Neste trabalho foram realizadas algumas deposições de filmes de Nitreto de Titânio sobre substrato de aço inoxidável. Foi utilizado o processo conhecido como triodo magnetron sputtering. Os parâmetros de deposição foram mantidos entre as deposições, exceto pela voltagem de bias no substrato, que foi variada de uma deposição para outra. Medições in-situ das tensões residuais no filme depositado foram realizadas. As medições foram feitas através do método da curvatura do substrato, utilizando-se um sensor capacitivo posicionado dentro da câmara de deposição. Embora o dispositivo não tenha sido capaz de quantificar os valores de tensão, foi possível identificar a natureza das mesmas, indicando se elas são de caráter trativo ou compressivo. Comprovou-se a possibilidade do uso de sistemas capacitivos para medições em sputtering. Observou-se que os filmes depositados apresentaram tensões de caráter trativo durante as deposições. / In this work, a series of depositions of titanium nitride thin films was conducted in a triode unbalanced magnetron sputtering chamber. Similar parameters were selected during each deposition, except for the substrate bias voltage, which was different for every deposition. An in-situ measurement of film residual stresses was carried out as the depositions proceeded. This measurement was based on substrate curvature, which was assessed by a home-built capacitive sensor positioned inside the sputtering chamber. Although the measurement device was not able to quantify the stress values, it was possible to identify if they were tensile or compressive. It was proved the possibility of using capacitive measurement devices in sputtering processes. It was possible to observe that the films underwent tensile stresses during the deposition.

The work presented in this Doctoral dissertation concerns the ability of heavy timber structures to passively reduce the fluctuations of the indoor temperature and of the indoor relative humidity, through the dynamic process of heat and moisture storage in wood. We make the hypothesis that the potential offered by the hygrothermal inertia of heavy timber structures is significant, and that it could provide a passive way of regulating the indoor climate. This ultimately could results in a decrease of the energy demand from the Heating, Ventilating and Air Conditioning systems. In this Thesis, the author tries to characterise and quantify the significance of the hygrothermal inertia providing by the heavy timber constructions. The experimental studies contain an in-situ measurement campaign carried out at the Vetenskapsstaden building located in Stockholm and erected in 2001. The results from the test campaign show that a heavy timber construction may contribute to buffer the indoor temperature. A direct quantification of the moisture stored in the wood structure is measured regarding the year-to-year indoor humidity fluctuations. It was however hardly possible to directly quantify the moisture storage potential offered by the structure regarding the day-to-day indoor relative humidity fluctuations because of the low sensitivity of the measuring technique used. In regard to the limitations noticed during the in-situ measurements, laboratory measurements were launched to develop new methods to determine the day-to-day hygric performances of wood exposed indoor. A new method based on the Magnetic Resonance Imaging technology was developed and is intended to provide information about the Moisture Buffer Value measured according to a NORDTEST protocol, and about the moisture distribution in wood with high spatial resolution. The Moisture Buffer Value of untreated Scots pine measured with this method is in accordance with the gravimetric method provided by the NORDTEST protocol. The Moisture Buffer Value of coated Scots pine was also investigated and it is normally assumed that any coatings will decrease the Moisture Buffering Capacity of the structure. The results show however that for specific coating such as waterborne alkali silicate coating, the Moisture Buffering Capacity of the structure may on the contrary be improved. At last, numerical simulations were carried out. They were based upon the extension of a modular simulation environment IDA ICE 3.0, with the implementation of a specific model for heat and moisture transport in a wood. The results obtained pinpoint the highly synergetic effects between the indoor moisture loads, the ventilation rate, the outdoor climate and the moisture interactions with the structure. The outcomes also show that the Moisture Buffering Capacity of a heavy timber structure is appreciable. The structure is able to even out substantially the day-to-day indoor relative humidity fluctuations for a certain range of ventilation rate. / QC 20100825

Neste trabalho foram realizadas algumas deposições de filmes de Nitreto de Titânio sobre substrato de aço inoxidável. Foi utilizado o processo conhecido como triodo magnetron sputtering. Os parâmetros de deposição foram mantidos entre as deposições, exceto pela voltagem de bias no substrato, que foi variada de uma deposição para outra. Medições in-situ das tensões residuais no filme depositado foram realizadas. As medições foram feitas através do método da curvatura do substrato, utilizando-se um sensor capacitivo posicionado dentro da câmara de deposição. Embora o dispositivo não tenha sido capaz de quantificar os valores de tensão, foi possível identificar a natureza das mesmas, indicando se elas são de caráter trativo ou compressivo. Comprovou-se a possibilidade do uso de sistemas capacitivos para medições em sputtering. Observou-se que os filmes depositados apresentaram tensões de caráter trativo durante as deposições. / In this work, a series of depositions of titanium nitride thin films was conducted in a triode unbalanced magnetron sputtering chamber. Similar parameters were selected during each deposition, except for the substrate bias voltage, which was different for every deposition. An in-situ measurement of film residual stresses was carried out as the depositions proceeded. This measurement was based on substrate curvature, which was assessed by a home-built capacitive sensor positioned inside the sputtering chamber. Although the measurement device was not able to quantify the stress values, it was possible to identify if they were tensile or compressive. It was proved the possibility of using capacitive measurement devices in sputtering processes. It was possible to observe that the films underwent tensile stresses during the deposition.

Identifier et caractériser les effets du réchauffement climatique est un des grands enjeux scientifiques de ce début de siècle. Élévation du niveau des mers, bouleversements hydrologiques sont autant de conséquences de ce phénomène qui conditionnent l’existence de toutes les formes de vie présentes sur Terre. Dû à sa capacité thermique élevée, on estime que 84% de l’énergie développée par le réchauffement climatique est stockée dans les premières couches de l’océan. Il est cependant assez difficile d’évaluer son impact global au cours des 50 dernières années car l’océan ne se réchauffe pas de manière uniforme et l’échantillonnage in-homogène (spatial et temporel) des mesures océanographiques, des erreurs instrumentales (XBT) et des biais relatifs aux processus d’estimation des indicateurs globaux peuvent altérer notre appréciation de l’évolution des paramètres océaniques. Afin de pallier ces difficultés inhérentes à l’exploitation des mesures in situ, nous proposons dans cette thèse une correction empirique des données XBT basée sur l’analyse de profils colocalisés, caractérisée par une fonction parabolique sur l’immersion de la sonde et un terme d’offset thermique. À partir de la base de données corrigée, nous présentons ensuite une méthode originale de création de champs grillés grande échelle s’articulant autour de la reconstruction des modes propres de variabilité (DINEOF). Enfin, nous présentons les principaux résultats issus de ces reconstructions en termes de tendances globales et de variabilité du contenu thermique et contenu d’eau douce. Ces travaux contribuent ainsi à mieux documenter la variabilité océanique dans la couche 0-700m. / To identify and characterize the effects of global warming is one of the major scientific challenges of this new century. The rise of sea level, the hydrological changes are some consequences of this phenomenon which will influence all forms of life on Earth. Due to its high thermal capacity, it is estimated that 84% of the energy developed by global warming is stored in the first layers of the ocean. However, it is rather difficult to assess its overall impact over the last 50 years because the ocean is not warming uniformly and the inhomogeneous sampling (spatial and temporal) of oceanographic observations, instrumental errors (XBT) and biases related to the estimation process of global indicators can affect our assessment of the evolution of ocean parameters. To overcome these difficulties of in situ measurements analysis, we propose here an empirical correction of XBT data based on the analysis of collocated profiles, characterized by a parabolic function of the immersion of the probe and a thermal offset. From the corrected database, we present a new method for creating large-scale gridded fields based on the reconstruction of the natural modes of variability (DINEOF). Finally, we present the main results from these reconstructions in terms of global trends and variability of heat content and freshwater content. This work contributes to better document the oceanic variability in the 0-700m layer.

The dissertation thesis is focused on thermal insulating properties of reflective insulation under boundary conditions typical for low-energy buildings. In the introductory part of this thesis the attention is focused on the heat transfer process. There is described primarily heat transfer by radiation. There is also described the reflective insulation and the methods of determination their thermal performance. The remaining part of the thesis deals with the analysis of the results obtained in experimental measurements. Measurement results are compared with the calculation model. Conclusions for technical practice including possibilities of further research are summarized in the final section.

Pour mieux appréhender les mécanismes de transfert des gaz (CO2 et CH4) dissous dans l’eau porale des formations des marnes du site de Bure et des argiles à Opalinus (AOP) du Mt Terri dans leur état initial, un capteur infrarouge (IRTF) et un banc optique Raman innovant ont été développés et installés en laboratoire souterrain. Ces capteurs sont intégrés au dispositif de l’expérimentation « d’équilibration de gaz » développée par l’Andra (PAC) qui vise à suivre l’évolution d’une phase gazeuse initialement neutre au contact de la formation et de son eau porale grâce à un forage effectué et maintenu dans des conditions anaérobiques. Ces capteurs permettent un suivi quantitatif in situ et en ligne des gaz libérés par la formation à basse pression totale (<1,3 bar). Les modèles quantitatifs développés pour la mesure infrarouge ont une erreur relative moyenne de 1,66 % pour la pCO2 (mbar.m) et de 1,37 % pour la pCH4 (mbar.m). L’instrumentation IR d’un forage sur le site du Mt Terri et de deux forages sur le site de Bure (faciès C2b1 et C2d) a permis d’obtenir les courbes de transfert des deux gaz. Les courbes de transfert du CH4 ont été modélisées par un modèle de diffusion-advection qui ont permis l’évaluation de la concentration locale en CH4 dissous dans l’eau porale : elles sont comprises entre 3,06 et 14,23 mg.L-1 pour les AOP, et entre 0,36 et 1,28 mg.L-1 pour le faciès C2d et entre 0,56 et 1,55 mg.L-1 pour le faciès C2b1 des argilites de Bure. On montre que les équilibres eau/gaz/roche gouvernent la pCO2 après forage alors que la diffusion/advection explique son évolution sur le long terme. Une origine intraformationnelle des alcanes dissous est envisagée / An infrared sensor (IRTF) and an innovative Raman optical bench were implemented and developed in underground laboratories to improve our knowledge about migration mechanisms of dissolved gases (CO2 and CH4). This study is focussed on the characterisation of the initial state of the porewater of Callovo-Oxfordian marl (Bure) and Opalinus Clay (Mt Terri Middle Jurassic). These sensors are integrated into experimental devices of gas-equilibration test developed by Andra (PAC) to follow the gaseous phase behaviour in contact with the rock formation through a borehole drilled and maintained in anaerobic conditions, and initially filled with pure argon. These in situ sensors allow, on line quantitative analysis of gases released by the rock formation at low bulk pressure (<1.3 bar). Quantitative models were developed to transform peak intensities in partial pressures of gas. They give mean absolute relative errors about 1.66 % for pCO2 (mbar.m) and 1.37 % for pCH4 (mbar.m). Three years of IR monitoring of one borehole on the site of Mt Terri and two boreholes on the site of Bure (facies C2b1 and C2d) have been led. CH4 transfer curves were modelled by diffusion-advection. CH4 concentration in porewater from non-perturbed rock formation is estimated from all the experiments: concentrations between 3.06 and 14.23 mg.L-1 was obtained for Opalinus Clay, between 0.36 and 1.28 mg.L-1 for C2d facies and between 0.56 and 1.55 mg.L-1 for C2b1 facies in Callovo-Oxfordian marls of Bure. Gas/rock/water balance governs pCO2 after drilling, whereas diffusion/advection laws explain CO2 long-term profiles. An intra-formational origin of the organic gases can be proposed

La qualité des pièces découpées pour les industries électroniques et micromécaniques est appréciée via trois critères principaux : le niveau de bavure, l’aspect du bord découpé et la précision dimensionnelle. Or, l’étude de la qualité des pièces découpées ne peut se faire sans une compréhension de l’usure des poinçons. Ainsi, des méthodes de mesure en continu et in situ de l’usure ont été mises au point et validées, soit l’activation superficielle et la mesure par double réplique. Ainsi, il a été possible de suivre l’influence d’un certain nombre de paramètres du procédé sur l’évolution de l’usure lors du découpage. Par ailleurs, nous avons mis au point une méthode de quantification de la bavure sur la totalité du contour découpé. Il a ainsi été possible d’étudier l’évolution de la bavure au cours de la découpe. L’aspect des bords découpés a été examiné grâce à des relevés topographiques permettant le suivi de son évolution. Ainsi, une corrélation entre la cinétique d’usure des poinçons et l’apparition de la bavure a été établi. De plus, une simulation expérimentale de l’usure des poinçons a été entreprise. Un dispositif expérimental de tribométrie a été conçu et installé sur la ligne de presse, simulant les conditions de frottement d’un poinçon sur une tôle. Il a permis d’évaluer l’abrasivité des tôlesminces vis-à-vis des poinçons. Par ailleurs, une modélisation numérique de l'opération de découpage par éléments finis a été entreprise, permettant d’approcher le profil d’usure d’un poinçon de géométrie cylindrique. Et par conséquent la possibilité de prédire son évolution en fonction du nombre de pièces découpées devient accessible en fonction des paramètres du procédé / The blanked parts quality for electronic and amicromechanical industry is assessed using threemain criterions: the burr amount, the appearance ofthe cut edge and dimensional accuracy. However, thestudy of the quality of the blanked pieces can not bedone without an understanding of the punches wear.Thus, methods for continuous and in-situ wearmeasurements have been developed and validated:Thin Layer Activation and measurement by doublereplica. Thus, it was possible to follow the influenceof process parameters on the wear evolution duringblanking.In addition, we have developed a method forquantifying the burr on the entire blanked contour. Itwas thus possible to study the evolution of the burrduring blanking. The appearance of the cut edges wasexamined by means of topographic survey for monitoringits evolution. Thus, a correlation between the kinetics ofpunches wear and the appearance of the burr has beenestablished. In addition, an experimental simulation ofpunches wear was undertaken. An experimentaltribometry was designed and installed on the press line,simulating the conditions of friction of a punch on onesheet. It evaluated the abrasiveness of thin sheets againstthe punches.Additionally, a numerical modelling of blanking wasundertaken to approach the wear profile of a punch ofcylindrical geometry. And therefore the ability to predictits evolution contingent on the number of blanked pieces becomes available depending on process parameters

Aujourd'hui, la pompe à chaleur (PAC) est largement utilisée pour les applications de chauffage du bâtiment en raison de ses bonnes performances énergétiques. Elle est même considérée comme une source d'énergie renouvelable et, selon la Directive Européenne 2009/28/CE, la part «renouvelable» de l'énergie produite doit être calculée à partir de la performance annuelle. Il est donc important d'être à même de mesurer cette dernière. Or, il n'existe pas, pour les PAC air/air, de méthode fiable et simple permettant de mesurer la performance chez le client pendant une saison.Dans ce contexte, la thèse propose deux méthodes in situ qui répondent à ce besoin. La première est basée sur des mesures non-intrusives des propriétés du fluide frigorigène. Elle utilise le bilan énergétique du compresseur pour déterminer le débit du fluide. La deuxième, fondée sur les mesures côté air, utilise un ensemble de capteurs à fil chaud afin de mesurer le débit et les températures d'air.La thèse développe également une méthode de mesure intrusive du fluide frigorigène, qui n'est pas adaptée aux conditions in situ mais sert de référence pour valider les deux méthodes in situ. Les résultats expérimentaux montrent que la méthode de référence est précise non seulement en conditions stabilisées mais également en fonctionnement dynamique (y compris lors des dégivrages).La validation des deux méthodes in situ a été réalisée par une campagne d'essais spécifique en laboratoire. Une suite intéressante de la thèse consistera à intégrer la méthode non intrusive côté frigorigène directement dans l'équipement de mesure et d'affichage de la PAC. / Today, heat pumps (HP) are widely used as heating systems in building thanks to their high energy efficiency. They are even considered as a source of renewable energy and, according to the EU Directive 2009/28/EC, the amount of renewable energy has to be calculated from the annual performance. Therefore, it is important to be able to measure the annual performance. However, concerning the air-to-air HP there is no reliable and simple method which allows measuring the performance in situ during at least a season.In this context, the thesis proposes two in situ methods that could fill this gap. The first one is based on non-intrusive measurements on refrigerant side. It uses a compressor energy balance to determine the flow rate. The second one, based on air measurements, uses a distribution of hot-wire sensors to determine the air flow rate and temperatures.The thesis also develops an intrusive refrigerant method, which is not necessarily adapted for in situ conditions but can be used as a reference to validate the in situ methods. The experimental results show that the reference method is accurate both in stationary conditions and in dynamic operations (including during defrosting period).The validation of the in situ methods was performed by a specific test campaign in laboratory. As a perspective, the thesis makes it possible to develop on-board measurement methods using non-intrusive refrigerant sensors, providing an opportunity for manufacturers to display the in situ performance in real time.

Le bruit dû aux infrastructures de transports terrestres fait partie des premières préoccupations environnementales de ce début de 21e siècle. Un moyen utilisé pour réduire ce bruit est de placer des protections acoustiques le long des grands axes routiers et ferroviaires. Actuellement, les choix de ces protections antibruit se portent généralement sur des solutions traditionnelles : écran droit, merlon, écran incliné, écran avec un couronnement. Le but de ce travail est de proposer des protections acoustiques innovantes utilisant des moyens naturels et d’en étudier la performance acoustique en utilisant des approches numériques et expérimentales. L’approche numérique peut être couplée en outre à un outil d’optimisation, développé dans cette thèse, pour chercher des formes améliorées de tels dispositifs antibruit novateurs. Après une présentation des principaux phénomènes mis en jeu dans la propagation des ondes acoustiques en milieu extérieur complexe, un état de l’art des principaux écrans acoustiques dédiés aux transports terrestres a été établi, permettant de choisir trois protections antibruit innovantes pour en étudier la performance acoustique. Une analyse des principales méthodes de simulation numérique, de mesure et d’optimisation des protections antibruit a permis de choisir les méthodes adaptées à notre problématique des écrans acoustiques utilisant des moyens naturels. Les méthodes choisies ont été utilisées dans ce travail pour évaluer la performance acoustique de ces écrans innovants. Pour le premier écran choisi, dit écran en gabions, nous avons effectué des mesures in-situ et sur modèles réduits, ainsi que des simulations numériques montrant une efficacité satisfaisante. Pour le deuxième écran, utilisant des cristaux soniques, et pour le troisième écran, de type merlon acoustique de forme complexe, nous avons réalisé une étude numérique paramétrique suivie d’une étude d’optimisation. Les résultats des calculs ont montré l’intérêt de tels dispositifs antibruit pour réduire le bruit de circulation routière et ferroviaire en milieu urbain et ils ont abouti à des formes améliorées des protections acoustiques utilisant des moyens naturels. / Noise due to ground transportation infrastructures is among the first environmental concerns of this beginning of 21th century. Building noise protections along motorways and railways is usually the chosen solution to reduce this noise. Currently, noise abatement systems used are mainly conventional ones: straight barriers, earth berms, tilted barriers, capped barriers. The purpose of this work is to propose innovative noise barriers using natural means and to study their acoustic performance by using numerical and experimental approaches. The numerical approach can also be coupled with an optimization tool, developed in this thesis, to obtain improved shapes of such devices using natural means. First, the main phenomena that appear during acoustic wave propagation in a complex outdoor medium are described. Then, a state of the art of the main noise barriers dedicated to ground transportation noise is achieved. It drives the choice of three innovative noise barriers using natural means. An analysis of the main numerical, experimental and optimization methods is carried out which allows to choose the methods adapted to our problem of noise barriers using natural means. The chosen methods are used in this work to assess the acoustic performance of the three innovative noise barriers. For the first chosen noise barrier called “gabions barrier”, we perform in-situ and scale model measurements and numerical simulations. The results show a satisfactory efficiency of such noise devices. For the second and the third chosen noise barriers called respectively “sonic crystal assisted barrier” and “complex shaped earth berm”, we perform a parametric numerical and an optimization studies. The results show the capacity of such noise devices to reduce motorways and railways noises in urban areas and they lead to improved shapes of innovative noise barriers using natural means.

Doppler radar wind profilers are already widely used to measure atmospheric winds throughout the free troposphere and stratosphere. Several methods have been developed to quantify atmospheric turbulence with such radars, but to date they have remained largely un-tested; this thesis presents the first comprehensive validation of one such method. Conventional in-situ measurements of turbulence have been concentrated in the surface layer, with some aircraft and balloon platforms measuring at higher altitudes on a case study basis. Radars offer the opportunity to measure turbulence near continuously, and at a range of altitudes, to provide the first long term observations of atmospheric turbulence above the surface layer. Two radars were used in this study, a Mesosphere-Stratosphere-Troposphere (MST) radar, at Capel Dewi, West Wales, and the Facility for Ground Based Atmospheric Measurements (FGAM) mobile boundary layer profiler. In-situ measurements were made using aircraft and tethered-balloon borne turbulence probes. The spectral width method was chosen for detailed testing, which uses the width of a radar's Doppler spectrum as a measure of atmospheric velocity variance. Broader Doppler spectra indicate stronger turbulence. To obtain Gaussian Doppler spectra (a requirement of the spectral width method), combination of between five and seven consecutive spectra was required. Individual MST spectra were particularly non-Gaussian, because of the sparse nature of turbulence at its observation altitudes. The width of Gaussian fits to the Doppler spectrum were compared to those from the `raw' spectrum, to ensure that non-atmospheric signals were not measured. Corrections for non-turbulent broadening, such as beam broadening, and signal processing, were investigated. Shear broadening was found to be small, and the errors in its calculation large, so no corrections for wind shear were applied. Beam broadening was found to be the dominant broadening contribution, and also contributed the largest uncertainty to spectral widths. Corrected spectral widths were found to correlate with aircraft measurements for both radars. Observing spectral widths over time periods of 40 and 60 minutes for the boundary layer profiler and MST radar respectively, gave the best measure of turbulence intensity and variability. Median spectral widths gave the best average over that period, with two-sigma limits (where sigma is the standard deviation of spectral widths) giving the best representation of the variability in turbulence. Turbulent kinetic energies were derived from spectral widths; typical boundary layer values were 0.13 m 2.s (-2) with a two-sigma range of 0.04-0.25 m 2.s (-2), and peaked at 0.21 m 2.s (-2) with a two-sigma range of 0.08-0.61 m 2.s (-2). Turbulent kinetic energy dissipation rates were also calculated from spectral widths, requiring radiosonde measurements of atmospheric stability. Dissipation rates compared well width aircraft measurements, reaching peaks of 1x10 (-3) m 2.s (-3) within 200 m of the ground, and decreasing to 1-2x10 (-5) m 2.s (-3) near the boundary layer capping inversion. Typical boundary layer values were between 1-3x10 (-4) m 2.s (-3). Those values are in close agreement with dissipation rates from previous studies.