Publications by François Gallaire

Unsteady dynamical wetting: a review

The wetting dynamics is often considered in the frame of stationary conditions, i.e., when the contact-line advances or recedes at constant velocity. The purpose of many corresponding studies is then to determine a relationship between the contact-line vel ...

2025

Adjoint-aided Homogenisation for Flows Through Heterogeneous Membranes

François Gallaire, Edouard Boujo, Kevin Wittkowski

Porous membranes, like nets or filters, are thin structures that allow fluid to flow through their pores. Homogenisation can be used to rigorously link the flow velocity with the stresses on the membrane via several coefficients (e.g. permeability and slip ...

CAMBRIDGE UNIV PRESS2025

Tumbling elimination induced by permeability: An experimental approach

François Gallaire

Archetypal falling behaviors of impervious objects are classified into four modes: fluttering, tumbling, steady descent, and chaotic motion. The classical scenario predicts these behaviors to be affected by three dimensionless quantities: thickness-to-widt ...

2025

Releasing long bubbles trapped in thin capillaries via tube centrifugation and inclination

François Gallaire

In confined systems, the entrapment of a gas volume with an equivalent spherical diameter greater than the dimension of the channel can form extended bubbles that obstruct fluid circuits and compromise performance. Notably, in sealed vertical tubes, buoyan ...

Cambridge University Press2024

Coating thickness prediction for a viscous film on a rough plate

François Gallaire, John Martin Kolinski, Giuseppe Antonio Zampogna

Surface roughness significantly modifies the liquid film thickness entrained when dip coating a solid surface, particularly at low coating velocity. Using a homogenization approach, we present a predictive model for determining the liquid film thickness co ...

Cambridge University Press2024

Stick-slip-to-stick transition of liquid oscillations in a U-shaped tube

François Gallaire, Alessandro Bongarzone

The nonlinear decay of oscillations of a liquid column in a U-shaped tube is investigated within the theoretical framework of the projection method formalized by Bongarzone et al. [Chaos 31, 123124 (2021)]. Starting from the full hydrodynamic system supple ...

Amer Physical Soc2024

Stability of a liquid layer draining around a horizontal cylinder: Interplay of capillary and gravity forces

François Gallaire, Shahab Eghbali, Simeon Vladimirov Djambov

We study the drainage of a viscous liquid film coating the outside of a solid horizontal cylinder, where gravity acts vertically. We focus on the limit of large Ohnesorge numbers Oh, where inertia is negligible compared to viscous effects. We first study t ...

Amer Physical Soc2024

Lagrangian versus Eulerian view on the mean drift and streaming flows in orbital sloshing

François Gallaire, Alessandro Bongarzone

Orbital sloshing is a technique to gently mix a container's liquid content and it is commonly used in fermentation and cell cultivation processes. Besides the rich wave dynamics observed at the interface, Bouvard et al. [Phys. Rev. Fluids 2, 084801 (2017)2 ...

2024

Instability and trajectories of buoyancy-driven annular disks: A numerical study

François Gallaire, Pier Giuseppe Ledda, Giovanni Vagnoli

We investigate the stability of the steady vertical path and the emerging trajectories of a buoyancy -driven annular disk as the diameter of its central hole is varied. The steady and axisymmetric wake associated with the steady vertical path of the disk, ...

Amer Physical Soc2024

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

Boundary-layer approach to the linear karren instability

François Gallaire, Simeon Vladimirov Djambov

The present paper concerns the linear fate of transverse perturbations in a gravity-driven, thin-film flow over a soluble substrate. We propose a reduced-order model, based on a boundary-layer treatment of the solute transport and a depth-integration of th ...

Cambridge University Press2023

Von Karman vortex street past a permeable circular cylinder. Two-dimensional flow and dynamic-mode-decomposition-based secondary stability analysis

François Gallaire, Alessandro Bongarzone

We investigate the wake structure and the three-dimensional stability of the two-dimensional von Karman vortex street developing in the wake of a permeable circular cylinder. The flow through the porous medium, assumed homogenous and isotropic, is describe ...

Amer Physical Soc2023

A weakly nonlinear amplitude equation approach to the bypass transition in the two-dimensional Lamb–Oseen vortex

François Gallaire, Yves-Marie François Ducimetière

We analytically derive an amplitude equation for the weakly nonlinear evolution of the linearly most amplified response of a non-normal dynamical system. The development generalizes the method proposed in Ducimetière et al. (J. Fluid Mech., vol. 947, 2022, ...

Cambridge University Press2023

Homogenization theory captures macroscopic flow discontinuities across Janus membranes

François Gallaire, Pier Giuseppe Ledda, Giuseppe Antonio Zampogna, Kevin Wittkowski

Janus membranes, thin permeable structures with chemical and geometrical asymmetric properties, show great potential in industrial separation processes. Yet the link between the micro- and macro-scale behaviours of these membranes needs to be established r ...

Cambridge University Press2023

Liquid film instability of an internally coated horizontal tube

François Gallaire, Edouard Boujo, Yves-Marie François Ducimetière, Shahab Eghbali

We study numerically and theoretically the gravity-driven flow of a viscous liquid film coating the inner side of a horizontal cylindrical tube and surrounding a shear-free dynamically inert gaseous core. The liquid-gas interface is prone to the Rayleigh-P ...

AMER PHYSICAL SOC2023

A revised gap-averaged Floquet analysis of Faraday waves in Hele-Shaw cells

François Gallaire, Alessandro Bongarzone

Existing theoretical analyses of Faraday waves in Hele-Shaw cells rely on the Darcy approximation and assume a parabolic flow profile in the narrow direction. However, Darcy's model is known to be inaccurate when convective or unsteady inertial effects are ...

Cambridge University Press2023

Breaking one into three: Surface-tension-driven droplet breakup in T-junctions

Philippe Renaud, Arnaud Bertsch, François Gallaire, Daniel Migliozzi, Yves-Marie François Ducimetière, Jiande Zhou, Ludovic Pierre Gustave Keiser

Droplet breakup is an important phenomenon in the field of microfluidics to generate daughter droplets. In this work, a novel breakup regime in the widely studied T-junction geometry is reported, where the pinch-off occurs laterally in the two outlet chann ...

AMER PHYSICAL SOC2023

Weakly nonlinear versus semi-linear models of the nonlinear evolution of the centrifugal instability

François Gallaire, Eunok Yim

We carry out a weakly nonlinear analysis of the centrifugal instability for a columnar vortex in a rotating fluid, and compare the results to those of the semi-linear model derived empirically by Yim et al. (J. Fluid Mech., vol. 897, 2020, A34). The asympt ...

Cambridge University Press2023

Super-harmonically resonant swirling waves in longitudinally forced circular cylinders

François Gallaire, Alessandro Bongarzone, Alice Evelyne Julienne Marcotte

Resonant sloshing in circular cylinders was studied by Faltinsen et al. (J. Fluid Mech., vol. 804, 2016, pp. 608-645), whose theory was used to describe steady-state resonant waves due to a time-harmonic container's elliptic orbits. In the limit of longitu ...

Cambridge University Press2023

Swirling against the forcing: Evidence of stable counterdirected sloshing waves in orbital-shaken reservoirs

François Gallaire, Alessandro Bongarzone, Alice Evelyne Julienne Marcotte

We investigate the response of the free liquid surface in a partially filled circular cylindrical container undergoing a planar elliptic and time-periodic orbit while maintaining fixed its orientation. For small forcing amplitudes and deep liquid layers, w ...

Amer Physical Soc2023