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580 results on '"Laboratoire Ondes et Milieux Complexes (LOMC)"'

1. Citric Acid-Enhanced Electroremediation of Toxic Metals from Dredged Sediments: Effect of Open/Closed Orifice Condition, Electric Potential and Surfactant

Author

Song , Yue, Benamar , Ahmed, Mezazigh , S., Huaqing , Wang, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
electro-migration, [SDU]Sciences of the Universe [physics], electro-osmotic flow, electric potential, electrokinetic remediation, electro-osmotic permeability, [ SDU ] Sciences of the Universe [physics]
Abstract

(IF 3.19; Q1); International audience; Citric acid (CA), a widely used eco-friendly electrolyte, can be employed as an agent for enhancing toxic metal (TM) removal from contaminated dredged sediment using electrokinetic (EK) technology. In this study, dredged harbor sediments co-contaminated by TMs were subjected to enhanced EK treatment using a mixture of chelating agent (CA) and surfactant as an additive in the processing fluids. Several control conditions that may influence the efficiency of TM removal were tested, including open/closed sediment chamber orifices, electric potential gradients (0.5, 1.0, and 1.5 V cm-1), and electrolyte surfactant. Tween 20 (4 mmol L-1) was used as a surfactant within the electrolyte to investigate the extent of TM removal in sediment with high organic matter content. The results showed that an open orifice led to a greater electro-osmotic flow (EOF) with moderate TM removal. In contrast, a closed orifice with a nonionic surfactant electrolyte allowed the highest removal of TMs from the matrix. Moreover, increasing the electric potential gradient led to a higher EOF under the open orifice condition, but no significant increase in TM removal was observed owing to a higher accumulation of TMs in the middle of the matrix, caused by the opposite direction of EOF and electro-migration of metal-citrate complexes.

Published
2018

2. Nonlinear Waves and Pattern Dynamics

Author

Yury Stepanyants, Mikhail I. Rabinovich, Efim Pelinovsky, Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Institute of Applied Physics of RAS, Russian Academy of Sciences [Moscow] ( RAS ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Russian Academy of Sciences [Moscow] (RAS), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
[ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]
Abstract

International audience; This book addresses the fascinating phenomena associated with nonlinear waves and spatio-temporal patterns. These appear almost everywhere in nature from sand bed forms to brain patterns, and yet their understanding still presents fundamental scientific challenges. The reader will learn here, in particular, about the current state-of-the art and new results in:- Nonlinear water waves: resonance, solitons, focusing, Bose-Einstein condensation, as well as and their relevance for the sea environment (sea-wind interaction, sand bed forms, fiber clustering)- Pattern formation in non-equilibrium media: soap films, chimera patterns in oscillating media, viscoelastic Couette-Taylor flow, flow in the wake behind a heated cylinder, other pattern formation. The editors and authors dedicate this book to the memory of Alexander Ezersky, Professor of Fluid Mechanics at the University of Caen Normandie (France) from September 2007 to July 2016. Before 2007, he had served as a Senior Scientist at the Institute of Applied Physics of the Russian Academy of Sciences in Nizhny Novgorod (Russia). The chapters have been written by leading scientists in Nonlinear Physics, and the topics chosen so as to cover all the fields to which Prof. Ezersky himself contributed, by means of experimental, theoretical and numerical approaches.The volume will appeal to advanced students and researchers studying nonlinear waves and pattern dynamics, as well as other scientists interested in their applications in various natural media.

Published
2018

3. Numerical simulation of circular Couette flow under a radial thermo-electric body force

Author

Harunori Yoshikawa, Antoine Meyer, Innocent Mutabazi, Changwoo Kang, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Jean Alexandre Dieudonné ( JAD ), Université Nice Sophia Antipolis ( UNS ), Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Fluid Flow and Transfer Processes, Body force, Centrifugal force, Physics, Mechanical Engineering, Taylor–Couette flow, Computational Mechanics, Liquid dielectric, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Mechanics, Rayleigh number, Condensed Matter Physics, 01 natural sciences, 010305 fluids & plasmas, Physics::Fluid Dynamics, Mechanics of Materials, 0103 physical sciences, Electrohydrodynamics, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], 010306 general physics, Couette flow, Taylor number, ComputingMilieux_MISCELLANEOUS
Abstract

The transition from circular Couette flow of a dielectric fluid with a radial temperature gradient and an alternating electric voltage has been investigated by a direct numerical simulation. The inner cylinder is rotating while the outer one is fixed. The radial temperature gradient and the electric voltage acting on a dielectric fluid generate a radial dielectrophoretic (DEP) force which can induce thermal convection. The flow is controlled by the Taylor number Ta that measures the intensity of the centrifugal force and the electric Rayleigh number L that indicates the intensity of the DEP force. For each value of L, the instability threshold (Tac) is determined and compared with that predicted by the linear stability analysis. Nonlinear coefficients of the Landau equation are computed to reveal the nature of the transition: oscillatory axisymmetric modes occur via a subcritical transition, while steady axisymmetric and oscillatory non-axisymmetric modes occur via supercritical bifurcations. The momentum...

Published
2017

4. Multi-scale analysis of a viscoelastic liquid jet

Author

Christophe Dumouchel, Innocent Mutabazi, Marie-Charlotte Renoult, Olivier Crumeyrolle, Christophe Tirel, Denis Lisiecki, Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Complexe de recherche interprofessionnel en aérothermochimie ( CORIA ), Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences appliquées Rouen Normandie ( INSA Rouen Normandie ), Normandie Université ( NU ) -Normandie Université ( NU ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), and Normandie Université ( NU ) -Normandie Université ( NU )

Subjects
Materials science, Liquid jet, Applied Mathematics, Mechanical Engineering, General Chemical Engineering, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Perturbation (astronomy), Mechanics, Condensed Matter Physics, Breakup, 01 natural sciences, Viscoelasticity, 010305 fluids & plasmas, Exponential function, Condensed Matter::Soft Condensed Matter, Physics::Fluid Dynamics, Classical mechanics, Rheology, 0103 physical sciences, General Materials Science, Viscoelastic Solutions, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], 010306 general physics, Body orifice
Abstract

WOS:000403628200001; International audience; A multi-scale analyzing tool is now available to investigate the temporal evolution of two phase flows such as liquid systems experiencing an atomization process. Thanks to its multi-scale and global nature, it allows identifying all dynamics simultaneously involved in the process with no restriction of the liquid system shape. In the present work this multi-scale tool is applied on 2D visualizations of free falling jets of a low-viscosity viscoelastic solution. The jets are produced from a cylindrical discharge orifice and the liquid is a very dilute polymer solution containing 5 ppm of Poly(ethylene oxide). High spatial resolution images of the free falling jets are performed as a function of the velocity and at several distances from the discharge orifice. For every operating condition, the liquid jet remains cylindrical first, then shows the development of a sinusoidal perturbation and finally adopts a beads-on-a-string pattern before breakup occurs. The multi-scale analysis is performed on a high number of images and at several spatial positions in order to return statistical and temporal information, respectively. The results of this analysis show that during the sinusoidal perturbation stage, the large-scale region follows an exponential increase as predicted by the linear stability theory and during the beads-on-a-string stage, the small-scale region follows an exponential decrease similar to an elasto-capillary regime from which the relaxation time of the polymer solution can be extracted. This work positions the multi-scale approach as a promising and complementary tool to the currently used techniques in order to probe complex liquid rheology, especially in the case of mobile viscoelastic solutions. (C) 2017 Elsevier B.V. All rights reserved.

Published
2017

5. Growth rate measurement in free jet experiments

Author

Innocent Mutabazi, Marie-Charlotte Renoult, Olivier Crumeyrolle, Jean-Baptiste Charpentier, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Complexe de recherche interprofessionnel en aérothermochimie ( CORIA ), Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences appliquées Rouen Normandie ( INSA Rouen Normandie ), Normandie Université ( NU ) -Normandie Université ( NU ) -Université de Rouen Normandie ( UNIROUEN ), and Normandie Université ( NU )

Subjects
Capillary action, Computational Mechanics, General Physics and Astronomy, 02 engineering and technology, 01 natural sciences, Standard deviation, Viscoelasticity, 010305 fluids & plasmas, Physics::Fluid Dynamics, symbols.namesake, 0103 physical sciences, Newtonian fluid, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Rayleigh scattering, Fluid Flow and Transfer Processes, Physics, Jet (fluid), [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Mechanics, 021001 nanoscience & nanotechnology, Amplitude, Classical mechanics, Mechanics of Materials, symbols, 0210 nano-technology, Body orifice
Abstract

WOS:000404657500014; International audience; An experimental method was developed to measure the growth rate of the capillary instability for free liquid jets. The method uses a standard shadow-graph imaging technique to visualize a jet, produced by extruding a liquid through a circular orifice, and a statistical analysis of the entire jet. The analysis relies on the computation of the standard deviation of a set of jet profiles, obtained in the same experimental conditions. The principle and robustness of the method are illustrated with a set of emulated jet profiles. The method is also applied to free falling jet experiments conducted for various Weber numbers and two low-viscosity solutions: a Newtonian and a viscoelastic one. Growth rate measurements are found in good agreement with linear stability theory in the Rayleigh's regime, as expected from previous studies. In addition, the standard deviation curve is used to obtain an indirect measurement of the initial perturbation amplitude and to identify beads on a string structure on the jet. This last result serves to demonstrate the capability of the present technique to explore in the future the dynamics of viscoelastic liquid jets.

Published
2017

6. Radial buoyancy effects on momentum and heat transfer in a circular Couette flow

Author

Changwoo Kang, Innocent Mutabazi, Antoine Meyer, Harunori Yoshikawa, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Jean Alexandre Dieudonné ( JAD ), Université Nice Sophia Antipolis ( UNS ), Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), PEPS-PTI OndInterGE, ANR-10-LABX-09-01,LABEX EMC3, ANR-13-BS09-0025,TRANSFLOW,Transition à la turbulence dans les écoulements cisaillées : théorie, simulation et expérience ( 2013 ), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), ANR-10-LABX-0009,EMC3,Energy Materials and Clean Combustion Center(2010), and ANR-13-BS09-0025,TRANSFLOW,Transition à la turbulence dans les écoulements cisaillées : théorie, simulation et expérience(2013)

Subjects
Fluid Flow and Transfer Processes, Physics, Angular momentum, Buoyancy, Prandtl number, Taylor–Couette flow, Computational Mechanics, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Mechanics, engineering.material, Gravitational acceleration, 01 natural sciences, 010305 fluids & plasmas, Physics::Fluid Dynamics, symbols.namesake, Modeling and Simulation, 0103 physical sciences, Heat transfer, symbols, Annulus (firestop), engineering, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Astrophysics::Earth and Planetary Astrophysics, 010306 general physics, Couette flow
Abstract

International audience; The numerical investigation of a circular Couette flow with a radial temperature gradient is performed to elucidate the influence of the radial buoyancy on flow and heat transfer for different values of the Prandtl number when the gravitational acceleration is neglected. We consider an infinite-length cylindrical annulus of radius ratio 0.8 with the inner rotating cylinder and the outer stationary cylinder. The flow is stabilized with the outward heating while it is destabilized with the inward heating. A weakly nonlinear analysis shows that the transition to stationary axisymmetric modes is supercritical while the oscillatory axisymmetric modes occur via a subcritical bifurcation. The effect of the centrifugal buoyancy on the transfer of angular momentum (i.e., torque) is quite weak while the effect on the heat transfer is significant.

Published
2017

7. Proof of Concept for an Ultrasensitive Technique to Detect and Localize Sources of Elastic Nonlinearity Using Phononic Crystals

Author

Antonio Gliozzi, Bruno Morvan, Marco Scalerandi, Federico Bosia, Nicola M. Pugno, Anastasiia Krushynska, Marco Miniaci, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Damage detection, business.industry, General Physics and Astronomy, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, [PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], Nonlinear system, Physics and Astronomy (all), Optics, Proof of concept, Harmonics, 0103 physical sciences, Acoustic metamaterials, [ PHYS.PHYS.PHYS-GEN-PH ] Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010306 general physics, 0210 nano-technology, business, Elastic wave propagation, Realization (systems), [ PHYS.PHYS.PHYS-INS-DET ] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Digital signal processing
Abstract

The appearance of nonlinear effects in elastic wave propagation is one of the most reliable and sensitive indicators of the onset of material damage. However, these effects are usually very small and can be detected only using cumbersome digital signal processing techniques. Here, we propose and experimentally validate an alternative approach, using the filtering and focusing properties of elastic metamaterials to naturally select the higher harmonics generated by nonlinear effects and to increase their signal-to noise ratios, enabling the realization of time-reversal procedures for nonlinear elastic source detection. The proposed device demonstrates its potential as an efficient, compact, portable, passive apparatus for nonlinear elastic wave sensing and damage detection.

Published
2017

8. Dissociative recombination and vibrational excitation of BF+ in low energy electron collisions

Author

I. F. Schneider, S. Niyonzima, Nicolina Pop, J. Zs. Mezei, Olivier Dulieu, Ousmanou Motapon, Arnaud Bultel, Maxence Lepers, Khaled Hassouni, S. Ilie, Jonathan Tennyson, Kalyan Chakrabarti, F. Colboc, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Laboratoire Aimé Cotton (LAC), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-École normale supérieure - Cachan (ENS Cachan), University of Debrecen, Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), Politehnica University of Timisoara (UPT), University of Burundi, Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Centre for Atomic Molecular Physics and Quantum Optic [Douala] (CEPAMOQ), Université de Douala, Department of Physics and Astronomy [UCL London], University College of London [London] (UCL), Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), Laboratoire Aimé Cotton ( LAC ), École normale supérieure - Cachan ( ENS Cachan ) -Université Paris-Sud - Paris 11 ( UP11 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire des Sciences des Procédés et des Matériaux ( LSPM ), Université Paris 13 ( UP13 ) -Université Sorbonne Paris Cité ( USPC ) -Institut Galilée-Centre National de la Recherche Scientifique ( CNRS ), Politehnica University of Timisoara ( UPT ), Politehnica University of Timisoara, Complexe de recherche interprofessionnel en aérothermochimie ( CORIA ), Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences appliquées Rouen Normandie ( INSA Rouen Normandie ), Normandie Université ( NU ) -Normandie Université ( NU ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ), CEPAMOQ, and University College of London [London] ( UCL )

Subjects
Chemistry, Kinetics, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], 02 engineering and technology, Electron, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Potential energy, Quantum defect, Low energy, Fragmentation (mass spectrometry), 0103 physical sciences, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Atomic physics, 010306 general physics, 0210 nano-technology, Dissociative recombination, Excitation
Abstract

WOS:000385494000003; International audience; The latest molecular data-potential energy curves and Rydberg-valence interactions-characterising the super-excited electronic states of BF are reviewed in order to provide the input for the study of their fragmentation dynamics. Starting from this input, the main paths and mechanisms of BF+ dissociative recombination and vibrational excitation are analysed. Their cross sections are computed for the first time using a method based on the multichannel quantum defect theory (MQDT), and Maxwellian rate-coefficients are calculated and displayed in ready-to-be-used format for low temperature plasma kinetics simulations.

Published
2016

9. Parameterization of wind turbine impacts on hydrodynamics and sediment transport

Author

Vanessa Magar, Anne-Claire Bennis, Aurélie Rivier, Grégory Pinon, Markus Gross, Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Departamento de Oceanografia Fisica CICESE [Mexico], Centro de Investigacion Cientifica y de Education Superior de Ensenada [Mexico] (CICESE), Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), and Centro de Investigacion Cientifica y de Education Superior de Ensenada [Mexico] ( CICESE )

Subjects
010504 meteorology & atmospheric sciences, 020209 energy, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 02 engineering and technology, Oceanography, 01 natural sciences, 0202 electrical engineering, electronic engineering, information engineering, Geotechnical engineering, Foundation, 14. Life underwater, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Marine renewable energy, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, [ SDU.STU.OC ] Sciences of the Universe [physics]/Earth Sciences/Oceanography, Turbulence, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Sediment, [ SDU.STU ] Sciences of the Universe [physics]/Earth Sciences, Sediment transport, Current (stream), Offshore wind power, Drag, Numerical modelling, Offshore wind farms, Erosion, Hydrodynamics, Environmental science, Submarine pipeline
Abstract

(IF 1.60; Q3); International audience; Monopile foundations of offshore wind turbines modify the hydrodynamics and sediment transport at local and regional scales. The aim of this work is to assess these modifications and to parameterize them in a regional model. In the present study, this is achieved through a regional circulation model, coupled with a sediment transport module, using two approaches. One approach is to explicitly model the monopiles in the mesh as dry cells, and the other is to parameterize them by adding a drag force term to the momentum and turbulence equations. Idealised cases are run using hydrodynamical conditions and sediment grain sizes typical from the area located off Courseulles-sur-Mer (Normandy, France), where an offshore windfarm is under planning, to assess the capacity of the model to reproduce the effect of the monopile on the environment. Then, the model is applied to a real configuration on an area including the future offshore windfarm of Courseulles-sur-Mer. Four monopiles are represented in the model using both approaches, and modifications of the hydrodynamics and sediment transport are assessed over a tidal cycle. In relation Responsible Editor: Bruno Castelle Aurélie Rivier to local hydrodynamic effects, it is observed that currents increase at the side of the monopile and decrease in front of and downstream of the monopile. In relation to sediment transport effect, the results show that resuspension and erosion occur around the monopile in locations where the current speed increases due to the monopile presence, and sediments deposit downstream where the bed shear stress is lower. During the tidal cycle, wakes downstream of the monopile reach the following monopile and modify the velocity magnitude and suspended sediment concentration patterns around the second monopile.

Published
2016

10. Defect-mediated turbulence in ribbons of viscoelastic Taylor-Couette flow

Author

Nizar Abcha, Olivier Crumeyrolle, Innocent Mutabazi, Noureddine Latrache, Institut de Recherche Dupuy de Lôme ( IRDL ), Université de Bretagne Sud ( UBS ) -Université de Brest ( UBO ) -ENSTA Bretagne-Centre National de la Recherche Scientifique ( CNRS ), Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de Recherche Dupuy de Lôme (IRDL), Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Université de Bretagne Sud (UBS), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
Materials science, [ SDU.STU.OC ] Sciences of the Universe [physics]/Earth Sciences/Oceanography, Turbulence, Taylor–Couette flow, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Geometry, Mechanics, 01 natural sciences, Viscoelasticity, 010305 fluids & plasmas, Physics::Fluid Dynamics, 0103 physical sciences, Ribbon, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], sense organs, Elasticity (economics), 010306 general physics, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography
Abstract

(IF 2.37; Q1); International audience; Transition to defect-mediated turbulence in the ribbon patterns observed in a viscoelastic Taylor-Couette flow is investigated when the rotation rate of the inner cylinder is increased while the outer cylinder is fixed. In four polymer solutions with different values of the elasticity number, the defects appear just above the onset of the ribbon pattern and trigger the appearance of disordered oscillations when the rotation rate is increased. The flow structure around the defects is determined and the statistical properties of these defects are analyzed in the framework of the complex Ginzburg-Landau equation.

Published
2016

11. Dual-wavelength digital holography for 3D particle image velocimetry: experimental validation

Author

Sébastien Coëtmellec, D. Allano, Denis Lebrun, M. Brunel, Frédéric Corbin, Stanislas Grare, Gérard Gréhan, Gaële Perret, Complexe de recherche interprofessionnel en aérothermochimie ( CORIA ), Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences appliquées Rouen Normandie ( INSA Rouen Normandie ), Normandie Université ( NU ) -Normandie Université ( NU ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
Materials Science (miscellaneous), Holography, 02 engineering and technology, Iterative reconstruction, 01 natural sciences, Industrial and Manufacturing Engineering, law.invention, 010309 optics, Optics, Particle tracking velocimetry, law, 0103 physical sciences, Superimposition, Business and International Management, ComputingMilieux_MISCELLANEOUS, Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], business.industry, Velocimetry, 021001 nanoscience & nanotechnology, Wavelength, Particle image velocimetry, [ SPI.OPTI ] Engineering Sciences [physics]/Optics / Photonic, 0210 nano-technology, business, Digital holography
Abstract

A multi-exposure digital in-line hologram of a particle field is recorded by two successive pulses of different wavelengths. During the reconstruction step, each recording can be independently analyzed by selecting a given wavelength. This procedure enables avoiding the superimposition of particle images that may be close to each other.

Published
2016

12. Digital in-line Holography for Particle Diagnostics in Flows

Author

Lebrun, Denis, Coëtmellec, Sébastien, Brunel, Marc, Perret, Gaële, Lebon, Benoît, Gréhan, Gérard, lebrun, denis, Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Complexe de recherche interprofessionnel en aérothermochimie ( CORIA ), Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences appliquées Rouen Normandie ( INSA Rouen Normandie ), Normandie Université ( NU ) -Normandie Université ( NU ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), and Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
[SPI.OPTI] Engineering Sciences [physics]/Optics / Photonic, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, [ SPI.OPTI ] Engineering Sciences [physics]/Optics / Photonic, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

13. Collisional excitation of C2H- by H2: New interaction potential and scattering calculations

Author

Fabien Dumouchel, Ernesto Quintas-Sánchez, Christian Balança, Richard Dawes, François Lique, Nicole Feautrier, Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Missouri University of Science and Technology (Missouri S&T), University of Missouri System, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique et Atmosphères = Laboratory for Studies of Radiation and Matter in Astrophysics and Atmospheres (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), This work was supported by the CNRS programs 'Physique et Chimie du Milieu Interstellaire (PCMI)' co-funded by the 'Centre National d’Etudes Spatiales (CNES)' and 'Programme National de Physique Stellaire (PNPS)'. Part of the calculation was performed using HPC resources from GENCI-[CINES/IDRIS] (Grant No. 2010040883) and workstations at the 'Centre Informatique' of Paris Observatory. This work was also granted access to the HPC resources of MesoPSL financed by the 'Région Île de France' and the project Equip@Meso (Reference No. ANR-10-EQPX-29-01) of the 'Programme Investissements d’Avenir' supervised by the 'Agence Nationale pour la Recherche'. R.D. and E.Q.-S. were supported by the U.S. Department of Energy (Award No. DE-SC0019740). Computing resources were supported by the National Science Foundation under Grant No. OAC-1919789., and ANR-10-EQPX-0029,EQUIP@MESO,Equipement d'excellence de calcul intensif de Mesocentres coordonnés - Tremplin vers le calcul petaflopique et l'exascale(2010)

Subjects
[PHYS]Physics [physics], General Physics and Astronomy, Atomic and molecular collisions, Physical and Theoretical Chemistry, Quantum dynamics, Molecular physics
Abstract

International audience; Interstellar anions play an important role in astrochemistry as being tracers of the physical and chemical conditions in cold molecular clouds and circumstellar gas. The local thermodynamic equilibrium is generally not fulfilled in media where anions are detected and radiative and collisional data are required to model the observed lines. The C2H- anion has not yet been detected in the interstellar medium; however, collisional data could be used for non-LTE models that would help in identifying the most intense lines. For this purpose, we have computed the first 4D potential energy surface (PES) of the C2H--H2 complex using an explicitly correlated coupled-cluster approach. The PES is characterized by a single deep minimum with a well-depth of 924.96 cm-1. From this interaction potential, we derived excitation cross sections and rate coefficients of C2H- induced by collisions with para- and ortho-H2. The results obtained for collisions with para-H2 are compared to previous calculations performed using a 2D-PES obtained from an average over H2 rotations.

Published
2023

14. Collisional excitation of interstellar molecules: towards the constraint of physical conditions of star-forming regions Non-LTE modelling of cyanopolyynes

Author

Bop, Cheikh T, Lique, François, Faure, A, Dawes, Richard, Quintas-Sánchez, Ernesto, Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Department of Chemistry, Missouri University of Science and Technology, 142 Schrenk Hall, 400 West 11th Street, Rolla, Missouri 65409, United States, Missouri University of Science and Technology (Missouri S&T), University of Missouri System-University of Missouri System, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), African Astronomical Society, and Bop, Cheikh

Subjects
[PHYS.PHYS.PHYS-COMP-PH]Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [PHYS.PHYS]Physics [physics]/Physics [physics], [PHYS.PHYS.PHYS-COMP-PH] Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph], [PHYS.PHYS] Physics [physics]/Physics [physics], Atomic and molecular collisions, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], [SDU.ASTR] Sciences of the Universe [physics]/Astrophysics [astro-ph], Molecular physics, [PHYS.PHYS.PHYS-CHEM-PH] Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract

International audience

Published
2023

15. Bedload transport for heterogeneous sediments

Author

R. Lafite, Sophie Le Bot, Marine Durafour, Armelle Jarno, François Marin, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], [ SDU.OCEAN ] Sciences of the Universe [physics]/Ocean, Atmosphere, 010504 meteorology & atmospheric sciences, Sediment mixtures, 0207 environmental engineering, Soil science, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], 02 engineering and technology, Coastal zone, 01 natural sciences, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Tidal cycle, Bedload transport, [ PHYS.PHYS.PHYS-GEO-PH ] Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], [ SDU.ENVI ] Sciences of the Universe [physics]/Continental interfaces, environment, Environmental Chemistry, 14. Life underwater, 020701 environmental engineering, Dispersion (water waves), [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Grain shape, 0105 earth and related environmental sciences, Water Science and Technology, Bed load, Hydrology, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Hydrogeology, In situ measurements, Homogeneous, [ SPI.MECA.MEFL ] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Particle, [ PHYS.PHYS.PHYS-FLU-DYN ] Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], Geology
Abstract

International audience; A large panel of instruments was deployed in the Eastern English Channel to measure the evolution of bedload fluxes during a tidal cycle for two different sites. The first one was characterized by a sandy bed with a low dispersion in size while the other study site implied graded sediments with grain sizes ranging from fine sands to granules. The in situ results obtained were compared with predictions of total bedload fluxes by classical models. A good agreement was found for homogeneous sediments with these formulas. In the case of size heterogeneous sediments, a fractionwise approach, involving a hiding-exposure coefficient and a hindrance factor, provided better predictions of bedload fluxes, but still some discrepancies were noticed. Present results revealed that the consideration of particle shape in formulas through the circularity index enhanced the estimations of bedload transport rates. A new adjustment of Wu et al.’s (J Hydraul Res 38:427–434, 2000) formula was proposed and a very good agreement was obtained between the measured and predicted values.

Published
2015

16. STABILITY OF A CIRCULAR COUETTE FLOW UNDER RADIAL THERMAL BODY FORCES

Author

Yoshikawa , Harunori, Mayer , Antoine, Crumeyrolle , Olivier, Mutabazi , Innocent, Laboratoire Jean Alexandre Dieudonné ( JAD ), Université Nice Sophia Antipolis ( UNS ), Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), Laurette Tuckerman, José Eduardo Wesfreid, Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
Physics::Fluid Dynamics, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]
Abstract

International audience; A stability analysis of a circular Couette flow of a dielectric fluid subjected to a temperature gradient and an electric field, reveals the generation of internal waves associated with the thermal stratifications of the density and the electric permittivity (Taylor-Couette flow, Electrohydrodynamics). Convective flows and stratified shear flows in a central gravity field are of primary importance in geo-and astrophysics. Realization of laboratory experiments with an artificial radial gravity is regarded as a key to advance the understanding of these flows. Some attempts have been made with an electric effective gravity in annular and spherical geometries [1]. This electric gravity g e originates from the thermal variation of the fluid polarizability: The decrease of the fluid electric permittivity with the temperature yields a thermal Archimedean buoyancy force f e = −αρθg e in an electric field E, where g e = ee ref ∇E 2 /2αρ (α: the coefficient of thermal expansion, ρ: the density, θ: the temperature deviation from a reference one, e: the coefficient of thermal variation of the permittivity, ref : the permittivity at the reference temperature). We perform a theoretical investigation on the stability of a circular Couette flow in the radial electric gravity field under microgravity conditions. The considered system is an annular capacitor of infinite length with the gap filled by a dielectric fluid (Fig.1a). The temperatures of the inner and outer electrodes are maintained constant at T 1 and T 2 , respectively. An electric tension is applied between the electrode, producing a centripetal electric gravity (−g E e r with g E > 0) in the fluid. We model this flow system in the Boussinesq approximation, but with taking into account the centrifugal buoyancy f c = −αρθg c arising from the density stratification in the centrifugal acceleration field (g c = v 2 e r /r). Primary control parameters of the flow are the Taylor number Ta = (R 1 Ωd/ν) d/R 1 and the electric Rayleigh number L = α∆θg E d 3 /νκ, where ν and κ are the kinematic viscosity and thermal diffusivity of the fluid, d = R 2 − R 1 and ∆θ = T 1 − T 2. When the inner cylinder is stationary (Ta = 0), thermal convection develops beyond a critical electric Rayleigh number in outward heating (∆θ > 0) [2]. When the inner cylinder rotates, a classical circular Couette flow is established at small Ta and L. This flow is destabilized at a critical value Ta c of the Taylor number, which depends on L. The linear stability analysis accompanied by detailed examination of critical modes reveals different dynamical regimes (Fig.1b). It is found that, in the regimes where the net effect of the two radial thermal forces, f e and f c , is stabilizing, the critical modes are oscillatory. The frequency of these oscillatory modes is scaled by the buoyancy frequency N based on the radial acceleration field g e + g c. This finding suggests the generation of internal waves through a resonant mechanism inside the Couette flow.

Published
2015

17. Linear stability analysis of a cylindrical annulus under a radial dielectrophoretic body force

Author

Meyer, Antoine, Vadim, Travnikov, Yoshikawa, Harunori, Mutabazi, Innocent, Crumeyrolle, Olivier, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), Laboratoire Jean Alexandre Dieudonné ( JAD ), Université Nice Sophia Antipolis ( UNS ), and Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
[ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

18. Wave generation in a circular Couette flow in thermoelectric radial buoyancy

Author

Yoshikawa, Harunori, Meyer, Antoine, Crumeyrolle, Olivier, Mutabazi, Innocent, Laboratoire Jean Alexandre Dieudonné ( JAD ), Université Nice Sophia Antipolis ( UNS ), Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), PEPS PTI 2014 OndInterGe, ANR-10-LABX-09-01,LABEX EMC3, Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), and ANR-10-LABX-0009,EMC3,Energy Materials and Clean Combustion Center(2010)

Subjects
Physics::Fluid Dynamics, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]
Abstract

International audience; Thermal convection in a centripetal gravity field is of primary importance in geo-and astrophysics , as it is responsible for global-scale heat and mass transport in a planet. Application of a radial electric field to a non isothermal Taylor-Couette system of a dielectric fluid provides a simple analogical system to simulate such convection [1]. Indeed, an electrohydrodynamic force exerted by the electric field can be regarded as thermal buoyancy due to the following radial effective gravity g e : g e = − eΦ 2 0 ρα (log η) 2 F (r, η, e∆T) e r , (ρ: the fluid density, : the fluid electric permittivity, α: the coefficient of thermal expansion, e: the coefficient of thermal variation, Φ 0 : the applied electric tension, ∆T : the temperature difference). The correcting factor F depends on the radial position r, the radius ratio of the inner to outer cylinders η = R 1 /R 2 and the dimensionless parameter e∆T that characterizes the thermal stratification of the fluid permittivity. Under the action of this thermoelectric buoyancy, a temperature difference in the fluid can give rise to the convection [2]. The electric gravity has also potential applications in aerospace engineering, as it can enhance heat transfer by inducing thermal convection under microgravity conditions. We performed a linear perturbation analysis to investigate the development of convective flows in the circular Couette flow under the action of the radial acceleration field g e. The analysis focused to the situation of vanishing Grashof number, i.e., under microgravity conditions , in order to highlight the effects of the electric gravity. The critical parameters, at which the flow lost stability, were determined with varying the Taylor number T a or the Rayleigh number L = α∆T g e (R 2 − R 1) 3 /νκ. Wide ranges of the Prandtl number P r = ν/κ and of the radius ratio η were considered. The different energy transfer processes from the basic to perturbation flows were examined in detail to get insight into instability mechanism.

Published
2015

19. Dissociative recombination and vibrational excitation of CO+: model calculations and comparison with experiment

Author

J. Zs. Mezei, W. Ü. L. Tchang-Brillet, J. Robert, Ioan F. Schneider, Olivier Dulieu, Ousmanou Motapon, Xavier Urbain, Khaled Hassouni, Kalyan Chakrabarti, Vincent Morel, D. E. Tudorache, Arnaud Bultel, R. D. Backodissa-Kiminou, Jonathan Tennyson, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Laboratoire Aimé Cotton (LAC), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-École normale supérieure - Cachan (ENS Cachan), University of Debrecen, Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Centre for Atomic Molecular Physics and Quantum Optic [Douala] (CEPAMOQ), Université de Douala, CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Institut de la matière condensée et des nanosciences / Institute of Condensed Matter and Nanosciences (IMCN), Université Catholique de Louvain = Catholic University of Louvain (UCL), Department of Physics and Astronomy [UCL London], University College of London [London] (UCL), Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), Laboratoire Aimé Cotton ( LAC ), École normale supérieure - Cachan ( ENS Cachan ) -Université Paris-Sud - Paris 11 ( UP11 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire des Sciences des Procédés et des Matériaux ( LSPM ), Université Paris 13 ( UP13 ) -Université Sorbonne Paris Cité ( USPC ) -Institut Galilée-Centre National de la Recherche Scientifique ( CNRS ), CEPAMOQ, CHU Pitié-Salpêtrière [APHP], Complexe de recherche interprofessionnel en aérothermochimie ( CORIA ), Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences appliquées Rouen Normandie ( INSA Rouen Normandie ), Normandie Université ( NU ) -Normandie Université ( NU ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ), Institut de la matière condensée et des nanosciences / Institute of Condensed Matter and Nanosciences ( IMCN ), Université Catholique de Louvain ( UCL ), University College of London [London] ( UCL ), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Cachan (ENS Cachan)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), and Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)

Subjects
Valence (chemistry), Chemistry, Condensed Matter Physics, Potential energy, Quantum defect, symbols.namesake, [SPI]Engineering Sciences [physics], Excited state, Rydberg formula, symbols, [ SPI ] Engineering Sciences [physics], Atomic physics, Electron ionization, Dissociative recombination, Excitation
Abstract

The latest molecular data—potential energy curves and Rydberg/valence interactions—characterizing the super-excited electronic states of CO are reviewed, in order to provide inputs for the study of their fragmentation dynamics. Starting from this input, the main paths and mechanisms for CO+ dissociative recombination are analyzed; its cross sections are computed using a method based on multichannel quantum defect theory. Convoluted cross sections, giving both isotropic and anisotropic Maxwellian rate coefficients, are compared with merged-beam and storage-ring xperimental results. The calculated cross sections underestimate the measured ones by a factor of two, but display a very similar resonant shape. These facts confirm the quality of our approach for the dynamics, and call for more accurate and more extensive molecular structure calculations. Keywords: dissociative recombination, electron impact vibrational excitation, vibrationally excited, multichannel quantum defect theory (Some figures may appear in colour only in the online journal)

Published
2015

20. Regional numerical modelling of offshore monopile wind turbine impacts on hydrodynamics and sediment transport

Author

Rivier, A., Bennis, A. C., Gregory Pinon, Gross, M., Magar, V., Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Departamento de Oceanografia Fisica CICESE [Mexico], Centro de Investigacion Cientifica y de Education Superior de Ensenada [Mexico] ( CICESE ), Guedes Soares, C., Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), and Centro de Investigacion Cientifica y de Education Superior de Ensenada [Mexico] (CICESE)

Subjects
[ SDU.STU.OC ] Sciences of the Universe [physics]/Earth Sciences/Oceanography, 010504 meteorology & atmospheric sciences, 010505 oceanography, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [ SDU.STU ] Sciences of the Universe [physics]/Earth Sciences, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], 01 natural sciences, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

International audience

Published
2015

21. Effect of the radial buoyancy on a circular Couette flow

Author

Harunori Yoshikawa, Innocent Mutabazi, Antoine Meyer, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), CNES, CPER, ANR-10LABX-09-01, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Jean Alexandre Dieudonné ( JAD ), Université Nice Sophia Antipolis ( UNS ), and Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
Fluid Flow and Transfer Processes, Physics, Buoyancy, Mechanical Engineering, Taylor–Couette flow, Prandtl number, Computational Mechanics, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Mechanics, engineering.material, Condensed Matter Physics, Gravitational acceleration, Inertial wave, Physics::Fluid Dynamics, symbols.namesake, Amplitude, Mechanics of Materials, Instabilities, engineering, symbols, Taylor-Couette flow, Astrophysics::Earth and Planetary Astrophysics, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Stratified flow, Couette flow
Abstract

International audience; The effect of a radial temperature gradient on the stability of a circular Couette flow is investigated when the gravitational acceleration is neglected. The induced radial stratification of the fluid density coupled with the centrifugal acceleration generates radial buoyancy which is centrifugal for inward heating and centripetal for outward heating. This radial buoyancy modifies the Rayleigh discriminant and induces the asymmetry between inward heating and outward heating in flow behavior. The critical modes are axisymmetric and stationary for inward heating while for outward heating, they can be oscillatory axisymmetric or nonaxisymmetric depending on fluid diffusion properties, i.e., on the Prandtl number Pr. The dependence of the critical modes on Pr is explored for different values of the radius ratio of the annulus. The power input of the radial buoyancy is compared with other power terms. The critical frequency of the oscillatory axisymmetric modes is linked to the Brunt-Väisälä frequency due to the density stratification in the radial gravity field induced by the rotation. These modes are associated with inertial waves. The dispersion relation of the oscillatory axisymmetric modes is derived in the vicinity of the critical conditions. A weakly nonlinear amplitude equation with a forcing term is proposed to explain the domination of these axisymmetric oscillatory modes over the stationary centrifugal mode.

Published
2015

22. Bottom Particles Segregation: Experiments and Numerical Simulations Using Non-linear Diffusion Equation

Author

Tien Dat Chu, François Marin, Armelle Jarno-Druaux, Djillali Tiguercha, Anne-Claire Bennis, Ezersky, Alexander B., Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), and Weill, Pierre

Subjects
[ SDU.STU.OC ] Sciences of the Universe [physics]/Earth Sciences/Oceanography, sea bottom, Segregation, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [ SDU.STU ] Sciences of the Universe [physics]/Earth Sciences, [SDU.STU.OC] Sciences of the Universe [physics]/Earth Sciences/Oceanography, [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, surface wave, [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], sand ripples, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, non-linear diffusion equation
Abstract

International audience; We report experimental and theoretical results on segregation of particles in sandy bottom under the action of oscillating velocity field due to surface waves. Experiments were performed in-situ and in wave flume. Segregation in the mixtures of light and heavy particles of the same diameter and small and large particles of the same density was observed. It was found that segregation appears on the background of sand ripples generation in the upper «active» zone of the bottom. The thickness of this zone is proportional to the amplitude of velocity oscillation. The topology of segregation patterns depends on particle size differences, on particle density differences as well as on particle percentage composition in the mixture. It was revealed that small particles with small percentage are concentrated below sandy ripples crest. If percentage composition of small and large particles are approximately equal, the large particles are concentrated below the ripples crests. Light particles quite the «active» zone where concentration of heavy particles increases. To investigate the segregation of particles we use non-linear diffusion equations in the presence of gravity field like it was done recently in paper of Fernandez et al (Physica A, 2003, 327, 94–98). The main idea of this model is to take into account the different sizes and densities of particles using mobility coefficients in diffusion equations for concentration of particles. We extended one dimensional model of Fernandez et al for two dimensional case. Numerical simulations demonstrate good qualitative coincidence with experimental data. In particular, zones with high concentration of small and large particles below ripples crest were obtained in numerical simulations depending on percentage composition of particles. Formation of the layer where the concentration of light particles sufficiently decreases was also found in numerical simulations. Importance of segregation processes for biological and environmental problems is discussed.

Published
2015

23. Thermo-electrohydrodynamic internal waves in annular geometry

Author

Yoshikawa , Harunori, Antoine , Meyer, Crumeyrolle , Olivier, Mutabazi , Innocent, Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), PEPS PTI 2014 (OndInterGe), Laboratoire Jean Alexandre Dieudonné ( JAD ), Université Nice Sophia Antipolis ( UNS ), Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), and Normandie Université ( NU ) -Normandie Université ( NU )

Subjects
[ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014

24. Description des images holographiques de bulles : influence des caractéristiques expérimentales du système d'enregistrement

Author

Grare, Stanislas, Allano, Daniel, Gréhan, Gérard, Coëtmellec, Sébastien, Lebrun, Denis, Lebon, Benoît, Perret, Gaële, Brossard, Jerôme, Complexe de recherche interprofessionnel en aérothermochimie ( CORIA ), Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences appliquées Rouen Normandie ( INSA Rouen Normandie ), Normandie Université ( NU ) -Normandie Université ( NU ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), and Eyraud, Philippe

Subjects
[SPI]Engineering Sciences [physics], Cohérence temporelle, [SPI] Engineering Sciences [physics], Hydrodynamique, [ SPI ] Engineering Sciences [physics], Holographie dans l'axe, Métrologie de bulles
Abstract

International audience; L'holographie numérique de Gabor est utilisée pour caractériser les tourbillons qui se forment au voisinage d'objets immergés. Pour cela, nous étudions les trajectoires de bulles qui se forment à proximité d'une plaque métallique plongée dans un canal à houle. Afin de définir au mieux les traitements numériques à appliquer aux images holographiques, nous modélisons les hologrammes générés dans la configuration expérimentale d'étude (diode laser modulée, caméra CMOS). Nous montrons que les différences observées entre hologrammes expérimentaux et modèle s'expliquent d'une part par les propriétés spectrales de la source d'éclairage, et d'autre part, par l'intégration spatiale des franges sur la surface des éléments photosensibles (pixels). I. CONTEXTE I.1 Etude des tourbillons L'interaction de la houle avec une structure immergée (exemple des mâts d'éoliennes offshore) génère des filaments tourbillonnaires très intenses qui ont un fort impact sur leur environnement proche. Pour étudier cette dynamique, les tourbillons sont reproduits dans le canal à houle du LOMC (10x0,3x0,3m) au Havre. On considère le problème simplifié de l'interaction d'une houle régulière avec une plaque plane horizontale. Une étude réalisée au LOMC a mis en évidence des phénomènes d'éclatement tourbillonnaire qui déstabilisent ces tourbillons et qui sont par essence tridimensionnels. 1 Les traceurs utilisés ici sont des bulles générées par électrolyse d~[30-300µm]. Le suivi des trajectoires 3D de ces bulles s'effectue par holographie numérique « in-line » 2,3 .

Published
2014

25. Detection of kissing bond type defects and evaluation of the bonding quality in metal/adhesive/composite structures by a wavenumber-frequency insensitive SH mode

Author

Latifa Attar, Mounsif Ech Cherif El Kettani, Damien Leduc, Mihai Valentin Predoi, Jocelyne Galy, Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), University Politehnica of Bucharest [Romania] (UPB), Ingénierie des Matériaux Polymères (IMP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), RIN DIADEMAR, and European Project

Subjects
Ultrasonic bond testing, Composite material, Kissing bond defect, Shear horizontal waves, [SPI.MECA.STRU]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Structural mechanics [physics.class-ph], Mechanical Engineering, EMAT, Ultrasonic guided waves, General Materials Science, Condensed Matter Physics, Non-destructive evaluation
Abstract

International audience; This work focuses on the non-destructive evaluation of the bonding quality in different metal/adhesive/composite samples and on the detection of defects simulating a kissing bond, using Shear Horizontal (SH) guided waves. A predictive 2D numerical model, called interphases model and based on finite elements method describing the interface substrate/adhesive by a very thin layer, is developed. Various samples with different adhesion levels obtained by modifying the cohesive and adhesive aspects or including a defect representing a kissing bond are investigated. An experimental study is performed with non-contact ElectroMagnetic Acoustic Transducers (EMAT) in excitation and reception. As the wavenumber-frequency sensitive SH modes to the adhesion quality shown by the numerical predictions are not easy to generate experimentally, the analysis of the behaviour of the SH modes is based here on their amplitude. Results show that it is possible to differentiate between the adhesion levels due to different epoxy conversion, the presence or absence of an adhesion promoter or a pollution by a release agent, as well as the detection of the defect.

Published
2023

26. Towards a numerical modeling of the coupling between RTM process and induced mechanical properties for rigid particle-filled composites

Author

Ahmed El Moumen, Abdelghani Saouab, Abdellatif Imad, Toufik Kanit, Unité de Mécanique de Lille - ULR 7512 (UML), Université de Lille, Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Control and Systems Engineering, Mechanical Engineering, [NLIN]Nonlinear Sciences [physics], Industrial and Manufacturing Engineering, Software, Computer Science Applications
Abstract

In this work, a method is proposed for modeling RTM process and the associated mechanical behavior of composites filled with mono-sized spherical Alumina particles. This method combines (i) a numerical model (RTM model) that allows the simulation of the RTM process during the injection of particle filled resins, and (ii) a computational strategy of mechanical properties based on the homogenization methods. These proposed models have already been validated with experimental results. The RTM model is based on 3 sub-models: the first one to describe the suspension flow, the second one to simulate the advance of the flow front, and the last one to model the particles filtration by the fibrous medium. The distribution result of the concentration of particles in the fibrous medium obtained at the end of the simulation of the injection is used as input data for mechanical models of homogenization. The homogenization numerical model was constructed from a representative volume element of the microstructures using the Poisson process. The idea here is to couple these two steps (RTM simulation + mechanical properties computation) in a complete model which allows at the same time and in a single operation: to simulate the process of the manufactured composites loaded with particles and to deduce their induced mechanical properties. The pertinence of the proposed method is confirmed by the simulation of nine elastic properties of composites with the finite element method. The influence of post-filling on the induced mechanical properties has been studied.

Published
2023

27. Extraction des métaux lourds des sediments par la méthode électrocinétique

Author

Song , Y., Benamar , A., Mezazigh , S., Wang , H., Physics Department and Center for Interdisciplinary Research on Complex Systems, Northeastern University [Boston], Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), RIKEN Nishina Center, RIKEN, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), RIKEN Nishina Center for Accelerator-Based Science [Wako] (RIKEN RNC), RIKEN - Institute of Physical and Chemical Research [Japon] (RIKEN), and Casado-Malaizé, Valérie

Subjects
[SDU] Sciences of the Universe [physics], [SDU]Sciences of the Universe [physics], ComputingMilieux_MISCELLANEOUS, [ SDU ] Sciences of the Universe [physics]
Abstract

International audience

Published
2014

28. Heat transfer by Görtler vortices developed on a wall with finite conductivity

Author

Lyes , Kahouadji, Yoshikawa , Harunori, Peixinho , Jorge, Mutabazi , Innocent, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Investissements d’Avenir (ANR-10-LABX-09-01), LABEX EMC3, E. Falcon, M. Lefranc, F. Pétrélis, C.-T. Pham, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Jean Alexandre Dieudonné ( JAD ), Université Nice Sophia Antipolis ( UNS ), and Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
Physics::Fluid Dynamics, Hydrodynamic instabilities, Heat transfer, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]
Abstract

International audience; Görtler vortices are streamline vortices that appear in a flow over a concave wall as a result of centrifugal instability. They have a strong influence on the heat transfer. The purpose of this study is to model the heat transfer enhancement by those vortices using a weakly nonlinear analysis. Computations of basic state coupled with spatial first and second order perturbations provide this heat transfer enhancement, at the fluid-wall interface, as a function of the Prandtl number, the dimensionless wall thickness and the thermal conductivity ratio between the wall and the fluid.

Published
2014

29. Heat transfer enhancement by the Goetler vortices developed on a wall with a finite thermal conductivity

Author

Mutabazi , Innocent, Yoshikawa , Harunori, Peixinho , Jorge, Lyes , Kahouadji, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), and Yoshikawa, Harunori

Subjects
[ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2013

30. Stability of the Taylor-Couette flow under a radial thermoelectric body force

Author

Yoshikawa, Harunori, Mutabazi, Innocent, Antoine, Meyer, Crumeyrolle, Olivier, Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), Yoshikawa, Harunori, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
[ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2013

31. Comparison of the experimental response of two horizontal axis tidal turbines to wave and current

Author

DUFOUR, Marc-Amaury, Gaurier, Benoît, Pinon, Grégory, Germain, Grégory, Facq, Jean-Valéry, Togneri, Michael, Represas, Fabio, Nicolas, Erwann, Marcille, Julie, Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Laboratoire Comportement des Structures en Mer (LCSM), Recherches et Développements Technologiques (RDT), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), College of Engineering [Swansea], Swansea University, Magallanes Renovables [Redondela, Spain], Sabella, and European Project: EAPA_333/2016,MONITOR

Subjects
Fluctuating loads, Tidal energy converters, Horizontal axis tidal turbine, Wave-current interaction, Blade root loads, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph]
Abstract

International audience; This paper studies wave influence on two horizontal axis tidal turbines from industrial partners : Sabella and Magallanes. The trials have been performed in a wave and current flume tank where upstream flow conditions have been monitored thanks to Laser Doppler Velocimetry. Mean velocity is computed withrotor disc integration of the velocity profile. Wave amplitude and orbital amplitude are computed thanks to least mean square method.A special attention has been paid to turbine immersion depth. Performance and blade root loads analysis highlight higher fluctuations when the turbine is close to the free surface.When a turbine is close to the free surface, the edgewise moment fluctuations can reach 100 % of the mean effort under combined wave and turbulence loading. Wave is responsible for half part of these fluctuations.; Dans ce papier est étudiée expérimentalement l’influence de la houle et du courant combinés sur le comportement de deux hydroliennes à axe horizontal pré-commerciales. Les essais sont réalisés dans un bassin à houle et courant où les conditions d’essais sont obtenues par vélocimétrie laser. La vitesse moyenne de l’écoulement est calculée par intégration sur le disque rotor. Les amplitudes de houle et les orbitales de vague sont déterminées par méthode des moindre carrés.Une attention particulière est apportée sur l’influence de la profondeur d’immersion des turbines. L’analyse des performances et des efforts sur les pales met en évidence une augmentation des fluctuations d’efforts avec la diminution de la profondeur.Le moment de mise en rotation en pied de pale sur une turbine subit des fluctuations allant jusqu’à 100 % de l’effort moyen sous l’effet de la houle et de la turbulence lorsque la turbine est proche de la surface libre. La houle est responsable de la moitié de cette fluctuation.

Published
2022

32. Late Holocene sea-cliff retreat recorded by 10Be profiles across a coastal platform: Theory and examples from the English Channel and Korea

Author

Regard, Vincent, Dewez, Thomas, Bourlès, Didier L., ANDERSON, R.-S., Duperret, Anne, Costa, Stéphane, LEANNI, Laetitia, Pedoja, Kevin, Maillet, Grégoire M., Domaines Océaniques (LDO), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS), Géosciences Environnement Toulouse (GET), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Littoral, Environnement, Télédétection, Géomatique (LETG - Caen), Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Brest (UBO)-École pratique des hautes études (EPHE)-Université de Nantes (UN)-Université d'Angers (UA)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 2 (UR2), Normandie Université (NU)-Normandie Université (NU), Morphodynamique Continentale et Côtière (M2C), Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), Laboratoire 'Paysages & Biodiversité' (PPF DS10), Université d'Angers (UA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université de Nantes (UN)-Université de Nantes (UN)-Université de Caen Normandie (UNICAEN), Université de Nantes (UN)-Université de Nantes (UN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Centre National de la Recherche Scientifique (CNRS)-Institut d'écologie et environnement-Observatoire des Sciences de l'Univers-Université de Brest (UBO)-Institut national des sciences de l'Univers (INSU - CNRS), Domaines Océaniques ( LDO ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Brest ( UBO ) -Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique ( CNRS ), Géosciences Environnement Toulouse ( GET ), Institut de Recherche pour le Développement ( IRD ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Observatoire Midi-Pyrénées ( OMP ) -Centre National de la Recherche Scientifique ( CNRS ), Bureau de Recherches Géologiques et Minières (BRGM) ( BRGM ), Centre européen de recherche et d'enseignement de géosciences de l'environnement ( CEREGE ), Centre National de la Recherche Scientifique ( CNRS ) -Institut de Recherche pour le Développement ( IRD ) -Aix Marseille Université ( AMU ) -Collège de France ( CdF ) -Institut National de la Recherche Agronomique ( INRA ) -Institut national des sciences de l'Univers ( INSU - CNRS ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Littoral, Environnement, Télédétection, Géomatique ( LETG - Caen ), Littoral, Environnement, Télédétection, Géomatique ( LETG ), Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Université d'Angers ( UA ) -Université de Nantes ( UN ) -École pratique des hautes études ( EPHE ) -Université de Brest ( UBO ) -Université de Rennes 2 ( UR2 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Caen Normandie ( UNICAEN ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ), Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), and Université d'Angers ( UA )

Subjects
English Channel, Korea, [SHS.GEO]Humanities and Social Sciences/Geography, ComputingMilieux_MISCELLANEOUS, coastal platform, [ SHS.GEO ] Humanities and Social Sciences/Geography
Abstract

International audience

Published
2013

33. Couette-Taylor flow under a thermoelectric body force in microgravity

Author

Yoshikawa , Harunori, Crumeyrolle , Olivier, Mutabazi , Innocent, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), and Yoshikawa, Harunori

Subjects
Physics::Fluid Dynamics, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]
Abstract

International audience; The Couette-Taylor flow of dielectric fluids is investigated under a radial temperature gradient and a radial high-frequency electric field, where a thermoelectric coupling gives rise to the dielectrophoretic body force on the fluids. The latter force acting in the radial direction can be deemed as thermal buoyancy due to an effective gravity ge. This gravity can provoke a thermal convection even in microgravity, when the Rayleigh number based on ge is larger than a critical value [Yoshikawa et al., Phys. Fluids, 2013, 25:024106]. In the absence of cylinders rotation, the critical mode is stationary and is made of helices [Malik et al., Acta Astronaut. 2012, 81:563–569]. Considering a rotating inner cylinder, we will discuss the competition between this thermoelectric instability and the centrifugal instability. A stability theory accompanied by an energetic analysis will be presented to this aim.

Published
2013

34. Velocity field of the spiral vortex flow in the Couette-Taylor system

Author

Alexander Ezersky, Olivier Crumeyrolle, Nizar Abcha, Innocent Mutabazi, Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Mécanique, Physique et Géosciences (LMPG), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Laboratoire de Mécanique, Physique et Géosciences ( LMPG ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes ( LOMC ), and Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
Physics, [SDE.MCG]Environmental Sciences/Global Changes, Anharmonicity, Taylor–Couette flow, Biophysics, Surfaces and Interfaces, General Chemistry, Mechanics, 01 natural sciences, 010305 fluids & plasmas, Vortex, Physics::Fluid Dynamics, [ SDE.MCG ] Environmental Sciences/Global Changes, Classical mechanics, Particle image velocimetry, Flow (mathematics), 0103 physical sciences, [ SDU.ENVI ] Sciences of the Universe [physics]/Continental interfaces, environment, General Materials Science, Vector field, 010306 general physics, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Couette flow, Spiral, Biotechnology
Abstract

International audience; Spiral vortex flow in the counter-rotating Couette-Taylor system with a large aspect ratio and an intermediate gap has been investigated using Particle Image Velocimetry (PIV). From data of velocity components, we have determined nonlinear properties (anharmonicity, mirror symmetry, axial and radial flow rates) of spiral vortices and compared them to those of Taylor vortices. The velocity field around a spatio-temporal defect has been measured. There is a good agreement between these experimental results with available results from numerical simulations.

Published
2013

35. Dielectrophoretic force-driven thermal convection in annular geometry

Author

Innocent Mutabazi, Harunori Yoshikawa, Olivier Crumeyrolle, Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), CNES, CNRS, Université du Havre, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
[PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], Convection, Buoyancy, Computational Mechanics, Liquid dielectric, engineering.material, 01 natural sciences, Instability, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], 010305 fluids & plasmas, Physics::Fluid Dynamics, 0103 physical sciences, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], 010306 general physics, Fluid Flow and Transfer Processes, Physics, Electrohydrodynamics, Mechanical Engineering, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Radius, Rayleigh number, Mechanics, Condensed Matter Physics, Temperature gradient, Classical mechanics, Mechanics of Materials, Instabilities, engineering, [ SPI.MECA.MEFL ] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], [ PHYS.PHYS.PHYS-FLU-DYN ] Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn]
Abstract

International audience; The thermal convection driven by the dielectrophoretic force is investigated in an- nular geometry under microgravity conditions. A radial temperature gradient and a radial alternating electric field are imposed on a dielectric fluid that fills the gap of two concentric infinite-length cylinders. The resulting dielectric force is regarded as thermal buoyancy with a radial effective gravity. This electric gravity varies in space and may change its sign depending on the temperature gradient and the cylinder radius ratio. The linear stability problem is solved by a spectral-collocation method. The critical mode is stationary and non-axisymmetric. The critical Rayleigh number and wavenumbers depend sensitively on the electric gravity and the radius ratio. The mechanism behind the instability is examined from an energetic viewpoint. The insta- bility in wide gap annuli is an exact analogue to the gravity-driven thermal instability.

Published
2013

36. Dielectrophoretic Rayleigh-Bénard convection under microgravity conditions

Author

Harunori Yoshikawa, Innocent Mutabazi, Olivier Crumeyrolle, M. Tadie Fogaing, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), CNES, Financement européen (FEDER), Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), and Normandie Université ( NU ) -Normandie Université ( NU )

Subjects
Convection, Convective heat transfer, Thermodynamics, 01 natural sciences, 010305 fluids & plasmas, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Physics::Fluid Dynamics, Combined forced and natural convection, 0103 physical sciences, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], 010306 general physics, [NLIN.NLIN-AO]Nonlinear Sciences [physics]/Adaptation and Self-Organizing Systems [nlin.AO], Rayleigh–Bénard convection, Physics, Natural convection, Ginzburg-Landau equation, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Mechanics, Rayleigh number, Heat Transfer, Temperature gradient, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, Instabilities, Heat transfer, [ SPI.MECA.MEFL ] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], [ SPI.ELEC ] Engineering Sciences [physics]/Electromagnetism, [ NLIN.NLIN-AO ] Nonlinear Sciences [physics]/Adaptation and Self-Organizing Systems [nlin.AO]
Abstract

International audience; Thermal convection in a dielectric fluid layer between two parallel plates subjected to an alternating electric field and a temperature gradient is investigated under microgravity conditions. A thermoelectric coupling resulting from the thermal variation of the electric permittivity of the fluid produces the dielectrophoretic (DEP) body force, which can be regarded as thermal buoyancy due to an effective gravity. This electric gravity can destabilize a stationary conductive state of the fluid to develop convection. The similarity of the DEP thermal convection with the Rayleigh-Bénard (RB) convection is examined by considering its behavior in detail by a linear stability theory and a two-dimensional direct numerical simulation. The results are analyzed from an energetic viewpoint and in the framework of the Ginzburg-Landau (GL) equation. The stabilizing effects of a thermoelectric feedback make the critical parameters different from those in the RB instability. The nonuniformity of the electric gravity arising from the finite variation of permittivity also affects the critical parameters. The characteristic constants of the GL equation are comparable with those for the RB convection. The heat transfer in the DEP convection is weaker than in the RB convection as a consequence of the feedback that impedes the convection.

Published
2013

37. DEP thermal convection in annular geometry under microgravity conditions

Author

Yoshikawa , Harunori, Crumeyrolle , Olivier, Mutabazi , Innocent, Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), Yoshikawa, Harunori, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
Physics::Fluid Dynamics, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]
Abstract

International audience; Thermal convection driven by the dielectrophoretic force is investigated in annular geometry in microgravity environments. A radial heating and a radial alternating electric field are imposed on a dielectric fluid layer filling the gap of two concentric infinite-length cylinders. The resulting dielectric force field is regarded as spatially varying radial gravity that can develop thermal convection. The linear stability problem of a purely conductive basic state is solved by a spectral-collocation method for both axisymmetric and non-axisymmetric disturbances. A stationary non-axisymmetric mode becomes first unstable at a critical Rayleigh number to develop convection. The stability boundary shows asymmetry with respect to heating direction. For an outward heating the critical value approaches that of the Rayleigh-Bénard problem (1708) as the gap size decreases, while it converges to larger values in the narrow gap limit. For an inward heating the instability occurs only when the gap is narrower than a certain value. The critical number diverges with increasing the gap size. Instability mechanism is examined from energetic viewpoints. The feedback of electric field to temperature disturbances is found to stabilize the conductive state for narrow gaps.

Published
2012

38. Application of the Particle Image Velocimetry to the Couette-Taylor Flow

Author

Innocent Mutabazi, Nizar Abcha, Alexander Ezersky, Olivier Crumeyrolle, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Turbulence, [SDE.MCG]Environmental Sciences/Global Changes, Mechanics, Laser Doppler velocimetry, Velocimetry, 01 natural sciences, 010305 fluids & plasmas, Physics::Fluid Dynamics, [ SDE.MCG ] Environmental Sciences/Global Changes, Particle image velocimetry, Flow (mathematics), Particle tracking velocimetry, 0103 physical sciences, [ SDU.ENVI ] Sciences of the Universe [physics]/Continental interfaces, environment, Vector field, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, 010306 general physics, Couette flow
Abstract

For longtime, the investigation of flow regimes has been achieved using fluorescent particles or anisotropic reflective particles. Fluorescent particles are suitable for open flows (Van Dyke, 1982) such as flows in channels (Peerhossaini et al., 1988) or flows behind a cylinder (to visualize Benard-von Karman street) (Provansal et al., 1986; Mutabazi et al., 2006). For closed flows such as flows in a rectangular cavity or in an annular cylindrical rotating cavity, fluorescent particles rapidly color the entire flow and no flow structure can be caught. Anisotropic reflective particles (aluminium, iriodin or Kalliroscope flakes) are more convenient for detection of the flow structures (Taylor, 1923; Andereck et al., 1986; Coles, 1965; Matisse et al., 1984; Dominguez-Lerma et al. , 1985; Thoroddsen et al. 1999). A laser light is used to illuminate the flow cross-sections and to detect the flow structure in the axial, radial and azimuthal directions. The motion of the seeded particles in a fluid gives a qualitative picture of flows which can be used to develop appropriate theoretical models. The development of chaotic models of fluid flows (Rayleigh-Benard convection, CouetteTaylor flow or plane Couette flow) has benefited from observations using visualizations techniques (Berge et al., 1994). Using appropriate signal processing techniques such as spacetime diagrams and complex demodulation, it is possible to obtain spatio-temporal evolution of the flows (Bot et al., 2000). In order to obtain quantitative data on velocity fields, different velocimetry techniques have been developed such as Laser Doppler Velocimetry (LDV, Durst et al., 1976, Jensen 2004), Ultrasound Doppler Velocimetry (UDV, Takeda et al., 1994) and Particle Image Velocimetry (PIV, Jensen, 2004). Nowadays, there is a lot of literature on velocimetry techniques the development of which is beyond the scope of this chapter, some of them and their applications are described in this volume. Each velocimetry technique has its advantages and own limitations depending on the flow system under consideration. For example, in the case of the Couette-Taylor flow, the LDV (Ahlers et al., 1986) gives time averaged velocity in a point, the UDV measures a velocity profile along a chosen line in the flow and the PIV gives a velocity field in a limited flow cross section. The Couette-Taylor system is composed of a flow in the gap between two coaxial differential rotating cylinders. This system represents a good hydrodynamic prototype for the study of the transition to turbulence in closed systems. The experimental results obtained from this system have led

Published
2012

39. Thermo-electro-hydrodynamic instabilities in a dielectric liquid under microgravity

Author

Innocent Mutabazi, Satish V. Malik, Harunori Yoshikawa, Olivier Crumeyrolle, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), CNES, Financement européen (FEDER), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), and Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
Chebyshev polynomials, Prandtl number, Liquid dielectric, Aerospace Engineering, Curvature, 01 natural sciences, Instability, 010305 fluids & plasmas, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Physics::Fluid Dynamics, symbols.namesake, 0103 physical sciences, Annulus (firestop), Flow instabilities, Thermal convection, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], 0101 mathematics, Physics, Electrohydrodynamics, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Mechanics, 010101 applied mathematics, Temperature gradient, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, Classical mechanics, symbols, [ SPI.MECA.MEFL ] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], [ SPI.ELEC ] Engineering Sciences [physics]/Electromagnetism, Microgravity, Marginal stability
Abstract

International audience; Linear stability analysis of a dielectric fluid confined in a cylindrical annulus of infinite length is performed under microgravity conditions. A radial temperature gradient and a high alternating electric field imposed over the gap induce an effective gravity that can lead to a thermal convection even in the absence of the terrestrial gravity. The linearized governing equations are discretized using a spectral collocation method on Chebyshev polynomials to compute marginal stability curves and the critical parameters of instability. The critical parameters are independent of the Prandtl number, but they depend on the curvature of the system. The critical modes are non-axisymmetric and are made of stationary helices.

Published
2012

40. Ortho-para-H-2 conversion by hydrogen exchange: Comparison of theory and experiment

Author

Pascal Honvault, Alexandre Faure, François Lique, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU), Laboratoire Interdisciplinaire Carnot de Bourgogne (LICB), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes ( LOMC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ), Laboratoire Interdisciplinaire Carnot de Bourgogne ( LICB ), Université de Bourgogne ( UB ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de Planétologie et d'Astrophysique de Grenoble ( IPAG ), Observatoire des Sciences de l'Univers de Grenoble ( OSUG ), Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Centre National de la Recherche Scientifique ( CNRS ), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), and Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)

Subjects
H-2, Hydrogen exchange, COLLISIONS, Chemistry, SURFACES, GEOMETRIC PHASE, General Physics and Astronomy, ROTATIONAL TRANSITIONS, 01 natural sciences, Chemical reaction, Geometric phase, Excited state, ASTROPHYSICAL MEDIA, 0103 physical sciences, Potential energy surface, EXCITATION, Physical and Theoretical Chemistry, Atomic physics, 010306 general physics, 010303 astronomy & astrophysics, H+H-2 REACTION, Excitation
Abstract

International audience; We report fully-quantum time-independent calculations of cross sections and rate coefficients for the collisional (de) excitation of H-2 by H. Our calculations are based on the H-3 global potential energy surface of Mielke et al. [J. Chem. Phys. 116, 4142 (2002)]. The reactive hydrogen exchange channels are taken into account. We show that the ortho-para and para-ortho conversion of H-2 are significant processes at temperatures above similar to 300 K and for the last process we provide the first comparison with available experimental rate coefficients between 300 and 444 K. The good agreement between theory and experiment is a new illustration of our detailed understanding of the simplest chemical reaction. The importance of the ortho-para-H-2 conversion by hydrogen exchange in astrophysics is discussed.

Published
2012

41. Flow instabilities in a vertical differentially rotating cylindrical annulus with a radial temperature gradient

Author

Mutabazi, Innocent, Guillerm, R., Prigent, A., Lepiller, V., Malik, S., Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Eyraud, Philippe, Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
Data_FILES, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, [ SPI.MECA.MEFL ] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [SPI.MECA.MEFL] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], ComputingMilieux_MISCELLANEOUS, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph]
Abstract

see pdf file

Published
2011

42. Collisional excitation by H2O: the challenge of numerical limitations

Author

Godard Palluet, A, Zoltowski, Michal, Desrousseaux, Benjamin, Lique, François, Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics], [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, [PHYS.PHYS.PHYS-ATM-PH]Physics [physics]/Physics [physics]/Atomic and Molecular Clusters [physics.atm-clus], [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract

International audience; With an operating Atacama Large Millimeter Array telescope and the recently launchedJames Webb Space Telescope, astronomy enters its golden age. Physical conditions of the interstellar medium (ISM) are derived from molecular spectra. The interpretation of these spectra requires to know the population of energy levels of the chemical species. However, most of the astrophysical media do not fulfill local thermodynamic equilibrium conditions. are determined by taking into account both radiative, characterized by Einstein coefficients, and collisonal, characterized by rate coefficients, transitions. Nowadays, the rate coefficients, which are system-specific, can only be computed for ”small” molecules colliding with light partners. However, in media like cometary or planetary atmospheres, the dominant colliders are ”big” molecules, such as H2O, CO, etc. Our understanding of the chemical composition of the universe is limited by computer power. Therefore, numerical strategies need to be elaborated to compute accurate rate coefficients for ”big” collisional systems. In this work, limitations and strategies that can be put into place to treat colliding systems involving H2O will be presented through the example of CS-H2O and HCN-H2O. This study starts by quantum calculations in order to reach convergence for as many transitions as possible. The approaches used are the ”exact” Close-Coupling method, that will be then supported with Coupled-State or infinite order sudden approximations. In a second part, collisional data are computed with statistical methods. The accuracy of the results obtained with the different methods will be evaluated by a comparison with the results obtained with quantum calculations

Published
2022

43. The structure of spatio-temporal defects in a spiral pattern in the Couette-Taylor flow

Author

Alexander Ezersky, Innocent Mutabazi, Nizar Abcha, Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
Physics, [SDE.MCG]Environmental Sciences/Global Changes, Ginzburg landau equation, General Physics and Astronomy, Mechanics, 01 natural sciences, 010305 fluids & plasmas, Flow control (fluid), [ SDE.MCG ] Environmental Sciences/Global Changes, Classical mechanics, Spatio-temporal patterns Defect Couette-Taylor flow Ginzburg-Landau equation, Spiral wave, 0103 physical sciences, [ SDU.ENVI ] Sciences of the Universe [physics]/Continental interfaces, environment, 010306 general physics, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment
Abstract

International audience; Disorder in spiral pattern arising in the counter-rotating Couette-Taylor flow has been investigated. It was revealed that in a certain range of flow control parameters, defects may be generated on the background of spirals periodically in time. Spatio-temporal structure of a single defect has been investigated in detail. A simple theoretical model based on asymptotic solution of the complex Ginzburg-Landau equation was proposed to explain characteristics of a defect. We found that, for a given super-criticality, defects appear at a definite value of the spiral wave phase.

Published
2010

44. Segregation of sedimenting grains of different densities in an oscillating velocity field of strongly nonlinear surface waves

Author

Alexander Ezersky, Marin F, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Morphodynamique Continentale et Côtière ( M2C ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Rouen Normandie ( UNIROUEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
[PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], [ SDU.OCEAN ] Sciences of the Universe [physics]/Ocean, Atmosphere, Materials science, Ripple, Pattern formation, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], 01 natural sciences, 010305 fluids & plasmas, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Physics::Fluid Dynamics, chemistry.chemical_compound, Optics, [ PHYS.PHYS.PHYS-GEO-PH ] Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], 0103 physical sciences, [ SDU.ENVI ] Sciences of the Universe [physics]/Continental interfaces, environment, Paddle, 010306 general physics, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, business.industry, Mechanics, Flume, Polyvinyl chloride, chemistry, [ SPI.MECA.MEFL ] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Vector field, Crest, [ PHYS.PHYS.PHYS-FLU-DYN ] Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], business, Mechanical wave
Abstract

International audience; This paper reports the results of an experimental and theoretical study of the segregation of heavy (sand) and light [polyvinyl chloride (PVC)] grains under the action of intense nonlinear water waves, solitons. The tests are carried out with initially carefully mixed grains at the bottom of a wave flume used in resonant mode. Ripples form on the bed and the segregation process is considered after the stopping of the wave paddle. The waves are damped and the PVC grains concentrate in a narrow region close to the ripple crest. A theoretical model explaining this grain density segregation is developed.

Published
2008

45. Destabilization of inertio-elastic mode via spatiotemporal intermittency in a Couette-Taylor viscoelastic flow

Author

Nizar Abcha, Olivier Crumeyrolle, Innocent Mutabazi, Noureddine Latrache, Laboratoire Ondes et Milieux Complexes ( LOMC ), Université Le Havre Normandie ( ULH ), Normandie Université ( NU ) -Normandie Université ( NU ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Ondes et Milieux Complexes (LOMC), Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)

Subjects
Hopf bifurcation, Physics, History, Turbulence, [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Laminar flow, 01 natural sciences, Instability, Supercritical fluid, 010305 fluids & plasmas, Computer Science Applications, Education, law.invention, Physics::Fluid Dynamics, symbols.namesake, Classical mechanics, Flow (mathematics), law, Intermittency, 0103 physical sciences, symbols, Cylinder, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], 010306 general physics
Abstract

International audience; We have characterized the transition to turbulence in a flow with semi-dilute solutions (concentration of 0.07%) of polyethylene oxide (PEO) in the Couette-Taylor system with rotating only the inner cylinder. The first instability mode occurs via a supercritical Hopf bifurcation in form of interacting right and left spirals. For higher values of the rotation velocity, turbulent spots appear in the flow and coexist with the spirals. This spatio-temporal intermittency (STI) regime has been characterized by the turbulent fraction and the statistical properties of the laminar domains.

Published
2008

46. Rotational excitation of CO2 induced by He: New potential energy surface and scattering calculations

Author

Amélie Godard Palluet, François LIQUE, Franck THIBAULT, Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), and We acknowledge financial support from the European Research Council (Consolidator Grant COLLEXISM, Grant Agreement No. 811363) and the Programme National 'Physique et Chimie du Milieu Interstellaire' (PCMI) of CNRS/INSU with INC/INP co-funded by CEA and CNES. This work was supported by Rennes Metropole.

Subjects
[PHYS]Physics [physics], Complete basis sets, Rate coefficients, General Physics and Astronomy, Potential-energy surfaces, Astrophysics, Rotational excitation, Scattering calculations, Van der Waals forces, Potential energy, Carbon dioxide, Potential energy surfaces, Coupled clusters methods, Collisional, Numerical methods, Atomic and molecular collisions, Physical and Theoretical Chemistry, Quantum dynamics, Molecular physics, Quantum chemistry, Van der Waals complex, Neutral species, Collisional system
Abstract

The CO2 molecule is of great interest for astrophysical studies since it can be found in a large variety of astrophysical media where it interacts with the dominant neutral species, such as He, H2, or H2O. The CO2–He collisional system was intensively studied over the last two decades. However, collisional data appear to be very sensitive to the potential energy surface (PES) quality. Thus, we provide, in this study, a new PES of the CO2–He van der Waals complex calculated with the coupled-cluster method and a complete basis set extrapolation in order to provide rotational rate coefficients that are as accurate as possible. The PES accuracy was tested through the calculations of bound state transition frequencies and pressure broadening coefficients that were compared to experimental data. An excellent agreement was globally found. Then, revised collisional data were provided for the 10–300 K temperature range. Rate coefficients were compared to previously computed ones and are found to be up to 50% greater than previously provided ones. These differences can induce non-negligible consequences for the modeling of CO2 abundance in astrophysical media.

Published
2022

47. Quantifying the yield stress of bentonite muds mixed with other clays during drilling operations

Author

A. Bougouin, A. Pantet, N.-D. Ahfir, Institut universitaire des systèmes thermiques industriels (IUSTI), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Geochemistry and Petrology, [SPI.GCIV.GEOTECH]Engineering Sciences [physics]/Civil Engineering/Géotechnique, Clay, Geology, Binary suspension, Drilling mud, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Rheology, Yield stress
Abstract

International audience; In civil engineering, bentonite-water mixtures, commonly referred to as drilling muds, are intensively used in order to lubricate tools, consolidate walls, and help extracting cuttings during drilling operations. The efficiency of drilling muds in each of these tasks lies in their rheological properties depending mainly on the amount of clay materials. During the field works, drilling muds are mixed with the excavated soil materials (e.g., sand, clay, organic matter) that may change drastically the rheological properties of mixtures. With the aim of understanding better the rheology of field drilling muds mixed with other clays, rheological measurements on monoand binary-clay suspensions were performed using a rotational rheometer equipped with coaxial cylinders, for which the type of clay materials (i.e., bentonite, kaolin and illite), the total clay volume fraction $\varphi_t$ and the bentonite to clay volume ratio $R_b$ were varied. The contribution of this work is twofold: (i) to highlight the major role of $\varphi_t$ and $R_b$ independently on the rheology of binary-clay suspensions and (ii) to provide phenomenological models to quantify the dependency of the yield stress on both $\varphi_t$ and $R_b$ that would be particularly useful for industrial applications.

Published
2022

48. Comparison of the experimental response of two horizontal axis tidal turbines to wave and current from a frequency dependency point of view

Author

M.-A. Dufour, G. Pinon, B. Gaurier, G. Germain, J.-V. Facq, M. Togneri, F. Represas, E. Nicolas, J. Marcille, Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Laboratoire Comportement des Structures en Mer (LCSM), Recherches et Développements Technologiques (RDT), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), College of Engineering [Swansea], Swansea University, Magallanes Renovables [Redondela, Spain], Sabella, C. Guedes Soares (Ed.), and European Project: EAPA_333/2016,MONITOR

Subjects
[SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph]
Abstract

International audience; This paper studies wave influence on two horizontal axis tidal turbines developed by industrial partners: Sabella and Magallanes Renovables. The trials are performed in a wave and current flume tank where upstream flow conditions are monitored thanks to Laser Doppler Velocimetry. Wave amplitude and orbital amplitude are computed thanks to least mean square method. The turbulence is analysed through its intensity and a power spectral density point of view. A special attention is paid to turbine immersion depth. Global torque and thrust are analyzed in the frequency domain thanks to power spectral density and magnitude square coherence. Wave generates a strong torque and thrust fluctuation level of the same order as the mean effort level. Both torque and thrust respond to wave at wave and twice the wave frequency for all turbines whatever the immersion.

Published
2022

49. Collisional energy transfer in the CO-CO system

Author

Michał Żółtowski, Jérôme Loreau, François Lique, Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), European Research Council [811363], Institut Universitaire de France, Programme National 'Physique et Chimie du Milieu Interstellaire' (PCMI) of CNRS/INSU, CNES, CEA, CINES/GENCI [A0090411036], Wroclaw Centre for Networking and Supercomputing [218], KU Leuven [19-00313], and European Project: COLLEXISM

Subjects
ROTATIONAL-EXCITATION, [PHYS]Physics [physics], Science & Technology, DIMER, Chemistry, Physical, Physics, General Physics and Astronomy, Physics, Atomic, Molecular & Chemical, Chemistry, STATES, Physical Sciences, SCATTERING, Atomic and molecular collisions, Physical and Theoretical Chemistry, Quantum dynamics, Molecular physics
Abstract

An accurate determination of the physical conditions in astrophysical environments relies on the modeling of molecular spectra. In such environments, densities can be so low (n ≪ 1010 cm-3) that local thermodynamical equilibrium conditions cannot be maintained. Hence, radiative and collisional properties of molecules are needed to correctly model molecular spectra. For comets at large heliocentric distances, the production of carbon monoxide (CO) gas is found to be larger than the production of water, so that molecular excitation will be induced by collisions with CO molecules. This paper presents new scattering calculations for the collisional energy transfer in CO-CO collisions. Using the quantum coupled states approach, cross sections and rate coefficients are provided between the first 37 rotational states of the CO-CO system. Cross sections were calculated for energies up to 800 cm-1, and excitation rate coefficients were derived for temperatures up to 100 K. In comparison with data available in the literature, significant differences were found, especially for the dominant transitions. Due to the high cost of the calculations, we also investigated the possibility of using an alternative statistical approach to extend our calculations both in terms of rotational states and temperatures considered. The use of these new collisional data should help in accurately deriving the physical conditions in CO-dominated comets. ispartof: PHYSICAL CHEMISTRY CHEMICAL PHYSICS vol:24 issue:19 pages:11910-11918 ispartof: location:England status: published

Published
2022

50. Generalized homogenization model of piezoelectric materials for ultrasonic transducer applications

Author

Fidéle Léopold Hanse Wampo, Richard Ntenga, Joseph Yves Effa, Yuri Lapusta, Guy Edgar Ntamack, Pierre Maréchal, Groupe de Mécanique des Matériaux et l’Acoustique (GMMA), Université de Ngaoundéré/University of Ngaoundéré [Cameroun] (UN), Département de Physique [Univ Ngaoundéré] (UN-FS), Faculté de Sciences [Univ Ngaoundéré] (UN-FS), Université de Ngaoundéré/University of Ngaoundéré [Cameroun] (UN)-Université de Ngaoundéré/University of Ngaoundéré [Cameroun] (UN), Laboratoire d’Analyses Simulations et Essais (LASE), Institut Pascal (IP), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Institut national polytechnique Clermont Auvergne (INP Clermont Auvergne), Université Clermont Auvergne (UCA)-Université Clermont Auvergne (UCA), Laboratoire Ondes et Milieux Complexes (LOMC), Université Le Havre Normandie (ULH), and Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.MECA.MEMA]Physics [physics]/Mechanics [physics]/Mechanics of materials [physics.class-ph], Mechanics of Materials, Mechanical Engineering, Piezoelectric materials, Materials Chemistry, Ceramics and Composites, material connectivity, generalized homogenization models, ultrasonic transducers, [PHYS.MECA.ACOU]Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph]
Abstract

International audience; Although piezocomposite (PC) materials have increasingly attracted researchers, there is still a need to properly and easily derive their properties. We develop a generalized homogenization model (GHM) that accounts for Smith and Cha approaches to evaluate the equivalent characteristics of piezocomposites. This method could be applied to all connectivities patterns, but restricted herein to 2-2 and 1-3 piezocomposites for comparison with Smith (1-3) and Cha (2-2) analytical results. In the proposed GHM is a parameter θ, is changed for various connectivities. The 1-3 and 2-2 PZT-7A/Araldite D (PCs) data are used and equivalent characteristics of these Pcs are determined as function of volume fraction of PZT-7A piezoelectric. Results show that the electromechanical coefficients are well fitted by Voigt and Reuss models. Results obtained for some parameters show that the proposed GHM is consistent with the analytical existing models used for the 1-3 and 2-2 connectivities and is in line with measured values from Chan and Unsworth (1989). Based on the GHM 2-2 configuration results of piezocomposite materials, the electroacoustic responses of transducers having some of these properties are simulated using the KLM model. A performance trade-off was chosen, resulting in an improved thickness coupling coefficient and a lowered acoustical impedance, and a similar approach as that on a pure PZT-7A.

Published
2021

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