Дисертації з теми "Flatne"
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Erard, Valérie. "Etude spatiale et temporelle des champs thermiques et dynamiques de la combustion de prémélange turbulente instationnaire." Rouen, 1996. http://www.theses.fr/1996ROUES073.
Повний текст джерелаWalter, Géza. "Comparison of different flame types /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 2006. http://theses.uqac.ca.
Повний текст джерелаDelamare, Ludovic. "Modélisation numérique de la propagation d'une flamme turbulente en milieu confiné." Rouen, 1992. http://www.theses.fr/1992ROUES057.
Повний текст джерелаDuchaine, Patrick. "Experimental analysis of the dynamics of gaseous and two-phase counterflow flames submitted to upstream modulations." Phd thesis, Ecole Centrale Paris, 2010. http://tel.archives-ouvertes.fr/tel-00545418.
Повний текст джерелаProust, Christophe. "Contribution à l'étude des mécanismes de propagation des flammes dans les mélanges hétérogènes gaz-particules solides." Poitiers, 1988. http://www.theses.fr/1988POIT2268.
Повний текст джерелаDumont, Jean-Paul. "Etude de la structure spatiale de flammes turbulentes par laser." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37604738z.
Повний текст джерелаLamige, Sylvain. "Analyse de l'influence des conditions aux limites thermiques sur la stabilisation des flammes non-prémélangées." Thesis, Lyon, INSA, 2014. http://www.theses.fr/2014ISAL0099/document.
Повний текст джерелаNon-premixed flame stabilization is still an important issue in combustion. Addressing this issue requires to evaluate the relative importance of aerodynamic, thermal and chemical phenomena involved in the stabilization mechanisms. This thesis develops to this end an experimental approach, with a particular focus on the influence of thermal boundary conditions, examining the role of heat transfer in a twofold analysis. At first, the attachment zone of a rim-stabilized jet-flame is investigated, by careful consideration of the coupling existing between the burner lip temperature and the flame attachment location relative to the burner. Several regions have been identified according to the flame leading edge behavior, which evolves from diffusive to propagative closer to the aerodynamic stability limits. Besides, by modifying the burner thermal properties, a change has been shown in the relative roles of thermal and chemical quenching of the flame by the burner wall, depending on the burner lip temperature. Secondly, the attention is directed to transitions between different combustion regimes, namely attached and lifted flames. In particular, beyond the stable state of an attached flame, its lifting process is investigated. Examining in which conditions destabilization of the flame occurs indeed appears to be an ideal opportunity to gain insight into the aerothermochemical coupling and equilibriums existing prior to lift-off. Thus, the lifting process has been shown to be modified by the reactant initial temperature, in close relationship with the change in occurrence of localized transitory extinction events of the reaction zone
Matynia, Alexis. "Développement d'un dispositif expérimental pour l'analyse de la structure de flammes de prémélanges à haute pression par diagnostics laser : application aux flammes méthane/air et biogaz/air." Phd thesis, Université d'Orléans, 2011. http://tel.archives-ouvertes.fr/tel-00637824.
Повний текст джерелаLacas, François. "Modélisation et simulation numérique de la combustion turbulente dans les moteurs fusée cryotechniques." Châtenay-Malabry, Ecole centrale de Paris, 1989. http://www.theses.fr/1989ECAP0095.
Повний текст джерелаBouamoul, Amal. "Modélisation mathématique d'une flamme de diffusion méthane-air avec viciation et en configuration contre courant /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1999. http://theses.uqac.ca.
Повний текст джерелаCoudoro, Kodjo. "Etude expérimentale et modélisation de la propagation de flammes en milieu confiné et semi confiné." Thesis, Orléans, 2012. http://www.theses.fr/2012ORLE2005.
Повний текст джерелаThe context of the current study is the assessment of the occurrence of flame acceleration in accidental situations. The methodology developed for the assessment of hydrogen hazard in the nuclear industry led to the definition of a criterion for the prediction of the acceleration potential of a hydrogen/air/dilutant mixture based on its properties. This study aims to extend this methodology to gaseous mixtures that can be encountered in the classical industry. Therefore, three mixtures were chosen: the first two are representatives of a natural gas/air mixture: G27 (82%CH4/18%N2) and G222 (77%CH4/23%H2). The third one is a H2/CO (50%H2/50%CO) mixture and represents the Syngas. During this work, flammability limits were measured at 300 K and two initial pressures (1 and 2 bar) for each mixture. Fundamental flame speeds and Markstein lengths were also measured at three initial temperatures (300, 330, 360 K) and 2 initial pressures (1 and 2 bar) for each mixtures. A kinetic modeling was performed based on three detailed kinetic models and allowed the calculation of the global activation energy on the basis of the kinetic model which showed the best agreement with the experimental data. The acceleration potential for each mixture in presence of obstacles has then been investigated. It was found that different criteria were to be applied depending on whether the flame is stable or not. A predicting criterion was proposed in both case
Vignat, Guillaume. "Injection and combustion dynamics in swirled spray flames and azimuthal coupling in annular combustors." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASC024.
Повний текст джерелаThe deployment of low-emission technologies in aero-engines does not only require that new designs produce reduced amounts of pollutants, but also that their dynamical behavior (ignition, blow-off, and combustion instabilities) be compatible with the high safety standards prevailing in aeronautics. This research is focused on the latter aspect of combustor design. A transparent annular combustor equipped with 16 swirled spray injectors is used to represent at the laboratory scale the combustion chamber of a jet engine. This system is used in conjunction with a single sector rig to investigate dynamical issues.Theory, experimentation and large eddy simulation are combined to examine a range of items pertaining to the injector dynamics, flow structure, swirl number determination, spray characteristics, and coupling between injector flow and acoustic field. A database of injectors is introduced to investigate the impact of injection parameters on combustion dynamics. These injectors are examined under steady and unsteady conditions by combining laser diagnostics and high-fidelity simulations which allows the characterization of spray-specific behaviors of relevance to the dynamics of injection systems. One important result is that the presence of a liquid film formed on the wall of the injection unit gives rise to a multi-modal distribution of droplet velocities. A novel method is introduced to examine the space-time behavior of the flow and flame of a swirling injector submitted to axial modulations. A detailed investigation of the process by which convective perturbations couple with the acoustic field allows to examine the time lags that control combustion instability and sort out the respective roles of convection and droplet spray evaporation. High speed tomography relying on SnO2 particles provides major results on the Precessing Vortex Core structure and show its behavior under acoustic forcing. The impact of injector head loss on combustion instabilities is examined using several injection systems with similar levels of swirl. The head loss is shown to play a major role in the coupling between the flame and the upstream plenum. The previous results obtained in a single sector rig are used to guide experiments on the annular combustor. The focus is placed on high amplitude combustion oscillations coupled by a standing azimuthal mode inducing flame blow-off near the pressure nodal line. The deformation of the acoustic distribution is tracked using a novel expansion on azimuthal harmonics allowing the determination of the critical conditions leading to this phenomenon. New results are also presented about the transient dynamics of an injector during ignition and about lean blow out with a proof of concept extension of the LBO limit by nanosecond plasma discharges
Maugendre, Mathieu. "Etude des particules de suie dans les flammes de kérosène et de diester." Thesis, Rouen, INSA, 2009. http://www.theses.fr/2009ISAM0016/document.
Повний текст джерелаSoot are carbonaceous fine particles, which diameters are ranged from a few nanometres to a few micrometers. They have an impact on climate, due to their radiative properties, as well as on health, due to their small size. That’s why particulate matter is an important concern. In order to gain a better understanding of the influence of the combustion devices, which implies specific residence time and also specific turbulence, oxidation and pressure properties, we studied three specific kinds of combustion : first, laminar diffusion flames at atmospheric pressure ; then, a laminar diffusion flame a high pressures (3 to 5 bar) ; finally, a turbulent flame produced in a combustor at high pressures (1,2 to 3 bar). Another objective of this work was to improve the knowledge about soot produced by the combustion of liquid fuels, namely kerosene and biofuel. We studied morphological properties (fractal dimension, primary particle size…) and the refractive index m* of soot produced by these combustion systems. The technique employed to characterize the soot refractive index is based on the analysis of a part of smokes produced by flames. These are transported towards two optical cells, so that extinction and scattering coefficients can be measured, in addition to soot size distributions. Furthermore, a morphological characterization of the aggregates is conducted, using transmission electron microscopy (TEM) photographs. Rayleigh-Debye-Gans theory for fractal aggregates is used to determine two functions of the refractive index E(m) and F(m), so that m* can be deduced
Demesoukas, Sokratis. "Modélisation 0D/1D de la combustion pour l’optimisation des systèmes de combustion des moteurs à allumage commandé." Thesis, Orléans, 2015. http://www.theses.fr/2015ORLE2024.
Повний текст джерелаNowadays, the design of Spark Ignition internal combustion engines is focused on the reduction of fuel consumption and low pollutant emissions, while conserving an adequate output power. The high cost of experimental testing comes in favor of the use of numerical simulations for the assessment of engine technologies. Phenomenological Zero-Dimensional combustion models allow evaluating various technical concepts since they take into account various aspects of spark ignition combustion such as chamber geometry, laminar flame characteristics (thickness and speed) and the impact of turbulence. Such models also calculate species concentration of the exhaust gases. In order to create a zero-dimensional combustion model, which can be able to describe correctly the physics of combustion, the key aspects of laminar and turbulent premixed combustion are identified. Three versions of typical combustion models are compared in terms of physical description of the combustion process. The result of this comparison indicated the most physically pertinent mod-el (the Flame Surface Density model). This model is retained and is enhanced with physical modeling of the several phenomena, which affect the heat release rate. Those phenomena are the wall-flame interaction, post-flame reactions and flame stretch. Finally, the proposed model is validated for several engine configurations. Each configuration has an impact on a specific engine parameter. This analysis shows which are the confidence intervals and the limitations of the proposed model
Palies, Paul. "Dynamique et instabilités de combustion des flammes swirlées." Phd thesis, Ecole Centrale Paris, 2010. http://tel.archives-ouvertes.fr/tel-00545421.
Повний текст джерелаGueniche, Hadj Ali. "Compréhension de la formation des suies : étude de la combustion de précurseurs des cycles aromatiques en flamme laminaire prémélangée." Thesis, Vandoeuvre-les-Nancy, INPL, 2007. http://www.theses.fr/2007INPL027N/document.
Повний текст джерелаSoots and polyaromatic hydrocarbons (PAH), which are present in the exhaust gas of diesel engines, represent a large part of the urban pollution. Many efforts have then been focused on reducing the emissions of these compounds. The formation of soot precursors and PAH in combustion involves small unsaturadted hydrocarbons the chemistry of which is still very uncertain. Allene, propyne, 1,3-butadiene and cyclopentene are intermediate products in the combustion in cars engines. This work has led to a better understanding of several important paths in the formation of benzene and toluene. The chapter I of this report presents a bibliographic review of former work on the oxidation of methane, allene, propyne, 1,3-butadiene and cyclopentene. Chapter II gives a detailed description of the experimental set up used during this work to study the structure of the premixed flat laminar flames. Chapters III, IV and V present our experimental results obtained in laminar premixed flat flames and also the comparison with simulations
Bariki, Chaimae. "Interaction entre une flamme de prémélange et une structure tourbillonnaire." Thesis, Orléans, 2018. http://www.theses.fr/2018ORLE2067.
Повний текст джерелаUnderstanding and predicting the different mechanisms at play in turbulent premixed flames is a tremendously difficult issue for sizing or optimizing many combustion systems. Turbulent reactive flows are characterized by a complex interaction between the fluid motion, the inherent heat generated by the flame and turbulence. This challenge being extremely difficult to meet, the study of the interactions between a flat flame and a toroidal vortex provide an ideal canonical framework to better understand the physical mechanisms at play. In this perspective, experimental studies were carried out using a stagnation burner fed by a premixed fuel and air (methane/air,propane/air, hydrogen/air). A panel of experimental techniques as well as numerical tools have been used to characterize thoroughly the flame/vortex interactions. By modifying the equivalence ratio, the mixture composition and the vortex intensity, the temporal evolution of the interaction enable the extraction of the flame surface, the flame front stretch and curvature as well as the displacement/consumption speeds. In addition, the internal flame structure is deeply investigated by decomposing the flame front into a preheat zone and a reaction zone
Boukhalfa, Abdelkrim. "Combustion a l'etude de la structure scalaire dans les flammes turbulentes premelangees du type bunsen." Orléans, 1988. http://www.theses.fr/1988ORLE2043.
Повний текст джерелаRocchi, Jean-Philippe. "Simulations aux grandes échelles de la phase d'allumage dans un moteur fusée cryotechnique." Phd thesis, Toulouse, INPT, 2014. http://oatao.univ-toulouse.fr/14667/1/rocchi.pdf.
Повний текст джерелаBougrine, Sabre. "Modélisation 0D de la combustion des carburants alternatifs dans les moteurs à allumage commandé." Phd thesis, Ecole Centrale Paris, 2012. http://tel.archives-ouvertes.fr/tel-00740654.
Повний текст джерелаHalloum, Wafaa. "Développement d’une stratégie analytique dédiée aux esters organophosphorés. Contribution à l’évaluation de l’exposition alimentaire de l’homme à ces contaminants ré-émergents via l’alimentation." Thesis, Nantes, Ecole nationale vétérinaire, 2017. http://www.theses.fr/2017ONIR092F/document.
Повний текст джерелаAs recent studies highlighted that several organophosphate esters (OPEs) exhibit potential endocrine disrupting effects, in-depth risk assessment is required, when their global use as flame retardants and plasticizers is considerably increased. Despite previous efforts on the analysis and exposure assessment of these re-emerging contaminants in various abiotic environmental compartments, still limited information is available in biota samples, partly due to the lack of efficient analytical strategies. The thesis aimed first at developing a robust analytical strategy dedicated to the determination of a wide range of OPEs at trace levels in fish and other foodstuffs. The developed strategy involved selective pressurized liquid extraction with Florisil® as lipid sorbent, followed by further purification step by gel permeation chromatography. The extract analysis was then performed by gas chromatography coupled to tandem mass spectrometry fitted with electron impact or atmospheric pressure chemical ionisation mode, the latter being a more specific and innovative approach. The second aim was to apply the developed strategy to produce original occurrence data that can be useful for exposure assessment at the French level. Fish sample sets exhibited levels below 10 ng/g fw while packaged foodstuffs presented levels up to 100 ng/g fw. A first interpretation of these data in terms of dietary human quantitative risk assessment through fish consumption tended to show low risk ratios in connection with available toxicological data. However, additional exposure and toxicological data is required before any conclusions regarding public health implication can be drawn
Xia, Meng. "Etudes expérimentales et numériques de la pyrolyse et l’oxydation du charbon pulvérisé dans les flammes étirées de méthane/oxygène/azote." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLC060/document.
Повний текст джерелаIn the present work, a laboratory-scale laminar strained configuration is used to investigate the characteristics of pulverized coal devolatilization and oxidation in a mixture of CH4/O2/N2 reactive flow both in conventional air conditions and in oxygen-enriched combustion conditions. Two optical diagnostics, Flame Emission Spectroscopy and measurement of spontaneous emission, are employed for the characterization of flame structure. The spatial concentration evolution of three excited radicals, OH*, CH*and C*2 , are measured and analyzed.1-D simulations using detailed gas-phase kinetics including OH*, CH*, and C*2 sub-mechanisms and coal combustion submodels are performed and compared with experimental data. Qualitative comparison with experiments showed that the current numerical configuration was suitable for the prediction of OH*, CH* and C*2 emission. The predicted results differed with changes to the coal sub-models and kinetic parameters. The devolatilization model and volatile matters seem to play more important roles
Dounia, Omar. "Numerical investigation of gas explosion phenomena in confined and obstructed channels." Phd thesis, Toulouse, INPT, 2018. http://oatao.univ-toulouse.fr/20584/1/DOUNIA_Omar.pdf.
Повний текст джерелаTalbaut, Martine. "Etude de la formation et de l'oxydation des suies dans des flammes de diffusion laminaires d'éthylène : approches expérimentale et numérique." Rouen, 1996. http://www.theses.fr/1996ROUES015.
Повний текст джерелаJoyeux, Daniel. "Etudes expérimentales et numériques de la production des suies dans des flammes de diffusion turbulentes." Rouen, 1993. http://www.theses.fr/1993ROUES049.
Повний текст джерелаFlack, Elizabeth F. "The differential characteristics between transformational change experiences and volitional change in recovering substance dependent individuals." View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-1/flacke/elizabethflack.pdf.
Повний текст джерелаCarcillo, Magalie. "Etude des phénomènes liés à la propagation de flamme sur câble : instrumentation, formulation et modélisation." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS132.
Повний текст джерелаAssociated with a significant fire risk, electrical cables are subject to strict regulations in regard to their fire reaction. Standards were established to encourage cable manufacturers to produce fire-resistant cables with low toxic fumes. The electrical cables have to be classified according to the Euroclasses according to their performance in two standard fire tests: IEC 60332-1 (single cable test) and EN 50399 (large scale test on a cable ladder). The aims of the thesis were to analyze the main characteristic parameters of the cables governing their classification in the large scale test and to develop methods to predict this classification without having to carry out the test. Correlations were highlighted between the EN 50399 test and the characteristics of the cables but also between the EN 50399 test and small scale tests (IEC 60332-1 test and calorimeter cone). More than the correlations made between the fire tests, the influences of material parameters such as sheath thickness, the amount of isolation or the structure of the cables, were studied for the fire reaction of the cables during these three tests. As expected, the sheath plays a major role in protecting the internal fuels during the first moments of combustion. However, the non-flame retarded insulation eventually degrades, fueling the flame and intensifying the heat release rate. An analytical model was optimized during the thesis to predict the curve of the heat release rate for cables burning under the calorimeter cône, using the cable structure, test configuration and irradiance parameters. In addition, a numerical simulation of cone calorimeter tests has been proposed using finite element modeling. Complex geometry had to be implemented in order to properly predict the HRR curve of the cone. An analytical method wasn developed to predict the fire classification of electric cables from cone calorimeter results
Neveu, Fabrice. "Mesures simultanées de la température et de la vitesse dans une flamme turbulente non prémélangée méthane-air, stabilisée par un bruleur de type Bluff-Body." Rouen, 1994. http://www.theses.fr/1994ROUES079.
Повний текст джерелаVakiener, Adam R. "Preliminary investigation of flange local buckling in pultruded wide flange structural shapes." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/19562.
Повний текст джерелаDomingues, Eric. "Mesure des concentrations de OH dans des flammes haute pression par fluorescence induite par laser (TOPLIF) et par mélange dégénéré à quatre ondes." Rouen, 1993. http://www.theses.fr/1993ROUES057.
Повний текст джерелаGuo, Huimin. "Flame and acoustic waves interactions and flame control." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/flame-and-acoustic-waves-interactions-and-flame-control(d6306221-905e-425f-9144-d40453eabb7f).html.
Повний текст джерелаNicolau, Florentina. "Géométrie et platitude des systèmes de contrôle de poids différentiel minimal." Thesis, Rouen, INSA, 2014. http://www.theses.fr/2014ISAM0014/document.
Повний текст джерелаFirstly, we study flatness of multi-input control-affine systems. We give a complete geometric characterization of systems that become static feedback linearizable after a one-fold prolongation of a suitably chosen control. They form a particular class of flat systems, that is of differential weight equal to n+m+l, where n is the dimension of the state-space and m is the number of controls. We illustrate our results by several examples. Secondly, we give a complete geometric characterization of systems locally static feedback equivalent to a triangular form compatible with the m-chained form. We analyze and solve their flatness. We discuss singularities and provide a system of first order PDE's to be solved in order to find all x-flat outputs. We illustrate our results by an application to a mechanical system: the coin rolling without slipping on a moving table
Brossard, Christophe. "Contribution à l'étude de l'inhibition de la post-combustion : caractérisation aérothermochimique d'une flamme plane basse pression ensemencée en potassium." Rouen, 1995. http://www.theses.fr/1995ROUES054.
Повний текст джерелаBelhi, Memdouh. "Simulation numérique de l’effet de champ électrique sur la stabilité des flammes de diffusion." Thesis, Rouen, INSA, 2012. http://www.theses.fr/2012ISAM0007/document.
Повний текст джерелаThe application of electric field is known to have the ability to improve significantly the flame stability. In this regard, a mathematical approach to model combustion in the presence of an electric field was developed. The Navier-Stokes equations along with transport equations for charged species and the electric potential Poisson’s equation are solved. A main situation, that concerns the stabilization of diffusion flames by applying a direct or alternating electric field, is studied. The results show that the presence of the electric field improves the flame stabilization. The magnitude of this improvement depends on the intensity and polarity of the applied voltage. If the applied voltage is alternating, an additional factor, which is the frequency of the electric current, influences also the extent of the flame stabilization improvement. An interpretation of the stabilization mechanisms is proposed
Lhuissier, Gavrovic Natalija. "Caractérisation de suies dans les flammes de prémélange par diffusion quasiélastique de la lumière." Rouen, 1987. http://www.theses.fr/1987ROUES020.
Повний текст джерелаHallsteinsen, Lars Møllersen. "Romladningsdistribusjon i PEX HVDC kabelisolasjon - flate prøver og miniatyrkabel." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elkraftteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19030.
Повний текст джерелаPonty, Ludovic. "Application de la diffusion Rayleigh induite par laser à la caractérisation des fronts de flamme laminaire de prémélange H2/CH4/Air et H2/CO/Air." Phd thesis, Université d'Orléans, 2011. http://tel.archives-ouvertes.fr/tel-00647320.
Повний текст джерелаAguerre, Frédéric. "Etude expérimentale et numérique des flammes laminaires étirées stationnaires et instationnaires." Châtenay-Malabry, Ecole centrale de Paris, 1994. http://www.theses.fr/1994ECAP0385.
Повний текст джерелаVarea, Emilien. "Experimental analysis of laminar spherically expanding flames." Phd thesis, INSA de Rouen, 2013. http://tel.archives-ouvertes.fr/tel-00800616.
Повний текст джерелаMenard, Raphaël. "Synthèse de retardateurs de flamme phosphorés biosourcés pour résines époxy Synthesis of biobased phosphate flame retardants Synthesis of biobased phosphorus-containing flame retardants for epoxy thermosets Comparison of additive and reactive approaches From bio-based phosphorus-containing epoxy monomer to fully bio-based flame-retarded thermosets Synthesis of new flame-retardants by radical chain transfer copolymerization of glycidyl methacrylate and dimethoxy-phosphorylmethyl methacrylate." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2015. http://www.theses.fr/2015ENCM0013.
Повний текст джерелаThe toxicity and the bioaccumumulative character of the usual halogenated flame retardants(RFX) lead to uses restrictions of the main FRX (PBDE) in the EU as REACH. The phosphorus-containing flame retardants (FRP) are suitable for the epoxy thermoset because of their action on the hydroxyl groups. Moreover, the FRP are less toxic than the FRX. With the rise of the biobased epoxy thermosets, the dependence on fossil fuels for the additives synthesis has become problematic. Thus, these works are designed in a sustainable development approach through the valorization of a biobased compound which is representative of the biobased phenolic structures. The directe functionalization of the phloroglucinol with phosphate functions has achieved a first generation of biobased additives FRP which exhibit a significant action in the condensed phase and reduce the heat released during the thermal degradation of the fire retarded thermosets. This effect results in a strong intumescence at macroscopic scale and the expanded residue acts as a barrier and leads to a partial degradation of the thermoset. However, these additives plasticize the thermoset network and reduce the glass and the mechanical transition temperatures. A two-steps functionalization of the phloroglucinol leads to two new biobased FRP, an additive (P3SP) and a reactive (P2EP1SP), with similar chemical structures. We were able to highlight the benefit of the reactive approach which favors the condensed phase action and the intumescence. Moreover, the reactive approach ensures the durability of the flame retarded thermoset properties. Since the reactive approach seems more efficient than the additive one, an other reactive FRP was synthesized, whose the structure was optimized to reduce the plasticizing effect of the phosphorus-containing group. Finally, the study of different 100% biobased phosphorus-containing thermosets highlighted that the disadvantages of the reactive approach may be balanced by the incorporation of a high functionality epoxy precursor or an aromatic curing agent
Roche, Bruno. "Prédiction numérique des écoulements turbulents réactifs : Flamme turbulente oblique prémélangée et interaction flamme/tourbillons." Ecully, Ecole centrale de Lyon, 1995. http://www.theses.fr/1995ECDL0028.
Повний текст джерелаThe analysis and modelisation of the turbulent combustion is an important step for the study and simulation of industrial devices such as reciprocating engines of burners. The problem complexity is linked to the interaction between the thermo-chemical phenomena of the flame front and the scales of the turbulence spectrum. This problem can be simplified if we discretize the turbulence spectrum by treating each turbulent scale as a vortex. Our work in this domain follows two main axis : the prediction of a turbulent flame front and the simulation between an oblique flame front and a von Karman vortex street. The first part starts with the simulation of a laminar reference case. Then, the turbulent premixed oblique flame front is studied. The problem of the Lewis number influence on the flame structure is treated using two cases of mixing, hydrogen-air and methane-air. In a second part, we study the interaction between laminar premixed hydrogen-air oblique flame front and a von Karman vortex street. The prediction of this phenomenon show the vortex influence on the wrinkling and the extinction of the flame front. For each step, the comparison between numerical predictions and experimental data is realized. It allows us to analyze the performance of the modelisations and gives complementary data on the studied phenomena
Sufran, Mansor. "COMPARISON OF STRENGTH, DUCTILITY AND STIFFNESS OF FREE FLANGE AND WELDED FLANGE PLATE CONNECTION." OpenSIUC, 2019. https://opensiuc.lib.siu.edu/theses/2632.
Повний текст джерелаHadef, Redjein. "Mesure du nombre de markstein pour une flamme de premelange plissee." Aix-Marseille 1, 1987. http://www.theses.fr/1987AIX11127.
Повний текст джерелаMével, Rémy. "Etude de mécanismes cinétiques et des propriétés explosives des systèmes hydrogène-protoxyde d'azote et silane-protoxyde d'azote : application à la sécurité industrielle." Phd thesis, Université d'Orléans, 2009. http://tel.archives-ouvertes.fr/tel-00517364.
Повний текст джерелаObounou, Marcel. "Modélisation de la combustion turbulente non prémélangée avec prise en compte d'une cinétique chimique complexe." Rouen, 1994. http://www.theses.fr/1994ROUE5011.
Повний текст джерелаMantel, Thierry. "Contribution à la modélisation de la combustion dans les moteurs à allumage commandé avec prise en compte de la phase d'allumage." Rouen, 1993. http://www.theses.fr/1993ROUES010.
Повний текст джерелаLecordier, Bertrand. "Etude de l'interaction de la propagation d'une flamme prémélangée avec le champ aérodynamique, par association de la tomographie laser et de la vélocimétrie par images de particules." Rouen, 1997. http://www.theses.fr/1997ROUES060.
Повний текст джерелаGlibo, Adnan. "Flatness calculation of metal stream." Thesis, Linköpings universitet, Institutionen för teknik och naturvetenskap, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-96189.
Повний текст джерелаVid ståltillverkning har ytornas planhet stort kommersiellt intresse. I examensarbetet beskrivs en mätapparat för mätning av stål ytans planhet vid AB Sandvik Materials Technology i Sandviken. Examensarbetet omfattar genomgång av gammal programkod/dokumentation och framtagning av en algoritm för beräkning av planhet. Det äldre programmet ”PLANHETSMÄTNING 839:2” är skrivet i DOS. Algoritmen har nu implementerats i LabVIEW för ett nytt mätsystem och jag har jämfört hur det nya mätsystemet mäter planhet relativt det äldre DOS baserande mätsystemet. I detta examensarbete har jag undersökt hur definitionen för planhet ser ut i ett befintligt planhetsberäkningsprogram. Planhet beräknas som avståndet mellan max- och minvärde på en planhets kurva. För att kunna få ut max- och minvärde behöver man beräkna, utvärdera och justera insamlade data. Detta görs med programmet ”PLANHETSMÄTNING 839:2”. De begränsningar som finns i DOS-programmet är antal sampel och maximal bredd på bandet. Maximalt antal sampel är 2 600 och maximal bredd på bandet är 260 mm. I det nya mätsystemet sker mätningen med en induktivgivare som ger en god linjäritet, har hög upplösning och precision. Den analoga utgången från givaren A/D-omvandlas av ett insamlingskort. Insamlade data justeras, utvärderas, beräknas och plottas med ett LabVIEW program. I det nya programmet ”PLANHETSMÄTNING 839” används färdiga funktioner och dessa funktioner är omvandling från volt till mm, bestämning av max- och minvärdet på kurvan och bearbetning av insamlad data så som filtrering mm. I dessa färdiga funktioner görs inställningarna beroende på hur man vill att funktionen ska arbeta. De begränsningar som finns i examensarbete är att det inte görs någon filhantering av de sparade mätfiler och att induktivgivaren endast klarar av noggrann mätning av planhet i intervallet 0-1 mm. Rörelsesträckan som givaren gör under mätningen är begränsad till 350 mm vilket innebär att maxbredden på bandbiten inte kan överstiga 350 mm. Prestandan jämfördes genom att mäta en kalibrerad bandbit med både det äldre och det nya mätsystemet och där planheten jämfördes. Ca 40 mätningar gjordes på den kalibrerade bandbiten och planheten beräknades. Planheten med det äldre programmet beräknades till 0,07± 0,01 mm medan planheten i det nya programmet beräknades till 0,06 + 0,01 och 0,06 – 0,00 mm.
Rochette, Bastien. "Modeling and simulation of two-phase flow turbulent combustion in aeronautical engines." Thesis, Toulouse, INPT, 2019. http://www.theses.fr/2019INPT0059.
Повний текст джерелаNowadays, more than 80% of the energy consumed on Earth is produced by burning fossil fuels. Alternative solutions to combustion are being developed but the specific constraints related to air transport do not make it possible to currently power engines without introducing a technological breakthrough. These findings explain the research activity to improve the knowledge and the control of combustion processes to design cleaner, and more efficient aeronautical engines. In this framework, Large Eddy Simulations (LES) have become a powerful tool to better understand combustion processes and pollutant emissions. This PhD thesis is part of this context and focuses on the models and numerical strategies to simulate with more accuracy turbulent gaseous and two-phase reacting flows in the combustion chamber of aeronautical engines. First, a generic and self-adapting method for flame front detection and thickening has been developed for the TFLES model, and validated on several academic configurations of increasing complexity. This generic approach is then evaluated in the LES of a laboratory-scale burner and compared to the classical thickening method. Results show a more accurate thickening in post-flame regions. Second, from the analysis of 1-D homogeneous laminar spray flames where the dispersed phase has a relative velocity compared to the carrier phase, two analytical formulations for the spray flame propagation speed have been proposed and validated. The agreement between the overall trend of both the measured/estimated spray flame speeds demonstrates that the model and its parameters correctly take into account the main physical mechanisms controlling laminar spray flames. Finally, the state-of-the-art TFLES models were tested on complex turbulent gaseous and two-phase reacting configurations. The pros and cons of these models were investigated to contribute to the understanding of the mechanisms related to turbulent combustion, and to propose a LES modeling strategy to improve the fidelity of reactive simulations
Jaafar, Nisrine. "The blue flame and the red flame : love and eroticism." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ64032.pdf.
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