Jose E . Wesfreid | ESPCI ParisTech (original) (raw)

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Papers by Jose E . Wesfreid

Research paper thumbnail of Experimental investigation of the wake behind a rotating sphere

Physical review fluids, Jan 23, 2018

Research paper thumbnail of La tour Eiffel, premier laboratoire d’aérodynamique en France

Research paper thumbnail of The Self-Sustaining Process for Taylor-vortex flow

Bulletin of the American Physical Society, Nov 25, 2014

Research paper thumbnail of Experimental measurements of large scale flow in plane Couette-Poiseuille flow

Research paper thumbnail of New experiment in Plane Poiseuille flow with zero mean advection velocity: observation of stationary turbulent spots

Bulletin of the American Physical Society, Nov 24, 2015

Research paper thumbnail of Flujo Axial Sobre Vórtices De Taylor-Couette

ANALES AFA, Sep 17, 2013

Se presentan los resultados experimentales sobre el comportamiento en funcion del tiempo de un tr... more Se presentan los resultados experimentales sobre el comportamiento en funcion del tiempo de un trazador inyectado en un flujo de Taylor-Couette sobre el que se superpuso un flujo axial continuo. Se trabajo con un equipo de Taylor-Couette de gap pequeno. La longitud es L=32cm, el radio del cilindro interior es de 45mm y el cociente entre los radios del cilindro interior y exterior es n=R1/R2=0.79. Se inyecto un pulso de fluorescencia a t=0 cerca del cilindro interior en la posicion L/2. Por medio de secuencias fotograficas se estudio la estabilidad y propagacion de los vortices de Taylor en funcion del caudal del flujo lateral. Con el objeto de estudiar la dispersion del trazador inyectado, se midio la concentracion del mismo en funcion del tiempo en el liquido efluente.

Research paper thumbnail of Velocity Field Structure and Semiquantitative Analysis of Tracer Dispersion in a Taylor-Vortex Flow of Wide Gap

An experimental study of the velocity field structure of stationary Taylor Vortex Flow of Wide Ga... more An experimental study of the velocity field structure of stationary Taylor Vortex Flow of Wide Gap is performed by visualization in a range of high Reynolds numbers. The tracer dispersion in the flow field shows a short wavelength modulation throughout the structure.

Research paper thumbnail of Experiments on a jet in a crossflow in the low-velocity-ratio regime

Journal of Fluid Mechanics, Jan 29, 2019

Research paper thumbnail of Forced wakes far from threshold: Stuart-Landau equation applied to experimental data

Physical review fluids, Sep 10, 2018

Research paper thumbnail of Spatiotemporal spectral analysis of a forced cylinder wake

Physical Review E, Nov 14, 2011

Research paper thumbnail of Self-sustaining process in Taylor-Couette flow

Physical review fluids, Dec 21, 2018

Research paper thumbnail of Cellular structures in instabilities : proceedings of the Meeting "Structures cellulaires dans les instabilités - périodicité, défauts, turbulence de phase" held at Gif-sur Yvette, France, June 20-22, 1983

Springer eBooks, 1984

Cellular structures in instabilities : An introduction.- Rayleigh-Benard instability : Experiment... more Cellular structures in instabilities : An introduction.- Rayleigh-Benard instability : Experimental study of the wavenumber selection.- Wavelength selection and pattern localization in buckling problems.- Wavenumber selection in buckling experiments.- Effect of boundaries on periodic patterns.- Cell number selection in Taylor-Couette flow.- Wavelength selection through boundaries in 1-D cellular structures.- Wavenumber selection in Rayleigh-Benard convective structure.- Convection patterns in large aspect ratio systems.- Three dimensional convective structttres in a horizontal or tilted porous layer.- Modelisation and simulation of convection in extended geometry.- Pattern evolution from convective and electrohydrodynamic instabilities.- Amplitude equations for non linear convection in high vertical channels.- Stability of cellular systems in Taylor-Couette instability.- Spatial dissipative structures and hydrodynamic instabilities.- Chemical structures far from equilibrium.- Structure defects in Benard-Marangoni instability.- Non adiabatic phenomena in cellular structures.- Smectics : A model for dynamical systems?.- Defects and interactions with the structures in ehd convection in nematic liquid crystals.- Quantitative study pf the disorganization of hexagonal convective structures.- Shear modes in low-prandtl thermal convection.- Spatial instabilities and temporal chaos.- Temporal and spatial aspects of the onset of chaos in a Taylor instability subjected to a magnetic field.- Electro-hydro-dynamical convective structures and transitions to chaos in a liquid crystal.- Rotating disk flows, transition to turbulence.- Morphological instabilities in the solidification front of binary mixtures.- Cellular structures on premixed flames in a uniform laminar flow.- Energy in the Benard-Rayleigh problem.- Modelisation of thermoconvective instabilities in saturated porous media- lateral boundary influence.- Competition between marangoni and archimedean forces, to determine the surface profile of a liquid heated, open to air.- Surface relief accompanying natural convection in liquid layers heated from below.- On the subject of Gortler vortex.

Research paper thumbnail of Propagating localized structures in a 1D Faraday experiment

APS Division of Fluid Dynamics Meeting Abstracts, 2020

Research paper thumbnail of Flow instabilities behind rotating bluff bodies for moderate Reynolds number

APS Division of Fluid Dynamics Meeting Abstracts, Nov 1, 2015

Research paper thumbnail of Propagating oscillons in a 1Dim. Faraday experiment

Bulletin of the American Physical Society, Mar 4, 2020

Research paper thumbnail of Anisotropic decay of turbulence in plane Couette-Poiseuille flow

arXiv (Cornell University), Aug 20, 2020

Research paper thumbnail of Frequency predictions from global stability in the Benard vortex street

Bulletin of the American Physical Society, Nov 19, 2018

Research paper thumbnail of First instabilities of the wake behind a rotating sphere

Bulletin of the American Physical Society, Nov 24, 2014

Research paper thumbnail of Dynamic mode decomposition analysis of instability of the flow past rotating sphere

Bulletin of the American Physical Society, Nov 25, 2014

Research paper thumbnail of Dynamics of a floating particle in the presence of an external force

Journal of Physics D, May 31, 2000

The present article describes an experimental study of the dynamics of a small magnetic particle ... more The present article describes an experimental study of the dynamics of a small magnetic particle moving on the flat horizontal free surface of a rotating liquid and submitted to a magnetic field that decreases with distance from a dipole magnet. The particle is kept at the surface by interface forces and its motion is bidimensional. For a constant external force, its behaviour displays a transition at a threshold angular rotation velocity Ω = Ωc. Below the threshold, the particle remains at a fixed point; above the threshold, its trajectory tends towards a limit cycle of ovoidal shape and size increasing with Ω. A phenomenological modification of the equation that describes the motion of the particle is suggested in order to represent the influence of capillary effects on the particle trajectory: an effective drag coefficient is introduced that decreases the inertial response time of the particle. The numerical integration of the equation agrees with experimental observations. Nonlinear effects for a time-dependent magnetic field have been studied in the case of a square wave variation of frequency ω. The shape of the Poincare sections is shown to depend on the ratio ω/Ω. Starting from the disc angular coordinate, a circle map may be constructed which shows an almost one-dimensional behaviour.

Research paper thumbnail of Experimental investigation of the wake behind a rotating sphere

Physical review fluids, Jan 23, 2018

Research paper thumbnail of La tour Eiffel, premier laboratoire d’aérodynamique en France

Research paper thumbnail of The Self-Sustaining Process for Taylor-vortex flow

Bulletin of the American Physical Society, Nov 25, 2014

Research paper thumbnail of Experimental measurements of large scale flow in plane Couette-Poiseuille flow

Research paper thumbnail of New experiment in Plane Poiseuille flow with zero mean advection velocity: observation of stationary turbulent spots

Bulletin of the American Physical Society, Nov 24, 2015

Research paper thumbnail of Flujo Axial Sobre Vórtices De Taylor-Couette

ANALES AFA, Sep 17, 2013

Se presentan los resultados experimentales sobre el comportamiento en funcion del tiempo de un tr... more Se presentan los resultados experimentales sobre el comportamiento en funcion del tiempo de un trazador inyectado en un flujo de Taylor-Couette sobre el que se superpuso un flujo axial continuo. Se trabajo con un equipo de Taylor-Couette de gap pequeno. La longitud es L=32cm, el radio del cilindro interior es de 45mm y el cociente entre los radios del cilindro interior y exterior es n=R1/R2=0.79. Se inyecto un pulso de fluorescencia a t=0 cerca del cilindro interior en la posicion L/2. Por medio de secuencias fotograficas se estudio la estabilidad y propagacion de los vortices de Taylor en funcion del caudal del flujo lateral. Con el objeto de estudiar la dispersion del trazador inyectado, se midio la concentracion del mismo en funcion del tiempo en el liquido efluente.

Research paper thumbnail of Velocity Field Structure and Semiquantitative Analysis of Tracer Dispersion in a Taylor-Vortex Flow of Wide Gap

An experimental study of the velocity field structure of stationary Taylor Vortex Flow of Wide Ga... more An experimental study of the velocity field structure of stationary Taylor Vortex Flow of Wide Gap is performed by visualization in a range of high Reynolds numbers. The tracer dispersion in the flow field shows a short wavelength modulation throughout the structure.

Research paper thumbnail of Experiments on a jet in a crossflow in the low-velocity-ratio regime

Journal of Fluid Mechanics, Jan 29, 2019

Research paper thumbnail of Forced wakes far from threshold: Stuart-Landau equation applied to experimental data

Physical review fluids, Sep 10, 2018

Research paper thumbnail of Spatiotemporal spectral analysis of a forced cylinder wake

Physical Review E, Nov 14, 2011

Research paper thumbnail of Self-sustaining process in Taylor-Couette flow

Physical review fluids, Dec 21, 2018

Research paper thumbnail of Cellular structures in instabilities : proceedings of the Meeting "Structures cellulaires dans les instabilités - périodicité, défauts, turbulence de phase" held at Gif-sur Yvette, France, June 20-22, 1983

Springer eBooks, 1984

Cellular structures in instabilities : An introduction.- Rayleigh-Benard instability : Experiment... more Cellular structures in instabilities : An introduction.- Rayleigh-Benard instability : Experimental study of the wavenumber selection.- Wavelength selection and pattern localization in buckling problems.- Wavenumber selection in buckling experiments.- Effect of boundaries on periodic patterns.- Cell number selection in Taylor-Couette flow.- Wavelength selection through boundaries in 1-D cellular structures.- Wavenumber selection in Rayleigh-Benard convective structure.- Convection patterns in large aspect ratio systems.- Three dimensional convective structttres in a horizontal or tilted porous layer.- Modelisation and simulation of convection in extended geometry.- Pattern evolution from convective and electrohydrodynamic instabilities.- Amplitude equations for non linear convection in high vertical channels.- Stability of cellular systems in Taylor-Couette instability.- Spatial dissipative structures and hydrodynamic instabilities.- Chemical structures far from equilibrium.- Structure defects in Benard-Marangoni instability.- Non adiabatic phenomena in cellular structures.- Smectics : A model for dynamical systems?.- Defects and interactions with the structures in ehd convection in nematic liquid crystals.- Quantitative study pf the disorganization of hexagonal convective structures.- Shear modes in low-prandtl thermal convection.- Spatial instabilities and temporal chaos.- Temporal and spatial aspects of the onset of chaos in a Taylor instability subjected to a magnetic field.- Electro-hydro-dynamical convective structures and transitions to chaos in a liquid crystal.- Rotating disk flows, transition to turbulence.- Morphological instabilities in the solidification front of binary mixtures.- Cellular structures on premixed flames in a uniform laminar flow.- Energy in the Benard-Rayleigh problem.- Modelisation of thermoconvective instabilities in saturated porous media- lateral boundary influence.- Competition between marangoni and archimedean forces, to determine the surface profile of a liquid heated, open to air.- Surface relief accompanying natural convection in liquid layers heated from below.- On the subject of Gortler vortex.

Research paper thumbnail of Propagating localized structures in a 1D Faraday experiment

APS Division of Fluid Dynamics Meeting Abstracts, 2020

Research paper thumbnail of Flow instabilities behind rotating bluff bodies for moderate Reynolds number

APS Division of Fluid Dynamics Meeting Abstracts, Nov 1, 2015

Research paper thumbnail of Propagating oscillons in a 1Dim. Faraday experiment

Bulletin of the American Physical Society, Mar 4, 2020

Research paper thumbnail of Anisotropic decay of turbulence in plane Couette-Poiseuille flow

arXiv (Cornell University), Aug 20, 2020

Research paper thumbnail of Frequency predictions from global stability in the Benard vortex street

Bulletin of the American Physical Society, Nov 19, 2018

Research paper thumbnail of First instabilities of the wake behind a rotating sphere

Bulletin of the American Physical Society, Nov 24, 2014

Research paper thumbnail of Dynamic mode decomposition analysis of instability of the flow past rotating sphere

Bulletin of the American Physical Society, Nov 25, 2014

Research paper thumbnail of Dynamics of a floating particle in the presence of an external force

Journal of Physics D, May 31, 2000

The present article describes an experimental study of the dynamics of a small magnetic particle ... more The present article describes an experimental study of the dynamics of a small magnetic particle moving on the flat horizontal free surface of a rotating liquid and submitted to a magnetic field that decreases with distance from a dipole magnet. The particle is kept at the surface by interface forces and its motion is bidimensional. For a constant external force, its behaviour displays a transition at a threshold angular rotation velocity Ω = Ωc. Below the threshold, the particle remains at a fixed point; above the threshold, its trajectory tends towards a limit cycle of ovoidal shape and size increasing with Ω. A phenomenological modification of the equation that describes the motion of the particle is suggested in order to represent the influence of capillary effects on the particle trajectory: an effective drag coefficient is introduced that decreases the inertial response time of the particle. The numerical integration of the equation agrees with experimental observations. Nonlinear effects for a time-dependent magnetic field have been studied in the case of a square wave variation of frequency ω. The shape of the Poincare sections is shown to depend on the ratio ω/Ω. Starting from the disc angular coordinate, a circle map may be constructed which shows an almost one-dimensional behaviour.