Laminar–turbulent transition experiment on the effect of surface imperfections on a natural laminar flow profile in compressible flow conditions Jeanne Methel, Fabien Méry, Olivier Vermeersch, Maxime Forte, Adrien Rouviere Experiments in Fluids, 2025 In the present study, the effect of various two-dimensional surface defects (forward-facing steps and ramps, backward-facing steps and ramps, gaps, and steps and gaps) on boundary layer transition was experimentally investigated in the compressible, subsonic regime. A laminar profile was specifically designed and manufactured by ONERA to allow for a maximum number of defects to be tested simultaneously, and to include resin pockets to accurately monitor laminar–turbulent transition using infrared thermography. Transition was also characterized using the $$\\Delta N$$ Δ N model based on linear stability calculations. Relatively good agreement with existing $$\\Delta N$$ Δ N models for forward-facing steps as well as gaps was found, indicating that these models, which were mostly developed for incompressible flows, can still be used as an initial estimate for compressible flows. One particular case of interest included a critical step and gap (for which transition occurred immediately downstream of the defect) where neither the gap nor the step component could be identified as mainly responsible for triggering transition. Steps and gaps should therefore be included whenever possible to the canonical shapes of defects investigated in transition experiments to further refine the different types of defect encountered in industrial application, and provide appropriate criteria for their allowable tolerances.
Development of Porous Ti64 by Partial Densification in Spark Plasma Sintering for Laminar Flow Control Baptiste Egreteau, Fabien Méry, Cécile Davoine, Olivier Vermeersch, Marc Thomas Advanced Engineering Materials, 2024 The purpose of this study is to develop a porous material in Ti64 by partial densification with spark plasma sintering to be used as a porous panel for laminar flow control by suction. An important characteristic of porous panels for this application is their permeability, which must be as high as possible. The permeability can be related to the material's porous network. This is why samples are made by varying their manufacturing parameters (temperature, pressure, powder particle size, and powder quantity). Then, their permeability is measured experimentally, and their porous network is described with the measurement of porosity, local diameter distribution, and tortuosity thanks to X‐ray tomography. The tortuosity measurements highlight the anisotropic effect of pressure on the porous network. The morphological parameters are used in a Kozeny–Carman model, which should predict porous materials’ permeability, and be confronted with the experimental measurements. Finally, this characterization process leads to the selection of the best manufacturing parameters for the application.
Aspect ratio-dependent etching in silicon using XeF2: experimental investigation and comparative analysis with dry etching methods Baptiste Baradel, Olivier Léon, Fabien Méry, Philippe Combette, Alain Giani Journal of Micromechanics and Microengineering, 2024 Silicon machining plays a crucial role in shaping three-dimensional structures for micro-electro-mechanical systems applications. This study investigates aspect ratio dependent etching (ARDE) across various silicon etching processes, with a particular focus on Xenon Difluoride etching, in comparison to reactive ion etching (RIE) and Deep RIE . By exploring different etching parameters, the study highlights the presence of ARDE in both plasma and non-plasma etching processes. Additionally, it is demonstrated that ARDE can be modeled by a saturating exponential function through experimental adjustment of parameters, enabling the estimation of etching profiles.
Systematic analysis of acoustic source localization maps for performance assessment Hélène PARISOT-DUPUIS, Jérémy JOMAIN, Bertrand MELLOT, Fabien MERY 53rd International Congress and Exposition on Noise Control Engineering Internoise 2024, 2024 Noise pollution is a raising problematic mainly associated to the development of industry, cities, and transportation. In that context, the characterization of noise sources is key point to help the understanding of noise generation mechanisms and to be able to develop effective noise reduction strategies. Microphones phased array measurements can be used as input to solve the inverse problem of source localization allowing to obtain source maps for each frequency of interest. Conventional beamforming (CBF) is the most famous source localization algorithm which uses the interpretation of the propagation delays measured between each array microphones. However, the analysis of output source maps can be made difficult by the low spatial resolution in the low-frequency range and the presence of side-lobes associated with microphones distribution that can lead to additional wrong sources. This paper presents a systematic analysis of source maps to identify potential noise sources by using different methods (local maxima, Metropolis-Hastings). The set of potential noise sources can then be compared to the set of real sources to assess the CBF performances. This methodology is successfully applied to measurements performed in anechoic room for various source configurations highlighting CBF limitations (spatial resolution, correlated sources, reflective environment).
ANALYSIS OF THE IMPACT OF FORCED PITCHING OSCILLATIONS IN TRANSONIC FLOW ON THE TRANSITION ONSET AND THE AEROELASTIC BEHAVIOUR OF AN AIRFOIL International Forum on Aeroelasticity and Structural Dynamics Ifasd 2024, 2024
Manufacturing Of a Porous Metallic Panel by Spark Plasma Sintering For Hybrid Laminar Flow Control Application World Pm 2022 Congress Proceedings, 2022
Assessment of In-Line particle image velocimetry for turbulence measurements in porous media AM d'Alexis, O Léon, D Donjat, R Roncen, F Mery The International Symposia on Applications of Laser and Imaging Techniques … , 2026 2026
Direct Time-Domain Eduction of Acoustic Liner Impedance in Turbulent Grazing Flows R Roncen, L Ambrosiani, A Paduano, F Avallone, F Méry, E Piot 2026
Metamaterials and fluid flows F Avallone, F Bosia, Y Chen, G Colombo, R Craster, JM De Ponti, ... Nature Communications , 2026 2026 Citations: 10
A Bayesian Approach for Rotating Source Localization Using Spherical Harmonic Decomposition B Etchebarne, B Sulis, H Parisot-Dupuis, F Mery 32nd AIAA/CEAS Aeroacoustics Conference (2026), 3473 , 2026 2026
Performance Study of Rotating Source Localization Algorithms Based on Analytical Models H Parisot-Dupuis, B Etchebarne, B Sulis, F Mery 32nd AIAA/CEAS Aeroacoustics Conference (2026), 3422 , 2026 2026
Time-Domain Evaluation of Acoustic Liner Impedance from LDV Measurements R Roncen, L Ambrosiani, E Piot, F Mery, F Avallone 32nd AIAA/CEAS Aeroacoustics Conference (2026), 3269 , 2026 2026
Friction Drag Measurements of Long Acoustic Liners in a Turbulent Channel Flow P Kraemer, F Mery, E Piot, O Léon 32nd AIAA/CEAS Aeroacoustics Conference (2026), 3202 , 2026 2026
Laser Doppler Velocimetry measurements of Acoustic–Turbulent Flow Interaction over a Liner L Ambrosiani, E Piot, F Mery, F Avallone 32nd AIAA/CEAS Aeroacoustics Conference (2026), 3201 , 2026 2026
Fabrication and characterization of a streamlined micro hot wire probe to reduce aerodynamic disturbances B Baradel, O Léon, L Chamard, P Combette, F Méry, A Giani Micro and Nano Engineering 29, 100326 , 2025 2025
Laminar–turbulent transition experiment on the effect of surface imperfections on a natural laminar flow profile in compressible flow conditions J Methel, F Méry, O Vermeersch, M Forte, A Rouviere Experiments in Fluids 66 (9), 175 , 2025 2025 Citations: 2
Mesure de la traînée de frottement de liners acoustiques P Kraemer, F Méry, E Piot, O Léon 17e Congrès Français d'Acoustique , 2025 2025
Construction d'une Base de Données Expérimentale par Mesure Optique pour l'Etude des Interactions Aéroacoustiques en Présence de Liners L Ambrosiani, F Méry, E Piot, F Avallone 17e Congrès Français d'Acoustique , 2025 2025
Liners acoustiques dans un conduit avec écoulement: récentes avancées à l'ONERA sur leur modélisation et leur caractérisation expérimentale E Piot, R Roncen, F Méry, V Lafont CFA 2025-Congres Francais d'Acoustique , 2025 2025
Travaux expérimentaux sur la caractérisation multiphysique de liners acoustiques et de la transition laminaire-turbulent F Méry Université toulouse 3 Paul Sabatier , 2025 2025
HOVERING SMALL-SCALE LOW REYNOLDS NUMBER ROTOR-BEAM SOURCE LOCALIZATION USING BOTH NEARFIELD AND FARFIELD MEASUREMENTS H Parisot-Dupuis, B Mellot, N Gariglio, F Méry 2025
Experimental investigation of porous media turbulence AM d’Alexis, L Ambrosiani, O Leon, F Mery, D Donjat, R Roncen ICHMT DIGITAL LIBRARY ONLINE , 2025 2025
Hybrid Laminar Flow Control investigation of microperforated skin with variable porosity suction device F Mery, E Piot, M Forte, B Aguilar, JL Godard, P Bardoux AIAA SciTech 2025 Forum, 1646 , 2025 2025 Citations: 4
Aspect ratio-dependent etching in silicon using XeF 2 : experimental investigation and comparative analysis with dry etching methods B Baradel, O Léon, F Méry, P Combette, A Giani Journal of Micromechanics and Microengineering 34 (12), 125002 , 2024 2024 Citations: 3
Development of Porous Ti64 by Partial Densification in Spark Plasma Sintering for Laminar Flow Control B Egreteau, F Méry, C Davoine, O Vermeersch, M Thomas Advanced Engineering Materials 26 (23), 2401096 , 2024 2024
Systematic analysis of acoustic source localization maps for performance assessment H Parisot-Dupuis, J Jomain, B Mellot, F Méry INTER-NOISE and NOISE-CON Congress and Conference Proceedings 270 (2), 9675-9686 , 2024 2024
MOST CITED SCHOLAR PUBLICATIONS
Near-wall aerodynamic response of an acoustic liner to harmonic excitation with grazing flow O Léon, F Méry, E Piot, C Conte Experiments in fluids 60 (9), 144 , 2019 2019 Citations: 50
Liner impedance eduction under shear grazing flow at a high sound pressure level V Lafont, F Méry, R Roncen, F Simon, E Piot AIAA Journal 58 (3), 1107-1117 , 2020 2020 Citations: 42
Wavenumber-based impedance eduction with a shear grazing flow R Roncen, E Piot, F Méry, F Simon, MG Jones, DM Nark AIAA Journal 58 (7), 3040-3050 , 2020 2020 Citations: 34
Statistical inference method for liner impedance eduction with a shear grazing flow R Roncen, F Mery, E Piot, F Simon AIAA Journal 57 (3), 1055-1065 , 2019 2019 Citations: 34
Spatially-varying impedance model for locally reacting acoustic liners at a high sound intensity R Roncen, F Méry, E Piot, P Klotz Journal of Sound and Vibration 524, 116741 , 2022 2022 Citations: 30
Bayesian inference for modal identification in ducts with a shear flow R Roncen, F Méry, E Piot The Journal of the Acoustical Society of America 146 (4), 2645-2654 , 2019 2019 Citations: 21
Experimental assessment of the effect of temperature gradient across an aeroacoustic liner F Mery, E Piot, D Sebbane, P Reulet, F Simon, A Carazo Méndez Journal of Aircraft 56 (5), 1809-1821 , 2019 2019 Citations: 15
Experimental and numerical study on wall impedance effects on Tollmien–Schlichting Waves A Rouviere, F Méry, J Methel, O Vermeersch, M Forte AIAA Journal 60 (1), 508-519 , 2022 2022 Citations: 13
Influence of source propagation direction and shear flow profile in impedance eduction of acoustic liners R Roncen, E Piot, F Mery, F Simon, MG Jones, DM Nark 25th AIAA/CEAS Aeroacoustics Conference, 2469 , 2019 2019 Citations: 13
Surface temperature measurement of acoustic liners in the presence of grazing flow and thermal gradient V Lafont, F Méry, P Reulet, F Simon Experiments in Fluids 62 (4), 82 , 2021 2021 Citations: 12
Metamaterials and fluid flows F Avallone, F Bosia, Y Chen, G Colombo, R Craster, JM De Ponti, ... Nature Communications , 2026 2026 Citations: 10
Aerodynamic characterisation of porous fairings: Pressure drop and laser Doppler velocimetry measurements F Méry, D Sebbane Scientific Data 10 (1), 39 , 2023 2023 Citations: 10
A micro-hot-wire anemometry probe with elongated stubs for turbulent boundary layer measurements B Baradel, A Giani, F Méry, P Combette, O Léon Experiments in Fluids 65 (9), 133 , 2024 2024 Citations: 9
Far field wall-mounted microphone device for the S1MA anechoic closed-section wind tunnel applied to Open Rotor F Mery, M Rey, R Davy, R Fernando 18th AIAA/CEAS Aeroacoustics Conference (33rd AIAA Aeroacoustics Conference … , 2012 2012 Citations: 9
Neural prediction model for transition onset of a boundary-layer in presence of 2D surface defects A Rouviere, L Pascal, F Méry, E Simon, S Gratton AIAA SCITECH 2022 Forum, 1073 , 2022 2022 Citations: 8
Design and optimization of acoustic liners with a shear grazing flow: OPAL software platform applications R Roncen, P Vuillemin, P Klotz, F Simon, F Méry, D Sebbane, E Piot INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263 (6), 152-163 , 2021 2021 Citations: 8
Acoustic liner demonstrator for a turning vane of S1MA wind tunnel F Méry, R Roncen, F Simon, M Botte, L Ostorero Journal of Aircraft 60 (4), 1314-1322 , 2023 2023 Citations: 7
Liner multiphysics coupling between grazing flow, thermal gradients, and sound pressure levels V Lafont, F Méry, F Simon AIAA Journal 60 (8), 4754-4763 , 2022 2022 Citations: 6
Design and optimization of acoustic liners with a shear grazing flow: OPAL software platform description F Simon, R Roncen, P Vuillemin, P Klotz, F Méry, E Piot INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263 (6), 508-518 , 2021 2021 Citations: 6
Low speed anechoic closed test section at ONERA S1MA Wind tunnel F Mery 22nd AIAA/CEAS Aeroacoustics Conference, 2895 , 2016 2016 Citations: 6
