https://sam.ensam.eu:443 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Wed, 15 Apr 2026 22:52:10 GMT 2026-04-15T22:52:10Z http://hdl.handle.net/10985/10253 On the multi‑scale description of electrical conducting suspensions involving perfectly dispersed rods PEREZ, Marta; ABISSET-CHAVANNE, Emmanuelle; BARASINSKI, Anais; CHINESTA SORIA, Francisco; AMMAR, Amine; KEUNINGS, Roland Nanocomposites allow for a significant enhancement of functional properties, in particular electrical conduction. In order to optimize materials and parts, predictive models are required to evaluate particle distribution and orientation. Both are key parameters in order to evaluate percolation and the resulting electrical networks. Many forming processes involve flowing suspensions for which the final particle orientation could be controlled by means of the flow and the electric field. In view of the multiscale character of the problem, detailed descriptions are defined at the microscopic scale and then coarsened to be applied efficiently in process simulation at the macroscopic scale. The first part of this work revisits the different modeling approaches throughout the different description scales. Then, modeling of particle contacts is addressed as they determine the final functional properties, in particular electrical conduction. Different descriptors of rod contacts are proposed and analyzed. Numerical results are discussed, in particular to evaluate the impact of closure approximations needed to derive a macroscopic description. Thu, 01 Jan 2015 00:00:00 GMT http://hdl.handle.net/10985/10253 2015-01-01T00:00:00Z PEREZ, Marta ABISSET-CHAVANNE, Emmanuelle BARASINSKI, Anais CHINESTA SORIA, Francisco AMMAR, Amine KEUNINGS, Roland Nanocomposites allow for a significant enhancement of functional properties, in particular electrical conduction. In order to optimize materials and parts, predictive models are required to evaluate particle distribution and orientation. Both are key parameters in order to evaluate percolation and the resulting electrical networks. Many forming processes involve flowing suspensions for which the final particle orientation could be controlled by means of the flow and the electric field. In view of the multiscale character of the problem, detailed descriptions are defined at the microscopic scale and then coarsened to be applied efficiently in process simulation at the macroscopic scale. The first part of this work revisits the different modeling approaches throughout the different description scales. Then, modeling of particle contacts is addressed as they determine the final functional properties, in particular electrical conduction. Different descriptors of rod contacts are proposed and analyzed. Numerical results are discussed, in particular to evaluate the impact of closure approximations needed to derive a macroscopic description. http://hdl.handle.net/10985/14642 On the Proper Generalized Decomposition applied to microwave processes involving multilayered components TERTRAIS, Hermine; IBANEZ PINILLO, Ruben; BARASINSKI, Anais; GHNATIOS, Chady; CHINESTA SORIA, Francisco Many electrical and structural components are constituted of a stacking of multiple thin layers with different electromagnetic, mechanical and thermal properties. When 3D descriptions become compulsory the approximation of the fields along the thickness direction could involve thousands of nodes. To circumvent the numerical difficulties that such a rich description imply, we recently propose an in-plane–out-of-plane separated representation with the aim of computing fully 3D solutions as a sequence of 2D problems defined in the plane and others (1D) in the thickness. The main contribution of the present work is the proposal of an efficient in-plane–out-of-plane separated representation of the double-curl formulation of Maxwell equations able to address thin-layer laminates while ensuring the continuity and discontinuity of the tangential and normal electric field components respectively at the plies interface Tue, 01 Jan 2019 00:00:00 GMT http://hdl.handle.net/10985/14642 2019-01-01T00:00:00Z TERTRAIS, Hermine IBANEZ PINILLO, Ruben BARASINSKI, Anais GHNATIOS, Chady CHINESTA SORIA, Francisco Many electrical and structural components are constituted of a stacking of multiple thin layers with different electromagnetic, mechanical and thermal properties. When 3D descriptions become compulsory the approximation of the fields along the thickness direction could involve thousands of nodes. To circumvent the numerical difficulties that such a rich description imply, we recently propose an in-plane–out-of-plane separated representation with the aim of computing fully 3D solutions as a sequence of 2D problems defined in the plane and others (1D) in the thickness. The main contribution of the present work is the proposal of an efficient in-plane–out-of-plane separated representation of the double-curl formulation of Maxwell equations able to address thin-layer laminates while ensuring the continuity and discontinuity of the tangential and normal electric field components respectively at the plies interface http://hdl.handle.net/10985/13282 Wavelet-based multiscale proper generalized decomposition ANGEL, Leon; BARASINSKI, Anais; CUETO, Elias; ABISSET-CHAVANNE, Emmanuelle; CHINESTA SORIA, Francisco Separated representations at the heart of Proper Generalized Decomposition are constructed incrementally by minimizing the problem residual. However, the modes involved in the resulting decomposition do not exhibit a clear multi-scale character. In order to recover a multi-scale description of the solution within a separated representation framework, we study the use of wavelets for approximating the functions involved in the separated representation of the solution. We will prove that such an approach allows separating the different scales as well as taking profit from its multi-resolution behavior for defining adaptive strategies. Mon, 01 Jan 2018 00:00:00 GMT http://hdl.handle.net/10985/13282 2018-01-01T00:00:00Z ANGEL, Leon BARASINSKI, Anais CUETO, Elias ABISSET-CHAVANNE, Emmanuelle CHINESTA SORIA, Francisco Separated representations at the heart of Proper Generalized Decomposition are constructed incrementally by minimizing the problem residual. However, the modes involved in the resulting decomposition do not exhibit a clear multi-scale character. In order to recover a multi-scale description of the solution within a separated representation framework, we study the use of wavelets for approximating the functions involved in the separated representation of the solution. We will prove that such an approach allows separating the different scales as well as taking profit from its multi-resolution behavior for defining adaptive strategies. http://hdl.handle.net/10985/19483 Empowering Design Based on Hybrid TwinTM: Application to Acoustic Resonators MARTÍN, Clara Argerich; MÉNDEZ, Arnulfo Carazo; SAINGES, Olivier; PETIOT, Emilie; BARASINSKI, Anais; PIANA, Mathieu; RATIER, Louis; CHINESTA SORIA, Francisco In the framework of civil aviation noise levels are becoming restricted every year, on one hand to provide comfort to the passengers and on the other hand to be compliant with regulations protecting airports surroundings. New technologies are required to reduce noise to cope with this restrictions as well as to guarantee a comfortable flight for passengers. For technological industries it is compulsory to stay competitive and keep improving the technology related to air intake acoustic liners. With an unceasingly growing market, for industries it is key to stay in the vanguard of air inlet technologies, ensuring innovation and establishing a proactive environment for future product generations. One of the main objectives in this framework is the reduction of the development time of these new technologies in all the stages of the process. In this work we focus on the design stage of a new prototype and we propose a hybrid technique enabling faster design and the reduction of development time. When designing new technologies or prototypes there are usually two constraints. On one hand, more innovative prototypes may present unconventional shapes are not accurately represented by conventional physical models. On the other hand, the available data is scarce, thus limiting the use of most innovative techniques based on the state-of-art of Artificial Intelligence. In this paper we propose a solution laying in the hybrid twin paradigm, combining both, data in the low limit and physics to provide a hybrid model able to represent unconventional and innovative acoustic solutions. Wed, 01 Jan 2020 00:00:00 GMT http://hdl.handle.net/10985/19483 2020-01-01T00:00:00Z MARTÍN, Clara Argerich MÉNDEZ, Arnulfo Carazo SAINGES, Olivier PETIOT, Emilie BARASINSKI, Anais PIANA, Mathieu RATIER, Louis CHINESTA SORIA, Francisco In the framework of civil aviation noise levels are becoming restricted every year, on one hand to provide comfort to the passengers and on the other hand to be compliant with regulations protecting airports surroundings. New technologies are required to reduce noise to cope with this restrictions as well as to guarantee a comfortable flight for passengers. For technological industries it is compulsory to stay competitive and keep improving the technology related to air intake acoustic liners. With an unceasingly growing market, for industries it is key to stay in the vanguard of air inlet technologies, ensuring innovation and establishing a proactive environment for future product generations. One of the main objectives in this framework is the reduction of the development time of these new technologies in all the stages of the process. In this work we focus on the design stage of a new prototype and we propose a hybrid technique enabling faster design and the reduction of development time. When designing new technologies or prototypes there are usually two constraints. On one hand, more innovative prototypes may present unconventional shapes are not accurately represented by conventional physical models. On the other hand, the available data is scarce, thus limiting the use of most innovative techniques based on the state-of-art of Artificial Intelligence. In this paper we propose a solution laying in the hybrid twin paradigm, combining both, data in the low limit and physics to provide a hybrid model able to represent unconventional and innovative acoustic solutions. http://hdl.handle.net/10985/19936 Electromagnetic field propagation in a composite laminate and induced thermal field BARASINSKI, Anais; GHNATIOS, Chady; ABENIUS, Erik; BECHTEL, Stephane; CHINESTA SORIA, Francisco Microwave (MW) technology relies on volumetric heating, where thermal energy is induced from an electromagnetic field. Nowadays, the main drawback of this technology is that the complex physics involved in the conversion of electromagnetic energy into thermal energy is not entirely understood and controlled. The main objective of this work is to model, simulate and validate the interactions of microwaves with a composite laminate consisting of a stack of unidirectional layers composed of a resin matrix and carbon fibers, to predict its heating. Once validated, this simulation tool will serve to predict, control and optimize composites forming processes. Fri, 01 Jan 2021 00:00:00 GMT http://hdl.handle.net/10985/19936 2021-01-01T00:00:00Z BARASINSKI, Anais GHNATIOS, Chady ABENIUS, Erik BECHTEL, Stephane CHINESTA SORIA, Francisco Microwave (MW) technology relies on volumetric heating, where thermal energy is induced from an electromagnetic field. Nowadays, the main drawback of this technology is that the complex physics involved in the conversion of electromagnetic energy into thermal energy is not entirely understood and controlled. The main objective of this work is to model, simulate and validate the interactions of microwaves with a composite laminate consisting of a stack of unidirectional layers composed of a resin matrix and carbon fibers, to predict its heating. Once validated, this simulation tool will serve to predict, control and optimize composites forming processes. http://hdl.handle.net/10985/19161 Tape surfaces characterization with persistence images FRAHI, Tarek; ARGERICH, Clara; YUN, Minyoung; FALCO, Antonio; BARASINSKI, Anais; CHINESTA SORIA, Francisco The aim of this paper is to leverage the main surface topological descriptors to classify tape surface profiles, through the modelling of the evolution of the degree of intimate contact along the consolidation of pre-impregnated preforms associated to a composite forming process. It is well-known at an experimental level that the consolidation degree strongly depends on the surface characteristics (roughness). In particular, same process parameters applied to di erent surfaces produce very di erent degrees of intimate contact. It allows us to think that the surface topology plays an important role along this process. However, solving the physics-based models for simulating the roughness squeezing occurring at the tapes interface represents a computational e ort incompatible with online process control purposes. An alternative approach consists of taking a population of di erent tapes, with di erent surfaces, and simulating the consolidation for evaluating for each one the progression of the degree of intimate contact –DIC– while compressing the heated tapes, until reaching its final value at the end of the compression. The final goal is creating a regression able to assign a final value of the DIC to any surface, enabling online process control. The main issue of such an approach is the rough surface description, that is, the most precise and compact way of describing it from some appropriate parameters easy to extract experimentally, to be included in the just referred regression. In the present paper we consider a novel, powerful and very promising technique based on the topological data analysis –TDA– that considers an adequate metrics to describe, compare and classify rough surfaces. Wed, 01 Jan 2020 00:00:00 GMT http://hdl.handle.net/10985/19161 2020-01-01T00:00:00Z FRAHI, Tarek ARGERICH, Clara YUN, Minyoung FALCO, Antonio BARASINSKI, Anais CHINESTA SORIA, Francisco The aim of this paper is to leverage the main surface topological descriptors to classify tape surface profiles, through the modelling of the evolution of the degree of intimate contact along the consolidation of pre-impregnated preforms associated to a composite forming process. It is well-known at an experimental level that the consolidation degree strongly depends on the surface characteristics (roughness). In particular, same process parameters applied to di erent surfaces produce very di erent degrees of intimate contact. It allows us to think that the surface topology plays an important role along this process. However, solving the physics-based models for simulating the roughness squeezing occurring at the tapes interface represents a computational e ort incompatible with online process control purposes. An alternative approach consists of taking a population of di erent tapes, with di erent surfaces, and simulating the consolidation for evaluating for each one the progression of the degree of intimate contact –DIC– while compressing the heated tapes, until reaching its final value at the end of the compression. The final goal is creating a regression able to assign a final value of the DIC to any surface, enabling online process control. The main issue of such an approach is the rough surface description, that is, the most precise and compact way of describing it from some appropriate parameters easy to extract experimentally, to be included in the just referred regression. In the present paper we consider a novel, powerful and very promising technique based on the topological data analysis –TDA– that considers an adequate metrics to describe, compare and classify rough surfaces. http://hdl.handle.net/10985/19486 On the effective conductivity and the apparent viscosity of a thin rough polymer interface using PGD‐based separated representations GHNATIOS, Chady; DELPLACE, Frank; BARASINSKI, Anais; DUVAL, Jean-Louis; CUETO, Elias; AMMAR, Amine; CHINESTA SORIA, Francisco Composite manufacturing processes usually proceed from preimpregnated preforms that are consolidated by simultaneously applying heat and pressure, so as to ensure a perfect contact compulsory for making molecular diffusion possible. However, in practice, the contact is rarely perfect. This results in a rough interface where air could remain entrapped, thus affecting the effective thermal conductivity. Moreover, the interfacial melted polymer is squeezed flowing in the rough gap created by the fibers located on the prepreg surfaces. Because of the typical dimensions of a composite prepreg, with thickness orders of magnitude smaller than its other in-plane dimensions, and its surface roughness having a characteristic size orders of magnitude smaller than the prepreg thickness, high-fidelity numerical simulations for elucidating the impact of surface and interface roughness remain today, despite the impressive advances in computational availabilities, unattainable. This work aims at elucidating roughness impact on heat conduction and the effective viscosity of the interfacial polymer squeeze flow by using an advanced numerical strategy able to reach resolutions never attained until now, a sort of numerical microscope able to attain the scale of the smallest geometrical detail. Wed, 01 Jan 2020 00:00:00 GMT http://hdl.handle.net/10985/19486 2020-01-01T00:00:00Z GHNATIOS, Chady DELPLACE, Frank BARASINSKI, Anais DUVAL, Jean-Louis CUETO, Elias AMMAR, Amine CHINESTA SORIA, Francisco Composite manufacturing processes usually proceed from preimpregnated preforms that are consolidated by simultaneously applying heat and pressure, so as to ensure a perfect contact compulsory for making molecular diffusion possible. However, in practice, the contact is rarely perfect. This results in a rough interface where air could remain entrapped, thus affecting the effective thermal conductivity. Moreover, the interfacial melted polymer is squeezed flowing in the rough gap created by the fibers located on the prepreg surfaces. Because of the typical dimensions of a composite prepreg, with thickness orders of magnitude smaller than its other in-plane dimensions, and its surface roughness having a characteristic size orders of magnitude smaller than the prepreg thickness, high-fidelity numerical simulations for elucidating the impact of surface and interface roughness remain today, despite the impressive advances in computational availabilities, unattainable. This work aims at elucidating roughness impact on heat conduction and the effective viscosity of the interfacial polymer squeeze flow by using an advanced numerical strategy able to reach resolutions never attained until now, a sort of numerical microscope able to attain the scale of the smallest geometrical detail. http://hdl.handle.net/10985/22298 On the High-Resolution Discretization of the Maxwell Equations in a Composite Tape and the Heating Effects Induced by the Dielectric Losses GHNATIOS, Chady; BARASINSKI, Anais; CHINESTA SORIA, Francisco Electromagnetic field propagation inside composite materials represents a challenge where fiber-scale simulation remains intractable using classical simulation methods. The present work proposes an original 3D simulation with a mesh resolution fine enough to resolve the fiber scale, thanks to the use of Proper Generalized Decomposition (PGD)-based space decomposition, which avoids the necessity of considering homogenized properties and considers the richest description of the involved physics from the solution of the Maxwell equations. This high-resolution simulation enables comparing the electromagnetic field propagation in a composite part, depending on the considered frequency and the fiber’s/wave polarization’s relative orientation. The electromagnetic fields are then post-processed to identify the heat generation terms and- the resulting induced thermal field. The results prove the ability of the PGD-based discretization to attain extremely high levels of resolution, the equivalent of 1010 finite-element degrees of freedom. The obtained results show an enhanced wave penetration when the electric field polarization coincides with the fiber orientation. On the contrary, when the electric field is polarized along the normal to the fiber orientation, both the penetration and the associated heating reduce significantly, compromising the use of homogenized models, rendering them unable to reproduce the observed behaviors. Sat, 01 Jan 2022 00:00:00 GMT http://hdl.handle.net/10985/22298 2022-01-01T00:00:00Z GHNATIOS, Chady BARASINSKI, Anais CHINESTA SORIA, Francisco Electromagnetic field propagation inside composite materials represents a challenge where fiber-scale simulation remains intractable using classical simulation methods. The present work proposes an original 3D simulation with a mesh resolution fine enough to resolve the fiber scale, thanks to the use of Proper Generalized Decomposition (PGD)-based space decomposition, which avoids the necessity of considering homogenized properties and considers the richest description of the involved physics from the solution of the Maxwell equations. This high-resolution simulation enables comparing the electromagnetic field propagation in a composite part, depending on the considered frequency and the fiber’s/wave polarization’s relative orientation. The electromagnetic fields are then post-processed to identify the heat generation terms and- the resulting induced thermal field. The results prove the ability of the PGD-based discretization to attain extremely high levels of resolution, the equivalent of 1010 finite-element degrees of freedom. The obtained results show an enhanced wave penetration when the electric field polarization coincides with the fiber orientation. On the contrary, when the electric field is polarized along the normal to the fiber orientation, both the penetration and the associated heating reduce significantly, compromising the use of homogenized models, rendering them unable to reproduce the observed behaviors.