Download or read book The Stability Limits of Methane Combustion Inside a Porous Ceramic Matrix written by W. D. Evans and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental stability limits of methane combustion inside a porous ceramic matrix written by William David Evans and published by . This book was released on 1991 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Methane Combustion over Lanthanum based Perovskite Mixed Oxides written by Hamidreza Arandiyan and published by Springer. This book was released on 2015-05-18 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents current research into the catalytic combustion of methane using perovskite-type oxides (ABO3). Catalytic combustion has been developed as a method of promoting efficient combustion with minimum pollutant formation as compared to conventional catalytic combustion. Recent theoretical and experimental studies have recommended that noble metals supported on (ABO3) with well-ordered porous networks show promising redox properties. Three-dimensionally ordered macroporous (3DOM) materials with interpenetrated and regular mesoporous systems have recently triggered enormous research activity due to their high surface areas, large pore volumes, uniform pore sizes, low cost, environmental benignity, and good chemical stability. These are all highly relevant in terms of the utilization of natural gas in light of recent catalytic innovations and technological advances. The book is of interest to all researchers active in utilization of natural gas with novel catalysts. The research covered comes from the most important industries and research centers in the field. The book serves not only as a text for researcher into catalytic combustion of methane, 3DOM perovskite mixed oxide, but also explores the field of green technologies by experts in academia and industry. This book will appeal to those interested in research on the environmental impact of combustion, materials and catalysis.

Download or read book Experimental analysis of radiation for methane combustion within a porous medium burner written by Vivek Krishnakumar Khanna and published by . This book was released on 1992 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Study of Emissions and Radiation for Methane Combustion Within a Porous Medium Burner written by Chengzong Li and published by . This book was released on 2005 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Combustion Processes in Propulsion written by Gabriel Roy and published by Butterworth-Heinemann. This book was released on 2006 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical propulsion comprises the science and technology of using chemical reactions of any kind to create thrust and thereby propel a vehicle or object to a desired acceleration and speed. Cumbustion Processes in Propulsion focuses on recent advances in the design of very highly efficient, low-pollution-emitting propulsion systems, as well as advances in testing, diagnostics and analysis. It offers unique coverage of Pulse Detonation Engines, which add tremendous power to jet thrust by combining high pressure with ignition of the air/fuel mixture. Readers will learn about the advances in the reduction of jet noise and toxic fuel emissions-something that is being heavily regulated by relevant government agencies. Lead editor is one of the world's foremost combustion researchers, with contributions from some of the world's leading researchers in combustion engineering Covers all major areas of chemical propulsion-from combustion measurement, analysis and simulation, to advanced control of combustion processes, to noise and emission control Includes important information on advanced technologies for reducing jet engine noise and hazardous fuel combustion emissions

Download or read book Multidimensional modelling and calculation of combustion in porous media written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Em comparação a sistemas de aquecimento domésticos que utilizam queimadores convencionais de chama não confinada, queimadores baseados na técnica de combustão em pré-mistura no interior de meios porosos caracterizam-se pela compacidade, pela elevada eficiência térmica e pela alta razão de operação, isto é, a razão entre a máxima e a mínimapotências entre as quais pode operar de modo estável. Além disso, queimadores porosos, nos quais a chama permanence ancorada no interior dos poros da camada de suporte da chama, apresentam reduzida formação de poluentes, em particular de CO e NOx, e possibilitam a queima de misturas mais pobres ou de combustíveis de mais baixo poder calorífico. A modelação numérica desempenha um importante papel no desenvolvimento de queimadores porosos, permitindo a verificação, a priori, de novas propostas ou da introduçãode modificações em configurações existentes. Nesta dissertação são apresentados e discutidos os modelos físico-matemáticos e numéricos desenvolvidos para o estudo de uma nova concepção de queimador poroso, o qual consiste de uma placa fina de espuma cerâmica (carbeto de silício) de alta porosidade precedida por uma placa de material isolante térmico (alumina) finamente perfurada, apresentando uma baixa porosidade equivalente. Devido às características construtivas do novo queimador, em particular a diferença de porosidade entre as camadas difusora e de suporte da chama, e também ao facto de acâmara de combustão estar sendo desenvolvida para operar acoplada a um sistema inovador de vaporização, à saída do qual a mistura ar-combustível pode não se encontrarperfeitamente homogeneizada, estudos foram conduzidos com o objectivo de investigar os fenómenos oriundos da imersão de uma placa de espuma cerâmica porosa em um escoamento. Inicialmente, a dispersão de um escalar no escoamento através de um meio poroso é considerada. Este estudo, no qual se faz uso de modelos uni e bidimensionais do escoamento em meio poroso, mostra que o modelo de Koch e Brady (1985), desenvolvido para a dispersão de um escalar em escoamentos de baixa velocidade através de leitos empacotados de esferas, reproduz os resultados da dispersão de um tracer no escoamento numa espuma cerâmica ao se considerar o efeito da espessura da placa porosa na direcção do escoamento e introduzir o diâmetro de poro como comprimento caraterístico. Com base nos resultadosdeste estudo, um modelo para a conductividade efectiva da placa perfurada como um meio poroso de baixa porosidade é obtido. Adicionalmente, a estabilidade de um escoamento isotérmico na interface de entrada de uma espuma cerâmica imersa num escoamento é investigada, apresentando-se a comparação de dois modelos para o escoamento turbulento no interior de meios porosos disponíveis na literatura. Considerando o escoamento através de uma placa de espuma cerâmica inserida num tubo recto e a jusante de uma expansão súbita, é mostrado que o modelo de Antohe e Lage (1997) prevê a relaminarização do escoamento logo após a entrada no meio poroso, enquanto o modelo de Pedras e de Lemos (2001) indica que a turbulência do escoamento pode ser destruída ou aumentada, em função da condição de turbulência doescoamento na secção de entrada da placa porosa. Ainda nesta análise do escoamento nas regiões de interface do escoamento num meio poroso, um estudo sobre a estabilidade de chama na região de interface entre as placas porosas é apresentado. Por meio de cálculos tridimensionais da câmara de combustão, é mostrada a importância da correcta especificação do diâmetro dos furos da placa perfurada para se evitar a ocorrência de flashback da chama para a região a montante da câmara de combustão. Um modelo tridimensional foi desenvolvido para estudar o desempenho do novo queimador poroso. Este modelo consiste na solução numérica das equações de Navier-Stokese dos balanços de energia e de massa das espécies químicas. O modelo considera a radiação térmica na espuma cerâmica e o não equilíbrio térmico local entre as duas fases. Mecanismosde reacção detalhados são aplicados para modelar a oxidação de metano e heptano, permitindo o cálculo da formação de poluentes. A validação do modelo foi efectuadacomparando-se previsões com resultdos experimentais do queimador operando com metano como combustível. O desempenho do queimador foi calculado utilizando heptano como combustível modelo. A influência das condições operacionais sobre a estabilização e a estrutura da chama, sobre o escoamento, e sobre a formação de poluentes é discutida. Dentre outros resultados, é observado que a frente de chama é estabilizada no interior da camada de espuma de carbeto de silício para toda a faixa de operação, e que a formação prevista de CO e NOx está compreendida nos limites observados na operação de equipamentos similares operados com outros combustíveis líquidos.

Download or read book Masters Theses in the Pure and Applied Sciences written by Wade H. Shafer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) * at Purdue University in 1 957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all con cerned if the printing and distribution of the volumes were handled by an interna tional publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Cor poration of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 36 (thesis year 1991) a total of 11,024 thesis titles from 23 Canadian and 161 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this important annual reference work. While Volume 36 reports theses submitted in 1991, on occasion, certain univer sities do report theses submitted in previous years but not reported at the time.

Download or read book AIAA SAE ASME ASEE 27th Joint Propulsion Conference 91 1960 91 2017 written by and published by . This book was released on 1991 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Computational and Experimental Investigation of Flow and Combustion Physics in Porous Media written by Sadaf Sobhani and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: As emission regulations become increasingly more stringent and policies evolve to combat global climate change impacts, reducing pollutant and greenhouse gas emissions emerge as one of the most important goals of combustion research. Techniques such as staged combustion, lean premixed combustion, catalytic combustion, and advanced mixing and fuel atomization are some of the methods examined to reduce emissions of pollutants such as nitrogen oxides (NOx), carbon monoxide (CO), and unburned hydrocarbons (UHCs). Porous media combustion represents an advanced combustion concept that is capable of achieving low emissions, enhanced flame stabilization, and improved fuel efficiency. Conventionally, Porous Media Burners (PMBs) utilize a two-zone ``step" burner design, which operates on the principal that the upstream high pore-density region serves as a flame arrestor and flame stability is observed at the interface between the two regions of high and low pore density. This dissertation contributes to the analysis of combustion in porous media, characterization of its performance in conventional PMBs, and the development and testing of a novel porous matrix design for enhanced combustion performance. First, a characterization of the combustion stability, pressure drop and pollutant emissions of conventional two-zone ``step" PMB is presented for a range of operating conditions and burner designs. Long-term material durability tests at steady-state and cycled on-off conditions were performed under operation with methane-fuel at atmospheric pressure. Thermocouple temperature measurements and pressure drop data are presented and compared to results obtained from 1D volume-averaged simulations. Additionally, the burner design with the maximum combustion stability regime was identified and tested in subsequent high-pressure experiments at 2, 8, and 20 bar with fully vaporized and preheated n-heptane and methane fuels, at fuel-lean equivalence ratios. Second, in an effort to expand the combustion stability regime beyond the capability of two-zone ``step" PMBs, a novel burner design having a spatially graded porous matrix is proposed, resulting from the theoretical analysis of the governing equations and constitutive relations. This analysis reveals the significance of the pore topology on interphase heat exchange and radiative heat transfer properties, quantified by the local Stanton number and optical depth, respectively. Gradation in topology (i.e. porosity, pore diameter, cell diameter, etc.) enables the flame to stabilize dynamically within the porous matrix and for a wider range of operating conditions. Computational stability maps, temperature profiles, and emissions data are presented for comparable two-zone ``step'' and ``graded" burner concepts, which predict significant performance enhancements in the latter. The theoretical and computational investigation of matrix gradation in PMBs as well as experiments reveal the potential for tailoring the internal heat transfer properties to optimize performance, and thus motivates the subsequent work in leveraging recent advancements in additive manufacturing to enable smoothly graded porous structures. The next part of this dissertation achieves the use of Lithography-based Ceramic Manufacturing for the fabrication of functionally graded matrix structures, designed using periodic surface equations. The manufactured samples were operated in a PMB over a range of operating conditions to test the feasibility and performance of additive manufactured materials in PMBs. Thermal and durability testing of the manufactured parts are characterized, along with combustion stability maps from the ``step" and ``graded" PMB experiment, which, consistent with the previous theoretical, computational, and experimental results, show significant performance improvements of the ``graded" burner.

Download or read book Fundamentals and Technology of Combustion written by F El-Mahallawy and published by Elsevier. This book was released on 2002-07-10 with total page 863 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals and Technology of Combustion contains brief descriptions of combustion fundamental processes, followed by an extensive survey of the combustion research technology. It also includes mathematical combustion modeling of the processes covering mainly premixed and diffusion flames, where many chemical and physical processes compete in complex ways, for both laminar and turbulent flows. The combustion chemistry models that validate experimental data for different fuels are sufficiently accurate to allow confident predictions of the flame characteristics. This illustrates a unique bridge between combustion fundamentals and combustion technology, which provides a valuable technical reference for many engineers and scientists. Moreover, the book gives the reader sufficient background of basic engineering sciences such as chemistry, thermodynamics, heat transfer and fluid mechanics. The combustion research and mathematical models fit between small-scale laboratory burner flames, and large-scale industrial boilers, furnaces and combustion chambers. The materials have been collected from previous relevant research and some selected papers of the authors and co-workers, which have been presented mainly in different refereed journals, international conferences and symposia, thus providing a comprehensive collection. Furthermore, the book includes some of the many recent general correlations for the characteristics of laminar, turbulent, premixed and diffusion flames in an easily usable form. The authors believe that further progress in optimizing combustion performance and reducing polluting emissions can only be treated through understanding of combustion chemistry.

Download or read book Perovskite Catalysts Enhanced Combustion on Porous Media and Thermoelectric Power Conversion written by Manuel David Robayo and published by . This book was released on 2013 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of La-Sr-Fe-Cr-Ru based perovskite catalysts, on matrix stabilized combustion in a porous ceramic media were also explored. Highly porous silicon carbide ceramics are used as a porous media for a catalytically enhanced superadiabatic combustion of a lean mixture of methane and air. Perovskite catalytic enhancement of SiC porous matrix with La0.--5Sr0.25Fe0.6Cr0.35Ru0.05O3, La0.--5Sr0.25Fe0.6Cr0.4O3, La0.--5Sr0.25Fe0.95Ru0.05O3, La0.--5Sr0.05Cr0.95Ru0.05O3, and LaFe0.95Ru0.05O3 were used to enhance combustion. The flammability limits of the combustion of methane and air were explored using both inert and catalytically enhanced surfaces of the porous ceramic media. By coating the SiC porous media with perovskite catalysts it was possible to lower the minimum stable equivalence ratio and achieve more efficient combustion.

Download or read book Proceedings of the Engineering Technology Conference on Energy written by and published by . This book was released on 2001 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Masters Theses in the Pure and Applied Sciences written by W. H. Shafer and published by Springer Science & Business Media. This book was released on 1993 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume 36 reports (for thesis year 1991) a total of 11,024 thesis titles from 23 Canadian and 161 US universities. The organization of the volume, as in past years, consists of thesis titles arranged by discipline, and by university within each discipline. The titles are contributed by any and all a

Download or read book Proceedings of the 30th 1995 National Heat Transfer Conference written by Alfonso Ortega (Ph. D.) and published by . This book was released on 1995 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 974 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Direct Methane to Methanol written by Vladimir Arutyunov and published by Elsevier. This book was released on 2014-01-30 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: Direct Methane to Methanol: Foundations and Prospects of the Process offers a state-of-the-art account of one of the most interesting and potentially commercial technologies for direct conversion of natural gas into valuable chemicals. The book thoroughly explains the complex and unusual chemistry of the process, as well as possible applications for direct methane to methanol (DMTM). It covers topics involving thermokinetics, pressure, direct oxidation of heavier alkanes, and more, and provides detailed appendices with experimental data and product yields. This book provides all those who work in the field of gas processing and gas chemistry with the theory and experimental data to develop and apply new processes based on direct oxidation of natural gas. All those who deal with oil and natural gas production and processing will learn about this promising technology for the conversion of gas into more valuable chemicals. Reviews more than 350 publications on high-pressure, low-temperature oxidation of methane and other gas phase hydrocarbons Contains rare material available for the first time in English Explains the reasons of previous failure and outlines the way forward for commercial development of the conversion technology Presents a deep theoretical knowledge of this complex conversion process