann Hesthaven

Dealing with strong shocks while retaining numerical dissipation of reasonably low level has been one of the major challenges for high order methods like discontinuous Galerkin. In the literature, various shock capturing models have been designed based on ...

Elsevier2017

From rock to magma and back again: The evolution of temperature and deformation mechanism in conduit margin zones

Marie Estelle Solange Violay, Michael Heap

Explosive silicic volcanism is driven by gas overpressure in systems that are inefficient at outgassing. The zone at the margin of a volcanic conduit-thought to play an important role in the outgassing of magma and therefore pore pressure changes and explo ...

Elsevier2017

Resonance in swirling wakes and sloshing waves : non-normal and sublinear effects

Francesco Viola

Similarly to mechanical structures, stable flows can exhibit resonance when perturbed by an impulsive or harmonic forcing. Swirling wakes and sloshing waves belong to this kind of flows and manifest large energy response when excited close to their natural ...

EPFL2016

Two-Phase Heat Transfer Mechanisms within Plate Heat Exchangers : Experiments, Modeling and Simulations

Raffaele Luca Amalfi

Plate heat exchangers are adopted in many domestic and industrial applications, such as ventilation, air conditioning, evaporation or condensation process, heat pumps and cooling of hydrodynamic circuits in engines. In the present thesis, an extensive expe ...

EPFL2016

Basal entrainment by Newtonian gravity-driven flows

Nicolas Andreini, Christophe Ancey, Belinda Margaret Bates

Gravity-driven flows can erode the bed along which they descend and increase their mass by a factor of 10 or more. This process is called "basal entrainment." Although documented by field observations and laboratory experiments, it remains poorly understoo ...

Amer Inst Physics2016

Homoclinic snaking in plane Couette flow: bending, skewing and finite-size effects

Tobias Schneider

Invariant solutions of shear flows have recently been extended from spatially periodic solutions in minimal flow units to spatially localized solutions on extended domains. One set of spanwise-localized solutions of plane Couette flow exhibits homoclinic s ...

Cambridge University Press2016

Phase diagram for inertial granular flows

Eric DeGiuli, Matthieu Wyart

Flows of hard granular materials depend strongly on the interparticle friction coefficient mu(p) and on the inertial number I, which characterizes proximity to the jamming transition where flow stops. Guided by numerical simulations, we derive the phase di ...

2016

Dynamics of isolated confined air bubbles in liquid flows through circular microchannels: an experimental and numerical study

John Richard Thome, Navid Borhani, Sepideh Khodaparast, Mirco Magnini

Experimental and numerical studies are performed to characterise the dynamics of isolated confined air bubbles in laminar fully developed liquid flows within channels of diameters d = 0.5 mm and d = 1 mm. Water and glycerol are used as the continuous liqui ...

Springer Verlag2015