Thèses sur le sujet « Modèle de transport chimique »
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Dugault, Edouard. « Etude du transport et de l'évolution physico-chimique de masses d'air européennes au-dessus de l'Atlantique Nord sous des conditions anticycloniques ». Paris 6, 2002. http://www.theses.fr/2002PA066518.
Cathala, Marie-Laure. « Assimilation de mesures chimiques d'ozone au niveau de la tropopause dans un modèle de chimie-transport global ». Toulouse 3, 2004. http://www.theses.fr/2004TOU30034.
The tropopause has an important role in atmospheric dynamics and chemical composition which is due to exchanges which take place between two very different regions: troposphere and stratosphere. Strong vertical gradients take place in this region making its representation by numerical chemical-transport models difficult. The aim of this work is to force the numerical simulations with observations in order to obtain a better representation of the ozone fields in this region, in order to make phenomenological studies more realistic. The global scale chemical-transport model used for this purpose is MOCAGE which has been developed in Météo-France. Observations come from the MOZAIC european program, and include measurements of ozone, water vapour and other minor constituents obtained from instruments mounted on commercial aircraft since 1993. .
Muller, Martine. « Contribution à l'étude de dépôts en phase vapeur de semiconducteurs IV-VI par "hot wall epitaxy" : modèle thermodynamique du transport gazeux ». Montpellier 2, 1990. http://www.theses.fr/1990MON20114.
Marinoni, Marianna. « Implémentation des isotopes dans un modèle hydrogéochimique couplé ». Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAH001/document.
The work describes the development of a reactive transport code named SpeCTr (Spéciation Cinétique Transport in French). The code, able to describe isotopic fractionation, is obtained through the coupling of a transport module and a reaction module that describes the main chemical reactions (operator splitting approach). A consistent portion of the work is dedicated to the improvement of the numerical methods employed in the reaction module for solving thermodynamic equilibrium (Newton Raphson method modified with scaling and Positive Continuous Fractions) and mixed equilibrium and kinetic reactions (formulation and solution of systems of differential and differential-algebraic equations). The code was verified through the solution of different benchmarks (batch and reactive transport simulations) and applied to perform 1D, 2D and 3D simulations of laboratory experiments dedicated to calcite crystals dissolution in a column of porous medium
Coopmann, Olivier. « Vers une meilleure assimilation des observations satellitaires infrarouges par le couplage des modèles météorologique et chimique ». Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30303.
The Infrared Atmospheric Sounding Interferometer (IASI) is the instrument that provides the most satellite observations to the ARPEGE (Action de Recherche Petite Échelle Grande Scale) Numerical Weather Prediction (NWP) model at Météo-France. This sensor was developed jointly by CNES (Centre National d'Études Spatiales) and EUMETSAT (European Organisation for the Exploitation of Meteorological Satellites) and is carried on board the Metop-A, B and C polar orbiting satellites. The assimilation of these observations requires the use of a Radiative Transfer Model (RTM) called RTTOV at Météo-France. The latter uses an a priori knowledge of the most likely thermodynamic and chemical state of the atmosphere to simulate IASI observations. At Meteo-France, the background thermodynamic fields come from a short-term forecast provided by ARPEGE but the information on the chemical composition of the atmosphere comes from a single vertical reference profile for each chemical species, provided by RTTOV. However, this approximation has a significant impact on the quality of simulations and the use of infrared satellite observations for NWP. Chemistry Transport Models (CTM) are able to provide forecasts of the chemical composition of the atmosphere. At Météo-France, this CTM is called MOCAGE. This thesis therefore proposes a method toward a better assimilation of infrared satellite observations by coupling meteorological and chemical models. The first part of the work was to evaluate the sensitivity of infrared observations to some atmospheric compounds. To do so, we participated in the APOGEE (Atmospheric Profiles Of GreenhousE gases) measurement campaign, which enabled us to measure in situ profiles of CO2, CH4 and O3. These data were used both to validate the quality of our simulations and as verification data to assess atmospheric chemical composition derived from CTM. We then supervised two Master 1 trainees to carry out an evolving climatology of CO2 in order to improve the use of infrared satellite observations. From these studies, it appears that the quality of the simulations depends on the accuracy of the chemical information used and the chemical component with the greatest impact on the simulations is ozone. Thus, the rest of the thesis work was therefore focused on ozone. A first step was to prepare the assimilation of ozone-sensitive IASI channels. This work has shown both that the use of realistic ozone information from a CTM can better simulate ozone-sensitive observations and provide additional information, simultaneously improving temperature, humidity and ozone analyses [Coopmann et al., 2018]. [...]
Srour, Zainab. « Unravelling the chlorine chemistry using simulations from the molecular scale to the global scale ». Electronic Thesis or Diss., Université de Lille (2022-....), 2023. http://www.theses.fr/2023ULILR038.
The discovery of the ozone hole over the Antarctic in the 1970s established the significance of gas-phase halogenated species in the atmosphere. These species play a crucial role in tropospheric and stratospheric chemistry, influencing ozone budget, atmospheric concentrations of key species (such as OH, NOx, and volatile organic compounds), and halogen interactions. Numerous studies have explored halogen chemistry using global models, however, most of the focus has been on bromine and iodine due to their higher reactivity compared to chlorine. This preference arises from the greater chemical stability of HCl compared to other halogen acids (HX, where X = Br, I).This thesis aims to unravel the chlorine chemistry in the troposphere starting from the molecular up to the global scales. This is done through the employment of different numerical tools: (i) quantum chemistry tools to predict the reactivity and thermokinetic parameters of the reaction between OH radicals and CH2ClOOH, which are challenging to obtain experimentally, (ii) the kinetic model “ASTEC” to determine the reactivity of gaseous chlorinated compounds on a short time scale; and (iii) the chemistry transport model “MOCAGE” to evaluate the impact of chlorine on the global atmospheric budget.The results show that the reaction between CH2ClOOH and OH radicals is of atmospheric interest with an overall rate constant 6.55 × 10-11 cm3 molecule-1 s-1 at 298 K computed at the M06-2X/6-311++G(3df,3p) level of theory. The kinetic modelling showed that the daytime reactivity of chlorinated compounds is more important than the night-time reactivity governed by photolysis and reactivity with OH radicals. Moreover, the global modelling by MOCAGE showed that the chlorine atmospheric budget is not only affected by chemical transformation, but also, it is altered by the physical processes including transport and deposition
Barré, Jérôme. « Assimilation de données satellites au limbe et au nadir dans un modèle de chimie-transport ». Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0092/document.
Data assimilation combines in an optimal way a numerical model describing the evolution of the atmospheric chemical composition and the available trace gases measurements. In this thesis, data assimilation is used to characterize the ozone (O3) and the carbon monoxide (CO) distributions in the stratosphere and in the troposphere. The Chemistry Transport Model (CTM) MOCAGE (MOdèle de Chimie Atmosphérique à Grande Echelle) is used in a configuration with two nested domains at 2◦ (global) and at 0.2◦ (regional). To perform the assimilation experiments a 3D-FGAT variational method is used. We evaluate the complementarity of limb and nadir measurements available at the present day at characterizing the UTLS (Upper Troposphere Lower Stratosphere) region by assimilating simultaneously the two type of measurements. We particularly focus on the impacts of data assimilation of stratospheric ozone measurements on troposphere and conversely of tropospheric data assimilation on stratosphere. Showing the added value of the increased horizontal resolution in the UTLS assimilated fields and the synergistic effects of limb and nadir assimilation were the main objectives of this work. Development in the assimilation system have been made in the assimilation system with the nested domain. Data assimilation in the global domain is now taken in account and the boundary condition from the assimilated fields show significant impacts on the regional domain. Firstly, we assimilate stratospheric ozone profiles from MLS (Microwave Limb Sounder) to investigate two Stratosphere-Troposphere Exchange (STE) case studies.
Josse, Béatrice. « Représentation des processus de transport et de lessivage pour la modélisation de la composition chimique de l'atmosphère à l'échelle planétaire ». Toulouse 3, 2004. http://www.theses.fr/2004TOU30108.
Bousserez, Nicolas. « Étude du transport intercontinental de la pollution atmosphérique entre l'Amérique du nord et l'Europe à l'aide du modèle de chimie-transport MOCAGE ». Toulouse 3, 2008. http://www.theses.fr/2008TOU30330.
This work aims to characterize the intercontinental transport of pollution between North America and Europe. We focus our study on the summer 2004, using aircraft in situ data from the ICARTT experiment together with simulations from the MOCAGE global chemistry-transport model. In a first part we present an evaluation of the model against in situ measurements over three domains of interest : North-East United States, North Atlantic and Europe. In a second part we analyze the respective impacts of North American biomass burning and anthropogenic plumes on ozone chemistry over the North Atlantic. The last part of our study compares two different modeling strategies to take into account the high space and time variability of biomass burning sources: assimilating daily space-based CO observations into the model and using a daily emission inventory of fire emissions
Praga, Alexis. « Un modèle de transport et de chimie atmosphérique à grande échelle adapté aux calculateurs massivement parallèles ». Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30012/document.
We present in this thesis the development of a large-scale bi-dimensional atmospheric transport scheme designed for parallel architectures with scalability in mind. The current version, named Pangolin, contains a bi-dimensional advection and a simple linear chemistry scheme for stratospheric ozone and will serve as a basis for a future Chemistry Transport Model (CTM). For mass-preservation, a van Leer finite volume scheme was chosen for advection and extended to 2D with operator splitting. To ensure mass preservation, winds are corrected in a preprocessing step. We aim at addressing the "pole issue" of the traditional regular latitude-longitude by presenting a new quasi area-preserving grid mapping the sphere uniformly. The parallelization of the model is based on the advection operator and a custom domain-decomposition algorithm is presented here to attain load-balancing in a message-passing context. To run efficiently on current and future parallel architectures, algebraic features of the grid are exploited in the advection scheme and parallelization algorithm to favor the cheaper costs of flops versus data movement. The model is validated on algebraic test cases and compared to other state-of-theart schemes using a recent benchmark. Pangolin is also compared to the CTM of Météo-France, MOCAGE, using a linear ozone scheme and isentropic coordinates
Amir, Laila. « Modèles couplés en milieux poreux : transport réactif et fractures ». Phd thesis, Paris 9, 2008. https://bu.dauphine.psl.eu/fileviewer/index.php?doc=2008PA090061.
This thesis deals with numerical simulation of coupled models for flow and transport in porous media. We present a new method for coupling chemical reactions and transport by using a Newton-Krylov method, and we also present a model for in fractured media, based on a domain decomposition method that takes into account the case of intersecting fractures. This study is composed of three parts: the first part contains an analysis, and implementation, of various numerical methods for discretizing advection-diffusion problems, in particular by using operator splitting methods. The second part is concerned with a fully coupled method for modeling transport and chemistry problems. The coupled transport-chemistry model is described, after discretization in time, by a system of nonlinear equations. The size of the system, namely the number of grid points times the number a chemical species, precludes a direct solution of the linear system. To alleviate this difficulty, we solve the system by a Newton-Krylov method, so as to avoid forming and factoring the Jacobian matrix. In the last part, we present a model of flow in 3D for intersecting fractures, by using a domain decomposition method. The fractures are treated as interfaces between subdomains. We show existence and uniqueness of the solution, and we validate the model by numerical tests
Amir, Laila. « Modèles couplés en milieux poreux : transport réactif et fractures ». Phd thesis, Université Paris Dauphine - Paris IX, 2008. http://tel.archives-ouvertes.fr/tel-00373688.
Ce travail est divisé en trois parties : la première partie contient une analyse de différents schémas numériques pour la discrétisation des problèmes d'advection-diffusion, notamment par une technique de séparation d'opérateurs, ainsi que leur mise en oeuvre informatique, dans un code industriel.
La deuxième partie, qui est la contribution majeure de cette thèse, est consacrée à la modélisation et à l'implémentation d'une méthode de couplage globale pour le transport réactif. Le système couplé transport-chimie est décrit, après discrétisation en temps, par un système d'équations non linéaires. La taille du système sous-jacent, à savoir le nombre de points de grille multiplié par le nombre d'espèces chimiques, interdit la résolution du système linéaire par une méthode directe. Pour remédier à cette difficulté, nous utilisons une méthode de Newton-Krylov qui évite de former et de factoriser la matrice Jacobienne.
Dans la dernière partie, nous présentons un modèle d'écoulement dans un milieu fracturé tridimensionnel, basé sur une méthode de décomposition de domaine, et qui traite l'intersection des fractures. Nous démontrons l'existence et l'unicité de la solution, et nous validons le modèle par des tests numériques.
Sič, Bojan. « Amélioration de la représentation des aérosols dans un modèle de chimie-transport : modélisation et assimilation de données ». Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2667/.
The main goal of this thesis is to improve the aerosol representation in the CTM MOCAGE. The work may be divided into: the direct improvement of aerosol physical parameterizations, and the development of a data assimilation system able to assimilate aerosol optical depth (AOD) and lidar profiles. On the modelling side, the processes that underwent the important improvements were sea salt, desert dust and volcanic aerosol emissions, wet deposition and sedimentation. The ambition is related to improve the model biases compared to observations, and to implement more physically detailed schemes in the model. We evaluated the impacts of these changes and compared the modelled fields to observations. The implemented updates significantly enhanced the model agreement with the observations and the inter-model comparison data. The results also confirmed that large uncertainties in models can come from the use of different parameterizations. The aerosol data assimilation is implemented to further reduce the model uncertainties. The set of observation operators and their tangent linear and adjoint operators for AOD and lidar profile observations are developed to link the model and the observation space. Aerosol assimilation proved to be very efficient to reduce the differences between the model and the observations. The assimilated AOD observations were able to significantly improve the model performance in terms of AOD and concentrations. Assimilation of lidar measurements: the backscatter signal, the extinction and backscatter coefficients, also showed an efficient influence on the vertical profiles
Ginoux, Paul. « L'impact de l'activité humaine sur la composition chimique de la troposphère au-dessus de l'Océan Pacifique : développement d'un modèle téléscopique de chimie et de transport atmosphériques et interprétation des résultats de la campagne de mesure MLOPEX ». Doctoral thesis, Universite Libre de Bruxelles, 1997. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212164.
De manière à mieux comprendre l'impact des émissions anthropiques sur la troposphère reculée, les concentrations d'un nombre important de composés atmosphériques ont été mesurés dans la troposphère libre au-dessus d'Hawaii durant la campagne Mauna Loa Observatory Photochemistry Experiment (MLOPEX) accomplie au cours des années 1991 et 1992. Le constituant chimique fondamental pour évaluer cet impact est le radical hydroxyle OH qui fut mesuré au printemps et en été de l'année 1992. La variation diurne de la direction du vent génère pendant la journée un mélange des masses d'air de la couche limite planétaire avec la troposphère libre. Actuellement les modèles régional et global de chimie troposphérique ne peuvent tenir compte à la fois du transport à grande échelle et du mélange local. Nous avons développé un modèle tridimensionnel qui nous permet d'analyser la chimie et la dynamique troposphérique à ces deux échelles. Pour ce faire, nous avons utilisé une grille non-structurée qui offre un moyen efficace de caractériser la région d'Hawaii à l'aide d'une haute résolution et le restant de l'hémisphère Nord avec une résolution qui décroît au fur et à mesure que l'on s'éloigne d'Hawaii. La distribution de 46 composés gazeux avec 138 réactions, incluant une chimie détaillée des hydrocarbures non-méthaniques (isoprène, éthane, éthène, propène et alpha-pinène) est calculée avec un pas de temps de 20 minutes. A l'aide de notre modèle nous avons simulé une période de huit jours pour chacune des saisons. Les résultats des simulations ont été comparés aux observations et interprétés à l'aide d'études de rétro-trajectoires, de traceurs passifs et de bilans chimiques local et régional de l'ozone et de ses précurseurs.
Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished
Maréchal, Benoît. « Caractérisation et interprétation de la variabilité chimique et minéralogique des grès réservoirs.Implications pour la modélisation numérique de la diagenèse minérale des grès du Ravenscar Group (Yorkshire, Royaume-Uni) ». Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2000. http://tel.archives-ouvertes.fr/tel-00089197.
Ces descriptions sédimentologiques ne prennent pas en compte les caractères pétrographiques, minéralogiques ou géochimiques qui permettraient pourtant d'attribuer des causes directes, primaires ou secondaires, aux variations de porosité et de perméabilité rencontrées dans les roches. De plus, depuis quelques années, la diagenèse minérale, souvent à l'origine de ces variations, fait l'objet d'une modélisation déterministe qui s'appuie sur les processus physiques et chimiques mis en œuvre. Des logiciels de plus en plus performants permettent ainsi de réaliser des simulations destinées à proposer des bilans géochimiques variés qu'il est nécessaire de valider par des observations de terrain.
Cette thèse a pour objectif, d'une part, de compléter les études sédimentologiques par l'acquisition et l'analyse de données géochimiques et, d'autre part, de mieux comprendre la diagenèse des grès réservoirs en associant la géochimie à la modélisation numérique.
Deux formations géologiques, analogues de réservoirs exploités, ont servi de support à cette étude : les grès fluviodeltaïques du Ravenscar Group (Jurassique Moyen, côtes du Yorkshire, Royaume-Uni) et les Grès turbiditiques d'Annot (Eocène-Oligocène, Bassin du Sud-Est, France). L'échantillonnage a été réalisé afin d'apprécier la variabilité verticale et latérale de composition à diverses échelles (centimétrique à hectométrique) aussi bien entre faciès sédimentaires qu'au sein d'un même niveau lithostratigraphique.
L'étude géochimique montre que les faciès sont caractérisés par leur gamme de composition chimique ainsi que par leur style de variabilité élémentaire. Elle permet également de mieux comprendre la répartition des minéraux et des éléments au sein de la roche.
Ainsi, dans certains faciès, le tri sédimentaire entre les petits minéraux lourds et le reste de la roche (entrainment sorting) engendre des variations de teneur importantes pour les éléments portés par ces différentes classes de particules détritiques (Zr, Cr, Th, etc. pour les minéraux lourds ; Al, Na, K, etc. pour la fraction élastique). Des caractéristiques chimiques propres à chacune de ces populations de minéraux, valables à une échelle verticale de plusieurs mètres, peuvent alors être définies. Certaines d'entre elles, relatives aux éléments immobiles, permettent d'identifier des variations dans l'alimentation détritique. Une ségrégation s'opère également au sein de la fraction élastique entre les particules les plus grosses, dont la nature dépend de la maturité du grès, et les autres grains lors du dépôt.
Deux transformations diagénétiques majeures, à savoir la kaolinitisation et l'albitisation des feldspaths, sont également à l'origine de la distribution particulière des compositions chimiques de la fraction alumineuse des grès du Ravenscar Group.
Ce dernier point a été utilisé pour tester et valider la modélisation numérique de la diagenèse des grès du Ravenscar Group à l'aide du code numérique DIAPHORE de l'Institut Français du Pétrole. La néoformation de kaolinite apparaît alors possible dans la gamme de température 25-80°C, quel que soit le type d'eau superficielle considéré. La précipitation des argiles est induite par la présence et la circulation d'une eau en déséquilibre avec le réservoir gréseux, entraînant la dissolution successive des feldspaths. L'albitisation des feldspaths plagioclases s'effectue à faible température et dépend assez peu du type d'eau injectée. Enfin, l'albitisation des feldspaths potassiques est plus délicate à réaliser et n'est efficace que pour des eaux marines ou saumâtres à des températures supérieures à 50°C, et circulant dans un réservoir soumis à un gradient de température. Les simulations confirment donc l'importance de la perméabilité et de la circulation des fluides dans la diagenèse des aluminosilicates.
Les variations de composition chimique de la fraction alumineuse des grès du Ravenscar Group sont reproduites dans les simulations. Les conditions nécessaires aux transformations sont particulières mais compatibles avec le contexte géologique des grès étudiés. Les principales transformations diagénétiques, indépendantes, nécessitent alors plusieurs épisodes de circulation d'eau pour rendre compte de la diversité des compositions chimiques et minérales observées.
Les travaux menés dans le cadre de cette thèse laissent à penser que l'on pourrait intégrer plus systématiquement l'approche géochimique dans les études de réservoir.
Lu, Jun. « Développement de modèles prédictifs décrivant le couplage chimie-transport dans les sédiments naturels ». Thesis, Poitiers, 2013. http://www.theses.fr/2013POIT2287/document.
Management of soils or sediments contaminated by metals requires to predict the migration of metallic cations, whose mobility depends both on the transport properties of the medium and chemical reactivity of the system (principally sorption/desorption reactions). To study the sorption of metallic cations (major and trace) in dynamic condition, transport experiments using columns have been carried out with a soil poor in carbonated minerals and organic matter. Considering that the reactivity of this soil was mainly due to swelling clay minerals, a sorption model based on the sorption properties of the Wyoming montmorillonite and built according to a multi-site ion exchanger theory has been integrated into a 1D transport code. The predictions given by this model were then compared with the breakthrough curves measured in this study and those reported in the literature. The study of the reactive transport of major cations highlighted the significant role of protons (even at near neutral pH), and validated the model for major cations (Na and Ca). However, the study concerning Zn (II) showed a discrepancy between the results obtained from batch experiments and those issued from column experiments, which could be attributed to the contribution of another sorbent phase (illite). Finally, the proposed sorption model allowed reproducing with a good confidence experimental data reported from literature for sorption of Zn (II) in dynamic conditions
Sedqui, Abderrahim. « Modélisation et simulation numérique de l'interaction fluide-minéral. Application à l'échange chimique avec transport entre un fluide aqueux et une solution solide à trois pôles ». Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 1998. http://tel.archives-ouvertes.fr/tel-00841388.
Lu, Jun. « DEVELOPPEMENT DE MODELES PREDICTIFS DECRIVANT LE COUPLAGE CHIMIE-TRANSPORT DANS LES SEDIMENTS NATURELS ». Phd thesis, Université de Poitiers, 2013. http://tel.archives-ouvertes.fr/tel-00936585.
Meleux, Fréderik. « Modélisation de la pollution atmosphérique à différentes échelles : confrontations simulations/mesures pour la préparation d'Escompte 2001 ». Toulouse 3, 2002. http://www.theses.fr/2002TOU30196.
Denis-Vidal, Lilianne. « Identification d'un système biochimique, modélisation et contrôle d'un système de réacteurs ». Compiègne, 1993. http://www.theses.fr/1993COMPD640.
Guth, Jonathan. « Modélisation des aérosols à l'aide du modèle de chimie transport MOCAGE : application à la qualité de l'air dans le bassin méditerranéen ». Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30354/document.
The objective of this thesis are to establish a budget of the atmospheric aerosols on the Mediterranean basin and to characterize air quality over this region based on long term exposition indicators. Based on simulations made with the chemical transport model MOCAGE (Modèle de Chimie Atmosphérique à Grande Échelle), the first part of this work is devoted to the development of a secondary inorganic aerosols module. This module was validated at different scales using a large variety of types of data. The MOCAGE model has then been used to simulate the chemical composition on the Mediterranean basin over the year 2013. We were able to show that the Mediterranean area is an export zone for aerosols. We also studied the impact of marine and coastal anthropogenic emissions on the aerosol budget and the air quality in the basin
Bouissonnie, Arnaud. « Les cinétiques de dissolution : de l'approche mécaniste à l'échelle atomique à la description macroscopique à l'échelle centrimétrique ». Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAH013.
Dissolution kinetics represent a major challenge in the understanding of geological phenomena. During this thesis, several factors that could impact dissolution were studied in order to link different spatial scales. The dissolution of the model minerals of this thesis, enstatite and calcite, was studied from the atomic scale to the face scale for the first and from the face to the porous medium scale for the second. The dissolution anisotropy observed experimentally on enstatite could be reproduced using a probabilistic model. The interest of this type of model has been demonstrated and proposals for extending their use have been made. A surrogate model for the dissolution rate of enstatite linking the atomic scale to the face scale was also established. The study of calcite has demonstrated the importance of the selection of the rate law in dissolution rates upscaling studies. A column experiment and its simulation using a reactive-transport model demonstrated that the heterogeneity of the fluid flow around a mineral plays a major role in the dissolution of minerals
Aliat, Abdelaziz. « Modélisation d'un écoulement hypersonique de CO en déséquilibre physico-chimique et radiatif derrière une onde de choc ». Aix-Marseille 1, 2002. http://www.theses.fr/2002AIX11030.
Mallet, Vivien. « Estimation de l'incertitude et prévision d'ensemble avec un modèle de chimie transport - Application à la simulation numérique de la qualité de l'air ». Phd thesis, Ecole des Ponts ParisTech, 2005. http://pastel.archives-ouvertes.fr/pastel-00001654.
Boutahar, Jaouad. « Méthodes de réduction et de propagation d'incertitudes : application à un modèle de chimie-transport pour la modélisation et la simulation des impacts ». Phd thesis, Ecole des Ponts ParisTech, 2004. http://tel.archives-ouvertes.fr/tel-00007557.
La seconde est relative à la réduction du nombre de simulations demandé par la méthode Monte-Carlo classique de propagation d'incertitude. La technique utilisée ici est basée sur une représentation d'une sortie de modèle incertaine comme un développement de polynômes orthonormaux de variables d'entrées. Un autre point clé dans la modélisation intégrée d'impacts est de développer des stratégies de réduction des émissions en calculant des matrices de transfert sur plusieurs années de simulation. Une méthode efficace de calcul de ces matrices a été ainsi développée, notamment en définissant des scénarios "chimiquement" représentatifs.
L'ensemble de ces méthodes a été appliqué au modèle POLAIR3D, modèle de Chimie-Transport développé dans le cadre de cette thèse.
Gatel, Laura. « Construction et évaluation d'un modèle de transport de contaminants réactif couplé surface-subsurface à l'échelle du versant ». Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAU001/document.
Pesticide use on agricultural surfaces leads to a broad surface and subsurface water contamination in France. Awaiting a deep agricultural practices evolution and a sustained fall of the pesticide use, it is of interest to limit transfers form agricultural fields to rivers. In order to constrain those transfers, a deepen knowledge of processes at stake and their potential interactions is necessary, as well as taking full advantages of fields observations.The aim of this PhD is the reactive transfer processes integration in the Hydrological physically-based model CATHY (CATchment HYdrology) which simulates surface-subsurface coupled water flow and advectiv solute transport in three dimensions and in variably saturated situations. Linear adsorption and first order decay are implemented in subsurface. A mixing modules is added, and evens the concentration between surface runoff and subsurface first layer. This module simulates the solute mobilisation from soil to surface runoff. The water flow surface-subsurface coupling procedure is very accurate in CATHY, and the transport coupling procedure is improve in order to respect the mass conservation.The model is first evaluated on subsurface transfer laboratory experimentation data at a small scale (2 m long, o.5 m wide, 1 m deep). Results are compared to mass flux evolution in time and a Morris sensitivity analysis is conducted. The model is able to acceptably reproduce observation, and properly after a slight calibration. Horizontal and vertical saturated conductivities, porosity and the $n$ parameter of retention curve significantly influence hydrodynamics and solute transport. As a second step, the model is evaluated on data from a field wine hillslope on an intense rain event, therefore in a context with a lot of surface-subsurface interactions. A global sensitivity analysis is conducted and highlights same parameters as the Morris method. Interactions between parameters highly influence the variability of hydrodynamic and solute transfer outputs. Mass conservation is accurate despite the complexity of the context.The resulting model meets the objectives, its evaluation is strong even if its theoretically only valid in the precise context in which the evaluations where conducted. The model is robust and able to reproduce observed data. Some complementary processes are still missing in the model to properly represent transfer ways at the hillslope scale, such as subsurface preferential transfers and surface sedimentary transport
Grauffel, Cédric. « Etude in silico de la reconnaissance de la méthylation des lysines sur les queues d'histones ». Strasbourg, 2009. http://www.theses.fr/2009STRA6202.
Post-translationnal modifications (PTMs) of histone tails play an important role in cellular processes such as gene expression and regulation. They can act through their specific recognition by proteic domains belonging to chromatin remodeling factors (enzymes, transcription factors, etc). A particularly important modification is the methylation of specific histone tail sites, for which there exist many. Our goal was to get insights into the molecular selectivity of these proteic domains towards a given methylation site by taking advantage of the numerous structural data available in the Protein Data Bank. We studied the interactions between the domains and histone peptides, using molecular dynamics simulations combined with a protocol using the MM/PBSA method. A pre-requisite was to develop and validate force field parameters for the of PTMs. Our results notably revealed that some domains discriminate the methlyation sites by recognizing short linear sequence motifs. It thus appears that chromodomains are specific to an ARKmeS motif, while PHD fingers bind the ARTKme motif of H3. The study carried out on PHD fingers also proves that our overall results can be used as a reference for research of other effectors of histone tails
Quelo, Denis. « Simulation numérique et assimilation de données variationnelle pour la dipersion atmosphérique de polluants ». Marne-la-vallée, ENPC, 2004. http://www.theses.fr/2004ENPC0441.
This work has led to the development of a three-dimensional chemistry-transport model Polair3D which simulates photochemistry. Model-to-data comparison of ozone and nitrogen oxides measurements over Lille in 1998 has proven its reliability at regional scale. 4D-var data assimilation has been implemented. It relies on the adjoint model of Polair3D obtained through automatic diferentiation. An application of inverse modeling of emissions over Lille with real measurements has been performed. It has proven that the inversion of temporal parameters of nitrogen oxides emissions leads to a significant improvement of forecasts. The so-called second-order sensitivity allows to study the sensitivity of the inversion with respect to the data assimilation system itself by computing its conditioning. This is illustrated by two test cases: short-range dispersion of radionuclides and gas-phase atmospheric chemistry characterized by a wide range of timescales
Peiro, Hélène. « Assimilation des observations satellitaires de l'interféromètre atmosphérique de sondage infrarouge (IASI) dans un modèle de chimie-transport pour des réanalyses d'ozone à l'échelle globale ». Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30019/document.
Human activity produces gases impacting the climate and the air quality with important economic and social consequences. Tropospheric ozone (O3) is created by chemical reactions from primary pollutants as nitrogen oxides. O3 is the third most important greenhouse gas after carbon dioxide and methane. It is one of the most important pollutants due to its oxidant effects on biological tissue. Several sensors on board satellites measure ozone concentration in the Ultraviolet, visible, or in the Earth infrared radiance. The French national center for space studies CNES (Centre National d'Etudes Spatiales) has developed the infrared sounding IASI on board polar meteorological satellites METOP. IASI, in orbit for several years, has allowed to estimate concentration of atmospheric gases, particularly O3, with a spatio-temporal coverage never reached so far. Every day, IASI measures infrared spectrum of the atmosphere between 650 to 2700 nm with an horizontal resolution of 12 km, giving tens of Gigaoctet per day of geolocated data. These observations form a part of an ideal set of data for the Chemistry Transport Model (CTM). CTM are used to analyze and predict air quality and can take into account satellite data according to a mathematical procedure called 'data assimilation'. This technic allows to fill gaps in the satellite information (for instance due to clouds or during night for the UV-visible sensor) and to obtain 3D global fields of chemical species concentration on an hourly basis. Therefore, it is important to develop accurate and efficient algorithms to assimilate IASI data in the CTM's. To this end, the UMR/CECI (CERFACS) develops in collaboration with the CNRM/Météo-France an assimilation tool (named VALENTINA) to the CTM MOCAGE that has applications on global and regional scales for climate or air quality study. The CTM MOCAGE is part of the European Copernicus project on the atmospheric composition (CAMS). In addition, the UMR/CECI collaborates with the Laboratoire d'Aérologie that has developed for several years the SOFRID algorithm for the vertical profiles retrieval of IASI ozone data based on the radiative transfer code RTTOV. The study of this PhD includes the tridimensional production of tropospheric ozone analysis with data assimilation (MLS, IASI) in the CTM MOCAGE, and on the ozone variability. Hence, we demonstrate the analysis ability to reproduce tropospheric ozone in response to ENSO, by bringing new informations on the vertical structure of associated anomalies. The PhD also focuses on the study of biases between analyses and independent ozone soundings. One of the main reasons could be due to the use of the climatological a-priori and matrix error covariance associated, strongly biased (particularly around the tropopause) in the retrieval method of IASI ozone data. Therefore, the second part of the PhD has consisted implementation of a method that generates accurate a-priori to improve retrieved ozone profiles. As a conclusion, this PhD brings a significant progress towards the improvement of tropospheric ozone products from IASI instrument, that should contribute to the long-term monitoring of tropospheric ozone thanks to the operational nature of METOP satellites
Guillaume, Bruno. « Les aérosols : émissions, formation d'aérosols organiques secondaires, transport longue distance, zoom sur les aérosols carbonés en Europe ». Toulouse 3, 2006. http://www.theses.fr/2006TOU30260.
Guillaume, Bruno. « Les aérosols:émissions, formation d'aérosols organiques secondaires, transport longue distance- Zoom sur les aérosols carbonés en Europe - ». Phd thesis, Université Paul Sabatier - Toulouse III, 2006. http://tel.archives-ouvertes.fr/tel-00145318.
- une meilleure caractérisation des inventaires d'émissions de BC et OCp, en développant un nouvel inventaire des sources principales que sont les combustions de fuels fossiles et de biofuels (secteur industriel, secteur domestique, trafic). Cet inventaire, de résolution 25kmx25km, fournit les émissions de BC et OCp pour 1995, 2000, 2005, 2010 et comporte deux zooms régionaux : sur la France à la résolution 10kmx10km et sur la région de la campagne Escompte à la résolution 1kmx1km,
- le développement d'un nouvel outil de modélisation globale de BC et OC (primaire et secondaire) par couplage du module d'aérosol ORISAM (module sectionnel) (LA/INERIS/ADEME) avec le modèle global de chimie-transport TM4 (collaboration LA/KNMI), qui permet à la fois la prise en compte d'une distribution des aérosols suivant 8 classes de taille (0.04µm-10 µm) et la prise en compte d'une composition chimique détaillée des aérosols (BC et OCp constituant le noyau de la particule sur lequel condensent plus de 6 réactifs chimiques organiques/inorganiques),
- des simulations avec ce nouveau modèle global baptisé ORISAM-TM4, des confrontations de résultats avec les mesures de BC et OC et l'étude du transport longue distance des aérosols,
- des tests de sensibilité sur la formation des aérosols organiques secondaires (SOA) portant sur différentes familles de composés organiques volatils (COV) précurseurs de SOA et portant également sur l'hygroscopicité des SOA (caractère hydrophile/hydrophobe),
- enfin, j'ai couplé ce nouvel outil ORISAM-TM4 à un module radiatif pour déterminer les propriétés optiques des aérosols (épaisseur optique, albédo de simple diffusion) en mélange interne à l'échelle globale.
Vachon, Aurélia. « Etude du transport de l'oxygene dans des membranes lipidiques modeles, par marquage de spin en resonance paramagnetique electronique : apport a la radioprotection chimique :application a l'etude des ginkgolides ». Paris 6, 1988. http://www.theses.fr/1988PA066578.
Menegoz, Martin. « Modélisation globale des interactions atmosphère-aérosols ». Toulouse 3, 2009. http://thesesups.ups-tlse.fr/700/.
Aerosols influence the Earth radiative budget, both scattering and absorbing solar radiation and through their interactions with clouds. Before quantifying the impact of aerosols on climate, it is necessary to evaluate their concentration in the atmosphere. This is the topic of this work. In particular, three aerosols are studied : sulphate, black-carbon and desert dust. Multi-year simulations are analysed over Europe and high latitudes as a first step and at the global scale as a second step. They are compared with observations and with simulations performed by other models. Our model describe the atmospheric concentration of aerosols quite well. Mains sinks and sources are put forward for each aerosol, which allows to identify ways to better simulate their atmospheric distribution
Delage, Fabienne. « Etude de la fonction cinétique de dissolution d'un verre nucléaire ». Montpellier 2, 1992. http://www.theses.fr/1992MON20159.
Pascaud, Aude. « Déterminants des évolutions spatio-temporelles des retombées atmosphériques acidifiantes et eutrophisantes en France et élaboration d’un modèle de projection ». Electronic Thesis or Diss., Lille 1, 2013. http://www.theses.fr/2013LIL10105.
Atmospheric pollutants emitted by both natural and anthropogenic sources are precursors of secondary compounds such as acidic gases and aerosols, which can be transported over long distances. Atmospheric deposition is the ultimate sink for these pollutants and can lead to acidification and eutrophication issues. This research was conducted within the SESAME project as part of the PRIMEQUAL long distance pollution program. The objectives seek to identify determinants of atmospheric deposition changes and to evaluate policies of pollutant reductions. Statistical approaches were applied to measurement databases of three French networks: MERA, CATAENAT and BAPMoN. Several procedures were developed to consolidate and to compare the datasets for a descriptive analysis. Geographical and seasonal determinants were identified based on the chemistry of concentrations and deposition fluxes. The trends resulting from Sen Mann Kendall tests highlighted that the changes in chemical compositions of atmospheric deposition can be either linear or nonlinear with the identified determinants. The findings were used to develop a predictive model to forecast the deposition fluxes of sulfur and nitrogen species under different climate scenarios and over several decades. The exceedances of critical loads and their changes were evaluated from current and forecasted deposition fluxes. Finally, the density of measurement sites over the French area was strong enough to create maps of deposition fluxes, which were then compared to the EMEP model outputs
Chéron, Jonathan. « Study of the bacterial microenvironment in a bioleaching stirred tank bioreactor : transport phenomena and kinetic modelling in three-phase flow ». Electronic Thesis or Diss., Université de Lorraine, 2021. http://docnum.univ-lorraine.fr/public/DDOC_T_2021_0237_CHERON.pdf.
Extractive bioleaching is a range of technologies aiming at recovering metals contained in mineral resources using biological means. It was successfully implemented at the industrial scale and used either in the form of dump or heap treatments, or by using large-scale stirred tank reactors (STR). Recently, bioleaching is evolving towards the exploitation of unusual resources (very low-grades, complex mineralogy, or high sulphur content) caused by the declining trend in mean ore grades. Bioleaching STR have proven to be more efficient than the dump or heap treatments for the treatment of high-value resources (such as refractory gold ores) mainly thanks to the better control over the process. However, it still needs further technical optimization to reach economic viability in the case of unconventional resources. In this PhD work, a coupled bioleaching STR hydrokinetic model was developed to model and simulate the bacterial microenvironment / response to the local heterogeneities of the tank in order to establish optimization criteria. First, an experimental study was performed at laboratory-scale to obtain the data necessary for the calibration of the various models. This includes bioleaching tests in STR to gather kinetics parameters and abiotic studies to determine essential hydrodynamics parameters (Njs, kla). On a second study, a multi-scale solid-liquid CFD model was developed and simulated using various conditions of impeller geometries, solid concentrations, and agitation rates. The impact of these conditions on solid homogeneity and particle stress was assessed and basic sizing rules were extrapolated from the results. Lastly, a hydro-kinetic model of a multi-scale bioleaching STR was developed. For this, a CFD model describing the gas-liquid flow was developed and simplified using a compartment approach. This approach was modelled on MatLab and combined with previous results on kinetic and solid-liquid models. Finally, the compartment hydro-kinetic model was used to characterize the kinetics of bioleaching and was compared with experimental data
Wolff, Jean. « Un modèle théorique des mélanges ternaires de lipides et de cholestérol ». Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-01068363.
Tombette, Marilyne. « Modélisation des aérosols et de leurs propriétés optiques sur l'Europe et l'Ile de France : Validation, sensibilité et assimilation de données ». Phd thesis, Ecole des Ponts ParisTech, 2007. http://pastel.archives-ouvertes.fr/pastel-00004169.
Pascaud, Aude. « Déterminants des évolutions spatio-temporelles des retombées atmosphériques acidifiantes et eutrophisantes en France et élaboration d’un modèle de projection ». Thesis, Lille 1, 2013. http://www.theses.fr/2013LIL10105/document.
Atmospheric pollutants emitted by both natural and anthropogenic sources are precursors of secondary compounds such as acidic gases and aerosols, which can be transported over long distances. Atmospheric deposition is the ultimate sink for these pollutants and can lead to acidification and eutrophication issues. This research was conducted within the SESAME project as part of the PRIMEQUAL long distance pollution program. The objectives seek to identify determinants of atmospheric deposition changes and to evaluate policies of pollutant reductions. Statistical approaches were applied to measurement databases of three French networks: MERA, CATAENAT and BAPMoN. Several procedures were developed to consolidate and to compare the datasets for a descriptive analysis. Geographical and seasonal determinants were identified based on the chemistry of concentrations and deposition fluxes. The trends resulting from Sen Mann Kendall tests highlighted that the changes in chemical compositions of atmospheric deposition can be either linear or nonlinear with the identified determinants. The findings were used to develop a predictive model to forecast the deposition fluxes of sulfur and nitrogen species under different climate scenarios and over several decades. The exceedances of critical loads and their changes were evaluated from current and forecasted deposition fluxes. Finally, the density of measurement sites over the French area was strong enough to create maps of deposition fluxes, which were then compared to the EMEP model outputs
Cosme, Emmanuel. « Cycle du soufre des moyennes et hautes latitudes Sud dans un modèle de circulation générale atmosphérique ». Phd thesis, Université Joseph Fourier (Grenoble), 2002. http://tel.archives-ouvertes.fr/tel-00705168.
Dupont, Richard. « Emissions biogéniques de NO par les sols : Impact sur la chimie atmosphérique ». Toulouse 3, 2007. http://thesesups.ups-tlse.fr/255/.
Biogenic NO emissions are influenced by numerous ground parameters. We have observed influences diversity and variability impact on soil biological activity, responsible for these emissions. Because of this variability, the use of a powerful statistical tool, the neural network, turned out indispensable. In temperate and tropical conditions, it allowed to generate biogenic NO fluxes parameterisation equations according to relevant environmental parameters. Then, a tropical equation have been introduced into Meso-NH-C model to generate biogenic NO emissions and to represent their impact on atmospheric chemistry above western Africa. High modification of soil NO emissions distribution and intensity have been identified, as well as tropospheric NOx and O3 concentrations. These modifications were then validated from airborne measurement
Schiff, Manuel. « Effets de modifications diététiques sur le phénotype de la souris Harlequin, un modèle de maladie mitochondriale ». Paris 5, 2011. http://www.theses.fr/2011PA05T026.
Background: Therapeutic options in human mitochondrial oxidative phosphorylation (OXPHOS) diseases have been poorly evaluated mostly because of the scarcity of cohorts and the inter-individual variability of disease progression. Thus, while a high fat diet (HFD) is often recommended, data regarding efficacy are limited. Our objectives were 1) to determine our ability to evaluate therapeutic options in the Harlequin OXPHOS complex I (CI)-deficient mice, in the context of a mitochondrial disease with human hallmarks and 2) to assess the effects of a HFD. Methods and Findings: Before launching long and expensive animal studies, we showed that palmitate afforded long-term death-protection in 3 CI-mutant human fibroblasts cell lines. We next demonstrated that using the Harlequin mouse, it was possible to draw solid conclusions on the efficacy of a 5-month-HFD on neurodegenerative symptoms. Moreover, we could identify a group of highly responsive animals, echoing the high variability of the disease progression in Harlequin mice. Conclusions: These results suggest that a reduced number of patients with identical genetic disease should be sufficient to reach firm conclusions as far as the potential existence of responders and non responders is recognized. They also positively prefigure HFD-trials in OXPHOS-deficient patients
Mogoutov, Andrei. « Quelques modeles de transport et de reactions chimiques dans des milieux desordonnes ». Paris 6, 1993. http://www.theses.fr/1993PA066750.
Charlier, Florence. « Réactions autocatalytiques hétérogènes : vers le dimensionnement des réacteurs industriels de dissolution du dioxyde d’uranium ». Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0174/document.
Recycling of nuclear fuel is based on liquid – liquid extraction. The dissolution of uranium dioxide in nitric medium is hence a key step at the head - end of the entire process. This particular dissolution is triphasic and autocatalytic, which means that numerous phenomena must be taken into account. A complete understanding of these phenomena, at macroscopic and microscopic scale, is necessary in order to model the solid disappearance rate in dissolvers. The kinetical parameters of the reaction were determined for both the catalyzed and non-catalyzed reactions. The kinetic study was realized thanks to a single particle approach. The reaction rates were measured by optical microscopy. This analytical technic enables to limit the catalyst accumulation at the solid - liquid interface. Moreover, nitrous oxides are products of the uranium dioxide dissolution. Evidence of a volumic reaction between these gases and the catalyst were found, and the kinetics of this reaction was estimated from the experimental results. Gas – liquid exchanges were shown to have an important impact on the catalyst concentration in the reactor. A model was realized thanks to the software Matlab to simulate these different phenomena. It was shown to be in good agreement with experimental results, at the microscopic and macroscopic scale. Dimensionless numbers were highlighted to describe the impact of each phenomenon on the solid disappearance, including the influence of the geometry and hydrodynamics of the reactor. Finally, ways of process optimization for autocatalytic reactions were determined thanks to the model. For instance, gas – liquid and solid – liquid exchanges were shown to be an interesting lever to fix the catalyst concentration in the reactor and at the solid surface
Haeberlein, Florian. « Méthodes de décomposition de domaine espace temps pour le transport réactif --- Application au stockage géologique de CO2 ». Phd thesis, Université Paris-Nord - Paris XIII, 2011. http://tel.archives-ouvertes.fr/tel-00634507.
Chilkuri, Vijay Gopal. « Etude du phénomène de double échange : de l'origine microscopique aux propriétés collectives ». Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30152/document.
The materials like nickelates and manganites, show extraordinary magneto-electric properties originating from the double exchange (DE) phenomenon. In this work we try to understand the origin of these properties, not only at the microscopic level, by studying systems with two magnetic centers, but also at the macroscopic level, by studying collective effects in systems with varying sizes. The first part consists of an {it ab initio} study of a series of five conjugated organic systems, with two magnetic centers each, which are susceptible to exhibit DE phenomenon. The low lying eigenstates are used to extract the parameters of the DE Hamiltonian and substantiate the model. Thus, we show that there exist conjugated organic systems which could, in principle, possess magneto-electric properties similar to those observed in materials formed of transition metal oxides. The second part consists of a detailed study of the collective properties of the double exchange Hamiltonian in one dimensional systems of variable size. One dimensional chains made up of sites with two orbitals each and one or two electrons per site are studied with exact diagonalization methods. Novel tools have been developed to quantify the size of the ferromagnetic polaron and the amount of electron delocalization in the resulting ground state. Finally, we show how a magnetic field could bring about a drastic change in the electron delocalization in the system for a given doping ratio
Faure, Sandrine. « Étude de l'absorption du nitrate chez Brassica napus L. : évolution de l'activité des transporteurs et de la transcription des gènes NRT1 et NRT2 en réponse à une privation en NO 3, évaluation de leur rôle sur le cycle de culture ». Caen, 2000. http://www.theses.fr/2000CAEN2007.
Ducharme, Vincent. « Simulation de systèmes chimique et physiologique ». Mémoire, Université de Sherbrooke, 2013. http://hdl.handle.net/11143/6580.
Kha, Kim Quoc Nguyen. « Contribution à la modélisation et à la simulation numérique de la combustion turbulente pré-mélangée dans des régimes d'interaction chimie-turbulence extrêmes : Prise en compte des écarts à l'hypothèse de flamme mince ». Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2016. http://www.theses.fr/2016ESMA0018/document.
The present study is devoted to the modeling of turbulent reactive flows. In a first step of the analysis, one-dimensional flames are considered to scrutinize analytically and numerically the characteristics of the propagating flame front. Then, we introduce a new definition for the flamelet thickness that may differ from the laminar flame thickness. Accordingly a generalized and consistent form of the presumed probability density function(PDF) is proposed. The parameters of this PDF depend on the ratio of the Kolmo-gorov length scale to laminar flame thickness. The corresponding developments can be associated with a boundary layer description applied to the turbulent flame in which the thicknesses of the different sub-layers are determined from the sole knowledge of the turbulent Reynolds number Re and Karlovitz number Ka. This description leads to amodeling proposal (i) for the mean reaction rate as well as (ii) for the turbulent scalar flux. The values of all chemical characteristics are calculated from one-dimensional flame susing either the MathematicaTM software or detailed chemical kinetics computations.Numerical simulations are finally performed with the CFD code Code-Saturne and the model is validated through comparisons with reference experimental configurations :turbulent V-shaped flames and impinging flames. Satisfactory results are obtained for these two distinct configurations
Quélo, Denis. « Simulation numérique et assimilation de données variationnelle pour la dispersion atmosphérique de polluants ». Phd thesis, Ecole des Ponts ParisTech, 2004. http://pastel.archives-ouvertes.fr/pastel-00002101.