This research examines the drying of hardwood timber with particular reference to seasoning blackbutt (Eucalyptus pilularis) in a solar kiln. The aims of this research were to develop an optimised drying schedule for drying blackbutt and to develop and validate a mathematical model for a solar kiln. In the first stage of this study, the cross-grain physical and mechanical properties were determined for blackbutt timber so that an optimised schedule (based on drying within a limiting strain envelope) can be developed using model predictive control techniques for drying 43 mm thick (green) blackbutt timber boards in solar kilns. This optimised schedule has been developed and tested in the laboratory. The drying time was 10% shorter for this schedule than the original schedule, compared with an expected reduction in drying time of 14% (relative to the original schedule). Overall the quality was slightly better and the drying time was shorter for the optimised schedule compared with the original schedule. A complete solar kiln model has been developed and validated based on comparisons between the predicted and the measured internal air temperatures, relative humidities and timber moisture contents. The maximum difference between the actual and predicted moisture contents was 0.05 kg/kg. The agreement between the predicted and measured temperatures of the internal air is reasonable, and both the predictions and measurements have a similar cyclical pattern. The generally good agreement between the model prediction of the final moisture content and its measurement may be due to the careful measurement of the boundary conditions such as the solar energy input. The key uncertainties were identified as the heat exchanger output, the measurement of the initial moisture content, the amount of accumulation of condensate on the floor, and the estimation of sky temperature. The significant uncertainty (18%) in the estimation of the initial moisture content is a key reason for the mismatch between the model prediction and the measurements. In terms of operating variables, the energy release rate from the heat exchanger had the greatest effect on the simulated performance, followed by the water spray and venting rates. The simulation suggested that a material with a lower transmissivity to thermal radiation may effectively lower radiation losses, improving the kiln performance, so such materials for glazing is a high priority.

Mémoire (M.Eng.)-- Universite du Québec à Chicoutimi, 1992. / Document électronique également accessible en format PDF. CaQCU

Mémoire (M.Eng.)--Université du Québec à Chicoutimi, 1996. / Document électronique également accessible en format PDF. CaQCU

Made available in DSpace on 2014-10-09T12:52:00Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:03Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2017-04-12T16:58:50Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação_Ulysses.pdf: 2292611 bytes, checksum: 94f0d93357c24023b30a73414786b32e (MD5) / Made available in DSpace on 2017-04-12T16:58:50Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação_Ulysses.pdf: 2292611 bytes, checksum: 94f0d93357c24023b30a73414786b32e (MD5) Previous issue date: 2016-01-29 / CAPES / O processo de obtenção do gesso beta, que consiste na desidratação do minério da gipsita a uma temperatura entre 125 °C e 160°C, é realizado em fornos rotativos através de queima direta ou indireta. Os principais combustíveis utilizados neste processo no Polo Gesseiro do Araripe são a lenha, o coque de petróleo, o óleo BPF e gás natural. Esta dissertação estuda a modelagem matemática de um sistema de calcinação com aquecimento indireto utilizando dois combustíveis sólidos diferentes: a lenha e o coque de petróleo. A modelagem é feita por meio do Método dos Volumes Finitos em um modelo bidimensional de coordenadas cilíndricas. Através da simulação numérica é possível prever o perfil de temperatura em uma seção transversal do forno, tal como suas taxas de aquecimento. São observadas as influências de parâmetros como vazão mássica do combustível, percentual de excesso de ar na combustão e teor de umidade da lenha. Também é realizada uma comparação entre os processos utilizando a lenha e o coque com relação ao custo e à emissão de dióxido de enxofre (SO2). / The process of obtaining the beta plaster, which consists of dehydration of the gypsum ore under a temperature between 100°C and 160 °C, is performed in rotary kilns through direct or indirect burn. The main fuels utilized in this process at Araripe Gypsum District are firewood, petroleum coke, heavy fuel oil and natural gas. This dissertation studies the mathematical modeling of a calcination system with indirect heating using two different solid fuels: firewood and petroleum coke. The modeling is made by using the Finite Volume Method in a two-dimensional model of cylindrical coordinates. Through the simulation is possible to predict the temperature behavior in a cross section of the kiln, as well as its heating rates. It was analyzed the influence of parameter such as mass flow rate, percent excess combustion air and moisture content of the firewood. A comparison between the processes using firewood and coke is also conducted, concerning the cost and the sulfur dioxide (SO2) emission.

Made available in DSpace on 2014-10-09T12:52:00Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:03Z (GMT). No. of bitstreams: 0 / Os agregados eletrofundidos são largamente utilizados para a produção de refratários tendo em vista a melhoria geral de propriedades propiciada pelo emprego dos mesmos. Neste trabalho projetaram-se agregados eletrofundidos adequados para aplicação em refratários para a zona de queima de fornos de cimento. Para o projeto dos mesmos foi realizada inicialmente uma avaliação a alta temperatura das reações que ocorrem entre as fases refratárias e as fases presentes no clínquer de cimento Portland, visando identificar os sistemas refratários mais promissores. Em seguida foram realizadas eletrofusões de matérias primas pertencentes a estes sistemas, visando a obtenção de diferentes composições de agregados, cujas características foram avaliadas. A última etapa do desenvolvimento envolveu a escolha de alguns agregados para a formulação de refratários para a zona de queima de fornos de cimento; medindo e comparando as propriedades dos tijolos obtidos com um tijolo refratário padrão de magnésia-espinélio. Agregados pertencentes ao sistema MgO – TiO2 – CaO, mais especificamente ao triângulo de compatibilidade formado pelas fases MgO – Mg2TiO4 – CaTiO3, mostraram características adequadas para o desenvolvimento de refratários para a zona de queima de fornos de cimento. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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Leung Yuen-fun Rachel. / Thesis submitted in: May 2004. / One leaflet mounted. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references. / Abstracts in English and Chinese. / Chapter Chapter One: --- Historical Background / The discovery of the kiln sites --- p.1 / The naming of Changsha ware --- p.3 / The beginning of production --- p.5 / Chapter Chapter Two: --- Development of Changsha ware / Duration of operation --- p.10 / Stages of development --- p.11 / Reasons for decline --- p.15 / Chapter Chapter Three: --- Glaze and Kiln Characteristics of Changsha ware / Body --- p.18 / Shaping method --- p.19 / Glazes --- p.19 / Kiln --- p.21 / Chapter Chapter Four: --- Classification of Changsha ware in the Art Museum collection / Introduction --- p.24 / Daily household wares --- p.25 / Cultural and scholar's articles --- p.44 / Toys --- p.47 / Potter's tool --- p.51 / Chapter Chapter Five: --- Decoration of Changsha ware in the Art Museum collection / Introduction --- p.53 / Decorative technique --- p.54 / Decorative motif --- p.59 / Chapter Chapter Six: --- Changsha ware as reflections of daily life / Custom and religion --- p.78 / Games --- p.94 / Childhood education --- p.98 / Cross cultural Communication --- p.100 / Chapter Chapter Seven: --- Conclusion --- p.102

La forêt franc-comtoise, en particulier la forêt bisontine, a lourdement souffert de son exploitation au cours des XVIIIème et XIXème siècles, entrainant une pénurie de bois sur le territoire bisontin. Dans de nombreuses sources historiographiques et travaux de recherche, les raisons de cette pénurie apparaissent comme étant complexes et multiples. La découverte de près d'un millier de plateformes de charbonnage en forêt de Chailluz a induit toute une série de questionnements concernant la fonction de cette forêt et le rôle du charbonnage dans la pénurie de bois bisontine. Les prémices d’une étude archivistique ont permis d’identifier et de caractériser les grands consommateurs du bois du territoire bisontin durant les XVIIIème et XIXème siècles autres que l’activité charbonnière, puisque très rarement citée dans les textes. L’étude archéométrique des plateformes de la forêt de Chailluz a permis de caractériser le charbonnage de la fin de l’époque moderne, fournissant alors l’image des peuplements forestiers du XVIIIème siècle ainsi que l’impact de cette pratique sur cette forêt. / The Franche-Comté forest, in particular the forest of Besançon, suffered heavily from its exploitation during the 18th and 19th centuries, causing a wood shortage in the territory. In many historiographical sources and research, the reasons of this shortage appear to be complex and manifold. The discovery of nearly a thousand charcoal platforms in the Chailluz forest has led to a series of questions concerning the function of this forest and the role of charcoal production in the wood shortage. The first fruits of an archival study made it possible to identify and characterize the major consumers of wood in the territory of Besançon during the 18th and 19th centuries other than the charcoal production, because rarely mentioned in the literature. The archaeometric study of the Chailluz charcoal platforms made it possible to characterize the charcoal production at the end of the modern age, providing the image of the 18th century forest stands and the impact of this practice on Chailluz.

Dans les arts plastiques, le concept de la beauté doit être associé aux techniques sous-jacentes. L'artiste doit choisir et maîtriser ces techniques afin de les appliquer à l'art en vue d'atteindre les résultats esthétiques visés. Une approche scientifique de ces techniques a un rôle important dans l'amélioration de leur application dans les arts plastiques. Les céramiques et poteries sont un domaine complexe où les réactions chimiques et les propriétés physiques des argiles et des glaçures doivent être prises en compte. Dans ce domaine l'histoire de la science était un guide utile dans une telle recherche. Pour les céramiques, les réactions chimiques se produisant à la phase haute température du processus de cuisson déterminent essentiellement l'aspect final de la surface du produit. En conséquence, changer les conditions de ces réactions (profils de température, la nature de l'atmosphère du four) était une bonne méthode pour obtenir de nouveaux aspects de surface. L'atmosphère du four pendant et après la cuisson permettait de contrôler, dans une large mesure, l'aspect final des produits céramiques, et cela dépend à la fois de la conception et de la mise en place du four. L'étude de l'histoire des techniques céramiques, dans différentes civilisations, a conduis à un aperçu des techniques de cuisson. La compréhension scientifique de ces techniques a mené à des stratégies en vue de modifier la conception du four et la pratique de la cuisson. / In Plastic arts; with the concept of beauty there are also techniques, artists choose between these techniques for apply art works matching with aesthetic viewpoint. As well as science have important role in improved applied arts and fine arts techniques. In ceramics and pottery we are confronted with the chemicals reactions and physical properties of clay and glaze which have deep roots in human history, so history techniques will guide us in this research. In ceramic, chemical reactions need high temperature as condition to exist (Firingprocess), and that have main role in determined final appearance of surface treatments for ceramics forms. When the chemical reactions and physical properties which happen in firing process are responsible of final appearance and aesthetics treatments of ceramics forms, the changing of reactions conditions was used for achieving new treatments for ceramic surface beauty. The atmosphere of kiln during and after firing process whom decide the final appearance for ceramics forms, presented as technique for modifying kiln structure as afactor of enriching aesthetics treatments for ceramic surface. The history and science of ceramics techniques in some civilizations was studied to understand some firing techniques and its roles in ceramic surface esthetics. These provided evidence with experimental study to design a new kiln which can be used as a tool to enrich ceramics forms aesthetically