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Eric Falcon - One of the best experts on this subject based on the ideXlab platform.
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experiments in surface gravity Capillary Wave turbulence
Annual Review of Fluid Mechanics, 2022Co-Authors: Eric Falcon, Nicolas MordantAbstract:The last decade has seen a significant increase in the number of studies devoted to Wave turbulence. Many deal with water Waves, as modeling of ocean Waves has historically motivated the developmen...
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experiments in surface gravity Capillary Wave turbulence
arXiv: Fluid Dynamics, 2021Co-Authors: Eric Falcon, Nicolas MordantAbstract:The last decade has seen a significant increase in the number of studies devoted to Wave turbulence. Many deal with water Waves, as modeling of ocean Waves has historically motivated the development of weak turbulence theory, which adresses the dynamics of a random ensemble of weakly nonlinear Waves in interaction. Recent advances in experiments have shown that this theoretical picture is too idealized to capture experimental observations. While gravity dominates much of the oceanic spectrum, Waves observed in the laboratory are in fact gravity-Capillary Waves, due to the restricted size of Wave basins. This richer physics induces many interleaved physical effects far beyond the theoretical framework, notably in the vicinity of the gravity-Capillary crossover. These include dissipation, finite-system size effects, and finite nonlinearity effects. Simultaneous space-and-time resolved techniques, now available, open the way for a much more advanced analysis of these effects.
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Numerical Simulation of Collinear Capillary-Wave Turbulence
JETP Letters, 2020Co-Authors: Evgeny A. Kochurin, Guillaume Ricard, Nikolay M. Zubarev, Eric FalconAbstract:We report on direct numerical simulation of quasi-one-dimensional bidirectional Capillary-Wave turbulence. Although nontrivial three-Wave and four-Wave resonant interactions are absent in this peculiar geometry, we show that an energy transfer between scales still occurs concentrated around the linear dispersion relation that is broadened by nonlinearity. The Wave spectrum displays a clear Wave number power-law scaling that is found to be in good agreement with the dimensionally prediction for Capillary-Wave turbulence involving four-Wave interactions. The carried out high-order correlation analysis (bicoherence and tricoherence) confirms quantitatively the dominant role of four-Wave quasi-resonant interactions. The Kolmogorov-Zakharov spectrum constant is also estimated numerically. We interpret our results as the first numerical observation of anisotropic Capillary-Wave turbulence in which four-Wave interactions play a dominant role
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Capillary Wave turbulence experiments in microgravity
EPL (Europhysics Letters), 2020Co-Authors: Michaël Berhanu, Eric Falcon, Guillaume Michel, Christophe Gissinger, Stéphan FauveAbstract:Using the FLUIDICS (Fluid Dynamics in Space) experiment in the International Space Station, turbulence of Capillary Waves at the air-water interface is experimentally investigated in weightlessness. Capillary Waves are excited in a spherical container partially filled with water and undergoing sinusoidal or random oscillations. The fluctuations of the interface, recorded with two capacitive probes are analyzed by means of the frequency power spectrum of Wave elevation. For high enough forcing amplitudes, we report power-law spectra with exponents close to the prediction of weak Wave turbulence theory. However, in this experiment the free-surface steepness is not small compared to 1 and thus the investigated regimes correspond to strongly nonlinear Wave turbulence.
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direct numerical simulations of Capillary Wave turbulence
Physical Review Letters, 2014Co-Authors: Luc Deike, Michaël Berhanu, Daniel Fuster, Eric FalconAbstract:This work presents direct numerical simulations of Capillary Wave turbulence solving the full three-dimensional Navier-Stokes equations of a two-phase flow. When the interface is locally forced at large scales, a statistical stationary state appears after few forcing periods. Smaller Wave scales are generated by nonlinear interactions, and the Wave height spectrum is found to obey a power law in both Wave number and frequency, in good agreement with weak turbulence theory. By estimation of the mean energy flux from the dissipated power, the Kolmogorov-Zakharov constant is evaluated and found to be compatible with the exact theoretical value. The time scale separation between linear, nonlinear interaction, and dissipative times is also observed. These numerical results confirm the validity of the weak turbulence approach to quantify out-of equilibrium Wave statistics.
Stéphan Fauve - One of the best experts on this subject based on the ideXlab platform.
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Capillary Wave turbulence experiments in microgravity
EPL (Europhysics Letters), 2020Co-Authors: Michaël Berhanu, Eric Falcon, Guillaume Michel, Christophe Gissinger, Stéphan FauveAbstract:Using the FLUIDICS (Fluid Dynamics in Space) experiment in the International Space Station, turbulence of Capillary Waves at the air-water interface is experimentally investigated in weightlessness. Capillary Waves are excited in a spherical container partially filled with water and undergoing sinusoidal or random oscillations. The fluctuations of the interface, recorded with two capacitive probes are analyzed by means of the frequency power spectrum of Wave elevation. For high enough forcing amplitudes, we report power-law spectra with exponents close to the prediction of weak Wave turbulence theory. However, in this experiment the free-surface steepness is not small compared to 1 and thus the investigated regimes correspond to strongly nonlinear Wave turbulence.
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observation of thermal equilibrium in Capillary Wave turbulence
Physical Review Letters, 2017Co-Authors: Guillaume Michel, Francois Petrelis, Stéphan FauveAbstract:We investigate Capillary Wave turbulence at scales larger than the forcing one. At such scales, our measurements show that the surface Waves dynamics is the one of a thermal equilibrium state in which the effective temperature is related to the injected power. We characterize this evolution with a scaling law and report the statistical properties of the large-scale surface elevation depending on this effective temperature.
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Capillary Wave turbulence on a spherical fluid surface in low gravity
EPL, 2009Co-Authors: Claudio Falcon, Umberto Bortolozzo, Eric Falcon, Stéphan FauveAbstract:We report the observation of Capillary Wave turbulence on the surface of a fluid layer in a low-gravity environment. In such conditions, the fluid covers all the internal surface of the spherical container that is submitted to random forcing. The surface Wave amplitude displays power law spectrum over two decades in frequency, corresponding to Wavelength from millimeters to a few centimeters. This spectrum is found in roughly good agreement with Wave turbulence theory. Such a large-scale observation without gravity Waves has never been reached during ground experiments. When the forcing is periodic, two-dimensional spherical patterns are observed on the fluid surface such as subharmonic stripes or hexagons with Wavelength satisfying the Capillary Wave dispersion relation.
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Capillary Wave turbulence on a spherical fluid surface in low gravity
EPL - Europhysics Letters, 2009Co-Authors: Claudio Falcon, Umberto Bortolozzo, Eric Falcon, Stéphan FauveAbstract:We report the observation of Capillary Wave turbulence on the surface of a fluid layer in a low-gravity environment. In such conditions, the fluid covers all the internal surface of the spherical container which is submitted to random forcing. The surface Wave amplitude displays power-law spectrum over two decades in frequency, corresponding to Wavelength from $mm$ to a few $cm$. This spectrum is found in roughly good agreement with Wave turbulence theory. Such a large scale observation without gravity Waves has never been reached during ground experiments. When the forcing is periodic, two-dimensional spherical patterns are observed on the fluid surface such as subharmonic stripes or hexagons with Wavelength satisfying the Capillary Wave dispersion relation.
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Observation of gravity-Capillary Wave turbulence
Physical Review Letters, 2007Co-Authors: Eric Falcon, Claude Laroche, Stéphan FauveAbstract:We report the observation of the cross-over between gravity and Capillary Wave turbulence on the surface of mercury. The probability density functions of the turbulent Wave height are found to be asymmetric and thus non Gaussian. The surface Wave height displays power-law spectra in both regimes. In the Capillary region, the exponent is in fair agreement with weak turbulence theory. In the gravity region, it depends on the forcing parameters. This can be related to the finite size of the container. In addition, the scaling of those spectra with the mean energy flux is found in disagreement with weak turbulence theory for both regimes.
P Tarazona - One of the best experts on this subject based on the ideXlab platform.
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density correlation in liquid surfaces bedeaux weeks high order terms and non Capillary Wave background
Journal of Chemical Physics, 2018Co-Authors: Jose Hernandezmunoz, E Chacon, P TarazonaAbstract:We present Molecular Dynamics (MD) simulations of liquid-vapor surfaces, and their Intrinsic Sampling Method analysis, to get a quantitative test for the theoretical prediction of the Capillary Wave (CW) effects on density correlation done by Bedeaux and Weeks (BW) in 1985. The results are contrasted with Wertheim’s proposal which is the first term in BW series and are complemented with a (formally defined and computational accessible) proposal for the background of non-CW fluctuations. Our conclusion is that BW theory is both accurate and needed since it may differ significantly from Wertheim’s proposal. We discuss the implications for the analysis of experimental X-ray surface diffraction data and MD simulations.We present Molecular Dynamics (MD) simulations of liquid-vapor surfaces, and their Intrinsic Sampling Method analysis, to get a quantitative test for the theoretical prediction of the Capillary Wave (CW) effects on density correlation done by Bedeaux and Weeks (BW) in 1985. The results are contrasted with Wertheim’s proposal which is the first term in BW series and are complemented with a (formally defined and computational accessible) proposal for the background of non-CW fluctuations. Our conclusion is that BW theory is both accurate and needed since it may differ significantly from Wertheim’s proposal. We discuss the implications for the analysis of experimental X-ray surface diffraction data and MD simulations.
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density correlation in liquid surfaces bedeaux weeks high order terms and non Capillary Wave background
Journal of Chemical Physics, 2018Co-Authors: Jose Hernandezmunoz, E Chacon, P TarazonaAbstract:We present Molecular Dynamics (MD) simulations of liquid-vapor surfaces, and their Intrinsic Sampling Method analysis, to get a quantitative test for the theoretical prediction of the Capillary Wave (CW) effects on density correlation done by Bedeaux and Weeks (BW) in 1985. The results are contrasted with Wertheim's proposal which is the first term in BW series and are complemented with a (formally defined and computational accessible) proposal for the background of non-CW fluctuations. Our conclusion is that BW theory is both accurate and needed since it may differ significantly from Wertheim's proposal. We discuss the implications for the analysis of experimental X-ray surface diffraction data and MD simulations.
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Capillary Waves and the decay of density correlations at liquid surfaces
Physical Review E, 2016Co-Authors: Jose Hernandezmunoz, E Chacon, P TarazonaAbstract:Wertheim predicted strong density-density correlations at free liquid surfaces, produced by Capillary Wave fluctuations of the interface [M. S. Wertheim, J. Chem. Phys. 65, 2377 (1976)JCPSA60021-960610.1063/1.433352]. That prediction has been used to search for a link between Capillary Wave (CW) theory and density functional (DF) formalism for classical fluids. In particular, Parry et al. have recently analyzed the decaying tails of these CW effects moving away from the interface as a clue for the extended CW theory [A. O. Parry et al., J. Phys.: Condens. Matter 28, 244013 (2016)JCOMEL0953-898410.1088/0953-8984/28/24/244013], beyond the strict long-Wavelength limit studied by Wertheim. Some apparently fundamental inconsistencies between the CW and the DF theoretical views of the fluid interfaces arose from the asymptotic analysis of the CW signal. In this paper we revisit the problem of the CW asymptotic decay with a separation of local non-CW surface correlation effects from those that are a truly nonlocal propagation of the CW fluctuations from the surface towards the liquid bulk.
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Capillary Wave hamiltonian for the landau ginzburg wilson density functional
Journal of Physics: Condensed Matter, 2016Co-Authors: E Chacon, P TarazonaAbstract:We study the link between the density functional (DF) formalism and the Capillary Wave theory (CWT) for liquid surfaces, focused on the Landau-Ginzburg-Wilson (LGW) model, or square gradient DF expansion, with a symmetric double parabola free energy, which has been extensively used in theoretical studies of this problem. We show the equivalence between the non-local DF results of Parry and coworkers and the direct evaluation of the mean square fluctuations of the intrinsic surface, as is done in the intrinsic sampling method for computer simulations. The definition of effective Wave-vector dependent surface tensions is reviewed and we obtain new proposals for the LGW model. The surface weight proposed by Blokhuis and the surface mode analysis proposed by Stecki provide consistent and optimal effective definitions for the extended CWT Hamiltonian associated to the DF model. A non-local, or coarse-grained, definition of the intrinsic surface provides the missing element to get the mesoscopic surface Hamiltonian from the molecular DF description, as had been proposed a long time ago by Dietrich and coworkers.
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effect of dispersion forces on the Capillary Wave fluctuations of liquid surfaces
Physical Review E, 2014Co-Authors: E Chacon, Eva M Fernandez, P TarazonaAbstract:We present molecular dynamics evidence for the nonanalytic effects of the long-range dispersion forces on the Capillary Waves fluctuations of a Lennard-Jones liquid surface. The results of the intrinsic sampling method, for the analysis of the instantaneous interfacial shape, are obtained in large systems for several cut-off distances of the potential tail, and they show good agreement with the theoretical prediction by Napi\'orkowski and Dietrich, based on a density functional analysis. The enhancement of the Capillary Waves is quantified to be within 1% for a simple liquid near its triple point.
E Chacon - One of the best experts on this subject based on the ideXlab platform.
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density correlation in liquid surfaces bedeaux weeks high order terms and non Capillary Wave background
Journal of Chemical Physics, 2018Co-Authors: Jose Hernandezmunoz, E Chacon, P TarazonaAbstract:We present Molecular Dynamics (MD) simulations of liquid-vapor surfaces, and their Intrinsic Sampling Method analysis, to get a quantitative test for the theoretical prediction of the Capillary Wave (CW) effects on density correlation done by Bedeaux and Weeks (BW) in 1985. The results are contrasted with Wertheim’s proposal which is the first term in BW series and are complemented with a (formally defined and computational accessible) proposal for the background of non-CW fluctuations. Our conclusion is that BW theory is both accurate and needed since it may differ significantly from Wertheim’s proposal. We discuss the implications for the analysis of experimental X-ray surface diffraction data and MD simulations.We present Molecular Dynamics (MD) simulations of liquid-vapor surfaces, and their Intrinsic Sampling Method analysis, to get a quantitative test for the theoretical prediction of the Capillary Wave (CW) effects on density correlation done by Bedeaux and Weeks (BW) in 1985. The results are contrasted with Wertheim’s proposal which is the first term in BW series and are complemented with a (formally defined and computational accessible) proposal for the background of non-CW fluctuations. Our conclusion is that BW theory is both accurate and needed since it may differ significantly from Wertheim’s proposal. We discuss the implications for the analysis of experimental X-ray surface diffraction data and MD simulations.
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density correlation in liquid surfaces bedeaux weeks high order terms and non Capillary Wave background
Journal of Chemical Physics, 2018Co-Authors: Jose Hernandezmunoz, E Chacon, P TarazonaAbstract:We present Molecular Dynamics (MD) simulations of liquid-vapor surfaces, and their Intrinsic Sampling Method analysis, to get a quantitative test for the theoretical prediction of the Capillary Wave (CW) effects on density correlation done by Bedeaux and Weeks (BW) in 1985. The results are contrasted with Wertheim's proposal which is the first term in BW series and are complemented with a (formally defined and computational accessible) proposal for the background of non-CW fluctuations. Our conclusion is that BW theory is both accurate and needed since it may differ significantly from Wertheim's proposal. We discuss the implications for the analysis of experimental X-ray surface diffraction data and MD simulations.
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Capillary Waves and the decay of density correlations at liquid surfaces
Physical Review E, 2016Co-Authors: Jose Hernandezmunoz, E Chacon, P TarazonaAbstract:Wertheim predicted strong density-density correlations at free liquid surfaces, produced by Capillary Wave fluctuations of the interface [M. S. Wertheim, J. Chem. Phys. 65, 2377 (1976)JCPSA60021-960610.1063/1.433352]. That prediction has been used to search for a link between Capillary Wave (CW) theory and density functional (DF) formalism for classical fluids. In particular, Parry et al. have recently analyzed the decaying tails of these CW effects moving away from the interface as a clue for the extended CW theory [A. O. Parry et al., J. Phys.: Condens. Matter 28, 244013 (2016)JCOMEL0953-898410.1088/0953-8984/28/24/244013], beyond the strict long-Wavelength limit studied by Wertheim. Some apparently fundamental inconsistencies between the CW and the DF theoretical views of the fluid interfaces arose from the asymptotic analysis of the CW signal. In this paper we revisit the problem of the CW asymptotic decay with a separation of local non-CW surface correlation effects from those that are a truly nonlocal propagation of the CW fluctuations from the surface towards the liquid bulk.
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Capillary Wave hamiltonian for the landau ginzburg wilson density functional
Journal of Physics: Condensed Matter, 2016Co-Authors: E Chacon, P TarazonaAbstract:We study the link between the density functional (DF) formalism and the Capillary Wave theory (CWT) for liquid surfaces, focused on the Landau-Ginzburg-Wilson (LGW) model, or square gradient DF expansion, with a symmetric double parabola free energy, which has been extensively used in theoretical studies of this problem. We show the equivalence between the non-local DF results of Parry and coworkers and the direct evaluation of the mean square fluctuations of the intrinsic surface, as is done in the intrinsic sampling method for computer simulations. The definition of effective Wave-vector dependent surface tensions is reviewed and we obtain new proposals for the LGW model. The surface weight proposed by Blokhuis and the surface mode analysis proposed by Stecki provide consistent and optimal effective definitions for the extended CWT Hamiltonian associated to the DF model. A non-local, or coarse-grained, definition of the intrinsic surface provides the missing element to get the mesoscopic surface Hamiltonian from the molecular DF description, as had been proposed a long time ago by Dietrich and coworkers.
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effect of dispersion forces on the Capillary Wave fluctuations of liquid surfaces
Physical Review E, 2014Co-Authors: E Chacon, Eva M Fernandez, P TarazonaAbstract:We present molecular dynamics evidence for the nonanalytic effects of the long-range dispersion forces on the Capillary Waves fluctuations of a Lennard-Jones liquid surface. The results of the intrinsic sampling method, for the analysis of the instantaneous interfacial shape, are obtained in large systems for several cut-off distances of the potential tail, and they show good agreement with the theoretical prediction by Napi\'orkowski and Dietrich, based on a density functional analysis. The enhancement of the Capillary Waves is quantified to be within 1% for a simple liquid near its triple point.
Akihide Hibara - One of the best experts on this subject based on the ideXlab platform.
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spherical spontaneous Capillary Wave resonance on optically trapped aerosol droplet
Journal of Physical Chemistry C, 2018Co-Authors: Akihide Hibara, Takuya Endo, Kyohei Ishikawa, Mao Fukuyama, Masaru Uraoka, Shoji IshizakaAbstract:We report a contactless surface tension measurement method of micrometer-sized aerosol droplets. In this method, we assume spherical spontaneous resonance of a thermally induced Capillary Wave. Fir...
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Spherical Spontaneous Capillary-Wave Resonance on Optically Trapped Aerosol Droplet
2018Co-Authors: Takuya Endo, Kyohei Ishikawa, Mao Fukuyama, Masaru Uraoka, Shoji Ishizaka, Akihide HibaraAbstract:We report a contactless surface tension measurement method of micrometer-sized aerosol droplets. In this method, we assume spherical spontaneous resonance of a thermally induced Capillary Wave. First, an aerosol droplet with a radius ranging from 4.7 to 12.4 μm is trapped by means of a simple single-beam optical trapping configuration, and the frequency shift power spectrum of the light passing the droplet is measured. The spectrum in each case exhibits several peaks in a frequency range of several tens to several hundred kilohertz. The peak frequencies agree well with theoretical ones predicted by the spherical resonant modes. After validating the above-mentioned assumption, we measure the surface tension of aerosol droplets containing sodium dodecyl sulfate, and we successfully obtain the surface tension value. The present method utilizes just two phenomena, that is, the droplet surface light scattering and spontaneous resonance of the Capillary Wave. These can be easily observed in aerosol droplets, and they can be utilized to gain scientific insights. The present method based on the nature of droplets can be used in various applications in aerosol science
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micro nano surface tension measurement by 2d Capillary Wave resonance
17th International Conference on Miniaturized Systems for Chemistry and Life Sciences MicroTAS 2013, 2013Co-Authors: Myungwha Chung, Christian Pigot, Akihide Hibara, Cnrsiis UmiAbstract:The analysis of Capillary Waves in confined microspace by quasi-elastic laser scattering (QELS) method enables surface tension measurements. In contrast to previous works, a simple single-beam-focusing method based on spontaneous Capillary Wave resonance with its confined size is proposed. The Capillary Wave resonance has been successfully demonstrated in confined two-dimensional micro surface at circular apertures. Moreover, the surface tension dependence on surfactant concentration has been successfully measured at 44-µm-sized circular liquid surface. This method is expected to be a powerful tool for bio and chemical sensing at micro- / nano-scale liquid interfaces.
