En raison de sa nature hautement inflammable, l’hydrogène constitue un risque technologique important et son utilisation nécessite un très haut niveau de sûreté. Le travail de thèse présenté dans ce mémoire a été réalisé en collaboration avec EDF et s’inscrit dans le cadre des études de sécurité liées à la libération d’hydrogène dans un des locaux de l’îlot nucléaire. Le dégagement d’une fuite peut, en effet, entraîner la formation d’une atmosphère inflammable, qui peut exploser et provoquer des graves dégâts.Cette étude vise ainsi à apporter une meilleure compréhension des phénomènes de dispersion et de déflagration à l’issue d’une fuite d’hydrogène. Les résultats expérimentaux obtenus à échelle de laboratoire sont comparés aux simulations numériques obtenues via le logiciel FLACS. Un plan détaillé a donc été élaboré, en divisant le mémoire en deux parties : dispersion et déflagration. Pour chaque partie, un point bibliographique est proposé, ainsi qu’une description des dispositifs expérimentaux utilisés. Une partie expérimentale et numérique est présentée pour chacun des deux phénomènes. Les travaux réalisés ici ont donc permis d’obtenir une analyse réelle et complète du phénomène de rejet d’hydrogène en milieu fermé et obstrué et d’explosion de mélange hétérogène hydrogène-air à petite et grande échelle. Les cas les plus pénalisants en termes de concentration maximale et gradient de concentration ont été identifiés à travers une étude paramétrique sur l’influence du débit et de la position du rejet sur la dispersion. Les conséquences lors de la déflagration de ces mélanges hydrogène-air ont ensuite été étudiées à travers l’analyse de l’onde de pression et de la propagation de la flamme. / The highly combustible nature of hydrogen poses a great hazard and its use imposes an accurate analysis of risk characterization and consequences to protect the installation and to reduce the potential risk. This thesis has been done in collaboration with EDF and it is included in the context of the explosion risks of an air hydrogen mixture in a room of the nuclear facility where there is a risk of accidental release. Indeed, the hydrogen can disperse quickly and burn easily in the presence of an ignition source causing heavy damage. The goal of this study is to provide a better understanding of the phenomena of dispersion and deflagration after an accidental release of hydrogen. Experimental results obtained at small scale are compared with numerical simulations obtained using FLACS code. A detailed plan has been drawn up, dividing the thesis into two parts: dispersal and deflagration. For each part, a bibliographic point is proposed, as well as a description of the experimental devices used. An experimental and numerical part is presented for each of the two phenomena. The studies carried out here have thus enabled us to obtain a real and complete analysis of the phenomenon of closed and clogged hydrogen discharge and small-scale and large-scale heterogeneous hydrogen-air mixture explosion. The most penalizing cases in terms of maximum concentration and concentration gradient were identified through a parametric study on the influence of the flow rate and the position of the rejection on the dispersion. The consequences during the explosion of these hydrogen-air mixtures were then studied through the analysis of the pressure wave and the propagation of the flame.

In this study, wet scrubbing and activated-carbon adsorption technologies were tested to investigate their abilities to remove total hydrocarbons (THCs) and other odorous compounds in the effluent gas from food-cooking operations such as frying, toasting, grilling, and steaming. A full-scale scrubber (gas-liquid contacting cross section 0.58 m¡Ñ0.50 m, height 0.80 m) was used in the present study for testing its performance on removing odorous compounds from a gas stream of 102 m3/min drawn from a Japanese-type grilling restaurant located in the Kaohsiung city. The scrubbing liquid had a flow rate of 67.2 L/min which is equivalent to a liquid/gas ratio of (L/G) 0.0065 m3 liquid/(m3 gas). Tap water, aqueous sodium hypochlorite solution, and aqueous hydrogen peroxide solution were used as scrubbing liquids. For the activated carbon tests, a 2-cm i.d. glass column packed with 20 g activated carbon which gives a packing height of 10.5 cm was used to obtain the adsorption isotherms by introducing a 15 L/min gas stream drawn from an oven toasting sausage. The gas flow resulted in a superficial gas velocity of 1.06 m/s over the cross section of the column. In addition, a pilot-scale adsorption unit (cross section 0.50 m sq., packed with 30 kg granular activated carbon) was installed for the adsorption test. A gas flow drawn from a vent of a restaurant kitchen cooking Chinese-type food was introduced into the pilot adsorber. A flow rate of 12.6 m3/min was used and the superficial gas velocity was 0.84 m/s. Results indicate that THC and odor (sensory test) removals of 15-35 and 35-65% were obtained, respectively, form the scrubbing test. There was no significant difference in the performance by using one of water or the two aqueous chemical solutions as the scrubbing liquor. Most of the characteristic food-grilling and flavoring smells were removed by the scrubber and some bitter smells like burnt carbon were found in the scrubbed gas. High moisture contents (around 95% in relative humidity) of the vent gas from the sausage-toasting oven resulted in a significant reduction in the activated carbon adsorption capacity for THCs from the tested gas. From results of the pilot-scale adsorption test, THC removals of 60-80% form the vent gas (around 50-60% in relative humidity) of the Chinese-type kitchen were found during the initial adsorption time of 0-50 hr. A long time (200 hr) operation resulted in a decrease in the THC removal efficiency. However, the adsorber exhibited as an odor equalization unit by reducing peaks of the odor emissions from the kitchen. Characteristic odors from various food cooking operations were reduced by the adsorber. It was estimated that a total of around NT$ 57 is required for the full-scale scrubber for treating the gas flow of 102 m3/min for an operation time of 7 hr per day, and the cost is equivalent to NT$ 1.33/(1,000 m3 gas). The cost for the activated carbon adsorption unit of 13 m3/min was estimated to be NT$ 134 for 8 hr per streaming day. The unit cost is NT$ 22.1/(1,000 m3 gas).

Un des objectifs a consisté à développer une étude systématique des caractéristiques d'allumage, depropagation et de combustion massique de combustibles liquides. La ré-inflammation des fumées riches estplus spécialement pris en compte. La recherche porte essentiellement sur les propriétés des feux dans uneenceinte avec ventilation contrôlée, sous ventilée. Les facteurs dominants à la ré-inflammation des fuméesriches est la quantité minimale d'hydrocarbures totaux et la température. Grâce à la Simulation Numériquedes Grandes Echelles, nous sommes allés à un niveau de détail permettant de prendre en compte l'influencede la ventilation sur la propagation de la flamme en milieu confiné. Les modèles numériques permet deprévoir les aspects aussi bien chimiques de la combustion (pyrolyse du combustible liquide, réaction dans laflamme), que thermodynamiques (transfert de chaleur et de masse flamme-liquide). L'enjeu est de concevoirun modèle de feu encore plus général, capable de traiter aussi les feux à grande échelle. Ce type de modèleest consacré à la mise en équations du problème et à la faisabilité d'une simulation numérique complexe.Les résultats obtenus sur les feux sur-ventilés sont en accord avec les résultats expérimentaux. Outre lesdifficultés théoriques de ce type de problème, il faut ajouter les difficultés pratiques liées à la durée trèsimportante des simulations sur ordinateur, et le coût de calcul élevé. / One of the objectives was to characterize systematically the ignition, the spread and the combustion of liquidf uel . Furthermore, the injlammation caused by rich smoke is especially taken into account. The researchfocuses on the properties of fire in an under-ventilated chamber with ventilation controlled The dominantfactors of rich smokes injlammation are the minimum amount of total hydrocarbons and the temperature.With the LES (Large Eddy Simulation) approach, the injluence of ventilation on jlame propagation inconfined areas is taken into account. Numerical models permit to predict the chemical aspects of combustion(liquid fuel 's pyrolysis, reaction in the jlame) and the thermodynamic (heat transfer and mass transferbetween the jlame and the liquid fuel). The challenge is to develop a model for more general fire which canalso handle large-scale fires. This type of model is devoted LO the setting of the equations of the problem andthe feasibility ofa complex numerical simulation. The results of the ventilated fires are in agreement with theexperimental results. ln addition 10 the theoretical difficulties of this type of problem, the practicaldifficull ies in the very long duration of computer simulations and the hig'" calculation 's cost must be added

A bass-reflex system is a type of loudspeaker design that uses a port or a vent to improve low-frequency performance. The port acts as a Helmholtz resonator which extends the bass response of the system. However, at high drive levels, the air inside the port can become turbulent and cause distortion, noise, and compression. From previous works, it is known that the geometry of the port plays a crucial role in reducing these unwanted effects. This paper serves to provide more insight into optimal port shape by performing several objective tests on a group of 5 different prototype port shapes based on findings from previous literature. Total Harmonic Distortion (THD) and port compression tests were conducted to determine which port presented the highest performance.

Winds create forces on buildings, sometimes with disastrous results. Low-slope roofs are subjected to potentially high levels of suction pressure, especially when winds strike the corner of a building, creating vortices. Traditional methods of attaching roof membranes to substrates are prone to failure when the low pressure on the roof surface instigates a transfer of forces to the roof membrane. Existing pressure-equalized roof systems use the power of the wind to transmit low pressure to the space immediately beneath the roof membrane, pulling the membrane down to the roof surface. The object of this study is the design of a wind vent which, when coupled with a single-ply roof membrane in a complete roof assembly, will successfully equalize low pressure throughout the entire field of the roof. The proposed wind vent differs from existing equalizer valves in its use of the Bernoulli effect to create low pressure. Optimized for ease of manufacturing and installation, the vent is omni-directional and contains no moving parts. After the wind vent prototype is developed, future study will be required to determine the tributary area of each vent, the interaction with the insulation beneath the membrane, the response time of the system when subjected to dynamic wind loading, the effect on the vent of various weather conditions, and the permissible amount of infiltration into the roof system. Associated research will also investigate the benefits of incorporating the heat evacuating capacity of the pressure-equalizing roof vent system into a roof membrane containing an amorphous photovoltaic array. / Master of Science

Conselho Nacional de Desenvolvimento Científico e Tecnológico / O comportamento territorial é uma estratégia de monopolização de recursos quando esses são essenciais para o sucesso reprodutivo de um organismo. Um território é uma área de uso exclusivo, defendido contra invasores coespecíficos de mesmo sexo, resultante da interação social entre vizinhos. A territorialidade exerce importante papel no sistema reprodutivo de uma espécie, pois influencia a participação do macho na reprodução. Nesses casos, as fêmeas podem obter vantagens diretas, como sítios de nidificação e cuidado parental. O comportamento territorial também exerce influência na regulação do tamanho populacional através de uma relação entre custos e benefícios individuais: em ambientes ótimos e com alta densidade populacional, os territórios são pequenos com pouca substituição, e jovens machos têm dificuldade para conseguirem estabelecer-se. O presente estudo teve como objetivo investigar aspectos comportamentais do tropeiro-da-serra, espécie rara e endêmica de Floresta Atlântica, com distribuição bastante restrita. Ao longo de 18 meses na Ilha Grande (RJ), analisamos seu comportamento territorial, mensuramos os tamanhos de territórios individuais de machos e realizamos estimativas de densidade populacional. O playback foi utilizado para atestar a presença de territorialidade na espécie, para simular a aproximação de coespecíficos (interações intraespecíficas) e para induzir o deslocamento dos indivíduos até os limites de seus territórios. Para investigar as respostas comportamentais à aproximação de invasores, analisamos quantitativamente as reações dos indivíduos a estímulos sonoros (vocalização espontânea e induzida pelo playback). Os territórios individuais foram definidos em duas estações reprodutivas através do método do Mínimo Polígono Convexo (MPC) em uma área equivalente a 20ha. A densidade populacional foi definida através do número de territórios encontrados e pelo número de indivíduos vistos/ouvidos por unidade de área através de transecções lineares. As vocalizações espontâneas e induzidas ocorreram somente entre os meses de agosto a janeiro, caracterizando uma estação reprodutiva bem definida. Durante este período, os machos tornaram-se solitários e agressivos com coespecíficos; na fase não-reprodutiva, entretanto, os indivíduos mostram-se sociáveis, forrageando em pequenos grupos de até quatro indivíduos. Os resultados indicam que o território é estabelecido para a monopolização de alimento e acesso às fêmeas. Essas observações sugerem que a espécie estudada é territorialista. Foram estimados sete territórios com valores entre 0,21ha e 0,73ha (0,43 + 0,16ha). Os indivíduos apresentaram fidelidade territorial, ocupando os mesmos territórios em duas estações reprodutivas. A densidade populacional de L. lanioides apresentou flutuações ao longo do ano, com os maiores valores encontrados durante a estação reprodutiva (variando entre 0,37 e 1,84 indivíduos/ha). Flutuações na densidade populacional podem apontar migrações altitudinais motivadas por variações na disponibilidade de recursos alimentares. Concluímos que o comportamento reprodutivo de L. lanioides não se enquadra no conceito de sistema reprodutivo em leks, conhecido em outros cotingídeos (ex. Lipaugus vociferans), no qual a corte é um comportamento social, com disputa por status de dominância, e o papel do macho resume-se à cópula sem benefícios diretos para as fêmeas. Dessa forma, os resultados do presente estudo trazem informações originais sobre a biologia de L. lanioides / Territorial behavior is a strategy to monopolize resources when these are important to reproductive success of an organism. A territory is an exclusive area, defended against intruders and same sex coespecific, coming from social interactions between neighbors. Territorial behavior performs an important role in a reproductive system species as well, because it influences male contribution on reproduction. In these cases, females can get direct benefits, as nesting sites and parental care. Territoriality also interferes in population size through a costs and benefits relation: on ideal environments and highly population density, territories are small and there are few substitutions because young males have difficulties to establish territories themselves. This present study researched behavioral aspects of Cinnamon-vented Piha, an endemic and rare Atlantic forest species, with restrict distribution. Throughout 18 months at Ilha Grande, RJ, we investigate its territorial behavior, measured males individual territories sizes and estimated population density. A playback was played to attest territoriality in species, simulate coespecific approaches (intraspecific interactions) and encourage individual displacements to their territories boundaries. To investigate behaviors responses to intruders invasions, we quantified males reactions to sonorous stimulus (spontaneous and induced vocalizations by playback). Their territories were defined during two reproductive periods by Minimum Convex Polygon (MCP) at an area equivalent to 20ha. Population density was defined by the number of territories found and the number of individuals seen/heard at an area unit by linear transections. On this period, males became solitary and aggressive with coespecific; in non-reproductive phase, however, they stood sociable, foraging in small groups up to four individuals. The results suggest that territories are established to monopolize food and access to females, therefore this studied species is territorialist. In total, seven territories were estimated with values between 0,21ha e 0,73ha (0,43 + 0,16ha). Individuals display territorial fidelity, preserving their territories along two reproductive seasons. L. lanioides population density ranged along the year showing highest values on reproductive season (0.37 and 1.84 individuals/ha). Fluctuations in population density can aim to altitudinal migrations motivated by variations of food resources availability. L. lanioides reproductive behavior does not fit in the reproductive leks system concept, attested in some other cotingas (eg. Lipaugus vociferans), in which courtship is a social behavior, with contests for dominance status, and male roles is restricted to copula without direct benefits for females. In this way, our results bring original information about L. lanioides biology

Conselho Nacional de Desenvolvimento Científico e Tecnológico / O comportamento territorial é uma estratégia de monopolização de recursos quando esses são essenciais para o sucesso reprodutivo de um organismo. Um território é uma área de uso exclusivo, defendido contra invasores coespecíficos de mesmo sexo, resultante da interação social entre vizinhos. A territorialidade exerce importante papel no sistema reprodutivo de uma espécie, pois influencia a participação do macho na reprodução. Nesses casos, as fêmeas podem obter vantagens diretas, como sítios de nidificação e cuidado parental. O comportamento territorial também exerce influência na regulação do tamanho populacional através de uma relação entre custos e benefícios individuais: em ambientes ótimos e com alta densidade populacional, os territórios são pequenos com pouca substituição, e jovens machos têm dificuldade para conseguirem estabelecer-se. O presente estudo teve como objetivo investigar aspectos comportamentais do tropeiro-da-serra, espécie rara e endêmica de Floresta Atlântica, com distribuição bastante restrita. Ao longo de 18 meses na Ilha Grande (RJ), analisamos seu comportamento territorial, mensuramos os tamanhos de territórios individuais de machos e realizamos estimativas de densidade populacional. O playback foi utilizado para atestar a presença de territorialidade na espécie, para simular a aproximação de coespecíficos (interações intraespecíficas) e para induzir o deslocamento dos indivíduos até os limites de seus territórios. Para investigar as respostas comportamentais à aproximação de invasores, analisamos quantitativamente as reações dos indivíduos a estímulos sonoros (vocalização espontânea e induzida pelo playback). Os territórios individuais foram definidos em duas estações reprodutivas através do método do Mínimo Polígono Convexo (MPC) em uma área equivalente a 20ha. A densidade populacional foi definida através do número de territórios encontrados e pelo número de indivíduos vistos/ouvidos por unidade de área através de transecções lineares. As vocalizações espontâneas e induzidas ocorreram somente entre os meses de agosto a janeiro, caracterizando uma estação reprodutiva bem definida. Durante este período, os machos tornaram-se solitários e agressivos com coespecíficos; na fase não-reprodutiva, entretanto, os indivíduos mostram-se sociáveis, forrageando em pequenos grupos de até quatro indivíduos. Os resultados indicam que o território é estabelecido para a monopolização de alimento e acesso às fêmeas. Essas observações sugerem que a espécie estudada é territorialista. Foram estimados sete territórios com valores entre 0,21ha e 0,73ha (0,43 + 0,16ha). Os indivíduos apresentaram fidelidade territorial, ocupando os mesmos territórios em duas estações reprodutivas. A densidade populacional de L. lanioides apresentou flutuações ao longo do ano, com os maiores valores encontrados durante a estação reprodutiva (variando entre 0,37 e 1,84 indivíduos/ha). Flutuações na densidade populacional podem apontar migrações altitudinais motivadas por variações na disponibilidade de recursos alimentares. Concluímos que o comportamento reprodutivo de L. lanioides não se enquadra no conceito de sistema reprodutivo em leks, conhecido em outros cotingídeos (ex. Lipaugus vociferans), no qual a corte é um comportamento social, com disputa por status de dominância, e o papel do macho resume-se à cópula sem benefícios diretos para as fêmeas. Dessa forma, os resultados do presente estudo trazem informações originais sobre a biologia de L. lanioides / Territorial behavior is a strategy to monopolize resources when these are important to reproductive success of an organism. A territory is an exclusive area, defended against intruders and same sex coespecific, coming from social interactions between neighbors. Territorial behavior performs an important role in a reproductive system species as well, because it influences male contribution on reproduction. In these cases, females can get direct benefits, as nesting sites and parental care. Territoriality also interferes in population size through a costs and benefits relation: on ideal environments and highly population density, territories are small and there are few substitutions because young males have difficulties to establish territories themselves. This present study researched behavioral aspects of Cinnamon-vented Piha, an endemic and rare Atlantic forest species, with restrict distribution. Throughout 18 months at Ilha Grande, RJ, we investigate its territorial behavior, measured males individual territories sizes and estimated population density. A playback was played to attest territoriality in species, simulate coespecific approaches (intraspecific interactions) and encourage individual displacements to their territories boundaries. To investigate behaviors responses to intruders invasions, we quantified males reactions to sonorous stimulus (spontaneous and induced vocalizations by playback). Their territories were defined during two reproductive periods by Minimum Convex Polygon (MCP) at an area equivalent to 20ha. Population density was defined by the number of territories found and the number of individuals seen/heard at an area unit by linear transections. On this period, males became solitary and aggressive with coespecific; in non-reproductive phase, however, they stood sociable, foraging in small groups up to four individuals. The results suggest that territories are established to monopolize food and access to females, therefore this studied species is territorialist. In total, seven territories were estimated with values between 0,21ha e 0,73ha (0,43 + 0,16ha). Individuals display territorial fidelity, preserving their territories along two reproductive seasons. L. lanioides population density ranged along the year showing highest values on reproductive season (0.37 and 1.84 individuals/ha). Fluctuations in population density can aim to altitudinal migrations motivated by variations of food resources availability. L. lanioides reproductive behavior does not fit in the reproductive leks system concept, attested in some other cotingas (eg. Lipaugus vociferans), in which courtship is a social behavior, with contests for dominance status, and male roles is restricted to copula without direct benefits for females. In this way, our results bring original information about L. lanioides biology