Publications associées à Effects of chordwise flexibility on 2D flapping foils used as an energy extraction device

Noise-induced transitions past the onset of a steady symmetry-breaking bifurcation: The case of the sudden expansion

François Gallaire, Edouard Boujo, Yves-Marie François Ducimetière

We consider fluid flows, governed by the Navier-Stokes equations, subject to a steady symmetry-breaking bifurcation and forced by a weak noise acting on a slow timescale. By generalizing the multiple-scale weakly nonlinear expansion technique employed in t ...

2024

Short-term behavior of glass fiber-polymer composite bending-active elastica beam under service load application

Thomas Keller, Landolf-Giosef-Anastasios Rhode-Barbarigos, Tara Habibi

Bending-active elastica beam is a structural configuration that is based on the elastic deformation of an initially straight beam. This deformation occurs when horizontal displacements are applied to a sliding support, causing the beam to bend into an arch ...

2024

Deformation response of highly stretchable and ductile graphene kirigami under uniaxial and biaxial tension

Ye Wei, Yao Chen, Tong Guo

Kirigami, the ancient technique of paper cutting, has been successfully applied to enhance the stretchability and ductility of nanoscale graphene. However, existing experimentally realized graphene kirigami (GK) are created by introducing parallel cuts, ex ...

Amer Physical Soc2023

A Fast Hybrid Pressure-Correction Algorithm for Simulating Incompressible Flows by Projection Methods

Jiannong Fang

To enforce the conservation of mass principle, a pressure Poisson equation arises in the numerical solution of incompressible fluid flow using the pressure-based segregated algorithms such as projection methods. For unsteady flows, the pressure Poisson equ ...

2023

Visualization and modelling of dynamic flow in fibrous preforms for liquid composite molding

Helena Luisa Teixido Pedarros

Nowadays, Liquid Composite Molding techniques are often used to manufacture high quality fiber reinforced composite parts at a relatively low cost. These involve an infiltration process, in which a liquid resin is forced to ingress into a dry fibrous porou ...

EPFL2023

Numerical analysis of apparatus-induced dispersion for density-dependent solute transport in porous media

David Andrew Barry, Hong Zhang

The effects of apparatus-induced dispersion on nonuniform, density-dependent flow in a cylindrical soil column were investigated using a finite-element model. To validate the model, the results with an analytical solution and laboratory column test data we ...

2023

A fully-coupled highly-parallelized geomechanical simulator for assessing induced seismicity

Jean-François Molinari, Guillaume Anciaux, Nicolas Richart, Brice Tanguy Alphonse Lecampion, Emil Gallyamov

Induced seismicity caused by anthropogenic modification of the subsurface effective stress state has been observed in a number of industrial applications -- from hydrocarbon extraction (e.g., Groningen [1]), drilling waste-water disposal (e.g., [2]) to the ...

2023

Small-scale dynamo with finite correlation times

Jennifer Waltraud Schober

Fluctuation dynamos occur in most turbulent plasmas in astrophysics and are the prime candidates for amplifying and maintaining cosmic magnetic fields. A few analytical models exist to describe their behavior, but they are based on simplifying assumptions. ...

AMER PHYSICAL SOC2023

Highly Efficient Miniaturized Magnetorheological Valves Using Electropermanent Magnets

Christian Köchli, Yves Perriard, Adrien Jean-Michel Thabuis, Kenny Jeanmonod, Sofia Lydia Ntella, Bhawnath Tiwari

Fluidic systems enable actuation in various applications, such as automotive, medical, and industrial robotics. Miniaturized valves constitute a fundamental controlling element of modern fluidic systems, intriguing the interest of many researchers. This le ...

2023

Growth, timing, & trajectory of vortices behind a rotating plate

Diego Francescangeli

The presence of aerodynamic vortices is widespread in nature. They can be found at small scales near the wing tip of flying insects or at bigger scale in the form of hurricanes, cyclones or even galaxies. They are identified as coherent regions of high vor ...

EPFL2022

Experimental quantification of unsteady leading-edge flow separation

Karen Ann J Mulleners, Julien Dominique Claude Deparday

We propose here a method to experimentally quantify unsteady leading-edge flow separation on aerofoils with finite thickness. The methodology relies on the computation of a leading-edge suction parameter based on measured values of the partial circulation ...

Cambridge University Press2022

Transport across thin membranes: Effective solute flux jump

François Gallaire, Pier Giuseppe Ledda, Giuseppe Antonio Zampogna

A model to describe the transport across membranes of chemical species dissolved in an incompressible flow is developed via homogenization. The asymptotic matching between the microscopic and macroscopic solute concentration fields leads to a solute flux j ...

AIP Publishing2022

Scaling Description of Creep Flow in Amorphous Solids

Marko Popovic, Matthieu Wyart, Wencheng Ji, Thomas Willem Jan de Geus

Amorphous solids such as coffee foam, toothpaste, or mayonnaise display a transient creep flow when a stress E is suddenly imposed. The associated strain rate is commonly found to decay in time as gamma_ -t-nu, followed either by arrest or by a sudden flui ...

AMER PHYSICAL SOC2022

Effects of resonator geometry and substrate stiffness on the tunability of a deformable microwave metasurface

Taha Goudarzi, Romain Christophe Rémy Fleury, Rayehe Karimi Mahabadi

Tunable metasurfaces can shift their resonant frequency through different approaches, one of which is applying mechanical deformations. Here, we show the effects of two key factors on the tunability of deformable metasurfaces; the resonator geometry and su ...

2022

Weakly nonlinear evolution of stochastically driven non-normal systems

François Gallaire, Edouard Boujo, Yves-Marie François Ducimetière

We consider nonlinear dynamical systems driven by stochastic forcing. It has been largely evidenced in the literature that the linear response of non-normal systems (e.g. fluid flows) may exhibit a large variance amplification, even in a linearly stable re ...

Cambridge University Press2022

Eulerian simulation of complex suspensions and biolocomotion in three dimensions

Yuexia Luna Lin

We present a numerical method specifically designed for simulating three-dimensional fluid-structure interaction (FSI) problems based on the reference map technique (RMT). The RMT is a fully Eulerian FSI numerical method that allows fluids and large-deform ...

National Academy of Sciences2022

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

From coating flow patterns to porous body wake dynamics via multiscale models

Pier Giuseppe Ledda

Multiscale phenomena are involved in countless problems in fluid mechanics. Coating flows are known to exhibit a broad variety of patterns, such as wine tears in a glass and dripping of fresh paint applied on a wall. Coating flows are typically modeled und ...

EPFL2022

Stick-slip phenomena and Schallamach waves captured using reversible cohesive elements

Jean-François Molinari, Thibault Didier Roch, Evelyne Pélagie Ringoot

Reversibility is of paramount importance in the correct representation of surface peeling in various physical settings, ranging from motility in nature, to gripping devices in robotic applications, and even to sliding of tectonic plates. Modeling the detac ...

PERGAMON-ELSEVIER SCIENCE LTD2021

Hydraulic fracture growth in quasi-brittle materials

Dong Liu

Hydraulic fracturing is a technique often used in the oil and gas industry to enhance the production of wells in low-permeability reservoirs. It consists of fluid injection at a sufficiently large injection rate to create and propagate tensile fractures in ...

EPFL2021