Metamaterials and Fluid Flows Francesco Avallone, Federico Bosia, Yi Chen, Giada Colombo, Richard Craster, Jacopo Maria De Ponti, Nicolò Fabbiane, Michael R. Haberman, Mahmoud I. Hussein, Wontae Hwang, Umberto Iemma, Abigail Juhl, Muamer Kadic, Marios Kotsonis, Vincent Laude, Olivier Marquet, Fabien Mery, Theodoros Michelis, Mostafa Nouh, Daniele Ragni, Marie Touboul, Martin Wegener, Anastasiia O. Krushynska Nature Communications, 2026 Understanding and controlling the dynamic interactions between fluid flows and solid materials and structures-a field known as fluid-structure interaction-is central not only to established disciplines such as aerospace and naval engineering, but also to emerging technologies such as energy harvesting, soft robotics, and biomedical devices. In recent years, the advent of metamaterials has provided exciting opportunities to rethink and redesign fluid-structure interactions. The idea of engineering the internal structure of materials that interface with fluid flows opens a new horizon for the precise and effective manipulation and control of coupled fluidic, acoustic, and elastodynamic responses. This review focuses on this relatively unexplored interdisciplinary theme with broad technological significance. Salient potential applications, such as reduction of fuel consumption in transport systems, efficiency of renewable energy extraction, noise mitigation, and resilience against structural fatigue, depend on controlling interactions among flow, acoustic, and vibration mechanisms. Flow control, for example, which spans a wealth of regimes such as laminar, transitional, turbulent, and unsteady separated flows, is strongly influenced by fluid-structure interaction. This review surveys and discusses conceptual frameworks that describe the interplay between fluids and elastic solids, with a focus on contemporary and emerging concepts. The paper is organised into three main sections: fluid-structure and flow-phonon interactions, flow-induced acoustic interactions with metamaterials, and exotic metamaterial concepts with potential impact on fluid-structure interaction. It concludes with perspectives on current challenges and future directions in this rapidly expanding area of research.
Fabrication and characterization of a streamlined micro hot wire probe to reduce aerodynamic disturbances Baptiste Baradel, Olivier Léon, Léo Chamard, Philippe Combette, Fabien Méry, Alain Giani Micro and Nano Engineering, 2025 The miniaturization of sensing elements in hot-wire anemometry through micro-fabrication techniques enables high temporal and spatial resolution, essential for investigating complex and high-speed flows. However, hot-wire probes remain inherently intrusive, and minimizing disturbances caused by the probe is critical for accurate measurements at small scales. This study focuses on the development of a micro hot-wire ( x μ HW) sensor with reduced disturbances through the implementation of a streamlined geometry. By developing a micro-fabrication process, based among others on silicon’s aspect ratio-dependent etching properties, a new sensor prototype was produced. Experimental characterization in a wall-bounded flow highlights the potential and limitations of this streamlined design for aerodynamic applications. • Developed a streamlined micro-sensor to reduce flow disturbance during measurement. • Demonstrated benefits of micro-sensor shaping in free-stream turbulence conditions. • Used silicon etching techniques to create a 3D aerodynamic micro-probe geometry.
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.
Experimental investigation of porous media turbulence A. Mure d’Alexis, L. Ambrosiani, O. Leon, F. Mery, D. Donjat, R. Roncen Proceedings of the International Symposium on Turbulence Heat and Mass Transfer, 2025 International audience
Hybrid Laminar Flow Control investigation of microperforated skin with variable porosity suction device Fabien Mery, Estelle Piot, Maxime Forte, Boris Aguilar, Jean-Luc Godard, Philippe Bardoux AIAA Science and Technology Forum and Exposition AIAA Scitech Forum 2025, 2025 Reduction of the specific consumption of aircraft would lead to substantial economic and environmental benefits. A promising technique consists in reducing skin friction drag by delaying the laminar-turbulent transition point as far aft as possible, particularly on the wings, in order to obtain lower friction coefficient in the presence of laminar flow. This can be achieved by Hybrid Laminar Flow Control (HLFC) technology. This paper presents the windtunnel tests of a large-scale HLFC wing model conducted in ONERA’s S1MA wind-tunnel. The wing model is designed to investigate the efficiency of a variable porosity microperforated titanium suction cartridge and to assess the attachement line contamination phenomena.
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.
A micro-hot-wire anemometry probe with elongated stubs for turbulent boundary layer measurements Baptiste Baradel, Alain Giani, Fabien Méry, Philippe Combette, Olivier Léon Experiments in Fluids, 2024 The development of micro-hot-wire anemometry probes for turbulence studies requires mitigating spatial filtering, end-conduction effects and probe intrusivity. Keeping these factors in mind, this work analytically and experimentally investigates the relevance of a micro-hot-wire probe design featuring elongated stubs, inspired by Wollaston-wire probes but fabricated using modern micro-fabrication techniques. The resulting probes are shown to be relatively easy to manufacture and capable of providing satisfactory velocity measurements in a zero-pressure-gradient turbulent boundary layer at $$\text {Re}_{\tau }\approx 1150$$ with $$\delta ={18}{\hbox {mm}}$$ . Different probes were tested, all featuring a micro-wire length sufficiently small to alleviate spatial filtering of near-wall small-scale turbulent structures. The investigation focuses on assessing end-conduction effects and probe intrusivity, with the latter still observable close to the wall for such micro-probes.
Influence of innovative porous panels for laminar flow control by suction Baptiste Egreteau, Arnaud Mure d'Alexis, Fabien Mery, Cécile Davoine AIAA Aviation Forum and Ascend 2024, 2024 This paper presents the development process of a new porous titanium panel made by Spark Plasma Sintering (SPS) for laminar flow control by suction. First, the development process of the porous panel is detailed. Small samples are produced by partial sintering in SPS. Then, they are characterised in permeability and surface roughness. Based on these data, the sample with the most interesting characteristics is chosen to be upscaled and make a full suction panel of 300 × 275mm. Afterwards, this new SPS panel is mounted on an academic flat plate model equipped with suction chambers to delay the boundary layer transition by applying wall suction. It is ensured there is a bidimensional with zero pressure gradient grazing flow in a low disturbance wind tunnel, leading to a modal boundary-layer transition scenario. Then, the transition position is determined using hot-wire anemometry for three configurations: a smooth reference case, a case with the SPS panel without suction and a case with the SPS panel and wall suction. These results are then compared with a previous study led in the same flow conditions with microperforated titanium sheets as porous panel.
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
Inlet liner design for aircraft air conditioning system Inter Noise 2019 Madrid 48th International Congress and Exhibition on Noise Control Engineering, 2019
Non-intrusive measurements of velocity fields over a lined wall in a turbulent duct flow for drag assessment 23rd AIAA Ceas Aeroacoustics Conference 2017, 2017
S1MA high speed acoustic measurement devices for open rotor mock up 19th AIAA Ceas Aeroacoustics Conference, 2013
Far field wall-mounted microphone device for the S1MA anechoic closed-section wind tunnel applied to Open Rotor 18th AIAA Ceas Aeroacoustics Conference 33rd AIAA Aeroacoustics Conference, 2012
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
