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Cressin, Maxime. "Contribution au développement d'un modèle thermomécanique de mise en forme du verre par le procédé soufflé-soufflé incluant les effets radiatifs". Electronic Thesis or Diss., Valenciennes, Université Polytechnique Hauts-de-France, 2023. http://www.theses.fr/2023UPHF0023.
Pełny tekst źródłaThis thesis deals with the numerical modeling of glass forming by the blow and blow process, allowing the glass forming of glass in two blowing steps. The bibliographic study has shown that in order to efficiently simulate this process, it is necessary to take two important parameters into account: the thermal radiation of the glass and the thermal exchange between the glass and the tools. This thermal exchange is represented by the experimentally identified heat transfer coefficient hc. A 1D numerical thermal model taking the radiative effects into account has been developed to simulate the contact between a metal punch and a glass cylinder. This model was coupled with an inverse identification methodology to determine hc from experimental data. The influence of the glass temperature, of the thermocouple position and of the radiation on the identification of hc has been studied. The originality of this work concerns the inclusion of radiation in the identification of hc as well as the use of the Back Ray Tracing (BRT) method to solve the radiative transfer equation (RTE) in 2D axisymmetric. The code is coupled with the Abaqus/Standard software to take the radiation of the glass into account in the simulation of the forming process. Finally, a thermomechanical finite element model has been implemented in Abaqus/Standard in order to simulate the 2D axisymmetric blow and blow process of a standard glass bottle. A discussion is made on the contribution of the experimentally identified heat transfer coefficient and the radiation model on the formability of the bottle
Saumabere, Denis. "Modélisation numérique magnéto-thermique avec prise en compte du transfert radiatif dans les procédés d'élaboration des verres par induction en creuset froid". Grenoble INPG, 1994. http://www.theses.fr/1994INPG0151.
Pełny tekst źródłaThe cold crucible induction process applied to glasses presents incomparable advantages related to the absence of contact between the molten glass, highly reactive material, and the crucible wall. The development of such methods is complex and delicate. Numerical modeling is a tool for analysis and extrapolation. Analysis of physical phenomena existing in the studied method shows a wide variation in physical properties of the glass depending on both temperature and composition, a strong interaction between the electromagnetic and thermal phenomena and the occurrence of a heat source further in the case of semi-transparent glasses due to radiative transfer. The thesis presents, after a bibliographic study on different methods to model the radiative transfer, a model of this phenomenon by a discrete method of based on finite elements. The coupling of electromagnetic and thermal phenomena taking into account radiative transfer is made. The strong interdependence of these three phenomena is modeled. In addition to each of the modeled phenomena the most appropriate numerical method is chosen. A validation of the model with thermal radiative transfer is done by comparison with examples found in the literature. A campaign on industrial prototype is carried out for a first validation of the model with thermo-magnetic radiation transfer
Béraud, Nicolas. "Fabrication assistée par ordinateur pour le procédé EBM". Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI052/document.
Pełny tekst źródłaThe Electron Beam Melting (EBM) process allows to build metallic parts from powder. Thanks to the geometric and mechanical quality of the parts produced, the EBM process can be used to manufacture functional parts and not only prototypes. This process, with other additive metallic processes, make it possible to consider a transition from 3D printing to metallic additive manufacturing.The use of additive manufacturing in an industrial environment requires compliance with quality, cost and time criteria for the parts produced. The production of manufactured parts involves a series of numerical stages which is called the numerical chain. The numerical chain has a significant impact on the three criteria mentioned above. Thus, this thesis provides an answer to the following question:How Computer Aided Manufacturing can improve the quality, cost and time of the EBM manufacturing process?This problem is addressed through the following underlying question:What are the required characteristics for a Computer Aided Manufacturing system adapted to the EBM process?In order to answer this question, the current numerical chain is analyzed. Three main limitations are found:- the use of STL files format- the process cannot be optimized at different scales- the process cannot be simulatedTo solve these issues, a CAM environment is proposed. It allows the centralization of all numerical operations in a single environment. All supported formats can be used within this environment, such as native CAD file formats or STEP format. Software developments are done to prove the feasibility of such an environment.The CAM environment implementation reveals the crucial role of simulation in this system. It is therefore necessary to answer this second question:How to obtain an EBM process simulation allowing the development of parameters, virtually?Although EBM simulation is a recurrent subject in scientific literature, existing studies are based on the finite elements method but the calculation time needed is too important to be used in an CAM environment. Thus, an alternative type of simulation is created in this thesis: a simulation based on abacus. It is composed of a finite elements model, that allows heat maps generation for standards cases of heating and cooling. These heat maps are then transformed in abacus. The simulation algorithm based on abacus search the nearest abacus from the simulated situation in order to estimate the temperatures at the next time step.This simulation method was used to reduce the calculation time while keeping a sufficient precision to optimize process parameters.With the simulation based on abacus, a tool for the optimization of melting strategies is developed. This tool allows quality improvement for the produced parts through the calculation of melting strategies according to thermic criteria.To summarize, the main contributions of this work are:- the definition of requirements specifications of a powerful numerical chain for the EBM process- the development of a CAM environment adapted to the EBM process- the proposal of a fast simulation for the EBM process, based on abacus- the development of a tool for the optimization of melting strategies
Schryve, Mathieu. "Modèle d’adhésion cicatrisante et applications au contact verre/élastomère". Aix-Marseille 1, 2008. http://www.theses.fr/2008AIX11091.
Pełny tekst źródłaMany problems encountered in industry are concerned with interface evolutions, where contact, friction and adhesion are fundamental topics. This PhD thesis contributes to the development of a model involving adhesion and friction and allowing the healing of the adhesive bonds when the bodies are again pushed closer together after their separation. This model is called model of healing adhesion. In this work the applications concern specifically the contact glass/rubber. The formation of the the adhesion neck, jump-on and jump-off phenomena and the formation and the propagation of the Schallamach waves are investigated. A modelling of the adhesive contact is thus proposed, based on thermodynamic considerations and surface interactions concepts. In addition to the possible healing of the adhesives bonds, the originality of the model is that healing process and damage process are both related to the rate of the solicitation at the interface. According to the applications, the approch allows to consider two potential sources of dissipation. One is called surface dissipation and linked to the behaviour of the interface. The second is called bulk dissipation and linked to the behaviour of the bodies. The dynamic formulation is done within the framework of the non-smooth mechanic. Implementations of appropriate numerical methods and simulations are done in LMGC90 (Montpellier - Marseille). The model is tested with Benchmark and validated with the simulation of a glass/rubber experiment
Krichen, Abdelkader. "Simulation numérique et analyse expérimentale du comportement d'un contact verre/PMMA sous sollicitations de fretting". Ecully, Ecole centrale de Lyon, 1997. http://www.theses.fr/1997ECDL0021.
Pełny tekst źródłaNguyen, Hoang Quan. "Modélisation et simulation du remplissage de moules verriers : "Prise en compte du transfert radiatif"". Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL054N/document.
Pełny tekst źródłaThe aim of this study is to propose an adapted model for the simulation of mould filling that must be a compromise solution between computational time and results accuracy. The double difficulty is to take into account the filling phenomenon that is a complex problem due to the presence of free boundaries and to the Glass specificities: viscosity that is highly thermal dependant and high melting temperature that requires taking into account radiation effects. Chapter I is devoted to the melting Glass flow. The numerical libraries Aquilon/Thétis, adapted for solving such type of problems and the thermal coupling between Air/Glass/Walls, has been used. (V.O.F method for front tracking, Augmented Lagrangian/Vector Projection methods for solving Pressure/Velocity coupling). For radiative aspect, different approaches are proposed: equivalent radiative conductivity (Chapter II), direct explicit method for validation (Chapter III) and spherical harmonics method or PN method (Chapter IV). In the Chapter V, the selected PN method is validated through simple cases and is then applied in other cases with convective coupling in complex geometries including semi-transparent inclusions (1D, 2D and 3D, 2D axi-symmetric and non grey medium). A P1 modified version is presented. The results are close to those given by P3 method but with reduced computational time. The main interest of this model is that it can be easily implemented in existing numerical codes: a single stationary second order partial differential equation to solve in 3D
Cobilici, Toma Cristina Gabriela. "Conception des engrenages face : simulation de la fabrication et du fonctionnement". Lyon, INSA, 1997. http://www.theses.fr/1997ISAL0067.
Pełny tekst źródłaThe principle of the face gear drives is known since along time : a cylindrical pinion drives a face wheel, the axis of rotation are intersecting or non-intersecting with an off-set, the angle axis can be 90°_Today, in the aeronautical applications, the principal advantage of this mechanism is the translation possibility of the cylindrical pinion without blocking the system. Consequently, the problem consists ta define precisely the real geometry of these drives and moreover to simulate the kinematic meshing to know the influence of the defining parameters. A bibliographical study of the definition and the simulation of these drives, has permitted to choose a set of numerical methods more capable to investigate the variations of the manufacturing parameters. The generation principles of the tooth surfaces remaining the same, the numerical simulation has permitted to define the general tooth profile. Then, the trajectories of the pinion shaper approached with the help of Cubic Splines Normalised, has permitted to study in details two phenomena: pointing and undercutting. Then, the meshing simulation of the numerical tooth geometry outcome from generation, has permitted to define the contact path. The numerical simulation of the meshing has also permitted to obtain the transmission error and the contact ratio. • After qualifying the numerical results with the literature's results, a study of the parameter influence has been realized (the pinion-shaper geometry, pressure angle, mounting position of the driving pinion). The principal conclusion can be briefly resumed in the following manner, the kinematic error is very few modified when small variations of mounting position occurs, even how the contact path are translated. The face gears drives should thus replace the bevel spiral-gears classically used
Lovas, Laszlo Rigal Jean-François Marialigeti Janos. "Etude des relations entre le comportement et la fabrication des synchronisateurs des boîtes de vitesses manuelles". Villeurbanne : Doc'INSA, 2005. http://docinsa.insa-lyon.fr/these/pont.php?id=lovas.
Pełny tekst źródłaBoudiba, Mahfoud. "Contribution à la réalisation d'un environnement général pour la simulation statique des procédés". Paris 13, 1996. http://www.theses.fr/1996PA132035.
Pełny tekst źródłaCicco, Ange de. "Modélisation informatique des conditions de fabrication du fromage corse afin d’établir le processus d’affinage pour obtenir un produit donné". Corte, 2005. http://www.theses.fr/2005CORTA001.
Pełny tekst źródłaPanaït, Adrian. "Étude expérimentale et numérique des problèmes de contact unilatéral et de frottement sec dans les assemblages verriers". Université de Marne-la-Vallée, 2004. http://www.theses.fr/2004MARN0198.
Pełny tekst źródłaThe use of glass as structural material can still be considered as an innovative building technique. Glass elements and especially large dimensions glass facades were realised using assembling systems whose mechanical behaviour has not been well understood. The objective of this work is twofold. Firstly, it consists in systematically seizing and modelling the mechanical behaviour of spliced glass connections transmitting tangential loads by friction. Then, it aims at providing an efficient tool for the design and optimization of spliced glass connections. The resulting mechanical problems are complex because highly nonlinear phenomena such as unilateral contact and dry friction are involved. To achieve the objective, a coupled, experimental and numerical, approach is developped in this work. In a typical spliced glass connection, soft aluminum pads are used as inserts between metallic splice plates and glass plates. A precise characterization of the friction between aluminum and glass is then the key both to ensure the safety and the well functioning of such an assembling system. To this end, an original tribometer is designed and constructed and systematic tests are performed. The weak standard deviation of the results makes it possible to precisely identify the sliding limit and quantify the frictional coefficient variation with the contact duration and the normal loading path. This variation can raise up to 65-70% of the initial friction coefficient and is modelled with an internal variable. A micromechanical interpretation accouting for the asperity creep and highly adhesive area contributions is also given in order to physically explain this variation. The unilateral frictional contact problem posed by a spliced glass connection is numerically solved using the MSC MARC finite element code in which the friction law proposed and identified on the basis of the experimental investigation is implemented. The numerical simulations, validated by full scale tests, provide the stresses and contact pressure due to the combined action of the bolt’s tightening and an tangential loading. The contact area evolution and the co-existence of slip and adhesion zones inside the contact area are identified and shown to be in good agreement with existing theoretical results. Henceforth, this work makes it possible to approach the design and optimisation of spliced glass connections in a rational way instead of the empirical one that has prevailed up to now
Bozek, Sébastien. "Génération de maillage automatique pour la simulation tridimentionnelle de procédés de fabrication de circuits intégrés". Lille 1, 2000. http://www.theses.fr/2000LIL10057.
Pełny tekst źródłaMareel, Delphine. "Amélioration des propriétés optiques des fibres de verre utilisées en télécommunication". Paris, ENMP, 2005. http://www.theses.fr/2005ENMP1439.
Pełny tekst źródłaThe optical fibres are very much used in telecommunication. The study of the manufactoring process of these glass fibres is very important taking into account qualities of transmission which one wants to obtain. This study presents the modeling of the manufactoring process of glass fibres. A first model 1D is the support of a linear analysis of stability. This one makes it possible to predict the appearance of hydrodynamic instabilities during fibre drawing. We will show the influence of the conditions of manufacture on the stability of the process. A second model, 3D this one, makes it possible to make direct simulation thanks to the Rem3D software (developed by the CEMEF). Because of the strong rates of drawing imposed on fibre, the variations of diameter are very important thus the use of the adaptation of grid is essential to obtaining useable results. We present in this thesis the method of adaptation of grid used in the code and the advantages of its use. The difficulties of simulation are on the one hand that the material is multi-layer what was taken into account in this work. In addition, the thermal properties of glass utilize terms of radiation in the enclosure of furnace which are particularly difficult to model. This thesis highlights these difficulty of modeling and thus of integration in the code of heat exchange. The results presented take into account a coefficient of heat exchange are equivalent based on experimental statements. Simulation can still be improved but the results are very encouraging
Lovas, Laszlo. "Etude des relations entre le comportement et la fabrication des synchronisateurs des boîtes de vitesses manuelles". Lyon, INSA, 2004. http://theses.insa-lyon.fr/publication/2004ISAL0017/these.pdf.
Pełny tekst źródłaSynchronizers allow gear changing in manual gearboxes. Their structure, their behaviour as well as problems of behaviour are presented using the Borg-Warner type synchroniser. Mathematical models of phenomena which can be used for description of the behaviour are collected, and then included in numerical simulation software. Simulation results, compared to measured data on synchronizer test rig, allow explaining reasons of the double bump, key phenomenon for the feel of gear changing. Then, simulations highlight the importance of the dynamical behaviour of the synchronizer. Stick-slip, as a main component of the internal excitation, determines the moment of the end of the indexing phase. Discussion of the results permits to suggest improvements of practical use
Deloule, Françoise. "Aide à la conception d'un atelier flexible : modélisation - simulation - dimensionnement". Lyon, INSA, 1987. http://www.theses.fr/1987ISAL0058.
Pełny tekst źródłaThe flexible manufacturing system is a production concept indispensable for the enterprise which wants to stay competitive. A Flexible Manufacturing System consists of three sub-systems : physical system, information system and pilot system. It's conception is complex. First, we have surveyed the existing methods and tools used in the different phases of it s elaboration from the different view points. We have chosen the method MERISE as a conception tool because it is adequate for the problems of Flexible Manufacturing System. In the second time, we have centred our research on the evaluation of parameters of the physical system of the workshop. It' s product capacity, in term of quantity , quality and rapidity of product elaboration, depends on these parameters. Modelling and Simulation seem to be indispensable and comp elementary to solve the problem and to answer the complex problem given by the impact of the variation of the different parameters. On the other side, they permit to define the required specification elements for the choices of machines. We propose also a structured process for the best use of simulation and evaluation of parameters in order to obtain a correct and optimal solution according to some criteria. It brings a considerable contribution in conception of Flexible Manufacturing System
Caprion, Didier. "Etude de verres modèles par dynamique moléculaire : structure et dynamique". Montpellier 2, 1998. http://www.theses.fr/1998MON20086.
Pełny tekst źródłaIssa, Mazen. "Modélisation et simulation numérique des procédés de fabrication sous conditions extrêmes". Troyes, 2010. http://www.theses.fr/2010TROY0004.
Pełny tekst źródłaThis thesis proposes a methodology for numerical modelling and numerical optimization of high speed manufacturing processes. This numerical methodology is based on a thermo-elasto-visco-plastic model with mixed hardening (kinematic and isotropic) and different levels of coupling effects of damage and thermal softening. For this study, we investigated the sensitivity of coulomb friction coefficient on the thermomechanical behaviour. A dynamic explicit resolution scheme has been chosen to solve the equilibrium problem and an implicit integration scheme is used to solve the local behaviour model. To overcome the mesh distortions problems and simulate the propagation of cracks, a numerical methodology based on steps of remeshing is proposed. Different error estimators are used to adjust the size of the elements according to various thermomechanical gradients (cumulative plastic deformation, damage, plastic dissipation) to enhance the effects of localization and evolution of various shear bands. This methodology is studied and validated on various simple examples and on the case of high speeds industrial process simulation
Moura, Luis Mauro. "Identification des propriétés radiatives des matériaux semi-transparents diffusants en situation de non-symétrie azimutale du champ radiatif". Lyon, INSA, 1998. http://theses.insa-lyon.fr/publication/1998ISAL0059/these.pdf.
Pełny tekst źródłaThis work is focused on identification methodology for thermal radiation properties of dispersed media with non-azimuthal symmetry of the radiation field. The properties identified are the optical thickness, the albedo and three parameters of the phase function. The radiative transfer equation is solved numerically by a finite volume discrete ordinate method. A new non-azimuthally quadrature is proposed. The ad hoc quadrature allows the experimental directional measurement considerations. The experimental device is the combination of Fourier transform infrared spectrometer and a goniometer device which allows the bidirectional transmittance and reflectance measurements. The radiative properties have been determined by the minimisation of the quadratic error between the measured and calculated bidirectional transmittances and reflectances. Measurements are performed for oblique incident beam in the range from 0 and 40 degrees. Results are presented to fiber glass and foam insulation in the 1,5 µm to 15 µm wave
Benzaoui, Abderrahmane. "Simulation numérique des écoulements de Poiseuille-Rayleigh-Bénard : application aux procédés de fabrication de couches minces par CVD". Université de Marne-la-Vallée, 2006. http://www.theses.fr/2006MARN0323.
Pełny tekst źródłaWe propose a numerical study of Poiseuille-Rayleigh-Bénard flows (mixed convection in horizontal rectangular channel heated from below). We study in particular the longitudinal and wavy thermoconvective roll patterns. We show that wavy rolls are rarely observed in experiments because they are a convective instability of longitudinal rolls. We finely analyse the influence of sinusoidal and random mechanical excitations on the development and on the dynamic of the wavy rolls. The influence of these thermoconvective flows on the shape of the deposited films in the rectangular thermal CVD reactors is studied. We show that the presence of the wavy or chaotic roll patterns in these reactors improve the uniformity of the deposited film. This study is carried out using a numerical code that solves the 3D Navier-Stokes equations, for a binary mixture, with a reactive wall condition to simulate the depositions
Nicolas, Cyril. "Développement d’une méthode pour qualifier la déformation d’un produit issu d’un traitement thermique : approche experimentale et numérique". Paris, ENSAM, 2009. http://www.theses.fr/2009ENAM0018.
Pełny tekst źródłaNowadays, heat treatment distortion is still difficult to control because of the lack in the corresponding mechanisms comprehension. Indeed, many technological and physical parameters are involved in the distortion formation and evolution, their coupled effects influencing the final results in a complex manner. In this context, the developed method defines a background suitable to study the influences of all parameters on a part distortion. This method is threefold. One point refers to the distortion significant components identification related to specific 3D part geometry: “distortion phenomena”. They are quantified and their accuracy is evaluated using reliability indicators. The second point concerns the comparison of the experimental results with the numerical simulation ones. The numerical simulation prediction of the distortion is investigated by comparing the magnitudes of the distortion significant components. The third point is focused on the distortion mechanisms comprehension. The thermal, metallurgical and mechanical effects on each “distortion phenomenon” magnitude are examined in order to dissociate their influences on the final distortion results. Applied to the C-ring specimen, the developed method allows us to analyze the influence of two parameters on distortion: steel grade and quenching media. Two categories of "distortion phenomena" were detached: homogeneous dimensional variation due to the thermomechanical effects and heterogeneous dimensional variation due to the metallurgical and mechanical effects. Furthermore, the method was adapted to the analysis of numerical simulation results. Thus, distortion numerical simulation results were compared to the experimental ones. A good prediction is obtained for the distortion significant components, even for the local ones. Investigating the numerical simulation results allowed us to understand the distortion mechanisms and to highlight the strong sensibility of some “distortion phenomena” to the experimental parameters variation, used as initial data for simulation
Grégoire, Sébastien. "Identification du coefficient de transfert de chaleur à l'interface verre-outils de formage et prise en compte dans la modélisation par éléments finis des procédés de formage de verre". Valenciennes, 2006. http://ged.univ-valenciennes.fr/nuxeo/site/esupversions/1a90a845-753e-4c73-ac24-b96061e4a3e2.
Pełny tekst źródłaA laboratory testing is developed to determine the heat transfer coefficient hc between the glass and the forming tools under variable conditions in terms of material properties, pressures, temperatures and lubrication. From the research of the optimal position of the thermocouples inside the punch, the evolution of hc during the first second of contact is identified by inverse method using a non stationary thermal conduction model by Finites Differences method. The development of a contact element allows, in relation with the pressure and the temperature levels, the integration of the identified hc in the simulation of glass forming by Finite Elements Method. One of the original points of this work is the analysis of the impact of lubrication on identified hc and on the temperatures inside glass and inside the forming tools during the forming of a blow-blow and a press-blow process
Barakat, Oussama. "Contribution à la modélisation et à la simulation orientée objet des systèmes flexibles de production". Besançon, 1991. http://www.theses.fr/1991BESA2017.
Pełny tekst źródłaNguyen, Kim Thanh. "Optimisation et conception d’une prothèse de membre inférieur : matériaux, simulations et prototypage". Thesis, université Paris-Saclay, 2021. http://www.theses.fr/2021UPAST046.
Pełny tekst źródłaIt is proposed in this PhD work to develop an optimal design of a prosthetic part suitable for additive fabrication, based on material engineering and structural design, as well as manufacturing and testing/characterization. The objective is to find a way to obtain a functional prosthesis satisfying all the operational requirements in terms of material strength and human/structure matching. Finite element-based simulations will also be carried out to help in the design process.The work focuses first on numerical simulations than on experiments. Today, numerical simulations have developed strongly alongside additive manufacturing and materials science. These new methods make it possible to innovate in the field of prosthesis design. For example, the combination of numerical simulation and optimization associated with the use of innovative materials, allow designing prosthetic systems with the desired properties to cover the degraded functions of the patient.Experimental work is carried out to identify the interaction between the prosthetic socket and the stump. The stump’s contact pressure and the socket’s stress are measured by using the electronic circuit. The prosthetic socket is fabricated by using additive manufacturing technique. The stump model is also designed and manufactured based on additive fabrication and a 1cm-silicone layer is added on the outer surface of the stump.Keyword: FE Simulation, Additive Fabrication, Composites, Optimization
Filion, Guillaume. "Fabrication virtuelle et expérimentale de tubes d'aluminium de formes complexes par hydroformage". Master's thesis, Université Laval, 2011. http://hdl.handle.net/20.500.11794/22228.
Pełny tekst źródłaLi, Chen. "Simulation numérique de la fabrication de composites à renfort fibreux 3D par le procédé d'infusion". Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30168.
Pełny tekst źródłaThe manufacture of composite aeronautical structural parts requires the use of more complex reinforcements, especially the 3D reinforcements. Resin infusion is the key process of Liquid Composites Molding (LCM) which will determine the quality and cost of the parts. The target of this thesis is to develop models at different scales of fibrous network of the reinforcement and to propose a finer numerical simulation of the infusion process. The influence of the 2D and 3D reinforcement structures on the infusion process will be studied at the different scales: micro (intra-tow), meso (inter-tows) and macro (reinforcement, part)
Carle, Marc-André. "Simulation et conception d'heuristiques efficaces pour un problème d'assemblage de planchers". Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25410/25410.pdf.
Pełny tekst źródłaGourichon, Boris. "Analyse expérimentale et modélisation des mécanismes de génération de micro-vides en moulage RTM de composites organiques". Lille 1, 2005. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2005/50376-2005-126.pdf.
Pełny tekst źródłaMatei, Mihaita. "Développement d'outils intégrés pour la fabrication virtuelle de produits en aluminium et en acier par hydroformage de tubes pour l'industrie aéronautique". Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/27857/27857.pdf.
Pełny tekst źródłaRharmaoui, Ahmed. "Contribution à la représentation des objets et des métiers industriels : application à la conception-préparation à la fabrication". Montpellier 2, 1993. http://www.theses.fr/1993MON20201.
Pełny tekst źródłaChabot, Alexia. "Méthodologie de monitoring multiphysique des procédés DED : développement par une démarche expérimentale". Thesis, Ecole centrale de Nantes, 2020. http://www.theses.fr/2020ECDN0022.
Pełny tekst źródłaAdditive Manufacturing (AM) is a promising technology compared to subtractive processes, in terms of cost or freedom of manufacturing functional parts. Among the AM techniques, Laser Metal Deposition (LMD) and Wire-Arc Additive Manufacturing (WAAM), included in the Direct Energy Deposition (DED) processes, manufacture parts by directly melting the material in a layer-by-layer maner. Those processes are currently mainly operated in open-loop. Thus, an acceptable part regarding the specified specifications is often the result of a trial-and-error method. In order to improve DED processes performances and to get rid of this trial-and-error method, monitoring and numerical simulation are the most widely investigated solutions. These PhD works propose a generic multiphysic monitoring methodology, based on four independant control loops which can be operated simultaneously. Those control loops are dedicated to the part temperature, geometry, and structural health, and the Stick Out. In these PhD works, control loops have been mainly implemented on the WAAM process, and a specific attention has been devoted to their developments to ensure their applicability to the LMD process. Concurrent to these monitoring develoments, an evaluation of some existing numerical tools has been conducted, in order to integrate simulation together with monitoring in a manufacturing environement. This PhD project is part of the Joint Laboratory of Marine Techology formed by Naval Group and Centrale Nantes
Touati, Abdellaziz. "Analyse du retrait et réduction des déformations en stéréolithographie". Vandoeuvre-les-Nancy, INPL, 1998. http://www.theses.fr/1998INPL041N.
Pełny tekst źródłaKiba, Téwendé Jean-Etienne Arthur. "Simulation et optimisation du transport automatise dans la fabrication de semi-conducteurs". Thesis, Saint-Etienne, EMSE, 2010. http://www.theses.fr/2010EMSE0582/document.
Pełny tekst źródłaEssential components of all computers, semiconductors are widely used in many sectors. Quick advances in these technologies force a challenging rhythm to manufacturers. Following the Moore’s Law, chip capacity doubles approximately every two years and prices are divided by two. Thus, the increase of the diameter of wafers to 300 mm makes them heavier to transport in lots. Automated Material Handling Systems (AMHS) are an excellent alternative to tackle this problem. Because of the high price of production equipment, the goal is to use production capacity as much as possible while avoiding to keep too much inventory. To reach this goal, it is important that the transportation and storage system ensures that machines do not wait for available lots, and also that lots do not wait for available machines. In the literature, due to the problem complexity (up to 700 steps, re-entrant flows, etc.), the modeling of transportation is made with strong assumptions on the production or vice-versa. However, transport is a service for production. This thesis aims at providing a modeling approach that allows the integration in details transport, production and storage constraints, in order to improve production key indicators. A detailed understanding of the system allows us to build of a discrete event simulation model which is, in our point of view, the best compromise between the necessary level of details and computational times. Finally, through industrial validations, the complete study of the model allows critical parameters of transport management to be analyzed. The results help to get a better understanding of the system and open interesting research perspectives
Chu, Thi-Xuan. "Fabrication et caractérisation de populations de microcapsules avec une technique microfluidique". Compiègne, 2011. http://www.theses.fr/2011COMP1959.
Pełny tekst źródłaWe have developed an inverse analysis method that combines a microfluidic technique with a numerical simulation to determine the shear modulus of microcapsule populations. This method is simple and allows the discrimination between various microcapsule populations made of cross-linked ovalbumin membranes that are fabricated at different physico-chemical conditions (pH and time of reticulation). Our method showed that the mechanical properties of the microcapsule membrane were correlated with the degree of reticulation used during the fabrication. We also designed a microsystem for online fabrication and characterization of microcapsules. The microsystem is divided in three parts. The first part consists of two successive Y junctions (flow-focusing) controlling the droplet fabrication and the injection of the cross-linking agent. The second is a wavy microchannel controlling the reticulation time of the microcapsules. Then, the third part is a cylindrical microchannel that allows online characterization of mechanical properties of the microcapsule membrane. We have shown that the droplet size increased with the flow rate ratio of continuous and dispersed phases, but did not change with the flow rate of the reticulation phase. The online reticulation has been demonstrated by the crinkles on the membranes. Finally, the mechanical properties were extracted successfully demonstrating the potential of our approach
Khemiri, Abdelhak. "Approches pour la vérification et la validation des modèles de production : application à une usine de fabrication de semi-conducteurs". Electronic Thesis or Diss., Aix-Marseille, 2020. http://www.theses.fr/2020AIXM0157.
Pełny tekst źródłaToday, business processes have a central place in organizations and the question of their reliability has attracted increasing attention from both industry and the scientific community. Indeed, an error or malfunction in production models can seriously weaken companies. This risk is amplified by the growing importance of process automation and computerization. Thus, this thesis focuses on issues related to the verification and validation of processes and production models of a manufacturing plant. To meet these needs, two approaches have been proposed in this thesis. The first one aims at improving the informational model of production processes through an approach based on machine learning to discover the rules that correspond to the right configuration of the informational model. An industrialization phase is carried out in a semiconductor manufacturing plant and the results obtained are presented. The second contribution concerns the impact of data in the functional perspective of a business process, which limits the use of traditional verification methods. Thus, we propose an approach that combines discrete-event simulation and model-checking. Simulation allows taking advantage of experts' knowledge in order to identify a subset of states where a given property is more likely to be unsatisfied, allowing model-checking to focus on this subset. The approach is tested and validated on a network on-chip model
Vincent, Marc. "Validation de la simulation de l’astigmatisme : application aux verres progressifs Effect of simulated and real spherical and astigmatism defocus on visual acuity and image quality score Subjective Evaluation of Defocus and Astigmatism Combinations Using Image Simulation in Presbyopes Method of assigning progressive addition lenses based on subjective image quality score". Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASP043.
Pełny tekst źródłaVision through a progressive addition lens is a dynamic process especially in near vision when reading. The wearer is led to look into the side parts of the lens. These areas contain astigmatism, which can be particularly annoying. There are different types of progressive addition lenses that are characterized by a specific distribution of astigmatism around the periphery. The objective, in the long term, would be to allow a selection of progressive addition lenses by presenting the future wearer with simulated images for which he or she would have to give notes related to the quality of the perceived image. Using an optical calculation (i.e., convolution between an object and a point spread function), we can simulate the appearance of an image seen through an optic. The objective of this work is therefore to validate the possibility of simulating vision through a progressive addition lens and to make the link between vision quality and wearer choice. In a first step, we compared the quality of vision through adaptive optics simulating spherical and cylindrical defocus with simulated images showing the same optical defects. A difference in vision quality between 20 (i.e. spherical blur) and 35% (i.e. astigmatic blur) between simulated and optical blur was observed. The simulated blur was always greater than the optical blur. These differences were less than the clinically significant difference. In a second step, we directly used a progressive addition lens. The optical defocus tested were then spherical and cylindrical combinations corresponding to specific points of the progressive addition lens along the horizontal axis passing through the near vision optical center. We considered in the simulation of our images that the subject could accommodate. We observed that accommodation played a role when comparing the optical blur with the simulated blur. Presbyopic subjects appear to be able to produce a low level of accommodation that offsets some of the deleterious effect of astigmatism on image quality. We then set up a full-field progressive addition lens analysis device leading to the choice of a type of progressive lens by different wearers. At the same time, we measured vision quality (i.e., simulated image scoring and visual acuity measurement) along the horizontal axis of near vision for these same subjects. The results of the latter study showed that visual acuity is not a good test for predicting vision quality through progressive lenses; the test only worked for 65% of the subjects. On the contrary, the subjective image scoring test predicted the final design choice for 90% of the subjects. Although the statistical results obtained for the different simulated image conditions show a real difference between the real and simulated conditions, we observe that simulated images taking into account some accommodation (i.e., change of sphere in the simulation) are closer to reality. Accommodation thus seems to play an important role when astigmatism is introduced. The study of accommodation in the presence of astigmatism would make it possible to optimize the simulation of the images
Coste, Christian. "Contribution à la simulation numérique du procédé d'extrusion-soufflage des réservoirs à carburants". Compiègne, 1997. http://www.theses.fr/1997COMP1000.
Pełny tekst źródłaArbeltier, Steven. "Optimisation de dépôts de LIPON par pulvérisation magnétron RadioFréquence pour la fabrication de micro-batteries. Modélisation de l'interaction plasma-surface". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS170/document.
Pełny tekst źródłaThe scale reduction of batteries is a real technological challenge for the near future. These micro-batteries, about ten micrometers thick, are used to supply the power for small sized systems. LIPON is one of the most suitable electrolytes considered for industrial scale production. It is deposited in thin-film by radiofrequency magnetron sputtering of Li₃PO₄ in nitrogen plasma. This thesis is focused on particles behavior in plasma and during deposition. Optical emission spectroscopy and electron density measurements have been performed, to provide data used as input or validation for several numerical models. The first model describes plasma kinetics in the magnetron reactor, as 0D global model, and helps to identify the main chemical species and important reactions. This information has been useful to define a simplified kinetics for the second model, 2D, dealing with the charged species behavior in the plasma and describing target sputtering by ion bombardment. It provides the sputtered areas, ion energy and impinging angle onto the target. These obtained results have been employed in a 3D model that simulates sputtered atoms transport from the target to the substrate and predicting the thin-film features. Some characteristics of the target during sputtering have been highlighted and confirmed by the direct comparison between numerical and experimental results
Parrot, Jérôme. "W.A.M, Wire Additive Manufacturing : champs des possibles et utilisation raisonnée". Thesis, Ecole centrale de Nantes, 2018. http://www.theses.fr/2018ECDN0047/document.
Pełny tekst źródłaIn Additive Manufacturing (AM), three dimensionalobjects are built layer by layer by joining each layer to the previous one. For metal parts, there are three main methods: powder bed, powder depositionand wire deposition. This latter makes optimal use of the material in contrast to other processes, which makes it very interesting industrially. Indeed, with powder,the ratio between powder used and powder meltedis not equal to one, in opposition of the use of wire. In order to ensure the proper melting of the metal, several methods already exist, including the use of lasers or electric arc. This manuscript presents a novel approach of wire deposition using inductive energy for additive manufacturing applications (WIAM). This approach does not make use of a storage of the molten material. Instead, the tip of a metal wire is melted by an induction heating system. Inductive energy is also used to obtain an optimal thermal gradient between the tip of the wire and the substrate or previous layer. Thesis work concerns the development of this approach by a numerical model, and its experimental validation. It shows that the induction heating system is able to melt the tip of the wire and heat the substrate to create suitable deposition. The microstructure of additive manufacturing stainless steel has been studied. These results have been compared with WAM method. It is shown that the induction heating system gives a microstructure with very low porosities and a microstructure without a sudden change of composition. These preliminary results indicate that Wire Induction Additive Manufacturing (WIAM) is likely to a suitable process for AM but it still needs to be developed
Belhaj, Mohamed Moez. "Conception et caractérisation des dispositifs micro-ondes pour la fabrication de circuits à base de graphène". Thesis, Lille 1, 2016. http://www.theses.fr/2016LIL10048/document.
Pełny tekst źródłaThis work was carried out under the project involving GRACY IEMN and other research laboratories: CALISTO and IMS Bordeaux. This manuscript reports a comprehensive overview of studies and advanced conducted as part of this thesis in the Institute of Electronics, Microelectronics and Nanotechnology (IEMN) in CARBON group. The main reflection axis of this work is based on the design, modeling and characterization of active and passive devices on flexible and rigid substrates for the development of new components and electronic circuits with increasingly important performance criteria. During this work, the focus was mainly focused on the essential steps to achieving integrated circuit millimeter wave using coplanar technology by inkjet printing and field effect transistors based on graphene (GFETs). This memory in particular shows the importance and potential of graphene for integration into electronic circuits. In addition, special attention was paid on modeling and characterization techniques related to passive devices on flexible substrates. Therefore, a characterization bench of these elements on flexible substrate has been developed during this thesis to verify and consolidate their behavior experimentally
Chen, Zhou. "Simulation virtuelle des essais de validation pour l'ameublement - meubles à base de plaques". Thesis, Paris Est, 2019. http://www.theses.fr/2019PESC2071.
Pełny tekst źródłaIn furniture industry, the numerical simulation allows the design and optimization of wood-based structures, thus avoiding expensive experimental campaigns. Most of wood-based furniture present some particular features in terms of material properties and geometries. On the one hand, the properties of timber materials (such as particule boards) are strongly heterogeneous and anisotropic. On the other hand, the furniture are often made of simply-shaped elements and then can be represented by an assembly of plates and/or beams. The present work deals with those specific features and presents the identification of the elastic properties of particle boards from digital image correlation (DIC) [Chevalier et al. 2001] as well as the simulation of the mechanical behavior of furniture. First, three-point bending tests based on Timoshenko’s beam theory are performed on different samples cut from a prototype desk for the identification of the material properties using DIC techniques. Secondly, a probabilistic model for the uncertain material parameters is constructed by using the Maximum Entropy (MaxEnt)principle [Soize 2017] combined with a Markov Chain Monte-Carlo (MCMC) method based on Metropolis-Hastings algorithm for generating realizations of the underlying random variables. Thirdly, numerical virtual tests are performed to propagate the uncertainties in the material properties through the model and assess the impact of such variabilities on the response of the structure. Lastly, several real tests were previously conducted on the desk in order to validate the proposed numerical approach. Quite good agreement is observed between the numerical computations and the experimental measurements
Yvars, Pierre-Alain. "Poste de travail du roboticien pour l'étude, la simulation et la reconfiguration des lignes de production flexibles dans l'industrie manufacturière : application aux lignes d'assemblage robotisées d'un grand groupe industriel". Lille 1, 1990. http://www.theses.fr/1990LIL10127.
Pełny tekst źródłaChalal, Malik-Eddine. "Aide à la décision pour la servicisation des PME industrielles : une approche par modélisation et simulation". Thesis, Saint-Etienne, EMSE, 2014. http://www.theses.fr/2014EMSE0754/document.
Pełny tekst źródłaThe ever-continuing evolution of business practices leads the decision-makers to develop strategies based on Innovative approaches. One of them is the transition to a product-services system, called servitization. The main goal of this thesis is to provide a decision support in order to anticipate the performance of a company when different transition management scenarios are implemented. The first step toward this objective is the formalization of a conceptual model of product-service systems. They consist of two subsystems: (i) user-oriented subsystem and (ii) production-oriented subsystem. These subsystems are connected and interdependent. The model developped in the second step of the thesis takes into account this coupling, whose influence on the overall performance of the company is assessed thanks to a discret-event simulation approach. Finally a case study is performed for a french SME (ENVIE) whose line of business is the re-manufacturing of electrical equipment. The analysis results highlight the main areas of improvement for the company, allowing a better transition to a product-service system
Ninarello, Andrea Saverio. "Computer simulations of supercooled liquids near the experimental glass transition". Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTS071/document.
Pełny tekst źródłaUnderstanding the mechanisms that lead to glass formation is one of the open problems for the condensed matter research. Numerous questions remain unanswered, because the tremendous increase of relaxation times during the cooling process prevents the exploration of equilibrium properties of supercooled liquids at very low temperature. Computer simulations of glass-forming liquids are nowadays able to reach equilibrium at temperatures comparable to the Mode-Coupling crossover temperature, which is well above the experimental glass transition temperature. As a consequence, simulations lag eight orders of magnitude behind experiments in terms of equilibration times. Progress to close this gap has been slow, and stems mostly from hardware improvements.In this thesis we make an important step to close this gap. We combine the use of a Monte Carlo algorithm, known as the swap algorithm, with the design of novel glass-forming models. We systematically test numerous models using both discrete mixtures and polydisperse systems. We discuss the role that polydispersity and particle softness play in avoiding crystallization and in efficiently reaching previously unexplored regimes. We study the dynamical processes taking place during swap Monte Carlo simulations. We demonstrate that in some cases our technique is able to produce thermalized configurations at temperatures inaccessible even by experiments.In this newly accessible regime, we investigate some open questions concerning the glass transition. We show that a hard sphere fluid can be equilibrated at, and even beyond, the jamming packing fraction. We measure the configurational entropy in extremely supercooled liquid, finding a strong dimensional dependence that supports, on the one hand, the existence of an ideal glass transition at a finite temperature in three dimensions and, on the other hand, its absence in two dimensions. We detect the increase of amorphous order quantified through a static point-to-set length throughout the glass formation. We measure the critical exponents introduced in the mean-field theory of glasses much closer to the supposed ideal glass transition. Finally, we reveal the absence of a sharp geometric transition in the potential energy landscape across the Mode-Coupling crossover.The models and the algorithms developed in this thesis shift the computational studies of glass-forming liquids to an entirely new territory, which should help to close the gap between theory and experiments, and get us closer to solve the long-standing problem of the glass transition
Caruyer, Céline. "Modélisation de nanomatériaux injectés par voie liquide dans un jet de plasma pour la fabrication de nanostructures". Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14329/document.
Pełny tekst źródłaThe study of the plasma spraying process is investigated in this work, in particular the interaction between a liquid phase and a plasma flow. Different physical phenomena occureas the jet fragmentation, the liquid vaporization and the particles fusion. The numerical simulation is used to better understand the physical phenomena and is an alternative to experimental measurements, which could be locally difficult to perform because of the measurement techniques limitations and the particular characteristics of the plasma. A compressible two-phase model is developped to take into account the compressible effects of the plasma flow. Validations are realized on academic test cases and on a argonjet. Good agreements are obtained between simulations and theory or experiments. Then different mixtures of plasmagen gas, classically used in plasma spraying, are studied :argon/hydrogen and argon/helium. An analysis of unsteady and turbulent character isled and allows seeing the importance of unsteady effects in these flows. Numerical simulations of the injection of a liquid phase into the plasma flow are realized. The influence of the plasmagen gas nature and the injection type is anlysed. Structures observed by experiments are also obtained by the simulations
Seignez, Nicolas. "Nano-structures et mécanismes d'altération d'un vitrifiat issu de la métallurgie du plomb : similitudes et spécificités vis-à-vis de matériaux vitreux d'origine industrielle et naturelle". Lille 1, 2006. https://ori-nuxeo.univ-lille1.fr/nuxeo/site/esupversions/0f9b049c-67ae-4eb1-9e1f-bdcf6cf0284e.
Pełny tekst źródłaAgouzoul, Asmaâ. "Nouvelles méthodes numériques pour la simulation de l’impression 3D métallique". Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0004.
Pełny tekst źródłaSelective Laser Melting offers new perspectives in terms of part design and simplification of complex assemblies. However, severe thermo-mechanical conditions arise and are responsible for local plastic deformation, residual stresses and distortion of the manufactured component. Numerical simulation is an interesting tool for process understanding the physical phenomena and their impact on the quality of the part. In this thesis, we propose different approaches to perform simulations at a lower cost, by using model reduction algorithms. The results are compared with those obtained by the finite element method. A reverse analysis in order to identify the inherent strain responsible for the measured elastic springback makes possible to build offline numerical abacus. Therefore, we use a multi-parametric reduced order model using the so called Proper Generalised Decomposition (PGD) to construct this abacus. We also explore the benefits of an implementation of PGD on GPU
Zeramdini, Bessam. "Apport des méthodes de remaillage pour la simulation de champs localisés. Validation en usinage par corrélation d’images". Thesis, Paris, ENSAM, 2018. http://www.theses.fr/2018ENAM0051/document.
Pełny tekst źródłaIn this work, a fully automated adaptive remeshing strategy, based on a tetrahedral element to simulate various 3D metal forming processes, was proposed. The aim of this work is to solve problems associated with the severe mesh distortion that occurs during the computation and which may be incompatible with the evolution of the physical behavior of the FE solution. Indeed, the quality of the mesh conditions affects the accuracy of the calculations. The proposed strategy is integrated in a computational platform which integrates a finite element solver (Abaqus/Explicit), 3D mesh generation and a field transfer algorithm.The base idea is to use the h-adaptive methodology in the combination with a damage-criterion error and Zienkiewicz-Zhu Z2 type error estimator (SPR-improved) to locally control the mesh modification-as-needed. Once a new mesh is generated, all history-dependent variables need to be carefully transferred between subsequent meshes. Therefore, different transfer techniques are described and compared. An important part of this work concerns the presentation of the proposed modification of the field transfer operator and a special attention is given to restore the local mechanical equilibrium of the system. During the large elasto-plastic deformation simulation with damage, the necessary steps for remeshing the mechanical structure are presented. The several types of applications are also given. For all studied applications, the above strategy can improve the accuracy and quality of numerical results. It also has benefits to decide how refined a mesh needs to be to reach a particular level of accuracy, or how coarse the mesh can be without unacceptably impacting solution accuracy.For the machining processes, kinematic field measurements using Digital image Correlation were performed to validate the numerical simulation at the local level. The comparison of the experimental kinematic fields and those resulting from the FE calculation highlights the robustness of the proposed mesh adaptation process which can transcribe the experimental local phenomena. Also, the reproduction of the material flow at the edges and the chip are correlated with the experimental results accurately. Finally, the physical study of the numerical results can be allowed to propose an innovative description of ASB formation
Hergel, Jean. "Synthèse de formes fabricables à partir de spécifications partielles". Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0003/document.
Pełny tekst źródłaThe Rapid Manufacturing techniques that emerged from Rapid Prototyping techniques such as 3D printing or laser cutting allow to fabricate unique objects. However, the design of those objects with existing CAD software remain a difficult task: rapid prototyping processes impose constraints on the geometry of the model. This thesis presents a set of techniques that assist the user in the design of an object by taking into account the constraints of the fabrication process. To achieve this, the algorithm automatically performs part of the modelling process. The following problems have been tackled: First, I propose to improve the quality of 3D printed objects by minimizing defects that appear during the fabrication. The technique developed impacts only the algorithm that drives the printer. Then, I propose to help the user to take into account the fabrication constraints during the modelling process. My techniques rely on partial information about the shape that the user wants to fabricate like the 2D sketch of a mechanism or a parametric model of a furniture. The algorithm optimizes the initial shape to improve fabrication objectives(Wastage, etc.) Finally, in some cases, the user does not know how to operate dedicated software. In this case, I propose a synthesis technique of furniture from functionnal specification, e.g. loads that have to be supported in space
Abouelala, Mourad. "Évaluation des outils de modélisation et de simulation dans le domaine de l’enseignement de la fabrication mécanique : cas des logiciels de la FAO". Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM3056/document.
Pełny tekst źródłaSimulation tools as means to facilitate setting up a production have become very common in industry and, therefore, in education. Among several significant problems, like pedagogical issues, the cost of equipment acquisition and the adaptability of students to the multitude of Computer-Aided Manufacturing, it is raise in education the problem of selecting software in order to ensure maximum effectiveness of teaching process and students learning.This research study was designed to investigate a methodology to select CAM software that could be effective as a support of CAM learning in university, taking into account different features of CAM learning. We determine the student effectiveness in learning factors of CAM software and further, determine the relationship between the different main factors. The research was conducted using a questionnaire submitted to 50 students attending the second academic year of Mechanical Design and Production. The study provides results from empirical test of these relationships and provides criteria for evaluation simulation of software in education
Francioso, Pierre-Arnaud. "Détermination de la résistance thermique d'une interface cristal/amorphe à l'aide de la dynamique moléculaire classique". Thesis, Lille 1, 2014. http://www.theses.fr/2014LIL10210/document.
Pełny tekst źródłaSince the 60s, the history of crystalline silicon cSi and its oxyde (silica, aSiO2) is driven by the emergence of the new transistors. The miniaturization of these technologies, which enabled an increase in computers performances closely related to the Moore law, implies nowadays a nanometric scale comprehension of the physics in these systems. Because of the important costs of nanoscale experiments, numerical simulations and especially molecular dynamics (MD) are often used as a first-choice tool to investigate this kind of problems. In this thesis, we also apply classical MD to the case of silicon-on-insulator (SOI) transistors in order to determine the Kapitza resistance of a cSi-aSiO2 interface, which could be a source of slowdown for the thermal dissipation in ultra thin body and box (UTB²) transistors. We first expose the principle of classical MD (chapter 1) and show some ideas to optimize the neighbour search algorithms (chapter 2). In chapter 3 we explain the steps to form our silicon-silica systems and propose a way to characterize the interface. Finally, in chapter 4 we develop a method – called approach-to-equilibrium molecular dynamics (AEMD) – which allows us to estimate the value of the interfacial resistance interface to be 3.6*10-10 m2.K.W-1