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Sample records for evaporacion utilizando combustibles

  1. Comparative study on systems of residual water treatment in the process industry by evaporation, using fossils fuels or solar energy; Estudio comparativo sobre sistemas de tratamiento de aguas residuales de la industria de procesamiento por evaporacion, utilizando combustibles fosiles o energia solar

    Energy Technology Data Exchange (ETDEWEB)

    Landgrave Romero, Julio; Canseco Contreras, Jose [Facultad de Quimica, UNAM (Mexico)

    1996-07-01

    The residual water treatment of the process industry, nowadays is an imminent necessity in our country. In the present study two different forms are considered to concentrate residual waters: multiple effect evaporation and solar evaporation. The use of solar evaporation lagoons is a good possibility to conserving energy by means of the diminution of fossil fuel consumption. The design basis of the evaporation systems via multiple effect, as well as solar evaporation, the results of the respective sizing and the estimation of the corresponding costs are presented. A practical case is described on the cooking of cotton linters (flock) [Spanish] El tratamiento de aguas residuales de la industria de proceso, hoy en dia es una necesidad inminente en nuestro pais. En el presente trabajo se consideran dos formas distintas para concentrar las aguas residuales: evaporacion de multiple efecto y evaporacion solar. El empleo de lagunas de evaporacion solar es una buena posibilidad para conseguir el ahorro de energia mediante disminucion del consumo de combustibles fosiles. Se presentan las bases de diseno de los sistemas de evaporacion via multiple efecto, asi como solar, los resultados del dimensionamiento respectivo y la estimacion de los costos correspondientes. Se describe un caso practico sobre el cocido de linters de algodon (borra)

  2. Combustion

    CERN Document Server

    Glassman, Irvin

    1987-01-01

    Combustion, Second Edition focuses on the underlying principles of combustion and covers topics ranging from chemical thermodynamics and flame temperatures to chemical kinetics, detonation, ignition, and oxidation characteristics of fuels. Diffusion flames, flame phenomena in premixed combustible gases, and combustion of nonvolatile fuels are also discussed. This book consists of nine chapters and begins by introducing the reader to heats of reaction and formation, free energy and the equilibrium constants, and flame temperature calculations. The next chapter explores the rates of reactio

  3. PRODUCCIÓN DE ELECTRICIDAD EN CELDAS DE COMBUSTIBLE MICROBIANAS UTILIZANDO AGUA RESIDUAL: EFECTO DE LA DISTANCIA ENTRE ELECTRODOS

    Directory of Open Access Journals (Sweden)

    Germán Buitrón

    2011-01-01

    Full Text Available Se evaluó la influencia de la separación de electrodos sobre la producción de electricidad y la eliminación de materia orgánica en celdas de combustible microbianas usando agua residual. Para ello se construyeron tres celdas de geometría semejante pero con diferente volumen. En promedio, se obtuvo una eficiencia de eliminación de materia orgánica del 71%. La duración del ciclo fue de 0.97 días para la celda de 40 mL, 1.03 días para la celda de 80 mL y 5.93 días para la celda de 120 mL. El aumento de distancia entre los electrodos (4, 8 y 12 cm no causó un efecto negativo en la generación de electricidad, pues en la mayor separación (celda de 120 mL se alcanzó un voltaje máximo de 660 mV, mientras que para las celdas de 40 y 80 mL fue de 540 mV y 532 mV, respectivamente. La densidad de potencia máxima se presentó en la celda con separación de 12 cm (408 mW/m2. Sin embargo, se observó que la potencia volumétrica disminuyó a medida que aumentó la separación entre los electrodos.

  4. Thermochemical of combustion products using thermodynamic properties obtained of statistical mechanics; Termoquimica dos produtos de combustao utilizando propriedades termodinamicas obtidas da mecanica estatistica

    Energy Technology Data Exchange (ETDEWEB)

    Pimentel, Carlos Alberto Rocha [Instituto Tecnologico de Aeronautica, Sao Jose dos Campos, SP (Brazil). Inst. de Engenharia Aeronautica; Hinckel, Jose Nivaldo; Koreeda, Jorge [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Div. de Mecanica Espacial e Controle]. E-mail: carlosal@aer.ita.cta.br; hinckel@sigma.dem.inpe.br

    1997-07-01

    This work presents the results of an analytical model and a computer program to obtain thermochemical properties of combustion products in a liquid rocket motors, using the method of statistical mechanic to calculation thermodynamic properties of the species. The equations of statistical mechanics and the technique of minimizing of Gibbs free energy are used to calculate the thermochemical functions and the equilibrium chemical composition. These methods are applied to the calculation of equilibrium properties of the combustion products in liquid rocket motors for different propellant pairs, O/F ratios and chamber pressures. The results obtained from this method are compared to those of NASA SP-273. (author)

  5. Consumption and combustion efficiency in a generator engine using biodiesel; Consumo e eficiencia de combustao em um motor gerador utilizando biodisel

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Joao Paulo Barreto; Delmond, Josue G.; Couto, Rodney Ferreira; Neiva Filho, Neyber Cristiano; Reis, Elton F. dos [Universidade Estadual de Goias (UNUCET/UEG), Anapolis, GO (Brazil). Unidade Universitaria de Ciencias Exatas e Tecnologicas], Email: bcunha_2@hotmail.com

    2011-07-01

    Due to the increasing demand for biodiesel, associated to the aim of reduction in pollutants emissions, technical feasibility studies are increasingly needed. This study aimed to evaluate the use of biodiesel in different concentrations (B5, B10, B20, B50, B75 and B100) in a diesel generator set, with an engine with 3,73 KW four-stroke with direct injection. Assays were performed to quantify the hourly fuel consumption and emission of gases under different conditions of engine operation, through demands of electrical loads (500 W, 1.000W, 1.500W, 2,000 W and off) connected to the generator group. A completely randomized design was used with 5x6 factorial arrangement of treatment, six of biodiesel blends and five electric load demands, with three repetitions. The results demonstrated that the mixtures showed a significant difference in fuel consumption and combustion efficiency, and revealed that the use of biodiesel in higher concentrations in general provided a combustion process more efficient compared to conventional diesel. (author)

  6. Estimate potential evaporation and solar radiation in the Yaqui valley, Sonora, Mexico, using data from satellite; Estimacion de evaporacion y radiacion solar en el valle del Yaqui, Sonora, usando datos de satelite

    Energy Technology Data Exchange (ETDEWEB)

    J Watts, Christopher; Rodriguez, Julio Cesar [Instituto del Medio Ambiente y el Desarrollo sustentable del estado de Sonora (Mexico); Garatuza Payan, Jaime [Instituto Tecnologico de Sonora (Mexico); Henk de Bruin [Universidad Agricola de Wageningen (Netherlands); Stewart, John [Universidad de Southampton (United Kingdom)

    1999-12-01

    The data from tow automatic weather stations in the Yaqui valley were used to estimate potential evaporation using the Makkink formula, based on observed incoming solar radiation and climatological values of air temperature. The usefulness of this formula was assessed by comparison with the Penman-Monteith, Penman and Priestley-Taylor formula and measurements of net radiation. A methodology was presented for estimating incoming solar radiation using visible band data from the GOES satellite. Comparisons against ground-based measurements from two pyranometers installed in the Yaqui valley gave good results, particularly in months with low cloud cover. Images for August 1993 were used to produce a map of the spatial distribution of potential evaporation. [Spanish] Para calcular la evaporacion potencial en el valle del Yaqui, usando la formula de Makkink, se utilizaron datos de dos estaciones meteorologicas automaticas. La mencionada formula se basa en la radiacion solar incidente observada y en ciertos valores climatologicos de temperatura del aire. Se evaluo la utilidad de esta formula, comparandola con las de Penman-Monteith, Pennan y Priestley-Taylor, asi como con mediciones de radiacion neta. Se desarrollo una metodologia para estimar la radiacion solar incidente usando la banda visible del satelite GOES. Se hizo una comparacion con mediciones de dos piranometros instalados en el valla del Yaqui, obteniendose buenos resultados, principalmente en meses con poca nubosidad. Se utilizaron imagenes de agosto de 1993 para producir un mapa de la distribucion espacial de la evaporacion potencial.

  7. High energy milling of alumina synthesized by combustion reaction using attritor mill vertical axis: influence of rotation speed; Moagem de alta energia de alumina sintetizada por reacao de combustao utilizando moinho atritor de eixo vertical: influencia da velocidade de rotacao

    Energy Technology Data Exchange (ETDEWEB)

    Silva, M.C. da; Silva, F.N.; Costa, A.C.F.M. [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais; Costa, G.B. [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Unidade Academica de Engenharia de Producao; Freitas, N.L. de, E-mail: normanda@ufcg.edu.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Unidade Academica de Tecnologia do Desenvolvimento

    2014-07-01

    The use of a reactive high energy milling for the synthesis of ceramic powders of metal oxides, carbides, borides, nitrides or mixtures of ceramics or ceramic and metal compounds have been widely reported. The objective of this study is to assess how high energy ball milling (not reactive) using different rotations, 300, 400 and 500 rpm, alter the structure and morphology of alpha-alumina powders synthesized by combustion reaction. Time and temperature of the combustion reaction has been reported for the synthesis of aluminas. The samples of unmilled and milled alumina were characterized by XRD, SEM and particle size analysis. The results showed that the maximum reaction temperature reached was 598°C. The variation of the rotation of the mill did not affect the majority alpha-Al2O3 by stable crystal phase all samples. The median particle diameter of the milled samples at different speeds decreased with respect to unground sample. (author)

  8. Synthesis of SrBi{sub 2}Ta{sub 2}O{sub 9} by combustion synthesis; Obtencao do SrBi{sub 2}Ta{sub 2}O{sub 9} utilizando a sintese por combustao

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, F.F.; Bergmann, C.P. [Universidade Federal do Rio Grande do Sul (LACER/UFRGS), Porto Alegre, RS (Brazil). Dept. de Materiais. Lab. de Materiais Ceramicos; Sousa, V.C. [Universidade Federal do Rio Grande do Sul (LABIOMAT/UFRGS), Porto Alegre, RS (Brazil). Dept. de Materiais. Lab. de Materiais de Biomateriais

    2009-07-01

    The combustion synthesis is a low cost technique for obtaining homogeneous nanostructured compounds with high purity. The ferroelectric memory devices have been widely studied by the electronics industry by presenting high-speed recording, read and rewrite. The PZT, in the form of thin films, is the ceramic materials most used for this purpose, but it presents ferroelectric fatigue. The SrBi{sub 2}Ta{sub 2}O{sub 9} has a high cycle enables the recording which is good applicability in the PZT. Therefore, this work aims to obtain the SrBi{sub 2}Ta{sub 2}O{sub 9} using the combustion synthesis and urea as a reducing agent. The characterization of the powder was realized used the technique of x-ray diffraction (XRD) to determine the phases present and to evaluate surface area by the BET method. The powder obtained after synthesis showed low crystallinity presenting just the BiOCl like the crystalline phase present, but heat treatment at 800 deg C for 2 hours was sufficient for the formation of SrBi{sub 2}Ta{sub 2}O{sub 9} . (author)

  9. Mass transport in a PEMFC fuel battery using combinations of monopolar plates and reaction-diffusion medium; Transporte de masa en una pila a combustible tipo PEMFC utilizando combinaciones de platos monopolares y medios de difusion de reactivos

    Energy Technology Data Exchange (ETDEWEB)

    Rosas Paleta, M. G. Araceli [Benemerita Universidad Autonoma de Puebla, Puebla, Puebla (Mexico); Bautista Rodriguez, C. Moises [Alter-Energias Puebla, Puebla (Mexico)] email: celso.bautista@thyssenkrupp.com; Rivera Marquez, J. Antonio; Tepale Ochoa, Nancy [Benemerita Universidad Autonoma de Puebla, Puebla, Puebla (Mexico)

    2009-09-15

    The efficiency of a PEMFC fuel battery is limited due to a variety of mass transport-related phenomena that take place while it is operating. The electromotive force of the PEM fuel battery is related to the generation of concentration gradients resulting from the distribution of the reactants on the active sites of the electrode. The reactant gases supplied to the PEMFC are distributed over the diffusion layer of the electrodes through the channels of the polar plates. They then spread toward the active layer where the semi-reactions take place. Another important aspect is the presence of water molecules, a product of the reaction. When they accumulate, they cover the porosity of the electrodes, involving the reduction in the flow of reactants, even at high current density values and, combined with the diffusion phenomena involved, cause the PEMFC to complete cease functioning. The critical parameters for the transport phenomena are porosity, the diameter of the pore in the diffusion layer and the characteristics of the distribution of the reactants. The present works includes an experimental design of two distribution media and two diffusion media of the reactant gases in a PEMFC, involving three case studies. The results show significantly notable interactions between the diameter of the pore, the type of diffusion layer applied and the type of distributor applied. The combination in the second case significantly reduces the ohmic resistance and moderately reduces the diffusion resistances. While the combination in case three notably increases the ohmic resistance, diffusion resistance is significantly reduced. [Spanish] La eficiencia de una pila a combustible tipo PEMFC es limitada por diversos fenomenos de transporte de masa presentes durante su funcionamiento. La fuerza electromotriz de la pila a combustible tipo PEM esta relacionada con la generacion de gradientes de concentracion los cuales se dan como resultado de la distribucion de los reactivos sobre los

  10. Smoldering Combustion

    OpenAIRE

    Rein, G

    2016-01-01

    Smoldering combustion is the slow, low temperature, flameless burning of porous fuels and is the most persistent type of combustion phenomena. It is especially common in porous fuels which form a char on heating, like cellulosic insulation, polyurethane foam or peat. Smoldering combustion is among the leading causes of residential fires, and it is a source of safety concerns in industrial premises as well as in commercial and space flights. Smoldering is also the dominant combustion phenomena...

  11. Computational Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Westbrook, C K; Mizobuchi, Y; Poinsot, T J; Smith, P J; Warnatz, J

    2004-08-26

    Progress in the field of computational combustion over the past 50 years is reviewed. Particular attention is given to those classes of models that are common to most system modeling efforts, including fluid dynamics, chemical kinetics, liquid sprays, and turbulent flame models. The developments in combustion modeling are placed into the time-dependent context of the accompanying exponential growth in computer capabilities and Moore's Law. Superimposed on this steady growth, the occasional sudden advances in modeling capabilities are identified and their impacts are discussed. Integration of submodels into system models for spark ignition, diesel and homogeneous charge, compression ignition engines, surface and catalytic combustion, pulse combustion, and detonations are described. Finally, the current state of combustion modeling is illustrated by descriptions of a very large jet lifted 3D turbulent hydrogen flame with direct numerical simulation and 3D large eddy simulations of practical gas burner combustion devices.

  12. Combustion engineering

    CERN Document Server

    Ragland, Kenneth W

    2011-01-01

    Introduction to Combustion Engineering The Nature of Combustion Combustion Emissions Global Climate Change Sustainability World Energy Production Structure of the Book   Section I: Basic Concepts Fuels Gaseous Fuels Liquid Fuels Solid Fuels Problems Thermodynamics of Combustion Review of First Law Concepts Properties of Mixtures Combustion StoichiometryChemical EnergyChemical EquilibriumAdiabatic Flame TemperatureChemical Kinetics of CombustionElementary ReactionsChain ReactionsGlobal ReactionsNitric Oxide KineticsReactions at a Solid SurfaceProblemsReferences  Section II: Combustion of Gaseous and Vaporized FuelsFlamesLaminar Premixed FlamesLaminar Flame TheoryTurbulent Premixed FlamesExplosion LimitsDiffusion FlamesGas-Fired Furnaces and BoilersEnergy Balance and EfficiencyFuel SubstitutionResidential Gas BurnersIndustrial Gas BurnersUtility Gas BurnersLow Swirl Gas BurnersPremixed-Charge Engine CombustionIntroduction to the Spark Ignition EngineEngine EfficiencyOne-Zone Model of Combustion in a Piston-...

  13. Energy analysis of the production process of sugar using modern technologies of process integration; Analisis energetico del proceso de produccion del azucar utilizando tecnicas modernas de integracion de proceso

    Energy Technology Data Exchange (ETDEWEB)

    Figueroa Ibarra, Luis; Arriola Medellin, Alejandro [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    1999-07-01

    The application of new concepts for the energy analysis of industrial processes, which consider the thermal integration of the process equipment, not only allows to detect energy recovery potentials that cannot be visualized with the traditional treatment of energy diagnosis of individual equipment, allows in addition, to suggest changes in the operation of the process that, without modifying the production, result in the reduction of the consumption of energy by the services and fuel. The analysis of thermal integration is illustrated for the case of a sugar mill, detecting a reduction potential in the use of fuel oil of 75%, and a potential increase of electrical production by cogeneration of 41%, departing from the modification of the use of the steam available in the process, and of the change of operation parameters of operation in the evaporation section. [Spanish] La aplicacion de nuevos conceptos para el analisis energetico de procesos industriales, los cuales consideran la integracion termica de los equipos del proceso, no unicamente permiten detectar potenciales de recuperacion de energia que no se pueden visualizar con el tratamiento tradicional de diagnostico energetico de equipos individuales, permiten ademas, sugerir cambios en la operacion del proceso que, sin modificar la produccion, redundan en una reduccion del consumo de servicios y combustible. El analisis de la integracion termica se ilustra para el caso de un ingenio azucarero, detectandose un potencial de reduccion del uso de combustoleo de 75%, y un potencial de incremento de produccion electrica por cogeneracion de 41%, a partir de la modificacion del uso del vapor disponible en el proceso, y del cambio de parametros de operacion en la seccion de evaporacion.

  14. Bubble Combustion

    Science.gov (United States)

    Corrigan, Jackie

    2004-01-01

    A method of energy production that is capable of low pollutant emissions is fundamental to one of the four pillars of NASA s Aeronautics Blueprint: Revolutionary Vehicles. Bubble combustion, a new engine technology currently being developed at Glenn Research Center promises to provide low emissions combustion in support of NASA s vision under the Emissions Element because it generates power, while minimizing the production of carbon dioxide (CO2) and nitrous oxides (NOx), both known to be Greenhouse gases. and allows the use of alternative fuels such as corn oil, low-grade fuels, and even used motor oil. Bubble combustion is analogous to the inverse of spray combustion: the difference between bubble and spray combustion is that spray combustion is spraying a liquid in to a gas to form droplets, whereas bubble combustion involves injecting a gas into a liquid to form gaseous bubbles. In bubble combustion, the process for the ignition of the bubbles takes place on a time scale of less than a nanosecond and begins with acoustic waves perturbing each bubble. This perturbation causes the local pressure to drop below the vapor pressure of the liquid thus producing cavitation in which the bubble diameter grows, and upon reversal of the oscillating pressure field, the bubble then collapses rapidly with the aid of the high surface tension forces acting on the wall of the bubble. The rapid and violent collapse causes the temperatures inside the bubbles to soar as a result of adiabatic heating. As the temperatures rise, the gaseous contents of the bubble ignite with the bubble itself serving as its own combustion chamber. After ignition, this is the time in the bubble s life cycle where power is generated, and CO2, and NOx among other species, are produced. However, the pollutants CO2 and NOx are absorbed into the surrounding liquid. The importance of bubble combustion is that it generates power using a simple and compact device. We conducted a parametric study using CAVCHEM

  15. Biofuels combustion.

    Science.gov (United States)

    Westbrook, Charles K

    2013-01-01

    This review describes major features of current research in renewable fuels derived from plants and from fatty acids. Recent and ongoing fundamental studies of biofuel molecular structure, oxidation reactions, and biofuel chemical properties are reviewed, in addition to combustion applications of biofuels in the major types of engines in which biofuels are used. Biofuels and their combustion are compared with combustion features of conventional petroleum-based fuels. Two main classes of biofuels are described, those consisting of small, primarily alcohol, fuels (particularly ethanol, n-butanol, and iso-pentanol) that are used primarily to replace or supplement gasoline and those derived from fatty acids and used primarily to replace or supplement conventional diesel fuels. Research efforts on so-called second- and third-generation biofuels are discussed briefly.

  16. Turbulent combustion

    Energy Technology Data Exchange (ETDEWEB)

    Talbot, L.; Cheng, R.K. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    Turbulent combustion is the dominant process in heat and power generating systems. Its most significant aspect is to enhance the burning rate and volumetric power density. Turbulent mixing, however, also influences the chemical rates and has a direct effect on the formation of pollutants, flame ignition and extinction. Therefore, research and development of modern combustion systems for power generation, waste incineration and material synthesis must rely on a fundamental understanding of the physical effect of turbulence on combustion to develop theoretical models that can be used as design tools. The overall objective of this program is to investigate, primarily experimentally, the interaction and coupling between turbulence and combustion. These processes are complex and are characterized by scalar and velocity fluctuations with time and length scales spanning several orders of magnitude. They are also influenced by the so-called {open_quotes}field{close_quotes} effects associated with the characteristics of the flow and burner geometries. The authors` approach is to gain a fundamental understanding by investigating idealized laboratory flames. Laboratory flames are amenable to detailed interrogation by laser diagnostics and their flow geometries are chosen to simplify numerical modeling and simulations and to facilitate comparison between experiments and theory.

  17. Tubular combustion

    CERN Document Server

    Ishizuka, Satoru

    2014-01-01

    Tubular combustors are cylindrical tubes where flame ignition and propagation occur in a spatially confined, highly controlled environment, in a nearly flat, elongated geometry. This allows for some unique advantages where extremely even heat dispersion is required over a large surface while still maintaining fuel efficiency. Tubular combustors also allow for easy flexibility in type of fuel source, allowing for quick changeover to meet various needs and changing fuel pricing. This new addition to the MP sustainable energy series will provide the most up-to-date research on tubular combustion--some of it only now coming out of private proprietary protection. Plentiful examples of current applications along with a good explanation of background theory will offer readers an invaluable guide on this promising energy technology. Highlights include: * An introduction to the theory of tubular flames * The "how to" of maintaining stability of tubular flames through continuous combustion * Examples of both small-scal...

  18. Advanced Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Holcomb, Gordon R. [NETL

    2013-03-11

    The activity reported in this presentation is to provide the mechanical and physical property information needed to allow rational design, development and/or choice of alloys, manufacturing approaches, and environmental exposure and component life models to enable oxy-fuel combustion boilers to operate at Ultra-Supercritical (up to 650{degrees}C & between 22-30 MPa) and/or Advanced Ultra-Supercritical conditions (760{degrees}C & 35 MPa).

  19. Determinación de parámetros para obtener valores de eficiencia representativos para la enseñanza de las energías renovables (solar, eólica, hidrógeno-electrólisis y pilas de combustible) utilizando el equipo de laboratorio Clean Energy Trainer

    OpenAIRE

    Mallaguari Barros, Alan Felipe; Shicay Arias, Freddy Rolando

    2015-01-01

    Este proyecto presenta un análisis detallado de las energías renovables mediante el uso del equipo CLEAN ENERGY TRAINER, el cual ofrece la posibilidad de realizar prácticas con módulos solares, generador eólico, electrólisis y pila de combustible; éstas son energías limpias y de fuente inagotable. En las prácticas se estudiarán las variables que intervienen en cada sistema, además de variar las mismas para obtener distintos resultados y determinar en qué condiciones existe mayor eficiencia...

  20. Contribución al desarrollo e introducción de combustibles gaseosos renovables mediante la caracterización termodinámica de mezclas de sus componentes utilizando un densímetro de flotador de suspensión magnética optimizado

    OpenAIRE

    Mondéjar Montagud, María Engracia

    2012-01-01

    En esta tesis se trata la caracterización termodinámica de mezclas gaseosas binarias relacionadas con los combustibles alternativos a través de la medida de gran precisión de la densidad mediante un densímetro de flotador sencillo con acoplamiento magnético. Previamente a las medidas se realizaron una serie de modificaciones del equipo con el fin de reducir las principales fuentes de incertidumbre de cada magnitud medida. Una vez realizadas las mejoras se procedió a una deta...

  1. Combustion Research Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Combustion Research Laboratory facilitates the development of new combustion systems or improves the operation of existing systems to meet the Army's mission for...

  2. Combustion chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.J. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    This research is concerned with the development and use of sensitivity analysis tools to probe the response of dependent variables to model input variables. Sensitivity analysis is important at all levels of combustion modeling. This group`s research continues to be focused on elucidating the interrelationship between features in the underlying potential energy surface (obtained from ab initio quantum chemistry calculations) and their responses in the quantum dynamics, e.g., reactive transition probabilities, cross sections, and thermal rate coefficients. The goals of this research are: (i) to provide feedback information to quantum chemists in their potential surface refinement efforts, and (ii) to gain a better understanding of how various regions in the potential influence the dynamics. These investigations are carried out with the methodology of quantum functional sensitivity analysis (QFSA).

  3. Oxygen-enhanced combustion

    CERN Document Server

    Baukal, Charles E

    2013-01-01

    Combustion technology has traditionally been dominated by air/fuel combustion. However, two developments have increased the significance of oxygen-enhanced combustion-new technologies that produce oxygen less expensively and the increased importance of environmental regulations. Advantages of oxygen-enhanced combustion include less pollutant emissions as well as increased energy efficiency and productivity. Oxygen-Enhanced Combustion, Second Edition compiles information about using oxygen to enhance industrial heating and melting processes. It integrates fundamental principles, applications, a

  4. Combustion 2000

    Energy Technology Data Exchange (ETDEWEB)

    A. Levasseur; S. Goodstine; J. Ruby; M. Nawaz; C. Senior; F. Robson; S. Lehman; W. Blecher; W. Fugard; A. Rao; A. Sarofim; P. Smith; D. Pershing; E. Eddings; M. Cremer; J. Hurley; G. Weber; M. Jones; M. Collings; D. Hajicek; A. Henderson; P. Klevan; D. Seery; B. Knight; R. Lessard; J. Sangiovanni; A. Dennis; C. Bird; W. Sutton; N. Bornstein; F. Cogswell; C. Randino; S. Gale; Mike Heap

    2001-06-30

    . To achieve these objectives requires a change from complete reliance of coal-fired systems on steam turbines (Rankine cycles) and moving forward to a combined cycle utilizing gas turbines (Brayton cycles) which offer the possibility of significantly greater efficiency. This is because gas turbine cycles operate at temperatures well beyond current steam cycles, allowing the working fluid (air) temperature to more closely approach that of the major energy source, the combustion of coal. In fact, a good figure of merit for a HIPPS design is just how much of the enthalpy from coal combustion is used by the gas turbine. The efficiency of a power cycle varies directly with the temperature of the working fluid and for contemporary gas turbines the optimal turbine inlet temperature is in the range of 2300-2500 F (1260-1371 C). These temperatures are beyond the working range of currently available alloys and are also in the range of the ash fusion temperature of most coals. These two sets of physical properties combine to produce the major engineering challenges for a HIPPS design. The UTRC team developed a design hierarchy to impose more rigor in our approach. Once the size of the plant had been determined by the choice of gas turbine and the matching steam turbine, the design process of the High Temperature Advanced Furnace (HITAF) moved ineluctably to a down-fired, slagging configuration. This design was based on two air heaters: one a high temperature slagging Radiative Air Heater (RAH) and a lower temperature, dry ash Convective Air Heater (CAH). The specific details of the air heaters are arrived at by an iterative sequence in the following order:-Starting from the overall Cycle requirements which set the limits for the combustion and heat transfer analysis-The available enthalpy determined the range of materials, ceramics or alloys, which could tolerate the temperatures-Structural Analysis of the designs proved to be the major limitation-Finally the commercialization

  5. Condicionamiento clasico electrodermico aversivo y apetitivo utilizando imagenes como estimulos

    National Research Council Canada - National Science Library

    Redondo, Jaime; Mendez, Amavia

    2011-01-01

    El principal objetivo de este estudio consistio en comprobar si era posible obtener condicionamiento clasico electrodermico, tanto aversivo como apetitivo, utilizando imagenes como estimulos condicionados (ECs...

  6. Combustion Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — For more than 30 years The Combustion Research Facility (CRF) has served as a national and international leader in combustion science and technology. The need for a...

  7. Combustion modeling in internal combustion engines

    Science.gov (United States)

    Zeleznik, F. J.

    1976-01-01

    The fundamental assumptions of the Blizard and Keck combustion model for internal combustion engines are examined and a generalization of that model is derived. The most significant feature of the model is that it permits the occurrence of unburned hydrocarbons in the thermodynamic-kinetic modeling of exhaust gases. The general formulas are evaluated in two specific cases that are likely to be significant in the applications of the model.

  8. Boiler using combustible fluid

    Science.gov (United States)

    Baumgartner, H.; Meier, J.G.

    1974-07-03

    A fluid fuel boiler is described comprising a combustion chamber, a cover on the combustion chamber having an opening for introducing a combustion-supporting gaseous fluid through said openings, means to impart rotation to the gaseous fluid about an axis of the combustion chamber, a burner for introducing a fluid fuel into the chamber mixed with the gaseous fluid for combustion thereof, the cover having a generally frustro-conical configuration diverging from the opening toward the interior of the chamber at an angle of between 15/sup 0/ and 55/sup 0/; means defining said combustion chamber having means defining a plurality of axial hot gas flow paths from a downstream portion of the combustion chamber to flow hot gases into an upstream portion of the combustion chamber, and means for diverting some of the hot gas flow along paths in a direction circumferentially of the combustion chamber, with the latter paths being immersed in the water flow path thereby to improve heat transfer and terminating in a gas outlet, the combustion chamber comprising at least one modular element, joined axially to the frustro-conical cover and coaxial therewith. The modular element comprises an inner ring and means of defining the circumferential, radial, and spiral flow paths of the hot gases.

  9. Axial design of nuclear fuel using path relinking; Diseno axial de combustible nuclear utilizando path relinking

    Energy Technology Data Exchange (ETDEWEB)

    Castillo, A.; Torres, M.; Ortiz, J. J.; Perusquia, R.; Hernandez, J. L.; Montes, J. L. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: jacm@nuclear.inin.mx

    2008-07-01

    In the present work the preliminary results were obtained with the zoctli system whose purpose is the axial design of assembly of nuclear fuel under certain considerations. For the mentioned design well-know cells were already used and that they have been proven in diverse cycles of operation in the nuclear power plant of Laguna Verde. The design contemplates fuels assemblies of 10x10 and with 2 water channels. The assembly was distributed in 6 axial zones according to its structure. In order to take to end the optimization is was used the well-known technique like Path relinking and to find the group of previous solutions required by this technique uses the technical Taboo search. In order to work with Path relinking, 5 trajectories was taken in to account from a set of 5 previous solutions generated with theTaboo search, the update of the group of solutions is carried out in dynamic form. In the case of the Taboo search it was used a list of variable size, it was implement an aspiration approach, it was used the vector of frequencies and due to the cost of the evaluation of the objective function, only it was review 5% of the vicinity. For the objective function was considered the limit thermal, the axial profile of power, the effective multiplication factor and the margin of having turned off in cold. In order to prove the design system, it was used a balance cycle with a value of reference of 0.9928 for the effective multiplication factor that is equivalent to a produced energy of 10896 MWd/TU at the end of operation to full power. The designed assemblies were placed both in one of lots different from fresh assemblies on which it counts the referred cycle. At the end one a comparison with the results obtained with other techniques and under similar conditions is made. The results obtained until the moment show an appropriate performance of the system. It is possible to indicate that a small inconvenient is the amount of consumed resources of calculation during the optimization process, due to the complexity of the calculations to obtain the parameters considered in the objective function. The system it was programed to use language FORTRAN 77 in a workstation alpha under UNIX platform. (Author)

  10. Lump wood combustion process

    Science.gov (United States)

    Kubesa, Petr; Horák, Jiří; Branc, Michal; Krpec, Kamil; Hopan, František; Koloničný, Jan; Ochodek, Tadeáš; Drastichová, Vendula; Martiník, Lubomír; Malcho, Milan

    2014-08-01

    The article deals with the combustion process for lump wood in low-power fireplaces (units to dozens of kW). Such a combustion process is cyclical in its nature, and what combustion facility users are most interested in is the frequency, at which fuel needs to be stoked to the fireplace. The paper defines the basic terms such as burnout curve and burning rate curve, which are closely related to the stocking frequency. The fuel burning rate is directly dependent on the immediate thermal power of the fireplace. This is also related to the temperature achieved in the fireplace, magnitude of flue gas losses and the ability to generate conditions favouring the full burnout of the fuel's combustible component, which, at once ensures the minimum production of combustible pollutants. Another part of the paper describes experiments conducted in traditional fireplaces with a grate, at which well-dried lump wood was combusted.

  11. Combustion Byproducts Recycling Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Paul Ziemkiewicz; Tamara Vandivort; Debra Pflughoeft-Hassett; Y. Paul Chugh; James Hower

    2008-08-31

    Ashlines: To promote and support the commercially viable and environmentally sound recycling of coal combustion byproducts for productive uses through scientific research, development, and field testing.

  12. Lectures on combustion theory

    Energy Technology Data Exchange (ETDEWEB)

    Burstein, S.Z.; Lax, P.D.; Sod, G.A. (eds.)

    1978-09-01

    Eleven lectures are presented on mathematical aspects of combustion: fluid dynamics, deflagrations and detonations, chemical kinetics, gas flows, combustion instability, flame spread above solids, spark ignition engines, burning rate of coal particles and hydrocarbon oxidation. Separate abstracts were prepared for three of the lectures. (DLC)

  13. Strobes: An Oscillatory Combustion

    NARCIS (Netherlands)

    Corbel, J.M.L.|info:eu-repo/dai/nl/341356034; van Lingen, J.N.J.|info:eu-repo/dai/nl/311441769; Zevenbergen, J.F.; Gijzeman, O.L.J.|info:eu-repo/dai/nl/073464708; Meijerink, A.|info:eu-repo/dai/nl/075044986

    2012-01-01

    Strobe compositions belong to the class of solid combustions. They are mixtures of powdered ingredients. When ignited, the combustion front evolves in an oscillatory fashion, and flashes of light are produced by intermittence. They have fascinated many scientists since their discovery at the

  14. Strobes: An oscillatory combustion

    NARCIS (Netherlands)

    Corbel, J.M.L.; Lingen, J.N.J. van; Zevenbergen, J.F.; Gijzeman, O.L.J.; Meijerink, A.

    2012-01-01

    Strobe compositions belong to the class of solid combustions. They are mixtures of powdered ingredients. When ignited, the combustion front evolves in an oscillatory fashion, and flashes of light are produced by intermittence. They have fascinated many scientists since their discovery at the

  15. Rocket Combustion Chamber Coating

    Science.gov (United States)

    Holmes, Richard R. (Inventor); McKechnie, Timothy N. (Inventor)

    2001-01-01

    A coating with the ability to protect (1) the inside wall (i.e., lining) of a rocket engine combustion chamber and (2) parts of other apparatuses that utilize or are exposed to combustive or high temperature environments. The novelty of this invention lies in the manner a protective coating is embedded into the lining.

  16. PDF Modeling of Turbulent Combustion

    National Research Council Canada - National Science Library

    Pope, Stephen B

    2006-01-01

    .... The PDF approach to turbulent combustion has the advantages of fully representing the turbulent fluctuations of species and temperature, and of allowing realistic combustion chemistry to be implemented...

  17. Fuels and Combustion

    KAUST Repository

    Johansson, Bengt

    2016-08-17

    This chapter discusses the combustion processes and the link to the fuel properties that are suitable for them. It describes the basic three concepts, including spark ignition (SI) and compression ignition (CI), and homogeneous charge compression ignition (HCCI). The fuel used in a CI engine is vastly different from that in an SI engine. In an SI engine, the fuel should sustain high pressure and temperature without autoignition. Apart from the dominating SI and CI engines, it is also possible to operate with a type of combustion: autoignition. With HCCI, the fuel and air are fully premixed before combustion as in the SI engine, but combustion is started by the increased pressure and temperature during the compression stroke. Apart from the three combustion processes, there are also a few combined or intermediate concepts, such as Spark-Assisted Compression Ignition (SACI). Those concepts are discussed in terms of the requirements of fuel properties.

  18. Sandia Combustion Research: Technical review

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    This report contains reports from research programs conducted at the Sandia Combustion Research Facility. Research is presented under the following topics: laser based diagnostics; combustion chemistry; reacting flow; combustion in engines and commercial burners; coal combustion; and industrial processing. Individual projects were processed separately for entry onto the DOE databases.

  19. Estudio de Algoritmos 2-Deslizantes Aplicados al Control de Pilas de Combustible

    Directory of Open Access Journals (Sweden)

    Cristian Kunusch

    2008-07-01

    Full Text Available Resumen: En este trabajo se hace un estudio comparativo de tres diferentes técnicas de control por modo deslizante de segundo orden, aplicadas al problema específico del control de respiración de una pila de combustible PEM. Los algoritmos diseñados se contrastan por simulación utilizando el modelo completo del sistema, poniendo particular énfasis en la respuesta transitoria y la robustez frente a perturbaciones. Palabras clave: Pilas de Combustible, Control no lineal, Modo Deslizante

  20. Combustion Technology Outreach

    Science.gov (United States)

    1995-01-01

    Lewis' High Speed Research (HSR) Propulsion Project Office initiated a targeted outreach effort to market combustion-related technologies developed at Lewis for the next generation of supersonic civil transport vehicles. These combustion-related innovations range from emissions measurement and reduction technologies, to diagnostics, spray technologies, NOx and SOx reduction of burners, noise reduction, sensors, and fuel-injection technologies. The Ohio Aerospace Institute and the Great Lakes Industrial Technology Center joined forces to assist Lewis' HSR Office in this outreach activity. From a database of thousands of nonaerospace firms considered likely to be interested in Lewis' combustion and emission-related technologies, the outreach team selected 41 companies to contact. The selected companies represent oil-gas refineries, vehicle/parts suppliers, and manufacturers of residential furnaces, power turbines, nonautomobile engines, and diesel internal combustion engines.

  1. Sandia Combustion Research Program

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, S.C.; Palmer, R.E.; Montana, C.A. (eds.)

    1988-01-01

    During the late 1970s, in response to a national energy crisis, Sandia proposed to the US Department of Energy (DOE) a new, ambitious program in combustion research. Shortly thereafter, the Combustion Research Facility (CRF) was established at Sandia's Livermore location. Designated a ''user facility,'' the charter of the CRF was to develop and maintain special-purpose resources to support a nationwide initiative-involving US inventories, industry, and national laboratories--to improve our understanding and control of combustion. This report includes descriptions several research projects which have been simulated by working groups and involve the on-site participation of industry scientists. DOE's Industry Technology Fellowship program, supported through the Office of Energy Research, has been instrumental in the success of some of these joint efforts. The remainder of this report presents results of calendar year 1988, separated thematically into eleven categories. Referred journal articles appearing in print during 1988 and selected other publications are included at the end of Section 11. Our traditional'' research activities--combustion chemistry, reacting flows, diagnostics, engine and coal combustion--have been supplemented by a new effort aimed at understanding combustion-related issues in the management of toxic and hazardous materials.

  2. Medición de la velocidad de propagación de llamas premezcladas de metano-aire y gas natural guajira aire utilizando el método del ángulo del cono

    OpenAIRE

    Pedro Nel Benjumea Hernández; Carlos Mario Higuita Bedoya; Camilo Andrés Cordoba Pérez

    2004-01-01

    En este trabajo se midió la velocidad de propagación de llamas premezcladas de metano aire y gas natural Guajira aire, utilizando el método del ángulo del cono con un quemador Bunsen cilíndrico. En el desarrollo de las pruebas se utilizaron mezclas gas combustible aire con un intervalo de concentración entre el 9% y el 11% por volumen de gas combustible, registrándose los máximos valores de velocidad de propagación de llama, Vu, en mezclas un poco más ricas que las correspo...

  3. Environmentally conscious coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Hickmott, D.D.; Brown, L.F.; Currier, R.P. [and others

    1997-08-01

    This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project was to evaluate the environmental impacts of home-scale coal combustion on the Navajo Reservation and develop strategies to reduce adverse health effects associated with home-scale coal combustion. Principal accomplishments of this project were: (1) determination of the metal and gaseous emissions of a representative stove on the Navajo Reservation; (2) recognition of cyclic gaseous emissions in combustion in home-scale combustors; (3) `back of the envelope` calculation that home-scale coal combustion may impact Navajo health; and (4) identification that improved coal stoves require the ability to burn diverse feedstocks (coal, wood, biomass). Ultimately the results of Navajo home-scale coal combustion studies will be extended to the Developing World, particularly China, where a significant number (> 150 million) of households continue to heat their homes with low-grade coal.

  4. Combustion and regulation; Combustion et reglementation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This conference was organized after the publication of the French by-law no 2010 relative to combustion installations and to the abatement of atmospheric pollution. Five topics were discussed during the conference: the new regulations, their content, innovations and modalities of application; the means of energy suppliers to face the new provisions and their schedule; the manufacturers proposals for existing installations and the new equipments; the administration control; and the impact of the new measures on exploitation and engineering. Twenty papers and 2 journal articles are reported in these proceedings. (J.S.)

  5. Combustible structural composites and methods of forming combustible structural composites

    Science.gov (United States)

    Daniels, Michael A.; Heaps, Ronald J.; Steffler, Eric D.; Swank, W. David

    2013-04-02

    Combustible structural composites and methods of forming same are disclosed. In an embodiment, a combustible structural composite includes combustible material comprising a fuel metal and a metal oxide. The fuel metal is present in the combustible material at a weight ratio from 1:9 to 1:1 of the fuel metal to the metal oxide. The fuel metal and the metal oxide are capable of exothermically reacting upon application of energy at or above a threshold value to support self-sustaining combustion of the combustible material within the combustible structural composite. Structural-reinforcing fibers are present in the composite at a weight ratio from 1:20 to 10:1 of the structural-reinforcing fibers to the combustible material. Other embodiments and aspects are disclosed.

  6. Internal combustion engine

    Science.gov (United States)

    Baker, Quentin A.; Mecredy, Henry E.; O'Neal, Glenn B.

    1991-01-01

    An improved engine is provided that more efficiently consumes difficult fuels such as coal slurries or powdered coal. The engine includes a precombustion chamber having a portion thereof formed by an ignition plug. The precombustion chamber is arranged so that when the piston is proximate the head, the precombustion chamber is sealed from the main cylinder or the main combustion chamber and when the piston is remote from the head, the precombustion chamber and main combustion chamber are in communication. The time for burning of fuel in the precombustion chamber can be regulated by the distance required to move the piston from the top dead center position to the position wherein the precombustion chamber and main combustion chamber are in communication.

  7. Fluidised Bed Combustion: A Novel Technology for the Combustion ...

    African Journals Online (AJOL)

    A firing technology, which is increasingly becoming popular for the combustion of fuels with difficult combustion properties, is fluidised bed combustion (FBC). In the current paper, the special features of FBC have been reviewed and their advantages as compared to conventional firing systems highlighted. This has been ...

  8. Alcohol combustion chemistry

    KAUST Repository

    Sarathy, Mani

    2014-10-01

    Alternative transportation fuels, preferably from renewable sources, include alcohols with up to five or even more carbon atoms. They are considered promising because they can be derived from biological matter via established and new processes. In addition, many of their physical-chemical properties are compatible with the requirements of modern engines, which make them attractive either as replacements for fossil fuels or as fuel additives. Indeed, alcohol fuels have been used since the early years of automobile production, particularly in Brazil, where ethanol has a long history of use as an automobile fuel. Recently, increasing attention has been paid to the use of non-petroleum-based fuels made from biological sources, including alcohols (predominantly ethanol), as important liquid biofuels. Today, the ethanol fuel that is offered in the market is mainly made from sugar cane or corn. Its production as a first-generation biofuel, especially in North America, has been associated with publicly discussed drawbacks, such as reduction in the food supply, need for fertilization, extensive water usage, and other ecological concerns. More environmentally friendly processes are being considered to produce alcohols from inedible plants or plant parts on wasteland. While biofuel production and its use (especially ethanol and biodiesel) in internal combustion engines have been the focus of several recent reviews, a dedicated overview and summary of research on alcohol combustion chemistry is still lacking. Besides ethanol, many linear and branched members of the alcohol family, from methanol to hexanols, have been studied, with a particular emphasis on butanols. These fuels and their combustion properties, including their ignition, flame propagation, and extinction characteristics, their pyrolysis and oxidation reactions, and their potential to produce pollutant emissions have been intensively investigated in dedicated experiments on the laboratory and the engine scale

  9. Scramjet Combustion Processes

    Science.gov (United States)

    2010-09-01

    Propulsion a vitesse elevee : Conception du moteur - integration et gestion thermique ) 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF...entrance to the combustion duct, where the production of the chemical radicals, which are a first stage in Scramjet Combustion Processes RTO-EN-AVT-185...314KM) Nosecone Eject (47SEC,73KM,M7.7) Orion Burnout (39SEC,56KM,M7.1) Orion Ignition (12SEC,9.4KM,M3.2) Terrier Ignition (0SEC,0KM,M0) Stage

  10. Radiative Augmented Combustion.

    Science.gov (United States)

    1985-08-12

    86-0085 In 00I to RADIATIVE AUGMENTED COMBUSTION MOSHE LAVID M.L. ENERGIA , INC. P.O. BOX 1468 1 PRINCETON, NEW JERSEY 08542 AUGUST 1985 *.. plo...Combustion conducted at M.L. ENERGIA . It is funded by the Air Force Office of Scientific Research under Contract No. F49620-83-C-0133, with Dr. J.M...reported. It covers the second year of the contract, from July 15, 1984 through July 14, 1985. The work was performed at ENERGIA , Princeton, New Jersey

  11. Studies in combustion dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Koszykowski, M.L. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    The goal of this program is to develop a fundamental understanding and a quantitative predictive capability in combustion modeling. A large part of the understanding of the chemistry of combustion processes comes from {open_quotes}chemical kinetic modeling.{close_quotes} However, successful modeling is not an isolated activity. It necessarily involves the integration of methods and results from several diverse disciplines and activities including theoretical chemistry, elementary reaction kinetics, fluid mechanics and computational science. Recently the authors have developed and utilized new tools for parallel processing to implement the first numerical model of a turbulent diffusion flame including a {open_quotes}full{close_quotes} chemical mechanism.

  12. Toxicology of Biodiesel Combustion products

    Science.gov (United States)

    1. Introduction The toxicology of combusted biodiesel is an emerging field. Much of the current knowledge about biological responses and health effects stems from studies of exposures to other fuel sources (typically petroleum diesel, gasoline, and wood) incompletely combusted. ...

  13. Fuel-Rich Catalytic Combustion

    Science.gov (United States)

    Brabbs, Theodore A.; Olson, Sandra L.

    1987-01-01

    Two-stage combustion system reduces particulate emissions. Program on catalytic oxidation of iso-octane demonstrates feasibility of two-stage combustion system for reducing particulate emissions. With fuel-rich (fuel/air equivalence ratios of 4.8 to 7.8) catalytic-combustion preburner as first stage, combustion process free of soot at reactor-outlet temperatures of 1,200 K or less.

  14. Coal combustion research

    Energy Technology Data Exchange (ETDEWEB)

    Daw, C.S.

    1996-06-01

    This section describes research and development related to coal combustion being performed for the Fossil Energy Program under the direction of the Morgantown Energy Technology Center. The key activity involves the application of chaos theory for the diagnosis and control of fossil energy processes.

  15. Nonlinear Combustion Instability Prediction

    Science.gov (United States)

    Flandro, Gary

    2010-01-01

    The liquid rocket engine stability prediction software (LCI) predicts combustion stability of systems using LOX-LH2 propellants. Both longitudinal and transverse mode stability characteristics are calculated. This software has the unique feature of being able to predict system limit amplitude.

  16. Supersonic Combustion Ramjet Research

    Science.gov (United States)

    2012-08-01

    engine). As noted above in USAF scramjet flight scenarios , high vehicle heat loads will ensure that the fuel (initially a liquid hydrocarbon such as a... cinema stereoscopic PIV system for the measurement of micro- and meso-scale turbulent premixed flame dynamics,” Paper B13, 5th US Combustion

  17. Sulfur Chemistry in Combustion I

    DEFF Research Database (Denmark)

    Johnsson, Jan Erik; Glarborg, Peter

    2000-01-01

    Most fossil fuels contain sulphur and also biofuels and household waste have a sulphur content. As a consequence sulphur species will often be present in combustion processes. In this paper the fate and influence of fuel sulphur species in combustion will be treated. First a description...... of the sulphur compounds in fossil fuels and the possibilities to remove them will be given. Then the combustion of sulphur species and their influence on the combustion chemistry and especially on the CO oxidation and the NOx formation will be described. Finally the in-situ removal of sulphur in the combustion...

  18. Low emission internal combustion engine

    Science.gov (United States)

    Karaba, Albert M.

    1979-01-01

    A low emission, internal combustion compression ignition engine having a cylinder, a piston movable in the cylinder and a pre-combustion chamber communicating with the cylinder near the top thereof and in which low emissions of NO.sub.x are achieved by constructing the pre-combustion chamber to have a volume of between 70% and 85% of the combined pre-chamber and main combustion chamber volume when the piston is at top dead center and by variably controlling the initiation of fuel injection into the pre-combustion chamber.

  19. Aerosols from biomass combustion

    Energy Technology Data Exchange (ETDEWEB)

    Nussbaumer, T.

    2001-07-01

    This report is the proceedings of a seminar on biomass combustion and aerosol production organised jointly by the International Energy Agency's (IEA) Task 32 on bio energy and the Swiss Federal Office of Energy (SFOE). This collection of 16 papers discusses the production of aerosols and fine particles by the burning of biomass and their effects. Expert knowledge on the environmental impact of aerosols, formation mechanisms, measurement technologies, methods of analysis and measures to be taken to reduce such emissions is presented. The seminar, visited by 50 participants from 11 countries, shows, according to the authors, that the reduction of aerosol emissions resulting from biomass combustion will remain a challenge for the future.

  20. Fluid-bed combustion

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, G.; Schoebotham, N.

    1981-02-01

    In Energy Equipment Company's two-stage fluidized bed system, partial combustion in a fluidized bed is followed by burn-off of the generated gases above the bed. The system can be retrofitted to existing boilers, and can burn small, high ash coal efficiently. It has advantages when used as a hot gas generator for process drying. Tests on a boiler at a Cadbury Schweppes plant are reported.

  1. Premixed Supersonic Combustion (Rev)

    Science.gov (United States)

    2015-02-20

    lean and low temperature flameout points). Figure 11. Chemiluminescence image (0.6 ms capture) at global φ = 0.41 (cavity-side = 0.27...mixing can still be rate-controlling if the flow temperature is high or if a flame holder is present and there is an adequate source of combustion... temperature associated with kinetic energy and ΔTc is the change in temperature associated with the chemistry [3]. If the rise in temperature

  2. Theory of Combustion Noise

    Science.gov (United States)

    1973-07-01

    The overall sound generation processes have been classi- fied in terms of the sound due to an isolated turbulent flame and that due to the...of the fluid mechanics of the reacting gas. The overall sound generation processes have been classified in terms of the sound due to an isolated ...steady intercoupling between various aerothermochemical modes excited in the combustion zone. To be specific, the non-steady exo- thermic and

  3. Combustion science and engineering

    CERN Document Server

    Annamalai, Kalyan

    2006-01-01

    Introduction and Review of Thermodynamics Introduction Combustion Terminology Matter and Its Properties Microscopic Overview of Thermodynamics Conservation of Mass and Energy and the First Law of Thermodynamics The Second Law of Thermodynamics Summary Stoichiometry and Thermochemistry of Reacting Systems Introduction Overall Reactions Gas Analyses Global Conservation Equations for Reacting Systems Thermochemistry Summary Appendix Reaction Direction and Equilibrium Introduction Reaction Direction and Chemical Equilibrium Chemical Equilibrium Relations Vant Hoff Equation Adi

  4. Combustion Characteristics of Sprays

    Science.gov (United States)

    1989-08-01

    regarded by implication or otherwise, or in any way licensing the holder or any other person or corporation, or conveying any rights or permission to...00 _’N 1. TI TLE inctuat Security CZaaafication5 Combustion Characteristics of Sprays 12. PERSONAL AUTHOR(S) Sohrab, Siavash H. 13& TYPE OF REPORT...to ?!HF of rich butane/air 3unsen flames. .lso, the rotacion speed and :he oerodic temDeracure fluc:uations of rotacfng ?HF are examined. :’!naily

  5. Strobes: an oscillatory combustion.

    Science.gov (United States)

    Corbel, Justine M L; Lingen, Joost N J; Zevenbergen, John F; Gijzeman, Onno L J; Meijerink, Andries

    2012-04-26

    Strobe compositions belong to the class of solid combustions. They are mixtures of powdered ingredients. When ignited, the combustion front evolves in an oscillatory fashion, and flashes of light are produced by intermittence. They have fascinated many scientists since their discovery at the beginning of the 20th century. However, the chemical and physical processes involved in this curious oscillatory combustion remain unknown. Several theories have been proposed: One claims that two different reactions occur: one during the slow dark phase and another during the fast flash phase. The alternation between the phases is ascribed to heat variations. Other theories suggest that the formation of intermediate species during the dark phase and the change of phase are caused by variations in their concentration. A ternary strobe composition with ammonium perchlorate, magnalium, and barium sulfate is analyzed. The role of barium sulfate is studied by replacing it by other metal sulfates that have different physical properties (melting points), and the burning of the compositions is recorded with a high-speed camera and a spectrometer coupled with a charge-coupled device (CCD) camera. Experimental results show noticeable differences in the physical and chemical processes involved in the strobe reactions.

  6. Internal combustion piston engines

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.L.

    1977-07-01

    Current worldwide production of internal combustion piston engines includes many diversified types of designs and a very broad range of sizes. Engine sizes range from a few horsepower in small mobile units to over 40,000 brake horsepower in large stationary and marine units. The key characteristics of internal combustion piston engines considered appropriate for use as prime movers in Integrated Community Energy Systems (ICES) are evaluated. The categories of engines considered include spark-ignition gas engines, compression-ignition oil (diesel) engines, and dual-fuel engines. The engines are evaluated with respect to full-load and part-load performance characteristics, reliability, environmental concerns, estimated 1976 cost data, and current and future status of development. The largest internal combustion piston engines manufactured in the United States range up to 13,540 rated brake horsepower. Future development efforts are anticipated to result in a 20 to 25% increase in brake horsepower without increase in or loss of weight, economy, reliability, or life expectancy, predicated on a simple extension of current development trends.

  7. Issues in waste combustion

    Energy Technology Data Exchange (ETDEWEB)

    Gustavsson, Lennart; Robertson, Kerstin; Tullin, Claes [Swedish National Testing and Research Inst., Boraas (Sweden); Sundquist, Lena; Wrangensten, Lars [AaF-Energikonsult AB, Stockholm (Sweden); Blom, Elisabet [AaF-Processdesign AB, Stockholm (Sweden)

    2003-05-01

    The main purpose of this review is to provide an overview of the state-of-the-art on research and development issues related to waste combustion with relevance for Swedish conditions. The review focuses on co-combustion in grate and fluidised bed furnaces. It is primarily literature searches in relevant databases of scientific publications with to material published after 1995. As a complement, findings published in different report series, have also been included. Since the area covered by this report is very wide, we do not claim to cover the issues included completely and it has not been possitile to evaluate the referred studies in depth. Basic knowledge about combustion issues is not included since such information can be found elsewhere in the literature. Rather, this review should be viewed as an overview of research and development in the waste-to-energy area and as such we hope that it will inspire scientists and others to further work in relevant areas.

  8. Spray combustion stability

    Science.gov (United States)

    Liang, Pak-Yan; Jeng, S. M.; Litchford, Ronald

    1995-01-01

    The central purpose of this project is the improvement of liquid-fueled rocket motor design technology in order to assist the establishment of economical commercial access to space through the development of engines with enhanced performance and reliability. Specific research effort in the project is focused on spray physics and associated combustion instability phenomena. Results garnered from this work will contribute to the development of new computational tools for design of stable liquid propellant rocket engines. The specific objectives of the research effort include identifying and evaluating physical submodels which pertain to spray combustion stability with the idea of enhancing or refining existing submodels with a more comprehensive approach. In particular, any refinements to the spray combustion physical submodels which are achieved during the project will be channeled back to Rocketdyne for incorporation in their ARICC liquid rocket combustor code as second generation improvements. Also, as the ARICC code forms the basis or future CFD development, some effort is devoted to an evaluation of the code's capability for modeling oscillating pressure waves within the combustor.

  9. The Diesel Combustion Collaboratory: Combustion Researchers Collaborating over the Internet

    Energy Technology Data Exchange (ETDEWEB)

    C. M. Pancerella; L. A. Rahn; C. Yang

    2000-02-01

    The Diesel Combustion Collaborator (DCC) is a pilot project to develop and deploy collaborative technologies to combustion researchers distributed throughout the DOE national laboratories, academia, and industry. The result is a problem-solving environment for combustion research. Researchers collaborate over the Internet using DCC tools, which include: a distributed execution management system for running combustion models on widely distributed computers, including supercomputers; web-accessible data archiving capabilities for sharing graphical experimental or modeling data; electronic notebooks and shared workspaces for facilitating collaboration; visualization of combustion data; and video-conferencing and data-conferencing among researchers at remote sites. Security is a key aspect of the collaborative tools. In many cases, the authors have integrated these tools to allow data, including large combustion data sets, to flow seamlessly, for example, from modeling tools to data archives. In this paper the authors describe the work of a larger collaborative effort to design, implement and deploy the DCC.

  10. Internal combustion engine using premixed combustion of stratified charges

    Science.gov (United States)

    Marriott, Craig D [Rochester Hills, MI; Reitz, Rolf D [Madison, WI

    2003-12-30

    During a combustion cycle, a first stoichiometrically lean fuel charge is injected well prior to top dead center, preferably during the intake stroke. This first fuel charge is substantially mixed with the combustion chamber air during subsequent motion of the piston towards top dead center. A subsequent fuel charge is then injected prior to top dead center to create a stratified, locally richer mixture (but still leaner than stoichiometric) within the combustion chamber. The locally rich region within the combustion chamber has sufficient fuel density to autoignite, and its self-ignition serves to activate ignition for the lean mixture existing within the remainder of the combustion chamber. Because the mixture within the combustion chamber is overall premixed and relatively lean, NO.sub.x and soot production are significantly diminished.

  11. Development of flameless combustion; Desarrollo de la combustion sin flama

    Energy Technology Data Exchange (ETDEWEB)

    Flores Sauceda, M. Leonardo; Cervantes de Gortari, Jaime Gonzalo [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)]. E-mail: 8344afc@prodigy.net.mx; jgonzalo@servidor.unam.mx

    2010-11-15

    The paper intends contribute to global warming mitigation joint effort that develops technologies to capture the CO{sub 2} produced by fossil fuels combustion and to reduce emission of other greenhouse gases like the NO{sub x}. After reviewing existing combustion bibliography is pointed out that (a) touches only partial aspects of the collective system composed by Combustion-Heat transfer process-Environment, whose interactions are our primary interest and (b) most specialists think there is not yet a clearly winning technology for CO{sub 2} capture and storage. In this paper the study of combustion is focused as integrated in the aforementioned collective system where application of flameless combustion, using oxidant preheated in heat regenerators and fluent gas recirculation into combustion chamber plus appropriated heat and mass balances, simultaneously results in energy saving and environmental impact reduction. [Spanish] El trabajo pretende contribuir al esfuerzo conjunto de mitigacion del calentamiento global que aporta tecnologias para capturar el CO{sub 2} producido por la combustion de combustibles fosiles y para disminuir la emision de otros gases invernadero como NOx. De revision bibliografica sobre combustion se concluye que (a) trata aspectos parciales del sistema compuesto por combustion-proceso de trasferencia de calor-ambiente, cuyas interacciones son nuestro principal interes (b) la mayoria de especialistas considera no hay todavia una tecnologia claramente superior a las demas para captura y almacenaje de CO{sub 2}. Se estudia la combustion como parte integrante del mencionado sistema conjunto, donde la aplicacion de combustion sin flama, empleando oxidante precalentado mediante regeneradores de calor y recirculacion de gases efluentes ademas de los balances de masa y energia adecuados, permite tener simultaneamente ahorros energeticos e impacto ambiental reducido.

  12. Pulsating combustion - Combustion characteristics and reduction of emissions

    Energy Technology Data Exchange (ETDEWEB)

    Lindholm, Annika

    1999-11-01

    In the search for high efficiency combustion systems pulsating combustion has been identified as one of the technologies that potentially can meet the objectives of clean combustion and good fuel economy. Pulsating combustion offers low emissions of pollutants, high heat transfer and efficient combustion. Although it is an old technology, the interest in pulsating combustion has been renewed in recent years, due to its unique features. Various applications of pulsating combustion can be found, mainly as drying and heating devices, of which the latter also have had commercial success. It is, however, in the design process of a pulse combustor, difficult to predict the operating frequency, the heat release etc., due to the lack of a well founded theory of the phenomenon. Research concerning control over the combustion process is essential for developing high efficiency pulse combustors with low emissions. Natural gas fired Helmholtz type pulse combustors have been the experimental objects of this study. In order to investigate the interaction between the fluid dynamics and the chemistry in pulse combustors, laser based measuring techniques as well as other conventional measuring techniques have been used. The experimental results shows the possibilities to control the combustion characteristics of pulsating combustion. It is shown that the time scales in the large vortices created at the inlet to the combustion chamber are very important for the operation of the pulse combustor. By increasing/decreasing the time scale for the large scale mixing the timing of the heat release is changed and the operating characteristics of the pulse combustor changes. Three different means for NO{sub x} reduction in Helmholtz type pulse combustors have been investigated. These include exhaust gas recirculation, alteration of air/fuel ratio and changed inlet geometry in the combustion chamber. All used methods achieved less than 10 ppm NO{sub x} emitted (referred to stoichiometric

  13. Purificação de acido clavulanico utilizando zeolitas.

    OpenAIRE

    Marcus Bruno Soares Forte

    2008-01-01

    Resumo: O presente trabalho teve como objetivo principal a separação e purificação de acido clavulanico a partir de caldo fermentado utilizando zeolitas. Foram utilizadas zeolita natural (ZN) e sintetica faujasita (13X), ambas modificadas por troca ionica com diferentes cations de compensação (Na+1, K+1, Ca+2, Ba+2, Mg+2, Sr+2). Atraves de estudos cineticos de adsorcao de AC, usando as diferentes zeolitas nas respectivas formas cationicas, selecionou-se a zeolita 13X-Na como a mais promissora...

  14. Combustion from basics to applications

    CERN Document Server

    Lackner, Maximilian; Winter, Franz

    2013-01-01

    Combustion, the process of burning, is defined as a chemical reaction between a combustible reactant (the fuel) and an oxidizing agent (such as air) in order to produce heat and in most cases light while new chemical species (e.g., flue gas components) are formed. This book covers a gap on the market by providing a concise introduction to combustion. Most of the other books currently available are targeted towards the experienced users and contain too many details and/or contain knowledge at a fairly high level. This book provides a brief and clear overview of the combustion basics, suitable f

  15. The modes of gaseous combustion

    CERN Document Server

    Rubtsov, Nickolai M

    2016-01-01

    This book provides an analysis of contemporary problems in combustion science, namely flame propagation, detonation and heterophaseous combustion based on the works of the author. The current problems in the area of gas combustion, as well as the methods allowing to calculate and estimate limiting conditions of ignition, and flame propagation on the basis of experimental results are considered. The book focuses on the virtually inaccessible works of Russian authors and will be useful for experienced students and qualified scientists in the area of experimental studies of combustion processes.

  16. Active Combustion Control Valve Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Over the past decade, research into active combustion control has yielded impressive results in suppressing thermoacoustic instabilities and widening the operational...

  17. Light Duty Efficient, Clean Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Stanton, Donald W. [Cummins Inc., Columbus, IN (United States)

    2011-06-03

    Cummins has successfully completed the Light Duty Efficient Clean Combustion (LDECC) cooperative program with DoE. This program was established in 2007 in support of the Department of Energy’s Vehicles Technologies Advanced Combustion and Emissions Control initiative to remove critical barriers to the commercialization of advanced, high efficiency, emissions compliant internal combustion (IC) engines for light duty vehicles. Work in this area expanded the fundamental knowledge of engine combustion to new regimes and advanced the knowledge of fuel requirements for these diesel engines to realize their full potential. All of our objectives were met with fuel efficiency improvement targets exceeded.

  18. Mathematical Modeling in Combustion Science

    CERN Document Server

    Takeno, Tadao

    1988-01-01

    An important new area of current research in combustion science is reviewed in the contributions to this volume. The complicated phenomena of combustion, such as chemical reactions, heat and mass transfer, and gaseous flows, have so far been studied predominantly by experiment and by phenomenological approaches. But asymptotic analysis and other recent developments are rapidly changing this situation. The contributions in this volume are devoted to mathematical modeling in three areas: high Mach number combustion, complex chemistry and physics, and flame modeling in small scale turbulent flow combustion.

  19. Microgravity Smoldering Combustion Takes Flight

    Science.gov (United States)

    1996-01-01

    The Microgravity Smoldering Combustion (MSC) experiment lifted off aboard the Space Shuttle Endeavour in September 1995 on the STS-69 mission. This experiment is part of series of studies focused on the smolder characteristics of porous, combustible materials in a microgravity environment. Smoldering is a nonflaming form of combustion that takes place in the interior of combustible materials. Common examples of smoldering are nonflaming embers, charcoal briquettes, and cigarettes. The objective of the study is to provide a better understanding of the controlling mechanisms of smoldering, both in microgravity and Earth gravity. As with other forms of combustion, gravity affects the availability of air and the transport of heat, and therefore, the rate of combustion. Results of the microgravity experiments will be compared with identical experiments carried out in Earth's gravity. They also will be used to verify present theories of smoldering combustion and will provide new insights into the process of smoldering combustion, enhancing our fundamental understanding of this frequently encountered combustion process and guiding improvement in fire safety practices.

  20. Volumetric Combustion Diagnostics

    Science.gov (United States)

    2017-01-03

    i.e., the central plane of the burner and the plane where the PLIF measurement was taken) was extracted and plotted in Fig. 7b. Fig. 7c directly...Hsu, Particle Image Velocimetry in a Nonreacting and Reacting High-Speed Cavity, Journal of Propulsion and Power, 30(3) (2014) 576-591. [7] Y.W...quantitative laser sensors to kinetics, propulsion and practical energy systems, Proceedings of the Combustion Institute, 33(1) (2011) 1-40. [13] A.W

  1. Alternate fuels; Combustibles alternos

    Energy Technology Data Exchange (ETDEWEB)

    Romero Paredes R, Hernando; Ambriz G, Juan Jose [Universidad Autonoma Metropolitana. Iztapalapa (Mexico)

    2003-07-01

    In the definition and description of alternate fuels we must center ourselves in those technological alternatives that allow to obtain compounds that differ from the traditional ones, in their forms to be obtained. In this article it is tried to give an overview of alternate fuels to the conventional derivatives of petroleum and that allow to have a clear idea on the tendencies of modern investigation and the technological developments that can be implemented in the short term. It is not pretended to include all the tendencies and developments of the present world, but those that can hit in a relatively short term, in accordance with agreed with the average life of conventional fuels. Nevertheless, most of the conversion principles are applicable to the spectrum of carbonaceous or cellulosic materials which are in nature, are cultivated or wastes of organic origin. Thus one will approach them in a successive way, the physical, chemical and biological conversions that can take place in a production process of an alternate fuel or the same direct use of the fuel such as burning the sweepings derived from the forests. [Spanish] En la definicion y descripcion de combustibles alternos nos debemos centrar en aquellas alternativas tecnologicas que permitan obtener compuestos que difieren de los tradicionales, al menos en sus formas de ser obtenidos. En este articulo se pretende dar un panorama de los combustibles alternos a los convencionales derivados del petroleo y que permita tener una idea clara sobre las tendencias de la investigacion moderna y los desarrollos tecnologicos que puedan ser implementados en el corto plazo. No se pretende abarcar todas las tendencias y desarrollos del mundo actual, sino aquellas que pueden impactar en un plazo relativamente corto, acordes con la vida media de los combustibles convencionales. Sin embargo, la mayor parte de los principios de conversion son aplicables al espectro de materiales carbonaceos o celulosicos los cuales se

  2. Combustion Stratification for Naphtha from CI Combustion to PPC

    KAUST Repository

    Vallinayagam, R.

    2017-03-28

    This study demonstrates the combustion stratification from conventional compression ignition (CI) combustion to partially premixed combustion (PPC). Experiments are performed in an optical CI engine at a speed of 1200 rpm for diesel and naphtha (RON = 46). The motored pressure at TDC is maintained at 35 bar and fuelMEP is kept constant at 5.1 bar to account for the difference in fuel properties between naphtha and diesel. Single injection strategy is employed and the fuel is injected at a pressure of 800 bar. Photron FASTCAM SA4 that captures in-cylinder combustion at the rate of 10000 frames per second is employed. The captured high speed video is processed to study the combustion homogeneity based on an algorithm reported in previous studies. Starting from late fuel injection timings, combustion stratification is investigated by advancing the fuel injection timings. For late start of injection (SOI), a direct link between SOI and combustion phasing is noticed. At early SOI, combustion phasing depends on both intake air temperature and SOI. In order to match the combustion phasing (CA50) of diesel, the intake air temperature is increased to 90°C for naphtha. The combustion stratification from CI to PPC is also investigated for various level of dilution by displacing oxygen with nitrogen in the intake. The start of combustion (SOC) was delayed with the increase in dilution and to compensate for this, the intake air temperature is increased. The mixture homogeneity is enhanced for higher dilution due to longer ignition delay. The results show that high speed image is initially blue and then turned yellow, indicating soot formation and oxidation. The luminosity of combustion images decreases with early SOI and increased dilution. The images are processed to generate the level of stratification based on the image intensity. The level of stratification is same for diesel and naphtha at various SOI. When O concentration in the intake is decreased to 17.7% and 14

  3. Some Factors Affecting Combustion in an Internal-Combustion Engine

    Science.gov (United States)

    Rothrock, A M; Cohn, Mildred

    1936-01-01

    An investigation of the combustion of gasoline, safety, and diesel fuels was made in the NACA combustion apparatus under conditions of temperature that permitted ignition by spark with direct fuel injection, in spite of the compression ratio of 12.7 employed. The influence of such variables as injection advance angle, jacket temperature, engine speed, and spark position was studied. The most pronounced effect was that an increase in the injection advance angle (beyond a certain minimum value) caused a decrease in the extent and rate of combustion. In almost all cases combustion improved with increased temperature. The results show that at low air temperatures the rates of combustion vary with the volatility of the fuel, but that at high temperatures this relationship does not exist and the rates depend to a greater extent on the chemical nature of the fuel.

  4. AIR EMISSIONS FROM SCRAP TIRE COMBUSTION

    Science.gov (United States)

    The report discusses air emissions from two types of scrap tire combustion: uncontrolled and controlled. Uncontrolled sources are open tire fires, which produce many unhealthful products of incomplete combustion and release them directly into the atmosphere. Controlled combustion...

  5. Plasma igniter for internal-combustion engines

    Science.gov (United States)

    Breshears, R. R.; Fitzgerald, D. J.

    1978-01-01

    Hot ionized gas (plasma) ignites air/fuel mixture in internal combustion engines more effectively than spark. Electromagnetic forces propel plasma into combustion zone. Combustion rate is not limited by flame-front speed.

  6. Combustion of Methane Hydrate

    Science.gov (United States)

    Roshandell, Melika

    A significant methane storehouse is in the form of methane hydrates on the sea floor and in the arctic permafrost. Methane hydrates are ice-like structures composed of water cages housing a guest methane molecule. This caged methane represents a resource of energy and a potential source of strong greenhouse gas. Most research related to methane hydrates has been focused on their formation and dissociation because they can form solid plugs that complicate transport of oil and gas in pipelines. This dissertation explores the direct burning of these methane hydrates where heat from the combustion process dissociates the hydrate into water and methane, and the released methane fuels the methane/air diffusion flame heat source. In contrast to the pipeline applications, very little research has been done on the combustion and burning characteristics of methane hydrates. This is the first dissertation on this subject. In this study, energy release and combustion characteristics of methane hydrates were investigated both theoretically and experimentally. The experimental study involved collaboration with another research group, particularly in the creation of methane hydrate samples. The experiments were difficult because hydrates form at high pressure within a narrow temperature range. The process can be slow and the resulting hydrate can have somewhat variable properties (e.g., extent of clathration, shape, compactness). The experimental study examined broad characteristics of hydrate combustion, including flame appearance, burning time, conditions leading to flame extinguishment, the amount of hydrate water melted versus evaporated, and flame temperature. These properties were observed for samples of different physical size. Hydrate formation is a very slow process with pure water and methane. The addition of small amounts of surfactant increased substantially the hydrate formation rate. The effects of surfactant on burning characteristics were also studied. One finding

  7. Manifold methods for methane combustion

    Energy Technology Data Exchange (ETDEWEB)

    Yang, B.; Pope, S.B. [Cornell Univ., Ithaca, NY (United States)

    1995-10-01

    Great progresses have been made in combustion research, especially, the computation of laminar flames and the probability density function (PDF) method in turbulent combustion. For one-dimensional laminar flames, by considering the transport mechanism, the detailed chemical kinetic mechanism and the interactions between these two basic processes, today it is a routine matter to calculate flame velocities, extinction, ignition, temperature, and species distributions from the governing equations. Results are in good agreement with those obtained for experiments. However, for turbulent combustion, because of the complexities of turbulent flow, chemical reactions, and the interaction between them, in the foreseeable future, it is impossible to calculate the combustion flow field by directly integrating the basic governing equations. So averaging and modeling are necessary in turbulent combustion studies. Averaging, on one hand, simplifies turbulent combustion calculations, on the other hand, it introduces the infamous closure problems, especially the closure problem with chemical reaction terms. Since in PDF calculations of turbulent combustion, the averages of the chemical reaction terms can be calculated, PDF methods overcome the closure problem with the reaction terms. It has been shown that the PDF method is a most promising method to calculate turbulent combustion. PDF methods have been successfully employed to calculate laboratory turbulent flames: they can predict phenomena such as super equilibrium radical levels, and local extinction. Because of these advantages, PDF methods are becoming used increasingly in industry combustor codes.

  8. Liquid propellant rocket combustion instability

    Science.gov (United States)

    Harrje, D. T.

    1972-01-01

    The solution of problems of combustion instability for more effective communication between the various workers in this field is considered. The extent of combustion instability problems in liquid propellant rocket engines and recommendations for their solution are discussed. The most significant developments, both theoretical and experimental, are presented, with emphasis on fundamental principles and relationships between alternative approaches.

  9. Combustion & Laser Diagnostics Research Complex (CLDRC)

    Data.gov (United States)

    Federal Laboratory Consortium — Description: The Combustion and Laser Diagnostics Research Complex (CLRDC) supports the experimental and computational study of fundamental combustion phenomena to...

  10. Sistema auxiliar de movimiento de varillas para inspección de combustible nuclear

    OpenAIRE

    Rodríguez Roncero, Jorge

    2017-01-01

    En el presente proyecto, se quiere desarrollar un sistema cuyo fin es el de desplazar una varilla con combustible nuclear para su inspección, utilizando para su desplazamiento motores paso a paso y sensores inductivos. El proyecto se divide en dos partes. Una primera parte de diseño estructural, en la que se buscarán los materiales más adecuados para el montaje de la estructura por la que se desplazará la varilla. Una segunda parte de programación, en la que se realizará el código para conseg...

  11. Curvas de desempenho motor de um trator agrícola utilizando diferentes proporções de biodiesel de soja

    Directory of Open Access Journals (Sweden)

    Vanderson Rabelo de Paula

    2015-07-01

    Full Text Available A crise energética, associada ao aumento da demanda por combustíveis e à crescente preocupação com o meio ambiente, tem levado à busca por fontes alternativas de energia. Além disso, a entrada de novos equipamentos e máquinas agrícolas altamente competitivos, em termos de custo, vem despertando o interesse dos agricultores. No entanto, tais equipamentos, pela sua recente inserção no mercado, ainda não apresentam parâmetros que os remetam à confiabilidade. Nesse contexto, este estudo visou ao ensaio dinamométrico de tomada de potência (TDP de um trator agrícola da marca Green Horse, modelo 204, para obtenção de suas curvas de desempenho, utilizando como combustível misturas de óleo diesel e biodiesel de soja, nas proporções B2, B5, B20 e B100. Os resultados mostraram que o trator apresentou desempenho motor compatível com outros modelos de mesma potência utilizados no país, apresentando o melhor desempenho com o uso do combustível B5.

  12. Spying on spontaneous combustion

    Energy Technology Data Exchange (ETDEWEB)

    1994-11-01

    The British Coal Technical Services and Research Executive (TSRE) has carried out a project to investigate potential applications of fibre optic based distributed temperature sensing (DTS) technology within a mining environment. The objective was to determine whether DTS could identify and locate spontaneous combustion earlier than conventional systems. The trials took place in a British mine from April to September 1992 and from August to November 1993 using a commercially available system from York Sensors Ltd. Results indicate that DTS is capable of very sensitive temperature monitoring, revealing sub-degree thermal trends resulting from various activities and local heatings. DTS has several prospective mining applications, e.g. monitoring known hot spots, investigating ventilation and heat flow through mine workings. The trials show that the system can be installed, calibrated, operated and maintained by relatively inexperienced personnel. 1 photo.

  13. Forced cocurrent smoldering combustion

    Science.gov (United States)

    Dosanjh, Sudip S.; Pagni, Patrick J.; Fernandez-Pello, A. Carlos

    1987-01-01

    An analytical model of cocurrent smoldering combustion through a very porous solid fuel is developed. Smoldering is initiated at the top of a long radially insulated uniform fuel cylinder, so that the smolder wave propagates downward, opposing an upward-forced flow of oxidizer, with the solid fuel and the gaseous oxidizer entering the reaction zone from the same direction (hence, cocurrent). Radiative heat transfer was incorporated using a diffusion approximation, and smoldering was modeled using a one-step reaction mechanism. The results indicate that, for a given fuel, the final temperature depends only on the initial oxygen mass flux, increasing logarithmically with the mass flux. The smolder velocity is linearly dependent on the initial oxygen mass flux, and, at a fixed value of the flux, increases with initial oxygen mass fraction. The mathematical relationship determining the conditions for steady smolder propagation is presented.

  14. Planeamento de uma estrada utilizando CCS Candy - Caso de estudo

    OpenAIRE

    Oliveira, Sara Maria de

    2013-01-01

    O tema desta dissertação foi escolhido tendo em consideração a crescente necessidade de planeamento de empreitadas de construção de estradas, sendo um dos objetivos desta dissertação o de oferecer uma visão global do processo de planeamento da construção de uma estrada, focado apenas no fator tempo, recorrendo a ferramentas informáticas e utilizando um caso de estudo de uma estrada real e já construída. Inicialmente, faz-se uma breve descrição dos métodos de planeamento mais aplicados em p...

  15. Extração de rodovias utilizando SNAKES

    OpenAIRE

    Oliveira, Rafael Montanhini Soares de [UNESP

    2003-01-01

    A obtenção de informações a partir da extração de feições em fotos aéreas e imagens de satélite é um dos principais objetivos da nova tecnologia de automação em Fotogrametria Digital. Este trabalho propõe a extração de rodovias, e a conexão de segmentos de rodovias extraidos por outros extratores de feições, utilizando modelos de contorno ativo ou snakes. Snakes foi introduzido há quase duas décadas e consiste em uma curva representada parametricamente e controlada por injunções fotométricas ...

  16. Filtration combustion: Smoldering and SHS

    Science.gov (United States)

    Matkowsky, Bernard J.

    1995-01-01

    Smolder waves and SHS (self-propagating high-temperature synthesis) waves are both examples of combustion waves propagating in porous media. When delivery of reactants through the pores to the reaction site is an important aspect of the process, it is referred to as filtration combustion. The two types of filtration combustion have a similar mathematical formulation, describing the ignition, propagation and extinction of combustion waves in porous media. The goal in each case, however, is different. In smoldering the desired goal is to prevent propagation, whereas in SHS the goal is to insure propagation of the combustion wave, leading to the synthesis of desired products. In addition, the scales in the two areas of application may well differ. For example, smoldering generally occurs at a relatively low temperature and with a smaller propagation velocity than SHS filtration combustion waves. Nevertheless, the two areas of application have much in common, so that mechanisms learned about in one application can be used to advantage in the other. In this paper we discuss recent results in the areas of filtration combustion.

  17. Catalytic Combustion of Gasified Waste

    Energy Technology Data Exchange (ETDEWEB)

    Kusar, Henrik

    2003-09-01

    This thesis concerns catalytic combustion for gas turbine application using a low heating-value (LHV) gas, derived from gasified waste. The main research in catalytic combustion focuses on methane as fuel, but an increasing interest is directed towards catalytic combustion of LHV fuels. This thesis shows that it is possible to catalytically combust a LHV gas and to oxidize fuel-bound nitrogen (NH{sub 3}) directly into N{sub 2} without forming NO{sub x} The first part of the thesis gives a background to the system. It defines waste, shortly describes gasification and more thoroughly catalytic combustion. The second part of the present thesis, paper I, concerns the development and testing of potential catalysts for catalytic combustion of LHV gases. The objective of this work was to investigate the possibility to use a stable metal oxide instead of noble metals as ignition catalyst and at the same time reduce the formation of NO{sub x} In paper II pilot-scale tests were carried out to prove the potential of catalytic combustion using real gasified waste and to compare with the results obtained in laboratory scale using a synthetic gas simulating gasified waste. In paper III, selective catalytic oxidation for decreasing the NO{sub x} formation from fuel-bound nitrogen was examined using two different approaches: fuel-lean and fuel-rich conditions. Finally, the last part of the thesis deals with deactivation of catalysts. The various deactivation processes which may affect high-temperature catalytic combustion are reviewed in paper IV. In paper V the poisoning effect of low amounts of sulfur was studied; various metal oxides as well as supported palladium and platinum catalysts were used as catalysts for combustion of a synthetic gas. In conclusion, with the results obtained in this thesis it would be possible to compose a working catalytic system for gas turbine application using a LHV gas.

  18. On Lean Turbulent Combustion Modeling

    Directory of Open Access Journals (Sweden)

    Constantin LEVENTIU

    2014-06-01

    Full Text Available This paper investigates a lean methane-air flame with different chemical reaction mechanisms, for laminar and turbulent combustion, approached as one and bi-dimensional problem. The numerical results obtained with Cantera and Ansys Fluent software are compared with experimental data obtained at CORIA Institute, France. First, for laminar combustion, the burn temperature is very well approximated for all chemical mechanisms, however major differences appear in the evaluation of the flame front thickness. Next, the analysis of turbulence-combustion interaction shows that the numerical predictions are suficiently accurate for small and moderate turbulence intensity.

  19. Combustion of Solid Propellants (La Combustion des Propergols Solides)

    Science.gov (United States)

    1991-07-01

    poudres modificateurs balistiques, des noirs de A mouler de caract~ristiques volontairement carbone sont souvent incorpor~s car ils ont diffdrontes ce...de antilueurs (suppresseurs de la post noir de carbone eat souvent utilisd combustion). Ceux-ci, g~ndralement des sels industriellemont comae param...devient compressible at is vitesse de combustion Pour 6tablir un bilan sur le risque eat modifide. La figure 7 illustre cet d’appariticn d’instabilit~s

  20. Measures for a quality combustion (combustion chamber exit and downstream); Mesures pour une combustion de qualite (sortie de chambre de combustion et en aval)

    Energy Technology Data Exchange (ETDEWEB)

    Epinat, G. [APAVE Lyonnaise, 69 (France)

    1996-12-31

    After a review of the different pollutants related to the various types of stationary and mobile combustion processes (stoichiometric, reducing and oxidizing combustion), measures and analyses than may be used to ensure the quality and efficiency of combustion processes are reviewed: opacimeters, UV analyzers, etc. The regulation and control equipment for combustion systems are then listed, according to the generator capacity level

  1. Computational Modeling of Turbulent Spray Combustion

    NARCIS (Netherlands)

    Ma, L.

    2016-01-01

    The objective of the research presented in this thesis is development and validation of predictive models or modeling approaches of liquid fuel combustion (spray combustion) in hot-diluted environments, known as flameless combustion or MILD combustion. The goal is to combine good physical insight,

  2. Fifth International Microgravity Combustion Workshop

    Science.gov (United States)

    Sacksteder, Kurt (Compiler)

    1999-01-01

    This conference proceedings document is a compilation of 120 papers presented orally or as poster displays to the Fifth International Microgravity Combustion Workshop held in Cleveland, Ohio on May 18-20, 1999. The purpose of the workshop is to present and exchange research results from theoretical and experimental work in combustion science using the reduced-gravity environment as a research tool. The results are contributed by researchers funded by NASA throughout the United States at universities, industry and government research agencies, and by researchers from at least eight international partner countries that are also participating in the microgravity combustion science research discipline. These research results are intended for use by public and private sector organizations for academic purposes, for the development of technologies needed for the Human Exploration and Development of Space, and to improve Earth-bound combustion and fire-safety related technologies.

  3. Sixth International Microgravity Combustion Workshop

    Science.gov (United States)

    Sacksteder, Kurt (Compiler)

    2001-01-01

    This conference proceedings document is a compilation of papers presented orally or as poster displays to the Sixth International Microgravity Combustion Workshop held in Cleveland, Ohio on May 22-24, 2001. The purpose of the workshop is to present and exchange research results from theoretical and experimental work in combustion science using the reduced-gravity environment as a research tool. The results are contributed by researchers funded by NASA throughout the United States at universities, industry and government research agencies, and by researchers from international partner countries that are also participating in the microgravity combustion science research discipline. These research results are intended for use by public and private sector organizations for academic purposes, for the development of technologies needed for Human Exploration and Development of Space, and to improve Earth-bound combustion and fire-safety related technologies.

  4. Smoldering Combustion Experiments in Microgravity

    Science.gov (United States)

    Walther, David C.; Fernandez-Pello, A. Carlos; Urban, David L.

    1997-01-01

    The Microgravity Smoldering Combustion (MSC) experiment is part of a study of the smolder characteristics of porous combustible materials in a microgravity environment. Smoldering is a non-flaming form of combustion that takes place in the interior of porous materials and takes place in a number of processes ranging from smoldering of porous insulation materials to high temperature synthesis of metals. The objective of the study is to provide a better understanding of the controlling mechanisms of smolder, both in microgravity and normal-gravity. As with many forms of combustion, gravity affects the availability of oxidizer and transport of heat, and therefore the rate of combustion. Microgravity smolder experiments, in both a quiescent oxidizing environment, and in a forced oxidizing flow have been conducted aboard the NASA Space Shuttle (STS-69 and STS-77 missions) to determine the effect of the ambient oxygen concentration and oxidizer forced flow velocity on smolder combustion in microgravity. The experimental apparatus is contained within the NASA Get Away Special Canister (GAS-CAN) Payload. These two sets of experiments investigate the propagation of smolder along the polyurethane foam sample under both diffusion driven and forced flow driven smoldering. The results of the microgravity experiments are compared with identical ones carried out in normal gravity, and are used to verify present theories of smolder combustion. The results of this study will provide new insights into the smoldering combustion process. Thermocouple histories show that the microgravity smolder reaction temperatures (Ts) and propagation velocities (Us) lie between those of identical normal-gravity upward and downward tests. These observations indicate the effect of buoyancy on the transport of oxidizer to the reaction front.

  5. Techniques de combustion Combustin Techniques

    Directory of Open Access Journals (Sweden)

    Perthuis E.

    2006-11-01

    Full Text Available L'efficacité d'un processus de chauffage par flamme est étroitement liée à la maîtrise des techniques de combustion. Le brûleur, organe essentiel de l'équipement de chauffe, doit d'une part assurer une combustion complète pour utiliser au mieux l'énergie potentielle du combustible et, d'autre part, provoquer dans le foyer les conditions aérodynamiques les plus propices oux transferts de chaleur. En s'appuyant sur les études expérimentales effectuées à la Fondation de Recherches Internationales sur les Flammes (FRIF, au Groupe d'Étude des Flammes de Gaz Naturel (GEFGN et à l'Institut Français du Pétrole (IFP et sur des réalisations industrielles, on présente les propriétés essentielles des flammes de diffusion aux combustibles liquides et gazeux obtenues avec ou sans mise en rotation des fluides, et leurs répercussions sur les transferts thermiques. La recherche des températures de combustion élevées conduit à envisager la marche à excès d'air réduit, le réchauffage de l'air ou son enrichissement à l'oxygène. Par quelques exemples, on évoque l'influence de ces paramètres d'exploitation sur l'économie possible en combustible. The efficiency of a flame heating process is closely linked ta the mastery of, combustion techniques. The burner, an essential element in any heating equipment, must provide complete combustion sa as to make optimum use of the potential energy in the fuel while, at the same time, creating the most suitable conditions for heat transfers in the combustion chamber. On the basis of experimental research performed by FRIF, GEFGN and IFP and of industrial achievements, this article describesthe essential properties of diffusion flames fed by liquid and gaseous fuels and produced with or without fluid swirling, and the effects of such flames on heat transfers. The search for high combustion temperatures means that consideration must be given to operating with reduced excess air, heating the air or

  6. Jet plume injection and combustion system for internal combustion engines

    Science.gov (United States)

    Oppenheim, Antoni K.; Maxson, James A.; Hensinger, David M.

    1993-01-01

    An improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the cylinder, as well as shortening the time period to attain such a maximum pressure.

  7. Combustion Byproducts Recycling Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Paul Ziemkiewicz; Tamara Vandivort; Debra Pflughoeft-Hassett; Y. Paul Chugh; James Hower

    2008-08-31

    The Combustion Byproducts Recycling Consortium (CBRC) program was developed as a focused program to remove and/or minimize the barriers for effective management of over 123 million tons of coal combustion byproducts (CCBs) annually generated in the USA. At the time of launching the CBRC in 1998, about 25% of CCBs were beneficially utilized while the remaining was disposed in on-site or off-site landfills. During the ten (10) year tenure of CBRC (1998-2008), after a critical review, 52 projects were funded nationwide. By region, the East, Midwest, and West had 21, 18, and 13 projects funded, respectively. Almost all projects were cooperative projects involving industry, government, and academia. The CBRC projects, to a large extent, successfully addressed the problems of large-scale utilization of CCBs. A few projects, such as the two Eastern Region projects that addressed the use of fly ash in foundry applications, might be thought of as a somewhat smaller application in comparison to construction and agricultural uses, but as a novel niche use, they set the stage to draw interest that fly ash substitution for Portland cement might not attract. With consideration of the large increase in flue gas desulfurization (FGD) gypsum in response to EPA regulations, agricultural uses of FGD gypsum hold promise for large-scale uses of a product currently directed to the (currently stagnant) home construction market. Outstanding achievements of the program are: (1) The CBRC successfully enhanced professional expertise in the area of CCBs throughout the nation. The enhanced capacity continues to provide technology and information transfer expertise to industry and regulatory agencies. (2) Several technologies were developed that can be used immediately. These include: (a) Use of CCBs for road base and sub-base applications; (b) full-depth, in situ stabilization of gravel roads or highway/pavement construction recycled materials; and (c) fired bricks containing up to 30%-40% F

  8. Challenges in Propellants and Combustion: 100 Years after Nobel

    National Research Council Canada - National Science Library

    Kuo, Kenneth

    1997-01-01

    .... The Topics covered include: chemical kinetics of propellant combustion, environmental considerations in combustion of solid and liquid propellants, commercial application in the combustion of energetic materials, effective...

  9. Characterisation of wood combustion ashes

    DEFF Research Database (Denmark)

    Maresca, Alberto

    for their composition and leaching properties. Despite the relatively large variations in the contents of nutrients and trace metals, the overall levels were comparable to typical ranges reported in the literature for other wood combustion ashes, as well as with regards to leaching. In general, the composition......The combustion of wood chips and wood pellets for the production of renewable energy in Denmark increased from 5.7 PJ to 16 PJ during the period 2000-2015, and further increases are expected to occur within the coming years. In 2012, about 22,300 tonnes of wood ashes were generated in Denmark....... Currently, these ashes are mainly landfilled, despite Danish legislation allowing their application onto forest and agricultural soils for fertilising and/or liming purposes. During this PhD work, 16 wood ash samples generated at ten different Danish combustion plants were collected and characterised...

  10. Combustion of droplets and sprays

    Science.gov (United States)

    Eigenbrod, Christian; Sattelmayer, Thomas; Bäßler, Stefan; Mauss, Fabian; Meisl, Jürgen; Oomens, Bas; Rackwitz, Leif; Tait, Nigel; Angelberger, Christian; Eilts, Peter; Magnusson, Ingemar; Lauvergne, Romain; Tatschl, Reinhard

    2005-10-01

    The combustion of liquid hydrocarbon fuels in internal combustion engines and gas turbines for energy production and aircraft propulsion is intrinsically tied to the formation of pollutants. Apart from aiming for the highest combustion efficiencies in order to lower the operational costs and the emission of CO2, the reduction of poisonous and environmentally harmful exhaust constituents is a challenging task for scientists and engineers. The most prominent pollutants are soot, identified to trigger respiratory diseases and cancer, and nitric oxides such as NO and NO2, which promote the formation of ozone affecting the cardiovascular system when released in the lower atmosphere. Soot and nitric oxides are greenhouse pollutants in the upper atmosphere. Even though only 2-3% of the anthropogenic emission of nitric oxides are contributed by aircraft, it is the only emission at high altitudes. Unfortunately, it has the greatest impact on climate there and it does not matter whether the fuels are fossil or, in the future, biomass.

  11. Novel Active Combustion Control Valve

    Science.gov (United States)

    Caspermeyer, Matt

    2014-01-01

    This project presents an innovative solution for active combustion control. Relative to the state of the art, this concept provides frequency modulation (greater than 1,000 Hz) in combination with high-amplitude modulation (in excess of 30 percent flow) and can be adapted to a large range of fuel injector sizes. Existing valves often have low flow modulation strength. To achieve higher flow modulation requires excessively large valves or too much electrical power to be practical. This active combustion control valve (ACCV) has high-frequency and -amplitude modulation, consumes low electrical power, is closely coupled with the fuel injector for modulation strength, and is practical in size and weight. By mitigating combustion instabilities at higher frequencies than have been previously achieved (approximately 1,000 Hz), this new technology enables gas turbines to run at operating points that produce lower emissions and higher performance.

  12. MODELAGEM DE PROCESSOS UTILIZANDO O BPMN NA FACULDADE CATÓLICA RAINHA DO SERTÃO

    National Research Council Canada - National Science Library

    Antonio Neuton da Silva Júnior; Carlos Henrique Leitão Cavalcante; Gabriela Cíntia Cavalcante de Lima; Thiago Almeida Costa; Stephanie Barros de Freitas

    2017-01-01

    O presente artigo apresenta o gerenciamento de negócios por processos, suas perspectivas atuais, suas vantagens, o desenvolvimento do projeto Modelagem de Processos utilizando BPMN implementado na Faculdade Católica Rainha...

  13. Autodesk Combustion 4 fundamentals courseware

    CERN Document Server

    Autodesk,

    2005-01-01

    Whether this is your first experience with Combustion software or you're upgrading to take advantage of the many new features and tools, this guide will serve as your ultimate resource to this all-in-one professional compositing application. Much more than a point-and-click manual, this guide explains the principles behind the software, serving as an overview of the package and associated techniques. Written by certified Autodesk training specialists for motion graphic designers, animators, and visual effects artists, Combustion 4 Fundamentals Courseware provides expert advice for all skill le

  14. Chemical kinetics and combustion modeling

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.A. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    The goal of this program is to gain qualitative insight into how pollutants are formed in combustion systems and to develop quantitative mathematical models to predict their formation rates. The approach is an integrated one, combining low-pressure flame experiments, chemical kinetics modeling, theory, and kinetics experiments to gain as clear a picture as possible of the process in question. These efforts are focused on problems involved with the nitrogen chemistry of combustion systems and on the formation of soot and PAH in flames.

  15. Catalytic Combustion of Ethyl Acetate

    OpenAIRE

    ÖZÇELİK, Tuğba GÜRMEN; ATALAY, Süheyda; ALPAY, Erden

    2014-01-01

    The catalytic combustion of ethyl acetate over prepared metal oxide catalysts was investigated. CeO, Co2O3, Mn2O3, Cr2O3, and CeO-Co2O3 catalysts were prepared on monolith supports and they were tested. Before conducting the catalyst experiments, we searched for the homogeneous gas phase combustion reaction of ethyl acetate. According to the homogeneous phase experimental results, 45% of ethyl acetate was converted at the maximum reactor temperature tested (350 °C). All the prepare...

  16. Application of the FIRST Combustion model to Spray Combustion

    NARCIS (Netherlands)

    de Jager, B.; Kok, Jacobus B.W.

    2004-01-01

    Liquid fuel is of interest to apply to gas turbines. The large advantage is that liquids are easily storable as compared to gaseous fuels. Disadvantage is that liquid fuel has to be sprayed, vaporized and mixed with air. Combustion occurs at some stage of mixing and ignition. Depending on the

  17. Scramjet Combustion Stability Behavior Modeling Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A recent breakthrough in combustion stability analysis (UCDS) offers the means to accurately predict the combustion stability of a scramjet. This capability is very...

  18. Scramjet Combustion Stability Behavior Modeling Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A recent breakthrough in combustion stability analysis (UCDS) offers the potential to predict the combustion stability of a scramjet. This capability is very...

  19. Free Energy and Internal Combustion Engine Cycles

    OpenAIRE

    Harris, William D.

    2012-01-01

    The performance of one type (Carnot) of Internal Combustion Engine (ICE) cycle is analyzed within the framework of thermodynamic free energies. ICE performance is different from that of an External Combustion Engine (ECE) which is dictated by Carnot's rule.

  20. High Frequency Combustion Instabilities of LOx/CH4 Spray Flames in Rocket Engine Combustion Chambers

    NARCIS (Netherlands)

    Sliphorst, M.

    2011-01-01

    Ever since the early stages of space transportation in the 1940’s, and the related liquid propellant rocket engine development, combustion instability has been a major issue. High frequency combustion instability (HFCI) is the interaction between combustion and the acoustic field in the combustion

  1. Method and device for diagnosing and controlling combustion instabilities in internal combustion engines operating in or transitioning to homogeneous charge combustion ignition mode

    Science.gov (United States)

    Wagner, Robert M [Knoxville, TN; Daw, Charles S [Knoxville, TN; Green, Johney B [Knoxville, TN; Edwards, Kevin D [Knoxville, TN

    2008-10-07

    This invention is a method of achieving stable, optimal mixtures of HCCI and SI in practical gasoline internal combustion engines comprising the steps of: characterizing the combustion process based on combustion process measurements, determining the ratio of conventional and HCCI combustion, determining the trajectory (sequence) of states for consecutive combustion processes, and determining subsequent combustion process modifications using said information to steer the engine combustion toward desired behavior.

  2. Aplicaciones de electrodos enzimáticos y multicapas enzimáticas en biosensores y bioceldas de combustible

    OpenAIRE

    Scodeller, Pablo David

    2011-01-01

    El presente trabajo de tesis se basa en el estudio de multicapas enzimáticas y electrodos enzimáticos destinados a la fabricación de biosensores y biocátodos para celdas de combustible. Las multicapas, de espesores nanométricos, se fabricaron utilizando el método de autoensamblado capa por capa, empleando enzimas y el polielectrolito electroactivo PAH-Os. El primer objetivo es extender el sistema de reconocimiento molecular de glucosa integrado por una enzima redox (GOx) mediada por su cable ...

  3. Straw combustion on slow-moving grates

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen

    2005-01-01

    Combustion of straw in grate-based boilers is often associated with high emission levels and relatively poor fuel burnout. A numerical grate combustion model was developed to assist in improving the combustion performance of these boilers. The model is based on a one-dimensional ‘‘walking...

  4. 30 CFR 56.4104 - Combustible waste.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Combustible waste. 56.4104 Section 56.4104... Control Prohibitions/precautions/housekeeping § 56.4104 Combustible waste. (a) Waste materials, including... properly, waste or rags containing flammable or combustible liquids that could create a fire hazard shall...

  5. Laboratory Test of Reciprocating Internal Combustion Engines

    Science.gov (United States)

    2016-02-04

    700, Laboratory Tests of Reciprocating Internal Combustion Engines , dated 24 January 1985. Marginal notations are not used in this revision to...performance and endurance of reciprocating internal combustion engines . Test equipment includes engine dynamometers, precision fuel flow meters, oil...D-1 *This TOP supersedes TOP 02-2-700, Laboratory Tests of Reciprocating Internal Combustion Engines , dated 24

  6. Furnaces with multiple ?ameless combustion burners

    NARCIS (Netherlands)

    Danon, B.

    2011-01-01

    In this thesis three different combustion systems, equipped with either a single or multiple ?ameless combustion burner(s), are discussed. All these setups were investigated both experimentally and numerically, i.e., using Computational Fluid Dynamics (CFD) simulations. Flameless combustion is a

  7. Sulfur Chemistry in Combustion II

    DEFF Research Database (Denmark)

    Johnsson, Jan Erik; Kiil, Søren

    2000-01-01

    Several options are available to control the emission of SO2 from combustion processes. One possibility is to use a cleaner technology, i.e. fuel switching from oil and coal to natural gas or biomass, or to desulphurize coal and oil. Another possibility is to change to a different technology...

  8. Structural Analysis of Combustion Models

    CERN Document Server

    Tóth, J; Zsély, I

    2013-01-01

    Using ReactionKinetics, a Mathematica based package a few dozen detailed models for combustion of hydrogen, carbon monoxide and methanol are investigated. Essential structural characteristics are pulled out, and similarities and differences of the mechanisms are highlighted. These investigations can be used before or parallel with usual numerical investigations, such as pathway analysis, sensitivity analysis, parameter estimation, or simulation.

  9. 75 FR 3881 - Combustible Dust

    Science.gov (United States)

    2010-01-25

    ... may form combustible dust include, but are not limited to, wood, coal, plastics, biosolids, candy..., pharmaceutical manufacturing, tire manufacturing, production of rubber and plastics, plastics and rubber products manufacturing, recycling, wastewater treatment, and coal handling. OSHA is developing a standard that will...

  10. Environmental optimisation of waste combustion

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, Robert [AaF Energikonsult, Stockholm (Sweden); Berge, Niclas; Stroemberg, Birgitta [TPS Termiska Processer AB, Nykoeping (Sweden)

    2000-12-01

    The regulations concerning waste combustion evolve through R and D and a strive to get better and common regulations for the European countries. This study discusses if these rules of today concerning oxygen concentration, minimum temperature and residence time in the furnace and the use of stand-by burners are needed, are possible to monitor, are the optimum from an environmental point of view or could be improved. No evidence from well controlled laboratory experiments validate that 850 deg C in 6 % oxygen content in general is the best lower limit. A lower excess air level increase the temperature, which has a significant effect on the destruction of hydrocarbons, favourably increases the residence time, increases the thermal efficiency and the efficiency of the precipitators. Low oxygen content is also necessary to achieve low NO{sub x}-emissions. The conclusion is that the demands on the accuracy of the measurement devices and methods are too high, if they are to be used inside the furnace to control the combustion process. The big problem is however to find representative locations to measure temperature, oxygen content and residence time in the furnace. Another major problem is that the monitoring of the operation conditions today do not secure a good combustion. It can lead to a false security. The reason is that it is very hard to find boilers without stratifications. These stratifications (stream lines) has each a different history of residence time, mixing time, oxygen and combustible gas levels and temperature, when they reach the convection area. The combustion result is the sum of all these different histories. The hydrocarbons emission is in general not produced at a steady level. Small clouds of unburnt hydrocarbons travels along the stream lines showing up as peaks on a THC measurement device. High amplitude peaks has a tendency to contain higher ratio of heavy hydrocarbons than lower peaks. The good correlation between some easily detected

  11. El proceso de sustitución de combustibles pesados por gas natural en el sector industrial del Valle del Cauca y del Cauca - Colombia 2004-2012

    Directory of Open Access Journals (Sweden)

    Andrés Eduardo Rangel Jiménez

    2016-01-01

    Full Text Available Este documento tiene por objetivo analizar el proceso de sustitución de la utilización de combustibles pesados hacia el gas natural por parte de medianas y grandes empresas ubicadas en el Valle del Cauca y norte del Cauca, que se observan durante el periodo 2004-2012. Asimismo, utilizando un modelo Probit de efectos aleatorios en Panel, se estima la propensión de estas industrias a sustituir un combustible altamente contaminante por gas natural. Los resultados muestran que la diferencia de gasto en gas con relación a otros combustibles es determinante en la probabilidad de conversión. Adicionalmente, se confirma que las industrias con menos probabilidad de realizar la conversión son aquellas que utilizan carbón en los procesos de producción.

  12. Gaseous emissions from waste combustion.

    Science.gov (United States)

    Werther, Joachim

    2007-06-18

    An overview is given on methods and technologies for limiting the gaseous emissions from waste combustion. With the guideline 2000/76/EC recent European legislation has set stringent limits not only for the mono-combustion of waste in specialized incineration plants but also for co-combustion in coal-fired power plants. With increased awareness of environmental issues and stepwise decrease of emission limits and inclusion of more and more substances into the network of regulations a multitude of emission abatement methods and technologies have been developed over the last decades. The result is the state-of-the-art waste incinerator with a number of specialized process steps for the individual components in the flue gas. The present work highlights some new developments which can be summarized under the common goal of reducing the costs of flue gas treatment by applying systems which combine the treatment of several noxious substances in one reactor or by taking new, simpler routes instead of the previously used complicated ones or - in the case of flue gas desulphurisation - by reducing the amount of limestone consumption. Cost reduction is also the driving force for new processes of conditioning of nonhomogenous waste before combustion. Pyrolysis or gasification is used for chemical conditioning whereas physical conditioning means comminution, classification and sorting processes. Conditioning yields a fuel which can be used in power plants either as a co-fuel or a mono-fuel and which will burn there under much better controlled conditions and therefore with less emissions than the nonhomogeneous waste in a conventional waste incinerator. Also for cost reasons, co-combustion of wastes in coal-fired power stations is strongly pressing into the market. Recent investigations reveal that the co-firing of waste can also have beneficial effects on the operating behavior of the boiler and on the gaseous emissions.

  13. Light Duty Efficient, Clean Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Donald Stanton

    2010-12-31

    Cummins has successfully completed the Light Duty Efficient Clean Combustion (LDECC) cooperative program with DoE. This program was established in 2007 in support of the Department of Energy's Vehicles Technologies Advanced Combustion and Emissions Control initiative to remove critical barriers to the commercialization of advanced, high efficiency, emissions compliant internal combustion (IC) engines for light duty vehicles. Work in this area expanded the fundamental knowledge of engine combustion to new regimes and advanced the knowledge of fuel requirements for these diesel engines to realize their full potential. All of the following objectives were met with fuel efficiency improvement targets exceeded: (1) Improve light duty vehicle (5000 lb. test weight) fuel efficiency by 10.5% over today's state-of-the-art diesel engine on the FTP city drive cycle; (2) Develop and design an advanced combustion system plus aftertreatment system that synergistically meets Tier 2 Bin 5 NOx and PM emissions standards while demonstrating the efficiency improvements; (3) Maintain power density comparable to that of current conventional engines for the applicable vehicle class; and (4) Evaluate different fuel components and ensure combustion system compatibility with commercially available biofuels. Key accomplishments include: (1) A 25% improvement in fuel efficiency was achieved with the advanced LDECC engine equipped with a novel SCR aftertreatment system compared to the 10.5% target; (2) An 11% improvement in fuel efficiency was achieved with the advanced LDECC engine and no NOx aftertreamtent system; (3) Tier 2 Bin 5 and SFTP II emissions regulations were met with the advanced LDECC engine equipped with a novel SCR aftertreatment system; (4) Tier 2 Bin 5 emissions regulations were met with the advanced LDECC engine and no NOx aftertreatment, but SFTP II emissions regulations were not met for the US06 test cycle - Additional technical barriers exist for the no NOx

  14. Combustion Aerosols from Pulverised Coal Combustion and Biomass Grate Combustion. Filtration aspects

    Energy Technology Data Exchange (ETDEWEB)

    Lillieblad, Lena [Vaexjoe Univ. (Sweden). Div. of Bioenergy Technology

    2005-06-01

    Combustion processes generate particles, which are formed both from the inorganic content in the fuel and from organic compounds as a result of incomplete combustion. The particles are removed from the flue gas by cyclones, electrostatic precipitators (ESPs) or fabric filters (FFs). The particle removal capacity is strongly depending on the particle properties, operating conditions and selected particle removal technology. The particle properties are depending on fuel type, combustion technique and combustion conditions. In this study the particle properties for two different types of solid fuel combustion were investigated and compared. The two processes were pulverised coal combustion and grate boilers operating on woody biomass. Characterisation of fuels was made both with standard analyses and more sophisticated methods like computer controlled scanning electron microscopy (CCSEM) and subsequent leaching procedures. A major difference between coal and woody biomass is the occurrence of potassium. In woody biofuel potassium is a reactive components, mainly water-soluble or organically associated, whereas it in coal it is associated to minerals like illite. The particle number size and particle mass size distributions were measured with low-pressure impactors (LPI), electrical mobility analysers and electrical low-pressure impactors (ELPI). The submicrometer particle mass concentration was similar for the two combustion processes. There is a difference between different coals and also between different woody biofuels. The coarse particle fraction is considerably larger for coal combustion, due to the high content of minerals in the coal. Potassium, sulphur and chlorine dominate the submicrometer particle chemical composition from wood fired grate boilers. Coarser particles have a high content of calcium. Silicon and aluminium are the major elements in particles from pulverised coal combustion. An enrichment of calcium, sulphur and phosphorous in the submicrometer

  15. Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Ojeda, William de

    2010-07-31

    The project which extended from November 2005 to May of 2010 demonstrated the application of Low Temperature Combustion (LTC) with engine out NOx levels of 0.2 g/bhp-hr throughout the program target load of 12.6bar BMEP. The project showed that the range of loads could be extended to 16.5bar BMEP, therefore matching the reference lug line of the base 2007 MY Navistar 6.4L V8 engine. Results showed that the application of LTC provided a dramatic improvement over engine out emissions when compared to the base engine. Furthermore LTC improved thermal efficiency by over 5% from the base production engine when using the steady state 13 mode composite test as a benchmark. The key enablers included improvements in the air, fuel injection, and cooling systems made in Phases I and II. The outcome was the product of a careful integration of each component under an intelligent control system. The engine hardware provided the conditions to support LTC and the controller provided the necessary robustness for a stable combustion. Phase III provided a detailed account on the injection strategy used to meet the high load requirements. During this phase, the control strategy was implemented in a production automotive grade ECU to perform cycle-by-cycle combustion feedback on each of the engine cylinders. The control interacted on a cycle base with the injection system and with the Turbo-EGR systems according to their respective time constants. The result was a unique system that could, first, help optimize the combustion system and maintain high efficiency, and secondly, extend the steady state results to the transient mode of operation. The engine was upgraded in Phase IV with a Variable Valve Actuation system and a hybrid EGR loop. The impact of the more versatile EGR loop did not provide significant advantages, however the application of VVA proved to be an enabler to further extend the operation of LTC and gain considerable benefits in fuel economy and soot reduction. Finally

  16. Microscale combustion and power generation

    CERN Document Server

    Cadou, Christopher; Ju, Yiguang

    2014-01-01

    Recent advances in microfabrication technologies have enabled the development of entirely new classes of small-scale devices with applications in fields ranging from biomedicine, to wireless communication and computing, to reconnaissance, and to augmentation of human function. In many cases, however, what these devices can actually accomplish is limited by the low energy density of their energy storage and conversion systems. This breakthrough book brings together in one place the information necessary to develop the high energy density combustion-based power sources that will enable many of these devices to realize their full potential. Engineers and scientists working in energy-related fields will find: An overview of the fundamental physics and phenomena of microscale combustion; Presentations of the latest modeling and simulation techniques for gasphase and catalytic micro-reactors; The latest results from experiments in small-scale liquid film, microtube, and porous combustors, micro-thrusters, a...

  17. Fundamental studies of spray combustion

    Energy Technology Data Exchange (ETDEWEB)

    Li, S.C.; Libby, P.A.; Williams, F.A. [Univ. of California, San Diego, CA (United States)

    1997-12-31

    Our research on spray combustion involves both experiment and theory and addresses the characteristics of individual droplets and of sprays in a variety of flows: laminar and turbulent, opposed and impinging. Currently our focus concerns water and fuel sprays in two stage laminar flames, i.e., flames arising, for example from a stream of fuel and oxidizer flowing opposite to an air stream carrying a water spray. Our interest in these flames is motivated by the goals of reducing pollutant emissions and extending the range of stable spray combustion. There remains considerable research to be carried out in order to achieve these goals. Thus far our research on the characteristics of sprays in turbulent flows has been limited to nonreacting jets impinging on a plate but this work will be extended to opposed flows with and without a flame. In the following we discuss details of these studies and our plans for future work.

  18. Oxy-coal Combustion Studies

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, J. [Univ. of Utah, Salt Lake City, UT (United States); Eddings, E. [Univ. of Utah, Salt Lake City, UT (United States); Lighty, J. [Univ. of Utah, Salt Lake City, UT (United States); Ring, T. [Univ. of Utah, Salt Lake City, UT (United States); Smith, P. [Univ. of Utah, Salt Lake City, UT (United States); Thornock, J. [Univ. of Utah, Salt Lake City, UT (United States); Y Jia, W. Morris [Univ. of Utah, Salt Lake City, UT (United States); Pedel, J. [Univ. of Utah, Salt Lake City, UT (United States); Rezeai, D. [Univ. of Utah, Salt Lake City, UT (United States); Wang, L. [Univ. of Utah, Salt Lake City, UT (United States); Zhang, J. [Univ. of Utah, Salt Lake City, UT (United States); Kelly, K. [Univ. of Utah, Salt Lake City, UT (United States)

    2012-01-06

    The objective of this project is to move toward the development of a predictive capability with quantified uncertainty bounds for pilot-scale, single-burner, oxy-coal operation. This validation research brings together multi-scale experimental measurements and computer simulations. The combination of simulation development and validation experiments is designed to lead to predictive tools for the performance of existing air fired pulverized coal boilers that have been retrofitted to various oxy-firing configurations. In addition, this report also describes novel research results related to oxy-combustion in circulating fluidized beds. For pulverized coal combustion configurations, particular attention is focused on the effect of oxy-firing on ignition and coal-flame stability, and on the subsequent partitioning mechanisms of the ash aerosol.

  19. Combustion synthesis continuous flow reactor

    Energy Technology Data Exchange (ETDEWEB)

    Maupin, G.D.; Chick, L.A.; Kurosky, R.P.

    1998-01-06

    The present invention is a reactor for combustion synthesis of inorganic powders. The reactor includes a reaction vessel having a length and a first end and a second end. The reaction vessel further has a solution inlet and a carrier gas inlet. The reactor further has a heater for heating both the solution and the carrier gas. In a preferred embodiment, the reaction vessel is heated and the solution is in contact with the heated reaction vessel. It is further preferred that the reaction vessel be cylindrical and that the carrier gas is introduced tangentially into the reaction vessel so that the solution flows helically along the interior wall of the reaction vessel. As the solution evaporates and combustion produces inorganic material powder, the carrier gas entrains the powder and carries it out of the reactor. 10 figs.

  20. Combustion synthesis continuous flow reactor

    Energy Technology Data Exchange (ETDEWEB)

    Maupin, Gary D. (Richland, WA); Chick, Lawrence A. (West Richland, WA); Kurosky, Randal P. (Maple Valley, WA)

    1998-01-01

    The present invention is a reactor for combustion synthesis of inorganic powders. The reactor includes a reaction vessel having a length and a first end and a second end. The reaction vessel further has a solution inlet and a carrier gas inlet. The reactor further has a heater for heating both the solution and the carrier gas. In a preferred embodiment, the reaction vessel is heated and the solution is in contact with the heated reaction vessel. It is further preferred that the reaction vessel be cylindrical and that the carrier gas is introduced tangentially into the reaction vessel so that the solution flows helically along the interior wall of the reaction vessel. As the solution evaporates and combustion produces inorganic material powder, the carrier gas entrains the powder and carries it out of the reactor.

  1. Steady Nuclear Combustion in Rockets

    Science.gov (United States)

    Saenger, E.

    1957-01-01

    The astrophysical theory of stationary nuclear reactions in stars is applied to the conditions that would be met in the practical engineering cases that would differ from the former, particularly with respect to the much lower combustion pressures, dimensions of the reacting volume, and burnup times. This application yields maximum rates of hear production per unit volume of reacting gas occurring at about 10(exp 8) K in the cases of reactions between the hydrogen isotopes, but yields higher rates for heavier atoms. For the former, with chamber pressures of the order of 100 atmospheres, the energy production for nuclear combustion reaches values of about 10(exp 4) kilocalories per cubic meter per second, which approaches the magnitude for the familiar chemical fuels. The values are substantially lower for heavier atoms, and increase with the square of the combustion pressure. The half-life of the burnup in the fastest reactions may drop to values as low as those for chemical fuels so that, despite the high temperature, the radiated energy can remain smaller than the energy produced, particularly if an inefficiently radiating (i.e., easily completely ionized reacting material like hydrogen), is used. On the other hand, the fraction of completely ionized particles in the gases undergoing nuclear combustion must not exceed a certain upper limit because the densities (approximately 10(exp -10) grams per cubic centimeter)) lie in the range of high vacua and only for the previously mentioned fraction of nonionized particles can mean free paths be retained small enough so that the chamber diameters of several dozen meters will suffice. Under these conditions it appears that continuously maintained stable nuclear reactions at practical pressures and dimensions are fundamentally possible and their application can be visualized as energy sources for power plants and propulsion units.

  2. Coal combustion by wet oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Bettinger, J.A.; Lamparter, R.A.; McDowell, D.C.

    1980-11-15

    The combustion of coal by wet oxidation was studied by the Center for Waste Management Programs, of Michigan Technological University. In wet oxidation a combustible material, such as coal, is reacted with oxygen in the presence of liquid water. The reaction is typically carried out in the range of 204/sup 0/C (400/sup 0/F) to 353/sup 0/C (650/sup 0/F) with sufficient pressure to maintain the water present in the liquid state, and provide the partial pressure of oxygen in the gas phase necessary to carry out the reaction. Experimental studies to explore the key reaction parameters of temperature, time, oxidant, catalyst, coal type, and mesh size were conducted by running batch tests in a one-gallon stirred autoclave. The factors exhibiting the greatest effect on the extent of reaction were temperature and residence time. The effect of temperature was studied from 204/sup 0/C (400/sup 0/F) to 260/sup 0/C (500/sup 0/F) with a residence time from 600 to 3600 seconds. From this data, the reaction activation energy of 2.7 x 10/sup 4/ calories per mole was determined for a high-volatile-A-Bituminous type coal. The reaction rate constant may be determined at any temperature from the activation energy using the Arrhenius equation. Additional data were generated on the effect of mesh size and different coal types. A sample of peat was also tested. Two catalysts were evaluated, and their effects on reaction rate presented in the report. In addition to the high temperature combustion, low temperature desulfurization is discussed. Desulfurization can improve low grade coal to be used in conventional combustion methods. It was found that 90% of the sulfur can be removed from the coal by wet oxidation with the carbon untouched. Further desulfurization studies are indicated.

  3. Status of Boron Combustion Research

    Science.gov (United States)

    1984-10-01

    Chemical M. K. King, ARC L. Cook, NBS C. E. Kolb, Aerodyne *T. Curran, AFWAL/PO C. K. Law, U. Cal.-Davi3 P. Davidovits , Boston College *C. R. Martel...Homogeneous Combustion Kinetics of Boron Compounds. A. Fontijn, RPI. 1030 Simple Boron Atom Reactions. P. Davidovits , Boston College. 1050 Ultra-Fast Energy... DAVIDOVITS . J. Chem. Phys. 74, 3287 (1981). DED - T. G. DIGIUSEPPI. Rt. ESTES, and P. DAVIDOVITS . J. Phys. Chem.. 6, 260 (1982). ERF -A. J. ENGLISH

  4. Perspective -- Aerodynamic control of combustion

    Energy Technology Data Exchange (ETDEWEB)

    Oppenheim, A.K. [Univ. of California, Berkeley, CA (United States). Mechanical Engineering

    1993-12-01

    To do useful work, the exothermic process of combustion should be carried out in an enclosure, as is typically the case with i.c. engines -- the subject of this paper`s particular concern. To meet the requirements of high efficiency and low pollutant production, this process should be executed at a relatively low temperature -- a condition attainable by the use of lean air-fuel mixtures. For this purpose it has to be distributed in space upon multipoint initiation and kept away from the walls to minimize their detrimental effects. In principle, all this can be accomplished by a system referred to as fireball combustion that takes advantage of entrainment and spiral mixing associated with large scale vortex structures of jet plumes. As demonstrated in this paper, the success in such an endeavor depends crucially upon the utilization of the essential elements of classical aerodynamics: the properly distributed sources, expressed in terms of velocity divergences prescribed by the thermodynamic process of combustion and of the vorticity field generated by shear between the jets and the fluid into which they are injected.

  5. Combustion instability modeling and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Santoro, R.J.; Yang, V.; Santavicca, D.A. [Pennsylvania State Univ., University Park, PA (United States)] [and others

    1995-10-01

    It is well known that the two key elements for achieving low emissions and high performance in a gas turbine combustor are to simultaneously establish (1) a lean combustion zone for maintaining low NO{sub x} emissions and (2) rapid mixing for good ignition and flame stability. However, these requirements, when coupled with the short combustor lengths used to limit the residence time for NO formation typical of advanced gas turbine combustors, can lead to problems regarding unburned hydrocarbons (UHC) and carbon monoxide (CO) emissions, as well as the occurrence of combustion instabilities. Clearly, the key to successful gas turbine development is based on understanding the effects of geometry and operating conditions on combustion instability, emissions (including UHC, CO and NO{sub x}) and performance. The concurrent development of suitable analytical and numerical models that are validated with experimental studies is important for achieving this objective. A major benefit of the present research will be to provide for the first time an experimentally verified model of emissions and performance of gas turbine combustors.

  6. Demonstration of Active Combustion Control

    Science.gov (United States)

    Lovett, Jeffrey A.; Teerlinck, Karen A.; Cohen, Jeffrey M.

    2008-01-01

    The primary objective of this effort was to demonstrate active control of combustion instabilities in a direct-injection gas turbine combustor that accurately simulates engine operating conditions and reproduces an engine-type instability. This report documents the second phase of a two-phase effort. The first phase involved the analysis of an instability observed in a developmental aeroengine and the design of a single-nozzle test rig to replicate that phenomenon. This was successfully completed in 2001 and is documented in the Phase I report. This second phase was directed toward demonstration of active control strategies to mitigate this instability and thereby demonstrate the viability of active control for aircraft engine combustors. This involved development of high-speed actuator technology, testing and analysis of how the actuation system was integrated with the combustion system, control algorithm development, and demonstration testing in the single-nozzle test rig. A 30 percent reduction in the amplitude of the high-frequency (570 Hz) instability was achieved using actuation systems and control algorithms developed within this effort. Even larger reductions were shown with a low-frequency (270 Hz) instability. This represents a unique achievement in the development and practical demonstration of active combustion control systems for gas turbine applications.

  7. Modeling the internal combustion engine

    Science.gov (United States)

    Zeleznik, F. J.; Mcbride, B. J.

    1985-01-01

    A flexible and computationally economical model of the internal combustion engine was developed for use on large digital computer systems. It is based on a system of ordinary differential equations for cylinder-averaged properties. The computer program is capable of multicycle calculations, with some parameters varying from cycle to cycle, and has restart capabilities. It can accommodate a broad spectrum of reactants, permits changes in physical properties, and offers a wide selection of alternative modeling functions without any reprogramming. It readily adapts to the amount of information available in a particular case because the model is in fact a hierarchy of five models. The models range from a simple model requiring only thermodynamic properties to a complex model demanding full combustion kinetics, transport properties, and poppet valve flow characteristics. Among its many features the model includes heat transfer, valve timing, supercharging, motoring, finite burning rates, cycle-to-cycle variations in air-fuel ratio, humid air, residual and recirculated exhaust gas, and full combustion kinetics.

  8. Method and apparatus for active control of combustion rate through modulation of heat transfer from the combustion chamber wall

    Science.gov (United States)

    Roberts, Jr., Charles E.; Chadwell, Christopher J.

    2004-09-21

    The flame propagation rate resulting from a combustion event in the combustion chamber of an internal combustion engine is controlled by modulation of the heat transfer from the combustion flame to the combustion chamber walls. In one embodiment, heat transfer from the combustion flame to the combustion chamber walls is mechanically modulated by a movable member that is inserted into, or withdrawn from, the combustion chamber thereby changing the shape of the combustion chamber and the combustion chamber wall surface area. In another embodiment, heat transfer from the combustion flame to the combustion chamber walls is modulated by cooling the surface of a portion of the combustion chamber wall that is in close proximity to the area of the combustion chamber where flame speed control is desired.

  9. COMBUSTION SIMULATION IN A SPARK IGNITION ENGINE CYLINDER: EFFECTS OF AIR-FUEL RATIO ON THE COMBUSTION DURATION

    OpenAIRE

    Nureddin Dinler; Nuri Yucel

    2010-01-01

    Combustion is an important subject of internal combustion engine studies. To reduce the air pollution from internal combustion engines and to increase the engine performance, it is required to increase combustion efficiency. In this study, effects of air/fuel ratio were investigated numerically. An axisymmetrical internal combustion engine was modeled in order to simulate in-cylinder engine flow and combustion. Two dimensional transient continuity, momentum, turbulence, energy, and combustion...

  10. Particle Emissions from Biomass Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Szpila, Aneta; Bohgard, Mats [Lund Inst. of Technology (Sweden). Div. of Ergonomics and Aerosol Technology; Strand, Michael; Lillieblad, Lena; Sanati, Mehri [Vaexjoe Univ. (Sweden). Div. of Bioenergy Technology; Pagels, Joakim; Rissler, Jenny; Swietlicki, Erik; Gharibi, Arash [Lund Univ. (Sweden). Div. of Nuclear Physics

    2003-05-01

    We have shown that high concentrations of fine particles of the order of 2-7x10{sup -7} particles per cm{sup 3} are being formed in all the combustion units studied. There was a higher difference between the units in terms of particle mass concentrations. While the largest differences was found for gas-phase constituents (CO and THC) and polyaromatic hydrocarbons. In 5 out of 7 studied units, multi-cyclones were the only measure for flue-gas separation. The multicyclones had negligible effect on the particle number concentration and a small effect on the mass of particles smaller than 5 {mu}m. The separation efficiency was much higher for the electrostatic precipitators. The boiler load had a dramatic influence on the coarse mode concentration during combustion of forest residue. PM0.8-6 increased from below 5 mg/m{sup 3} to above 50 mg/m{sup 3} even at a moderate change in boiler load from medium to high. A similar but less pronounced trend was found during combustion of dry wood. PM0.8-PM6 increased from 12 to 23 mg/m{sup 3} when the load was changed from low to high. When increasing the load, the primary airflow taken through the grate is increased; this itself may lead to a higher potential of the air stream to carry coarse particles away from the combustion zone. Measurements with APS-instrument with higher time-resolution showed a corresponding increase in coarse mode number concentration with load. Additional factor influencing observed higher concentration of coarse mode during combustion of forest residues, could be relatively high ash content in this type of fuel (2.2 %) in comparison to dry wood (0.3 %) and pellets (0.5 %). With increasing load we also found a decrease in PM1 during combustion of forest residue. Whether this is caused by scavenging of volatilized material by the high coarse mode concentration or a result of a different amount of volatilized material available for formation of fine particles needs to be shown in future studies. The

  11. TOXIC SUBSTANCES FROM COAL COMBUSTION

    Energy Technology Data Exchange (ETDEWEB)

    A KOLKER; AF SAROFIM; CL SENIOR; FE HUGGINS; GP HUFFMAN; I OLMEZ; J LIGHTY; JOL WENDT; JOSEPH J HELBLE; MR AMES; N YAP; R FINKELMAN; T PANAGIOTOU; W SEAMES

    1998-12-08

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the Federal Energy Technology Center (FETC), the Electric Power Research Institute, the Lignite Research Council, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NO combustion systems, and new power generation x plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). This report covers the reporting period from 1 July 1998 through 30 September 1998. During this period distribution of all three Phase II coals was completed. Standard analyses for the whole coal samples were also completed. Mössbauer analysis of all project coals and fractions received to date has been completed in order to obtain details of the iron mineralogy. The analyses of arsenic XAFS data for two of the project coals and for some high arsenic coals have been completed. Duplicate splits of the Ohio 5,6,7 and North Dakota lignite samples were taken through all four steps of the selective leaching procedure. Leaching analysis of the Wyodak coal has recently commenced. Preparation of polished coal/epoxy pellets for probe/SEM studies is underway. Some exploratory mercury LIII XAFS work was

  12. Propuesta de aplicaciones futuras en hogares digitales utilizando el protocolo IPv6

    OpenAIRE

    Proa?o Garay, Marco Antonio

    2014-01-01

    El presente trabajo de investigaci?n, consiste en la elaboraci?n de una propuesta de aplicaciones futuras en hogares digitales, utilizando el protocolo de internet IPV6, en donde se analizan aquellas tecnolog?as de acceso a internet y a redes en el hogar, para luego proponer tres dise?os te?ricos, aplicados al hogar digital, siendo el primero, la conectividad utilizando el protocolo IpV6, de una red domotica con c?maras IP inal?mbricas y dispositivos m?viles, el segundo, la conectividad utili...

  13. Dieta cetogênica utilizando jejum fracionado: emprego ambulatorial em epilepsia refratária

    OpenAIRE

    Barros, Carlos Roberto de Moraes Rego

    2006-01-01

    Introdução Estudos experimentais clássicos têm sido realizados desde o início do século passado, utilizando métodos alternativos para tratamento das epilepsias. Entre eles, o emprego de uma dieta, denominada dieta cetogênica, que mimetizando os efeitos de um jejum prolongado, provoca a produção de corpos cetônicos, que seriam responsáveis por inibir a hiperexcitabilidade neuronal. Baseado nestes conceitos metabólicos e bioquímicos, foi aplicado tratamento utilizando dieta cetogênica em pacien...

  14. Síntese alternativa de ZSM-5 utilizando sementes e etanol como codirecionador de estrutura

    OpenAIRE

    Albiero, Jalusa Konzen; Coutinho, Elisa Barbosa; Schwaab, Marcio; de Castilhos, Fernanda

    2015-01-01

    Neste trabalho, propõem-se a síntese de zeólitas do tipo ZSM-5 utilizando cristais deste material, como sementes, e etanol, em substituição às usuais bases orgânicas nitrogenadas como direcionadores de estrutura. As sementes foram sintetizadas pelo método hidrotérmico empregando n-butilamina como direcionador de estrutura. Utilizando as sementes e o etanol, como codirecionador, foi realizada a síntese de ZSM-5, tendo, como fonte de sílica, cinza de casca de arroz e, como fonte de alumínio, ca...

  15. Síntese alternativa de ZSM-5 utilizando sementes e etanol como codirecionador de estrutura

    OpenAIRE

    Albiero, Jalusa Konzen; Schwaab, Marcio; de Castilhos, Fernanda; Coutinho, Elisa Barbosa

    2015-01-01

    Neste trabalho, propõem-se a síntese de zeólitas do tipo ZSM-5 utilizando cristais deste material como sementes e etanol, em substituição às usuais bases orgânicas nitrogenadas como direcionadores de estrutura. As sementes foram sintetizadas pelo método hidrotérmico empregando n-butilamina como direcionador de estrutura. Utilizando as sementes e o etanol, como codirecionador, a síntese de ZSM-5 foi realizada, tendo, como fonte de sílica, cinza de casca de arroz e, como fonte de alumínio, caul...

  16. Oxy-fuel combustion of solid fuels

    DEFF Research Database (Denmark)

    Toftegaard, Maja Bøg; Brix, Jacob; Jensen, Peter Arendt

    2010-01-01

    Oxy-fuel combustion is suggested as one of the possible, promising technologies for capturing CO2 from power plants. The concept of oxy-fuel combustion is removal of nitrogen from the oxidizer to carry out the combustion process in oxygen and, in most concepts, recycled flue gas to lower the flame...... provide additional options for improvement of process economics are however likewise investigated. Of particular interest is the change of the combustion process induced by the exchange of carbon dioxide and water vapor for nitrogen as diluent. This paper reviews the published knowledge on the oxy......-fuel process and focuses particularly on the combustion fundamentals, i.e. flame temperatures and heat transfer, ignition and burnout, emissions, and fly ash characteristics. Knowledge is currently available regarding both an entire oxy-fuel power plant and the combustion fundamentals. However, several...

  17. Pollutant Formation in Monodisperse Fuel Spray Combustion

    Science.gov (United States)

    Cernansky, N. P.; Sarv, H.

    1983-01-01

    The combustion of liquid sprays represents an extremely important class of combustion processes. In the transition region, encompassing droplet sizes in the range of 25-80 micron diameter, the mixing and evaporation processes are both incomplete at the flame front and burning occurs in a combined diffusive and premixed fashion. Under these conditions, the relative importance of heterogeneous and homogeneous effects in dominating the combustion process is switched and gives rise to a number of interesting phenomena. NO (sub x) formation in monodisperse spray combustion was investigated with the following specific objectives: (1) to quantitatively determine the effect of droplet size, number density, etc. on NO sub x formation in monodisperse fuel spray combustion; and (2) to isolate the important physical and chemical phenomena in NO sub x formation in these combustion systems.

  18. Sandia Combustion Research Program: Annual report, 1986

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    This report presents research results of the past year, divided thematically into some ten categories. Publications and presentations arising from this work are included in the appendix. Our highlighted accomplishment of the year is the announcement of the discovery and demonstration of the RAPRENOx process. This new mechanism for the elimination of nitrogen oxides from essentially all kinds of combustion exhausts shows promise for commercialization, and may eventually make a significant contribution to our nation's ability to control smog and acid rain. The sections of this volume describe the facility's laser and computer system, laser diagnostics of flames, combustion chemistry, reacting flows, liquid and solid propellant combustion, mathematical models of combustion, high-temperature material interfaces, studies of engine/furnace combustion, coal combustion, and the means of encouraging technology transfer. 182 refs., 170 figs., 12 tabs.

  19. Combustion and Heat Transfer Studies Utilizing Advanced Diagnostics: Combustion Studies

    Science.gov (United States)

    1992-11-01

    Also, m ass conservation balance in the plane of th 1.0 . ./Id -005 0- bluff body base provided an additional cross-check against (W/Uei U/a...jet than asa thick jet spreading into adump combustor. Ass a . NAlI 2’A.. , 2.0 L K consequence, in Fig. 5b. streamlines around die recirculatiofi zone...Combustio of 23. Rawe., It, and Kremer, H.: EWmtwa Spwsposm IfWhucabon Fucks wih Air NACA Rept. 1300,29M. (nternational) on Combustion, p.667, The

  20. Experimental research on combustion fluorine retention using calcium-based sorbets during coal combustion (I)

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Qing-jie; Lin, Zhi-yan; Liu, Jian-zhong; Wu, Xian; Zhou, Jun-hu; Cen, Ke-fa [Liaoning Technical University, Fuxin (China). College of Resource and Environment Engineering

    2008-06-15

    In order to provide experimental guide to commercial use of fluorine pollution control during coal combustion, with fluorine pollution control during coal combustion in mind, this paper proposed the theory of combustion fluorine retention technology. Feasibility of fluorine retention reaction with calcium-based fluorine retention agent was analyzed through thermodynamic calculation during coal combustion. By simulating the restraining and retention effects and influential factors of calcium-based sorbets on vaporized fluoride during experimental combustion using fixed bed tube furnace, the paper systematically explored the influential law of such factors as combustion temperature, retention time, and added quantities of calcium-based sorbets on effects of fluorine retention. The research result shows that adding calcium-based fluorine retention agent in coal combustion has double effects of fluorine retention and sulfur retention, it lays an experimental foundation for commercial test of combustion fluorine retention. 7 refs., 2 figs., 4 tabs.

  1. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, NOX CONTROL TECHNOLOGIES, CATALYTICA COMBUSTION SYSTEMS, INC., XONON FLAMELESS COMBUSTION SYSTEM

    Science.gov (United States)

    The Environmental Technology Verification report discusses the technology and performance of the Xonon Cool Combustion System manufactured by Catalytica Energy Systems, Inc., formerly Catalytica Combustion Systems, Inc., to control NOx emissions from gas turbines that operate wit...

  2. The combustion of solid fuels and wastes

    CERN Document Server

    Tillman, David

    1991-01-01

    Careful organization and empirical correlations help clarify the prodigious technical information presented in this useful reference.Key Features* Written for practicing engineers, this comprehensive book supplies an overall framework of the combustion process; It connects information on specific reactions and reaction sequences with current applications and hardware; Each major group of combustion solids is evaluated; Among the many topics covered are:* Various biomass forms* The coalification process* Grate, kiln, and suspension firing* Fluidized bed combustion

  3. Materials for High-Temperature Catalytic Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Ersson, Anders

    2003-04-01

    Catalytic combustion is an environmentally friendly technique to combust fuels in e.g. gas turbines. Introducing a catalyst into the combustion chamber of a gas turbine allows combustion outside the normal flammability limits. Hence, the adiabatic flame temperature may be lowered below the threshold temperature for thermal NO{sub X} formation while maintaining a stable combustion. However, several challenges are connected to the application of catalytic combustion in gas turbines. The first part of this thesis reviews the use of catalytic combustion in gas turbines. The influence of the fuel has been studied and compared over different catalyst materials. The material section is divided into two parts. The first concerns bimetallic palladium catalysts. These catalysts showed a more stable activity compared to their pure palladium counterparts for methane combustion. This was verified both by using an annular reactor at ambient pressure and a pilot-scale reactor at elevated pressures and flows closely resembling the ones found in a gas turbine combustor. The second part concerns high-temperature materials, which may be used either as active or washcoat materials. A novel group of materials for catalysis, i.e. garnets, has been synthesised and tested in combustion of methane, a low-heating value gas and diesel fuel. The garnets showed some interesting abilities especially for combustion of low-heating value, LHV, gas. Two other materials were also studied, i.e. spinels and hexa aluminates, both showed very promising thermal stability and the substituted hexa aluminates also showed a good catalytic activity. Finally, deactivation of the catalyst materials was studied. In this part the sulphur poisoning of palladium, platinum and the above-mentioned complex metal oxides has been studied for combustion of a LHV gas. Platinum and surprisingly the garnet were least deactivated. Palladium was severely affected for methane combustion while the other washcoat materials were

  4. Strategy for intelligent internal combustion engine with homogenous combustion in cylinder

    OpenAIRE

    Weclas, Miroslaw

    2009-01-01

    In this report the author proposes strategy for development of intelligent combustion systems with a goal to approach a near-zero emission internal combustion engine operating in a wide range of speeds and loads. Main requirement for future I.C. engine is to develop a system permitting homogeneous combustion process (minimum of engine emissions) under all operational conditions. The author suggests, that none existing individual combustion system may satisfy these conditions. However, combina...

  5. Selection of technology for the low calorific synthetic gas combustion in the gas turbine combustion chamber

    Science.gov (United States)

    Filippov, Prokopy; Levin, Evgeny; Ryzhkov, Alexander

    2017-10-01

    The leading gas turbines manufacturers are developing the technologies of the environmental friendly combustion of industrial and synthetic gases of low calorific values. In this case they are faced with critical problems concerning combustion stability assurance and the necessity of the gas turbines significant modernization due to the differences between the low calorific and natural gases. The numerical simulation results of the low calorific value synthetic gas combustion in the combustion chamber by means of different technologies are considered in the paper.

  6. Supercritical Combustion of Liquid Oxygen and Hydrocarbon for Staged-Combustion Cycle Engine Technology Development

    Science.gov (United States)

    2009-06-30

    Mixtures," by G. Ribert, N. Zong, V. Yang, L. Pons , N. Darabiha, and S. Candel, Combustion and Flame, Vol. 154, 2008, pp. 319-330. 3. "Mass Transfer...and Combustion in Transcritical Non-Premixed Counterflows," by L. Pons , N. Darabiha, S. Candel, G. Ribert, and V. Yang, Combustion Theory and...supercritical environment," Combust. Sci. Tech. 178, 193 (2006). T. Poinsot and S. Lele , "Boundary conditions for direct simulation of compressible viscous

  7. Pyrolysis reactor and fluidized bed combustion chamber

    Science.gov (United States)

    Green, Norman W.

    1981-01-06

    A solid carbonaceous material is pyrolyzed in a descending flow pyrolysis reactor in the presence of a particulate source of heat to yield a particulate carbon containing solid residue. The particulate source of heat is obtained by educting with a gaseous source of oxygen the particulate carbon containing solid residue from a fluidized bed into a first combustion zone coupled to a second combustion zone. A source of oxygen is introduced into the second combustion zone to oxidize carbon monoxide formed in the first combustion zone to heat the solid residue to the temperature of the particulate source of heat.

  8. Fuel gas combustion research at METC

    Energy Technology Data Exchange (ETDEWEB)

    Norton, T.S.

    1995-06-01

    The in-house combustion research program at METC is an integral part of many METC activities, providing support to METC product teams, project managers, and external industrial and university partners. While the majority of in-house combustion research in recent years has been focussed on the lean premixed combustion of natural gas fuel for Advanced Turbine Systems (ATS) applications, increasing emphasis is being placed on issues of syngas combustion, as the time approaches when the ATS and coal-fired power systems programs will reach convergence. When the METC syngas generator is built in 1996, METC will have the unique combination of mid-scale pressurized experimental facilities, a continuous syngas supply with variable ammonia loading, and a team of people with expertise in low-emissions combustion, chemical kinetics, combustion modeling, combustion diagnostics, and the control of combustion instabilities. These will enable us to investigate such issues as the effects of pressure, temperature, and fuel gas composition on the rate of conversion of fuel nitrogen to NOx, and on combustion instabilities in a variety of combustor designs.

  9. Pulsed atmospheric fluidized bed combustion

    Energy Technology Data Exchange (ETDEWEB)

    1989-11-01

    In order to verify the technical feasibility of the MTCI Pulsed Atmospheric Fluidized Bed Combustor technology, a laboratory-scale system was designed, built and tested. Important aspects of the operational and performance parameters of the system were established experimentally. A considerable amount of the effort was invested in the initial task of constructing an AFBC that would represent a reasonable baseline against which the performance of the PAFBC could be compared. A summary comparison of the performance and emissions data from the MTCI 2 ft {times} 2 ft facility (AFBC and PAFBC modes) with those from conventional BFBC (taller freeboard and recycle operation) and circulating fluidized bed combustion (CFBC) units is given in Table ES-1. The comparison is for typical high-volatile bituminous coals and sorbents of average reactivity. The values indicated for BFBC and CFBC were based on published information. The AFBC unit that was designed to act as a baseline for the comparison was indeed representative of the larger units even at the smaller scale for which it was designed. The PAFBC mode exhibited superior performance in relation to the AFBC mode. The higher combustion efficiency translates into reduced coal consumption and lower system operating cost; the improvement in sulfur capture implies less sorbent requirement and waste generation and in turn lower operating cost; lower NO{sub x} and CO emissions mean ease of site permitting; and greater steam-generation rate translates into less heat exchange surface area and reduced capital cost. Also, the PAFBC performance generally surpasses those of conventional BFBC, is comparable to CFBC in combustion and NO{sub x} emissions, and is better than CFBC in sulfur capture and CO emissions even at the scaled-down size used for the experimental feasibility tests.

  10. High pressure optical combustion probe

    Energy Technology Data Exchange (ETDEWEB)

    Woodruff, S.D.; Richards, G.A.

    1995-06-01

    The Department of Energy`s Morgantown Energy Technology Center has developed a combustion probe for monitoring flame presence and heat release. The technology involved is a compact optical detector of the OH radical`s UV fluorescence. The OH Monitor/Probe is designed to determine the flame presence and provide a qualitative signal proportional to the flame intensity. The probe can be adjusted to monitor a specific volume in the combustion zone to track spatial fluctuations in the flame. The probe is capable of nanosecond time response and is usually slowed electronically to fit the flame characteristics. The probe is a sapphire rod in a stainless steel tube which may be inserted into the combustion chamber and pointed at the flame zone. The end of the sapphire rod is retracted into the SS tube to define a narrow optical collection cone. The collection cone may be adjusted to fit the experiment. The fluorescence signal is collected by the sapphire rod and transmitted through a UV transmitting, fused silica, fiber optic to the detector assembly. The detector is a side window photomultiplier (PMT) with a 310 run line filter. A Hamamatsu photomultiplier base combined with a integral high voltage power supply permits this to be a low voltage device. Electronic connections include: a power lead from a modular DC power supply for 15 VDC; a control lead for 0-1 volts to control the high voltage level (and therefore gain); and a lead out for the actual signal. All low voltage connections make this a safe and easy to use device while still delivering the sensitivity required.

  11. Theoretical studies of combustion dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, J.M. [Emory Univ., Atlanta, GA (United States)

    1993-12-01

    The basic objectives of this research program are to develop and apply theoretical techniques to fundamental dynamical processes of importance in gas-phase combustion. There are two major areas currently supported by this grant. One is reactive scattering of diatom-diatom systems, and the other is the dynamics of complex formation and decay based on L{sup 2} methods. In all of these studies, the authors focus on systems that are of interest experimentally, and for which potential energy surfaces based, at least in part, on ab initio calculations are available.

  12. Leaching from biomass combustion ash

    DEFF Research Database (Denmark)

    Maresca, Alberto; Astrup, Thomas Fruergaard

    2014-01-01

    The use of biomass combustion ashes for fertilizing and liming purposes has been widely addressed in scientific literature. Nevertheless, the content of potentially toxic compounds raises concerns for a possible contamination of the soil. During this study five ash samples generated at four...... in water. The content of the selected heavy metals (i.e. Cr, Ni, Pb and Cd) complied with the Danish Statutory Order on the use of bio-ash for agricultural purposes; however, critical releases of Cr were detected in the leachate extracts, especially in the fly ash. High alkaline pHs were measured in all...

  13. Transient combustion in hybrid rockets

    Science.gov (United States)

    Karabeyoglu, Mustafa Arif

    1998-09-01

    Hybrid rockets regained interest recently as an alternative chemical propulsion system due to their advantages over the solid and liquid systems that are currently in use. Development efforts on hybrids revealed two important problem areas: (1) low frequency instabilities and (2) slow transient response. Both of these are closely related to the transient behavior which is a poorly understood aspect of hybrid operation. This thesis is mainly involved with a theoretical study of transient combustion in hybrid rockets. We follow the methodology of identifying and modeling the subsystems of the motor such as the thermal lags in the solid, boundary layer combustion and chamber gasdynamics from a dynamic point of view. We begin with the thermal lag in the solid which yield the regression rate for any given wall heat flux variation. Interesting phenomena such as overshooting during throttling and the amplification and phase lead regions in the frequency domain are discovered. Later we develop a quasi-steady transient hybrid combustion model supported with time delays for the boundary layer processes. This is integrated with the thermal lag system to obtain the thermal combustion (TC) coupled response. The TC coupled system with positive delays generated low frequency instabilities. The scaling of the instabilities are in good agreement with actual motor test data. Finally, we formulate a gasdynamic model for the hybrid chamber which successfully resolves the filling/emptying and longitudinal acoustic behavior of the motor. The TC coupled system is later integrated to the gasdynamic model to obtain the overall response (TCG coupled system) of gaseous oxidizer motors with stiff feed systems. Low frequency instabilities were also encountered for the TCG coupled system. Apart from the transient investigations, the regression rate behavior of liquefying hybrid propellants such as solid cryogenic materials are also studied. The theory is based on the possibility of enhancement

  14. Buoyancy effects on smoldering combustion

    Science.gov (United States)

    Dosanjh, S.; Peterson, J.; Fernandez-Pello, A. C.; Pagni, P. J.

    1985-01-01

    The effect of buoyancy on the rate of spread of a concurrent smolder reaction through a porous combustible material is investigated theoretically and experimentally. In the experiments, buoyant forces are controlled by varying the density difference, and the smolder rate spread through porous alpha cellulose (0.83 void fraction) is measured as a function of the ambient air pressure. The smolder velocity is found to increase with the ambient pressure; extinction occurs when the buoyancy forces cannot overcome the drag forces, indicating that diffusion by itself cannot support the spread of a smolder reaction. Theoretical predictions are found to be in good qualitative agreement with the experimental results.

  15. COMBUSTION PROPERTIES OF EUCALYPTUS WOOD

    Directory of Open Access Journals (Sweden)

    Yalçın ÖRS

    1999-03-01

    Full Text Available In this study, the combustion properties of some impregnation materials (abiotic and biotic factors used for eucalyptus wood in interior or exterior environments were investigated. The experimental samples were prepared from Eucalyptus wood based on ASTM-D-1413-76 Tanalith-CBC, boric acid, borax, vacsol-WR, immersol-WR, polyethylen glycole-400 and ammonium sulphate were used as an impregnation material. The results indicated that, vacuum treatment on Eucalyptus gave the lowest retention value of salts. Compounds containing boron+salt increased fire resistance however water repellents decreased the wood flammability.

  16. Creación de un videojuego de realidad virtual utilizando Unreal Engine 4

    OpenAIRE

    Muñoz Periñán, José Luis

    2017-01-01

    Creación de un videojuego de realidad virtual compatible con Oculus Rift, utilizando Unreal Engine 4. El género del videojuego será el de un videojuego de terror que aproveche las ventajas de la realidad virtual.

  17. Combustion

    National Research Council Canada - National Science Library

    Glassman, Irvin

    1996-01-01

    ... permission in writing from the publisher. Permissions may be sought directly from Elsevier's Science and Technology Rights Department in Oxford, UK. Phone (44) 1865 843830, Fax: (44) 1865 853333, e-mail: permissions@elsevier.co.uk. You may also complete your request on-line via the Elsevier homepage: http://www.elsevier.com by selecting "...

  18. Measurement and analysis of combustion response to transverse combustion instability

    Science.gov (United States)

    Pomeroy, Brian R.

    This research aimed to gain a better understanding of the response of a gas-centered swirl coaxial injector to transverse combustion instability. The goals of the research were to develop a combustion chamber that would be able to spontaneously produce transverse combustion instability at elevated pressures and temperatures. Methods were also developed to analyze high-speed video images to understand the response of the injector. A combustion chamber was designed that produced high levels of instabilities. The chamber was capable of pressures as high as 1034 kPa (150 psi) and operated using decomposed 90% hydrogen peroxide and JP-8. The chamber used an array of seven gas-centered swirl coaxial injectors that exhibited linear instability to drive the transverse oscillations. The injector elements would operate in a monopropellant configuration flowing only decomposed hydrogen peroxide or in a bipropellant configuration. The location of the bipropellant injectors could be varied to change the level of the instability in the chamber from 10% of the chamber pressure up to 70% of the chamber pressure. A study element was placed in the center of the chamber where it was observed simultaneously by two high-speed video cameras which recorded a backlit video to show the location of the fuel spray and the location of the emitted CH* chemiluminescence. The videos were synchronized with high frequency pressure measurements to gain a full understanding of the physics in the combustion chamber. Results showed that the study element was coupled with the first mode velocity wave. This was expected due to the first mode velocity anti-node being located in the center of the chamber. The velocity is an absolute maximum twice during each cycle so the coupling with the second mode pressure was also investigated showing a possible coupling with both the velocity and pressure. The results of the first mode velocity showed that, as the velocity wave traveled through the chamber, the fuel

  19. Combustion chemistry and formation of pollutants; Chimie de la combustion et formation des polluants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This book of proceedings reports on 7 papers on combustion chemistry and formation of pollutants presented during the workshop organized by the `Combustion and Flames` section of the French society of thermal engineers. The chemistry of combustion is analyzed in various situations such as: turbojet engines, spark ignition engines, industrial burners, gas turbines etc... Numerical simulation is used to understand the physico-chemical processes involved in combustion, to describe the kinetics of oxidation, combustion and flame propagation, and to predict the formation of pollutants. (J.S.)

  20. Variable stroke internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Roseby, B.; Hallman, E.P.

    1979-11-20

    An internal combustion engine is described in which the longitudinal center line of the cylinders are parallel to and equally spaced around the longitudinal center line of the engine. The pistons, working within said cylinders, are mounted on a swash plate mechanism, by means of which the reciprocating motion the pistons is translated into the rotary motion of a carrier plate to which the said swash plate is mounted and, from which, is taken the drive into the vehicle transmission. Said swash plate is mounted on a post at the circumference of the carrier plate and pivots around said post when moved, on a longitudinal axis, by a mechanism. As each piston, in turn, passes the point on the swashplate adjacent to the mounting post, it is at the top-dead-center position in its cylinder. As said piston passes the diametrically opposite point on the swash plate it is at the bottom-dead-center position. When the swash plate angle is changed, by moving said mechanism, the bottom dead center position is changed thus causing the stroke of the piston to be changed. A circular form cylinder head contains a combustion chamber for each cylinder and a disc, driven by a forward projecting shaft mounted on the carrier plate, through gearing, and having cam forms on the face actuates the valve mechanism to cause the inlet and exhaust gases to flow to and from the cylinders as required for operation of the running cycle.

  1. Studies on thermoelectric power generation consuming municipal solid waste (MSW) and using bubbling fluidized bed gasifier : Estudos em geração termelétrica a partir de resíduos sólidos urbanos (RSU) utilizando gaseificadores de leito fluidizado borbulhante

    OpenAIRE

    Andres Felipe Rodriguez Torres

    2016-01-01

    Resumo: O presente trabalho introduz novos desenvolvimentos da estratégia no conceito Fuel-Slurry Integrated Gasifier/Gas Turbine para a geração de potência termoelétrica aplicada ao caso de Resíduos Sólidos Urbanos (RSU). O processo FSIG/GT permite a alimentação do combustível num gaseificador pressurizado utilizando bombas de lama disponíveis no mercado, evitando a necessidade de sistemas de silos em cascata. O gaseificador opera em regime de Leito Fluidizado Borbulhante (Bubbling Fluidized...

  2. Thermally stimulated luminescence studies in combustion ...

    Indian Academy of Sciences (India)

    Synthesis of materials by combustion technique results in homogeneous and fine crystalline product. Further, the technique became more popular since it not only saved time and energy but also was easy to process. Aluminum oxide phosphor was synthesized by using urea as fuel in combustion reaction.

  3. 30 CFR 57.4104 - Combustible waste.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Combustible waste. 57.4104 Section 57.4104... Control Prohibitions/precautions/housekeeping § 57.4104 Combustible waste. (a) Waste materials, including liquids, shall not accumulate in quantities that could create a fire hazard. (b) Waste or rags containing...

  4. Sandia combustion research program: Annual report, 1987

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, R.E.; Sanders, B.R.; Ivanetich, C.A. (eds.)

    1988-01-01

    More than a decade ago, in response to a national energy crisis, Sandia proposed to the US Department of Energy a new, ambitious program in combustion research. Our strategy was to apply the rapidly increasing capabilities in lasers and computers to combustion science and technology. Shortly thereafter, the Combustion Research Facility (CRF) was established at Sandia's Livermore location. Designated a ''User Facility,'' the charter of the CRF was to develop and maintain special-purpose resources to support a nationwide initiative--involving US universities, industry, and national laboratories--to improve our understanding and control of combustion. This report includes descriptions of several research projects which have been stimulated by Working Groups and involve the on-site participation of industry scientists. DOE's Industry Technology Fellowship Program has been instrumental in the success of some of the joint efforts. The remainder of this report presents research results of calendar year 1987, separated thematically into nine categories. Refereed journal articles appearing in print during 1987, along with selected other publications, are included at the end of Section 10. In addition to our ''traditional'' research--chemistry, reacting flow, diagnostics, engine combustion, and coal combustion--you will note continued progress in somewhat recent themes: pulse combustion, high temperature materials, and energetic materials, for example. Moreover, we have just started a small, new effort to understand combustion-related issues in the management of toxic and hazardous materials.

  5. Internal combustion engines in hybrid vehicles

    NARCIS (Netherlands)

    Mourad, S.; Weijer, C.J.T. van de; Beckman, D.E.

    1998-01-01

    In this paper the use of internal combustion engines in hybrid powertrains is investigated. The substantial difference between the use of internal combustion engines in conventional and in hybrid vehicles mean that engines for hybrid vehicles should be designed specifically for the purpose. At the

  6. Injector tip for an internal combustion engine

    Science.gov (United States)

    Shyu, Tsu Pin; Ye, Wen

    2003-05-20

    This invention relates to a the tip structure of a fuel injector as used in a internal combustion engine. Internal combustion engines using Homogeneous Charge Compression Ignition (HCCI) technology require a tip structure that directs fuel spray in a downward direction. This requirement necessitates a tip design that is capable of withstanding mechanical stresses associated with the design.

  7. Coal slurry combustion and technology. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    Volume II contains papers presented at the following sessions of the Coal Slurry Combustion and Technology Symposium: (1) bench-scale testing; (2) pilot testing; (3) combustion; and (4) rheology and characterization. Thirty-three papers have been processed for inclusion in the Energy Data Base. (ATT)

  8. A model for premixed combustion oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Janus, M.C.; Richards, G.A.

    1996-09-01

    This paper describes a simulation based on a time dependent, nonlinear control volume analysis. The combustion is modeled as a well-stirred reactor having finite kinetics. Flow properties and species in the nozzle, combustion, and tailpipe regions are determined using a control volume formulation of the conservation equation.

  9. Combustion synthesis and photoluminescence study of silicate ...

    Indian Academy of Sciences (India)

    Silicate based bioceramics are promising candidates as biomaterials for tissue engineering. The combustion synthesis method provides control on the morphology and particle size of the synthesized material. This paper discusses the combustion synthesis of akermanite (Ca2MgSi2O7 and Sr2MgSi2O7), which has been ...

  10. A predictive model of natural gas mixture combustion in internal combustion engines

    Directory of Open Access Journals (Sweden)

    Henry Espinoza

    2007-05-01

    Full Text Available This study shows the development of a predictive natural gas mixture combustion model for conventional com-bustion (ignition engines. The model was based on resolving two areas; one having unburned combustion mixture and another having combustion products. Energy and matter conservation equations were solved for each crankshaft turn angle for each area. Nonlinear differential equations for each phase’s energy (considering compression, combustion and expansion were solved by applying the fourth-order Runge-Kutta method. The model also enabled studying different natural gas components’ composition and evaluating combustion in the presence of dry and humid air. Validation results are shown with experimental data, demonstrating the software’s precision and accuracy in the results so produced. The results showed cylinder pressure, unburned and burned mixture temperature, burned mass fraction and combustion reaction heat for the engine being modelled using a natural gas mixture.

  11. A predictive model of natural gas mixture combustion in internal combustion engines

    Directory of Open Access Journals (Sweden)

    Henry Espinoza

    2010-04-01

    Full Text Available This study shows the development of a predictive natural gas mixture combustion model for conventional com-bustion (ignition engines. The model was based on resolving two areas; one having unburned combustion mixture and another having combustion products. Energy and matter conservation equations were solved for each crankshaft turn angle for each area. Nonlinear differential equations for each phase’s energy (considering compression, combustion and expansion were solved by applying the fourth-order Runge-Kutta method. The model also enabled studying different natural gas components’ composition and evaluating combustion in the presence of dry and humid air. Validation results are shown with experimental data, demonstrating the software’s precision and accuracy in the results so produced. The results showed cylinder pressure, unburned and burned mixture temperature, burned mass fraction and combustion reaction heat for the engine being modelled using a natural gas mixture.

  12. Internal and surface phenomena in metal combustion

    Science.gov (United States)

    Dreizin, Edward L.; Molodetsky, Irina E.; Law, Chung K.

    1995-01-01

    Combustion of metals has been widely studied in the past, primarily because of their high oxidation enthalpies. A general understanding of metal combustion has been developed based on the recognition of the existence of both vapor-phase and surface reactions and involvement of the reaction products in the ensuing heterogeneous combustion. However, distinct features often observed in metal particle combustion, such as brightness oscillations and jumps (spearpoints), disruptive burning, and non-symmetric flames are not currently understood. Recent metal combustion experiments using uniform high-temperature metal droplets produced by a novel micro-arc technique have indicated that oxygen dissolves in the interior of burning particles of certain metals and that the subsequent transformations of the metal-oxygen solutions into stoichiometric oxides are accompanied with sufficient heat release to cause observed brightness and temperature jumps. Similar oxygen dissolution has been observed in recent experiments on bulk iron combustion but has not been associated with such dramatic effects. This research addresses heterogeneous metal droplet combustion, specifically focusing on oxygen penetration into the burning metal droplets, and its influence on the metal combustion rate, temperature history, and disruptive burning. A unique feature of the experimental approach is the combination of the microgravity environment with a novel micro-arc Generator of Monodispersed Metal Droplets (GEMMED), ensuring repeatable formation and ignition of uniform metal droplets with controllable initial temperature and velocity. The droplet initial temperatures can be adjusted within a wide range from just above the metal melting point, which provides means to ignite droplets instantly upon entering an oxygen containing environment. Initial droplet velocity will be set equal to zero allowing one to organize metal combustion microgravity experiments in a fashion similar to usual microgravity

  13. Time Resolved Measurements and Reactive Pathways of Hypergolic Bipropellant Combustion

    National Research Council Canada - National Science Library

    Smith, Jr, James E

    2006-01-01

    This research has improved the fundamental understanding of the physical mechanisms leading to the ignition and combustion of hypergolic propellants from high-speed visualization and combustion diagnostics...

  14. Some characteristics of fine beryllium particle combustion

    Science.gov (United States)

    Davydov, D. A.; Kholopova, O. V.; Kolbasov, B. N.

    2007-08-01

    Beryllium dust will be produced under plasma interaction with beryllium armor of the first wall in ITER. Exothermal reaction of this dust with water steam or air, which can leak into the reactor vacuum chamber in some accidents, gives concern in respect to reactor safety. Results of studies devoted to combustion of fine beryllium particles are reviewed in the paper. A chemically active medium and elevated temperature are prerequisite to the combustion of beryllium particles. Their ignition is hampered by oxide films, which form a diffusion barrier on the particle surface as a result of pre-flame oxidation. The temperature to initiate combustion of particles depends on flame temperature, particle size, composition of combustible mixture, heating rate and other factors. In mixtures enriched with combustible, the flame temperature necessary to ignite individual particles approaches the beryllium boiling temperature.

  15. 2003 Laser Diagnostic in Combustion Conference

    Energy Technology Data Exchange (ETDEWEB)

    Mark G. Allen

    2004-09-10

    The GRC Laser Diagnostics in Combustion aims at bringing together scientists and engineers working in the front edge of research and development to discuss and find new ways to solve problems connected to combustion diagnostics. Laser-based techniques have proven to be very efficient tools for studying combustion processes thanks to features as non-intrusiveness in combination with high spatial and temporal resolution. Major tasks for the community are to develop and apply techniques for quantitative measurements with high precision e.g of species concentrations, temperatures, velocities and particles characteristics (size and concentration). These issues are of global interest, considering that the major part of the World's energy conversion comes from combustion sources and the influence combustion processes have on the environment and society.

  16. Interactive wood combustion for botanical tree models

    KAUST Repository

    Pirk, Sören

    2017-11-22

    We present a novel method for the combustion of botanical tree models. Tree models are represented as connected particles for the branching structure and a polygonal surface mesh for the combustion. Each particle stores biological and physical attributes that drive the kinetic behavior of a plant and the exothermic reaction of the combustion. Coupled with realistic physics for rods, the particles enable dynamic branch motions. We model material properties, such as moisture and charring behavior, and associate them with individual particles. The combustion is efficiently processed in the surface domain of the tree model on a polygonal mesh. A user can dynamically interact with the model by initiating fires and by inducing stress on branches. The flames realistically propagate through the tree model by consuming the available resources. Our method runs at interactive rates and supports multiple tree instances in parallel. We demonstrate the effectiveness of our approach through numerous examples and evaluate its plausibility against the combustion of real wood samples.

  17. Combustion Engines Development Mixture Formation, Combustion, Emissions and Simulation

    CERN Document Server

    Schwarz, Christian; Teichmann, Rüdiger

    2012-01-01

    In the development of engines and vehicles it is nowadays standard practice to use commercially available computing programmes for simulation, not only of the transient reaction of vehicles or of the complete driveshaft, but also of the highly unsteady processes in the combustion chamber of an engine. Normally the source code is not available for these computing programmes and it takes too much time to study the respective specifications, so the users often do not have sufficient knowledge about the physical and chemical contents of the approaches that the programmes are based on. We have often been faced with this fact in talks to employees or in discussions during the presentation of results of simulation. Therefore it is our aim to point out different physical and chemical approaches and to show the possibilities and limits of the models used.

  18. Distributed combustion in a cyclonic burner

    Science.gov (United States)

    Sorrentino, Giancarlo; Sabia, Pino; de Joannon, Mara; Cavaliere, Antonio; Ragucci, Raffaele

    2017-11-01

    Distributed combustion regime occurs in several combustion technologies were efficient and environmentally cleaner energy conversion are primary tasks. For such technologies (MILD, LTC, etc…), working temperatures are enough low to boost the formation of several classes of pollutants, such as NOx and soot. To access this temperature range, a significant dilution as well as preheating of reactants is required. Such conditions are usually achieved by a strong recirculation of exhaust gases that simultaneously dilute and pre-heat the fresh reactants. However, the intersection of low combustion temperatures and highly diluted mixtures with intense pre-heating alters the evolution of the combustion process with respect to traditional flames, leading to significant features such as uniformity and distributed ignition. The present study numerically characterized the turbulence-chemistry and combustion regimes of propane/oxygen mixtures, highly diluted in nitrogen, at atmospheric pressure, in a cyclonic combustor under MILD Combustion operating conditions. The velocity and mixing fields were obtained using CFD with focus on mean and fluctuating quantities. The flow-field information helped differentiate between the impact of turbulence levels and dilution ones. The integral length scale along with the fluctuating velocity is critical to determine Damköhler and Karlovitz numbers. Together these numbers identify the combustion regime at which the combustor is operating. This information clearly distinguishes between conventional flames and distributed combustion. The results revealed that major controllers of the reaction regime are dilution and mixing levels; both are significantly impacted by lowering oxygen concentration through entrainment of hot reactive species from within the combustor, which is important in distributed combustion. Understanding the controlling factors of distributed regime is critical for the development and deployment of these novel combustion

  19. Indirect combustion noise of auxiliary power units

    Science.gov (United States)

    Tam, Christopher K. W.; Parrish, Sarah A.; Xu, Jun; Schuster, Bill

    2013-08-01

    Recent advances in noise suppression technology have significantly reduced jet and fan noise from commercial jet engines. This leads many investigators in the aeroacoustics community to suggest that core noise could well be the next aircraft noise barrier. Core noise consists of turbine noise and combustion noise. There is direct combustion noise generated by the combustion processes, and there is indirect combustion noise generated by the passage of combustion hot spots, or entropy waves, through constrictions in an engine. The present work focuses on indirect combustion noise. Indirect combustion noise has now been found in laboratory experiments. The primary objective of this work is to investigate whether indirect combustion noise is also generated in jet and other engines. In a jet engine, there are numerous noise sources. This makes the identification of indirect combustion noise a formidable task. Here, our effort concentrates exclusively on auxiliary power units (APUs). This choice is motivated by the fact that APUs are relatively simple engines with only a few noise sources. It is, therefore, expected that the chance of success is higher. Accordingly, a theoretical model study of the generation of indirect combustion noise in an Auxiliary Power Unit (APU) is carried out. The cross-sectional areas of an APU from the combustor to the turbine exit are scaled off to form an equivalent nozzle. A principal function of a turbine in an APU is to extract mechanical energy from the flow stream through the exertion of a resistive force. Therefore, the turbine is modeled by adding a negative body force to the momentum equation. This model is used to predict the ranges of frequencies over which there is a high probability for indirect combustion noise generation. Experimental spectra of internal pressure fluctuations and far-field noise of an RE220 APU are examined to identify anomalous peaks. These peaks are possible indirection combustion noise. In the case of the

  20. Filtration Combustion in Smoldering and SHS

    Science.gov (United States)

    Matkowsky, Bernard J.

    2001-01-01

    Smolder waves and SHS (self-propagating high-temperature synthesis) waves are both examples of filtration combustion waves propagating in porous media. Smoldering combustion is important for the study of fire safety. Smoldering itself can cause damage, its products are toxic and it can also lead to the more dangerous gas phase combustion which corresponds to faster propagation at higher temperatures. In SHS , a porous solid sample, consisting of a finely ground powder mixture of reactants, is ignited at one end. A high temperature thermal wave, having a frontal structure, then propagates through the sample converting reactants to products. The SHS technology appears to enjoy a number of advantages over the conventional technology, in which the sample is placed in a furnace and "baked" until it is "well done". The advantages include shorter synthesis times, greater economy, in that the internal energy of the reactions is employed rather than the costly external energy of the furnace, purer products, simpler equipment and no intrinsic limitation on the size of the sample to be synthesized as exists in the conventional technology. When delivery of reactants through the pores to the reaction site is an important aspect of the combustion process, it is referred to as filtration combustion. The two types of filtration combustion have a similar mathematical formulation, describing the ignition, propagation and extinction of combustion waves in porous media. The goal in each case, however, is different. In smoldering the desired goal is to prevent propagation, whereas in SHS the goal is to ensure propagation of the combustion wave, leading to the synthesis of desired products. In addition, the scales in the two areas of application differ. Smoldering generally occurs at lower temperatures and propagation velocities than in SHS nevertheless, the two applications have much in common so that what is learned fit make application can be used to advantage in the other. In porous

  1. Custo da eletricidade gerada em conjunto motor gerador utilizando biogás da suinocultura - DOI: 10.4025/actascitechnol.v26i2.1510

    Directory of Open Access Journals (Sweden)

    Samuel Nelson Melegari de Souza

    2004-03-01

    Full Text Available Uma das maiores fontes de energia disponíveis nas áreas rurais e agroindustriais é a biomassa. A mesma aparece na forma de resíduos vegetais e animais, tais como restos de colheita, esterco animal, plantações energéticas e efluentes agroindustriais. Estes resíduos podem ser utilizados pelo produtor rural ou agroindústria para a queima direta, visando a produção de calor ou produção de biogás em biodigestores. Nas propriedades agrícolas, onde há a atividade de suinocultura, ocorre a disponibilidade desses resíduos, caracterizando-se num grande potencial energético. No presente trabalho objetivou-se determinar o custo e viabilidade de produção de eletricidade gerada a partir do biogás EM uma propriedade rural, utilizando-se como equipamentos de conversão de biogás em eletricidade, um motor de combustão interna acoplado a um gerador elétrico

  2. Basic Aerodynamics of Combustion Chambers,

    Science.gov (United States)

    1981-05-20

    n layer, an- its rhti re ai ei ar td . te II- to vortical wraXes which are also cplled "vo-tical rolls." r, and r,~=the er-temal 142 GaI M6.12 *%AAtM...8217-2XCC, UMn Th-~ t tr’.~t in ain~zttfror tecit vr’ 0 7 fij74,it ~r ~ h-t >2 h’’tof the jeb ,;p ~ ’ - ~~ *~~~k -. A--w.- - -- Chaptler 8 Tur~l.flftece Jet...G, is very small (the straight line AD), then, it is only possible to have combustion when one has temperature TD ; no other condition will do. If one

  3. Nanoparticle emissions from combustion engines

    CERN Document Server

    Merkisz, Jerzy

    2015-01-01

     This book focuses on particulate matter emissions produced by vehicles with combustion engines. It describes the physicochemical properties of the particulate matter, the mechanisms of its formation and its environmental impacts (including those on human beings). It discusses methods for measuring particulate mass and number, including the state-of-the-art in Portable Emission Measurement System (PEMS) equipment for measuring the exhaust emissions of both light and heavy-duty vehicles and buses under actual operating conditions. The book presents the authors’ latest investigations into the relations between particulate emission (mass and number) and engine operating parameters, as well as their new findings obtained through road tests performed on various types of vehicles, including those using diesel particulate filter regeneration. The book, which addresses the needs of academics and professionals alike, also discusses relevant European regulations on particulate emissions and highlights selected metho...

  4. Catalytic combustion of residual fuels

    Science.gov (United States)

    Bulzan, D. L.; Tacina, R. R.

    1981-01-01

    A noble metal catalytic reactor was tested using two grades of petroleum derived residual fuels at specified inlet air temperatures, pressures, and reference velocities. Combustion efficiencies greater than 99.5 percent were obtained. Steady state operation of the catalytic reactor required inlet air temperatures of at least 800 K. At lower inlet air temperatures, upstream burning in the premixing zone occurred which was probably caused by fuel deposition and accumulation on the premixing zone walls. Increasing the inlet air temperature prevented this occurrence. Both residual fuels contained about 0.5 percent nitrogen by weight. NO sub x emissions ranged from 50 to 110 ppm by volume at 15 percent excess O2. Conversion of fuel-bound nitrogen to NO sub x ranged from 25 to 50 percent.

  5. Extended lattice Boltzmann scheme for droplet combustion.

    Science.gov (United States)

    Ashna, Mostafa; Rahimian, Mohammad Hassan; Fakhari, Abbas

    2017-05-01

    The available lattice Boltzmann (LB) models for combustion or phase change are focused on either single-phase flow combustion or two-phase flow with evaporation assuming a constant density for both liquid and gas phases. To pave the way towards simulation of spray combustion, we propose a two-phase LB method for modeling combustion of liquid fuel droplets. We develop an LB scheme to model phase change and combustion by taking into account the density variation in the gas phase and accounting for the chemical reaction based on the Cahn-Hilliard free-energy approach. Evaporation of liquid fuel is modeled by adding a source term, which is due to the divergence of the velocity field being nontrivial, in the continuity equation. The low-Mach-number approximation in the governing Navier-Stokes and energy equations is used to incorporate source terms due to heat release from chemical reactions, density variation, and nonluminous radiative heat loss. Additionally, the conservation equation for chemical species is formulated by including a source term due to chemical reaction. To validate the model, we consider the combustion of n-heptane and n-butanol droplets in stagnant air using overall single-step reactions. The diameter history and flame standoff ratio obtained from the proposed LB method are found to be in good agreement with available numerical and experimental data. The present LB scheme is believed to be a promising approach for modeling spray combustion.

  6. Catalytic combustion in small wood burning appliances

    Energy Technology Data Exchange (ETDEWEB)

    Oravainen, H. [VTT Energy, Jyvaeskylae (Finland)

    1996-12-31

    There is over a million hand fired small heating appliances in Finland where about 5,4 million cubic meters of wood fuel is used. Combustion in such heating appliances is a batch-type process. In early stages of combustion when volatiles are burned, the formation of carbon monoxide (CO) and other combustible gases are difficult to avoid when using fuels that have high volatile matter content. Harmful emissions are formed mostly after each fuel adding but also during char burnout period. When the CO-content in flue gases is, say over 0.5 %, also other harmful emissions will be formed. Methane (CH{sub 4}) and other hydrocarbons are released and the amount of polycyclic aromatic hydrocarbons (PAH)-compounds can be remarkable. Some PAH-compounds are very carcinogenic. It has been estimated that in Finland even more than 90 % of hydrocarbon and PAH emissions are due to small scale wood combustion. Emissions from transportation is excluded from these figures. That is why wood combustion has a net effect on greenhouse gas phenomena. For example carbon monoxide emissions from small scale wood combustion are two fold compared to that of energy production in power plants. Methane emission is of the same order as emission from transportation and seven fold compared with those of energy production. Emissions from small heating appliances can be reduced by developing the combustion techniques, but also by using other means, for example catalytic converters. In certain stages of the batch combustion, temperature is not high enough, gas mixing is not good enough and residence time is too short for complete combustion. When placed to a suitable place inside a heating appliance, a catalytic converter can oxidize unburned gases in the flue gas into compounds that are not harmful to the environment. (3 refs.)

  7. Flammability characteristics of combustible gases and vapors

    Energy Technology Data Exchange (ETDEWEB)

    Zabetakis, M. G. [Bureau of Mines, Pittsburgh, PA (United States)

    1964-05-01

    This is a summary of the available limit of flammability, autoignition and burning-rate data for more than 200 combustible gases and vapors in air and other oxidants, as well as of empirical rules and graphs that can be used to predict similar data for thousands of other combustibles under a variety of environmental conditions. Spec$c data are presented on the paraffinic, unsaturated, aromatic, and alicyclic hydrocarbons, alcohols, ethers, aldehydes, ketones, and sulfur compounds, and an assortment of fuels, fuel blends, hydraulic fluids, engine oils, and miscellaneous combustible gases and vapors.

  8. Combustion temperature charts for industrial gaseous fuels

    Energy Technology Data Exchange (ETDEWEB)

    Matouskova, V.; Gerak, A.; Hlavacka, V.

    1975-12-01

    Researchers at Czechoslovakia's State Research Institute of Mechanical Engineering offer a method for calculating the theoretical flame temperature that includes the effect of endothermic reactions, especially the dissociation of combustion products. Charts presented for eight types of fuel gases can be used to determine the flame temperature relative to the temperature of the combustion air and to the excess-air ratio. Also considered is the relationship between these parameters and the characteristic temperature relationships for equipment using heat recovered from the flue gases to preheat incoming combustion air.

  9. Novel combustion concepts for sustainable energy development

    CERN Document Server

    Agarwal, Avinash K; Gupta, Ashwani K; Aggarwal, Suresh K; Kushari, Abhijit

    2014-01-01

    This book comprises research studies of novel work on combustion for sustainable energy development. It offers an insight into a few viable novel technologies for improved, efficient and sustainable utilization of combustion-based energy production using both fossil and bio fuels. Special emphasis is placed on micro-scale combustion systems that offer new challenges and opportunities. The book is divided into five sections, with chapters from 3-4 leading experts forming the core of each section. The book should prove useful to a variety of readers, including students, researchers, and professionals.

  10. 3rd International Conference on Numerical Combustion

    CERN Document Server

    Larrouturou, Bernard; Numerical Combustion

    1989-01-01

    Interest in numerical combustion is growing among applied mathematicians, physicists, chemists, engine manufacturers and many industrialists. This proceedings volume contains nine invited lectures and twenty seven contributions carefully selected by the editors. The major themes are numerical simulation of transsonic and supersonic combustion phenomena, the study of supersonic reacting mixing layers, and turbulent combustion. Emphasis is laid on hyperbolic models and on numerical simulations of hydrocarbon planes with a complete set of chemical reactions carried out in two-dimensional geometries as well as on complex reactive flow simulations.

  11. The John Zink Hamworthy combustion handbook

    CERN Document Server

    Baukal, Charles E

    2013-01-01

    Despite the length of time it has been around, its importance, and vast amounts of research, combustion is still far from being completely understood. Issues regarding the environment, cost, and fuel consumption add further complexity, particularly in the process and power generation industries. Dedicated to advancing the art and science of industrial combustion, The John Zink Hamworthy Combustion Handbook, Second Edition: Volume 3 - Applications offers comprehensive, up-to-date coverage of equipment used in the process and power generation industries. Under the leadership of Charles E. Baukal

  12. Annual Report: Advanced Combustion (30 September 2012)

    Energy Technology Data Exchange (ETDEWEB)

    Hawk, Jeffrey [NETL; Richards, George

    2012-09-30

    The Advanced Combustion Project addresses fundamental issues of fire-side and steam-side corrosion and materials performance in oxy-fuel combustion environments and provides an integrated approach into understanding the environmental and mechanical behavior such that environmental degradation can be ameliorated and long-term microstructural stability, and thus, mechanical performance can lead to longer lasting components and extended power plant life. The technical tasks of this effort are Oxy-combustion Environment Characterization, Alloy Modeling and Life Prediction, and Alloy Manufacturing and Process Development.

  13. MODELAGEM DE PROCESSOS UTILIZANDO O BPMN NA FACULDADE CATÓLICA RAINHA DO SERTÃO

    Directory of Open Access Journals (Sweden)

    Antonio Neuton da Silva Júnior

    2017-06-01

    Full Text Available O presente artigo apresenta o gerenciamento de negócios por processos, suas perspectivas atuais, suas vantagens, o desenvolvimento do projeto Modelagem de Processos utilizando BPMN implementado na Faculdade Católica Rainha do Sertão, as ferramentas utilizadas no projeto, a metodologia e os resultados obtidos a partir do mesmo. Ainda foi descrito os setores utilizados, a modelagem resultante das pesquisas e entrevistas e as sugestões para as melhorias dos processos modelados.

  14. Coal Combustion Science quarterly progress report, April--June 1990

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. (ed.); Baxter, L.L.; Fletcher, T.H.; Mitchell, R.E.

    1990-11-01

    This document provides a quarterly status report of the Coal Combustion Science Program that is being conducted at the Combustion, Research Facility, Sandia National Laboratories, Livermore, California. Coal devolatilization, coal char combustion, and fate of mineral matter during coal combustion. 56 refs., 25 figs., 13 tabs.

  15. Numerical modeling of straw combustion in a fixed bed

    DEFF Research Database (Denmark)

    Zhou, Haosheng; Jensen, Anker; Glarborg, Peter

    2005-01-01

    . The straw combustion processes include moisture evaporation, straw pyrolysis, gas combustion, and char combustion. The model provides detailed information of the structure of the ignition flame front. Simulated gas species concentrations at the bed surface, ignition flame front rate, and bed temperature...... packing condition, and heat capacity of the straw have considerable effects on the model predictions of straw combustion in the fixed bed....

  16. Key factors of combustion from kinetics to gas dynamics

    CERN Document Server

    Rubtsov, Nikolai M

    2017-01-01

    This book summarizes the main advances in the mechanisms of combustion processes. It focuses on the analysis of kinetic mechanisms of gas combustion processes and experimental investigation into the interrelation of kinetics and gas dynamics in gas combustion. The book is complimentary to the one previously published, The Modes of Gaseous Combustion.

  17. A study of the current group evaporation/combustion theories

    Science.gov (United States)

    Shen, Hayley H.

    1990-01-01

    Liquid fuel combustion can be greatly enhanced by disintegrating the liquid fuel into droplets, an effect achieved by various configurations. A number of experiments carried out in the seventies showed that combustion of droplet arrays and sprays do not form individual flames. Moreover, the rate of burning in spray combustion greatly deviates from that of the single combustion rate. Such observations naturally challenge its applicability to spray combustion. A number of mathematical models were developed to evaluate 'group combustion' and the related 'group evaporation' phenomena. This study investigates the similarity and difference of these models and their applicability to spray combustion. Future work that should be carried out in this area is indicated.

  18. Kinetics of coal combustion: Part 2, Mechanisms and kinetics of coal volatiles combustion

    Energy Technology Data Exchange (ETDEWEB)

    Gat, N.; Wolff, M. F.; Petach, M. B. [TRW Space and Technology Group, Redondo Beach, CA (USA)

    1988-12-01

    Presently very little is known about the combustion characteristics of mixtures of hydrocarbon fuels. Even less is known about the combustion of coal volatiles which are complex mixtures of light and high molecular weight hydrocarbons. This issue pertains not only to coal volatiles but also to the combustion of synthetic fuels, liquefaction and coal gasification products. The subject in general has been given very little attention in the literature. As a consequence, current modeling methods are based on assumptions which are not thoroughly validated and verified. The current investigation addressed this very problem of the combustion of mixtures of hydrocarbon fuels. 29 refs., 35 figs., 5 tabs.

  19. DIAGNOSIS OF FAILURE OF COMBUSTION IN THE COMBUSTION CHAMBER WITH A THERMOVISION EQUIPMENT

    Directory of Open Access Journals (Sweden)

    S. V. Vorobiev

    2014-01-01

    Full Text Available The use of thermovision technology to diagnose failure of the combustion flame test tube of the main combustion chamber gas turbine engine is deal with in the article. Join the thermal radiation of the jet of combustion products and the internal elements was carried out using short-wave thermovision system AGA-782 with spectral spectral filters in several ranges from 3.2 to 5.6 microns. Thermovision is mounted on the axis of the flame tube. The output signal was recorded and processed on a computer in real time, allowing monitor the combustion process and the thermal state of the object during the experiment.

  20. Coal Combustion Products Extension Program

    Energy Technology Data Exchange (ETDEWEB)

    Tarunjit S. Butalia; William E. Wolfe

    2006-01-11

    This final project report presents the activities and accomplishments of the ''Coal Combustion Products Extension Program'' conducted at The Ohio State University from August 1, 2000 to June 30, 2005 to advance the beneficial uses of coal combustion products (CCPs) in highway and construction, mine reclamation, agricultural, and manufacturing sectors. The objective of this technology transfer/research program at The Ohio State University was to promote the increased use of Ohio CCPs (fly ash, FGD material, bottom ash, and boiler slag) in applications that are technically sound, environmentally benign, and commercially competitive. The project objective was accomplished by housing the CCP Extension Program within The Ohio State University College of Engineering with support from the university Extension Service and The Ohio State University Research Foundation. Dr. Tarunjit S. Butalia, an internationally reputed CCP expert and registered professional engineer, was the program coordinator. The program coordinator acted as liaison among CCP stakeholders in the state, produced information sheets, provided expertise in the field to those who desired it, sponsored and co-sponsored seminars, meetings, and speaking at these events, and generally worked to promote knowledge about the productive and proper application of CCPs as useful raw materials. The major accomplishments of the program were: (1) Increase in FGD material utilization rate from 8% in 1997 to more than 20% in 2005, and an increase in overall CCP utilization rate of 21% in 1997 to just under 30% in 2005 for the State of Ohio. (2) Recognition as a ''voice of trust'' among Ohio and national CCP stakeholders (particularly regulatory agencies). (3) Establishment of a national and international reputation, especially for the use of FGD materials and fly ash in construction applications. It is recommended that to increase Ohio's CCP utilization rate from 30% in 2005 to

  1. Danish emission inventories for stationary combustion plants

    DEFF Research Database (Denmark)

    Nielsen, Malene; Nielsen, Ole-Kenneth; Plejdrup, Marlene Schmidt

    Emission inventories for stationary combustion plants are presented and the methodologies and assumptions used for the inventories are described. The pollutants considered are SO2, NOx, NMVOC, CH4, CO, CO2, N2O, particulate matter, heavy metals, dioxins, HCB and PAH. The CO2 emission in 2007 was 10...... incineration plants. The combustion of wood in residential plants has increased considerably in recent years resulting in increased emission of PAH, particulate matter and CO. The emission of NMVOC has increased since 1990 as a result of both the increased combustion of wood in residential plants...... and the increased emission from lean-burn gas engines. The dioxin emission decreased since 1990 due to flue gas cleaning on waste incineration plants. However in recent years the emission has increased as a result of the increased combustion of wood in residential plants....

  2. Danish emission inventories for stationary combustion plants

    DEFF Research Database (Denmark)

    Nielsen, Malene; Nielsen, Ole-Kenneth; Plejdrup, Marlene Schmidt

    Emission inventories for stationary combustion plants are presented and the methodologies and assumptions used for the inventories are described. The pollutants considered are SO2, NOx, NMVOC, CH4, CO, CO2, N2O, NH3, particulate matter, heavy metals, dioxins, HCB and PAH. The CO2 emission in 2008...... incineration plants. The combustion of wood in residential plants has increased considerably in recent years resulting in increased emission of PAH, particulate matter and CO. The emission of NMVOC has increased since 1990 as a result of both the increased combustion of wood in residential plants...... and the increased emission from lean-burn gas engines. The dioxin emission decreased since 1990 due to flue gas cleaning on waste incineration plants. However in recent years the emission has increased as a result of the increased combustion of wood in residential plants....

  3. Fuels Combustion Research: Supercritical Fuel Pyrolysis

    National Research Council Canada - National Science Library

    Glassman, Irvin

    2000-01-01

    .... The focus during the subject period was directed to understanding the pyrolysis and combustion of endothermic fuels under subcritical conditions and the pyrolysis of these fuels under supercritical conditions...

  4. Fuels Combustion Research: Supercritical Fuel Pyrolysis

    National Research Council Canada - National Science Library

    Glassman, Irvin

    2001-01-01

    .... The focus during the subject period was directed to understanding the pyrolysis and combustion of endothermic fuels under subcritical conditions and the pyrolysis of these fuels under supercritical conditions...

  5. Combustion properties of Kraft Black Liquors

    Energy Technology Data Exchange (ETDEWEB)

    Frederick, W.J. Jr.; Hupa, M. (Aabo Akademi, Turku (Finland))

    1993-04-01

    In a previous study of the phenomena involved in the combustion of black liquor droplets a numerical model was developed. The model required certain black liquor specific combustion information which was then not currently available, and additional data were needed for evaluating the model. The overall objectives of the project reported here was to provide experimental data on key aspects of black liquor combustion, to interpret the data, and to put it into a form which would be useful for computational models for recovery boilers. The specific topics to be investigated were the volatiles and char carbon yields from pyrolysis of single black liquor droplets; a criterion for the onset of devolatilization and the accompanying rapid swelling; and the surface temperature of black liquor droplets during pyrolysis, combustion, and gasification. Additional information on the swelling characteristics of black liquor droplets was also obtained as part of the experiments conducted.

  6. Petroleum recovery by in situ combustion

    Energy Technology Data Exchange (ETDEWEB)

    Orkiszewski, J.

    1968-09-10

    In an in situ combustion process for the recovery of oil, the available fuel is changed to more nearly equal the minimum fuel requirement for the process. The API gravity of the reservoir oil and the temperature of the reservoir are used to determine the total available fuel. The available fuel in the reservoir is changed to more nearly equal the minimum fuel requirement for the in situ combustion process by injecting a fluid capable of changing either the API gravity of the reservoir oil, the reservoir temperature, or both. An oxygen containing gas is then injected into the reservoir to initiate combustion. Oil is recovered from the reservoir as a result of the in situ combustion process. (10 claims)

  7. Plume Diagnostics for Combustion Stability Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Sierra Engineering Inc. and Purdue University propose to develop a non-intrusive plume instrument capable of detecting and diagnosing combustion instability. This...

  8. Two phase exhaust for internal combustion engine

    Science.gov (United States)

    Vuk, Carl T [Denver, IA

    2011-11-29

    An internal combustion engine having a reciprocating multi cylinder internal combustion engine with multiple valves. At least a pair of exhaust valves are provided and each supply a separate power extraction device. The first exhaust valves connect to a power turbine used to provide additional power to the engine either mechanically or electrically. The flow path from these exhaust valves is smaller in area and volume than a second flow path which is used to deliver products of combustion to a turbocharger turbine. The timing of the exhaust valve events is controlled to produce a higher grade of energy to the power turbine and enhance the ability to extract power from the combustion process.

  9. Plume Diagnostics for Combustion Stability Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Sierra Engineering and Purdue University propose to leverage combustion stability testing, already funded and planned for the second and third quarters of next year...

  10. 76 FR 16646 - Circadian, Inc., Clean Energy Combustion, Inc. (n/k/a Clean Energy Combustion Systems, Inc...

    Science.gov (United States)

    2011-03-24

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION Circadian, Inc., Clean Energy Combustion, Inc. (n/k/a Clean Energy Combustion Systems, Inc... concerning the securities of Clean Energy Combustion, Inc. (n/k/a Clean Energy Combustion Systems, Inc...

  11. Self-oscillations of an unstable fuel combustion in the combustion chamber of a liquid-propellant rocket engine

    Science.gov (United States)

    Gotsulenko, V. V.; Gotsulenko, V. N.

    2013-01-01

    The form of the self-oscillations of a vibrating combustion of a fuel in the combustion chamber of a liquidpropellant rocket engine, caused by the fuel-combustion lag and the heat release, was determined. The character of change in these self-oscillations with increase in the time of the fuel-combustion lag was investigated.

  12. Household fuels, direct combustion, public perception, fuel

    African Journals Online (AJOL)

    2005-07-10

    Jul 10, 2005 ... w ere smo k e, fl y - ash and high b urning rate . A ma j or c ause o f the p ro b lems w as the ... Key words: Household fuels, direct combustion, public perception, fuel-switching, food-switching, health impacts. 1 IN TR ..... levels from wood combustion typically exceed the recommended limit by 13 - 50 times ...

  13. Secondary combustion system for woodburning stove

    Energy Technology Data Exchange (ETDEWEB)

    von Conta, P. E. W.

    1985-11-19

    A secondary combustion system for a woodburning stove employs a concave shaped screen for dispersing exhaust gases. A mixing chamber is formed in an insulated conduit between the concave screen and a second planar screen. The planar screen is perforated to form a random array of flaps which increase the turbulence of the exhaust stream so that a secondary combustion of the exhaust gases is produced.

  14. L'Hidrogen com a combustible

    OpenAIRE

    Díaz i Pérez, Germán

    2005-01-01

    L’objectiu del projecte, és estudiar la viabilitat de l’hidrogen com a combustible net. Dissenyant un planta de producció d’hidrogen que utilitzi energia neta per a realitzar el seu procés (energia elèctrica obtinguda a partir de fonts renovables), i utilitzant l’hidrogen obtingut per a accionar un autobús amb pila de combustible.

  15. Internal combustion engine and method for control

    Science.gov (United States)

    Brennan, Daniel G

    2013-05-21

    In one exemplary embodiment of the invention an internal combustion engine includes a piston disposed in a cylinder, a valve configured to control flow of air into the cylinder and an actuator coupled to the valve to control a position of the valve. The internal combustion engine also includes a controller coupled to the actuator, wherein the controller is configured to close the valve when an uncontrolled condition for the internal engine is determined.

  16. Building America Expert Meeting. Combustion Safety

    Energy Technology Data Exchange (ETDEWEB)

    Brand, Larry [Partnership for Advanced Residential Retrofit (PARR), Des Plaines, IL (United States)

    2013-03-01

    This is an overview of "The Best Approach to Combustion Safety in a Direct Vent World," held June 28, 2012, in San Antonio, TX. The objective of this Expert Meeting was to identify gaps and barriers that need to be addressed by future research, and to develop data-driven technical recommendations for code updates so that a common approach for combustion safety can be adopted by all members of the building energy efficiency and code communities.

  17. Building America Expert Meeting: Combustion Safety

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L.

    2013-03-01

    This is a meeting overview of 'The Best Approach to Combustion Safety in a Direct Vent World', held June 28, 2012, in San Antonio, Texas. The objective of this Expert Meeting was to identify gaps and barriers that need to be addressed by future research, and to develop data-driven technical recommendations for code updates so that a common approach for combustion safety can be adopted by all members of the building energy efficiency and code communities.

  18. Fluidized bed combustion: mixing and pollutant limitation

    Energy Technology Data Exchange (ETDEWEB)

    Leckner, B. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Energy Conversion

    1997-10-01

    Fluidized bed combustion (FBC) has been applied commercially during a few decades, and sufficient knowledge is gained to design boilers with sizes of up to several hundreds of megawatt thermal power (MW{sub th}). The knowledge of what goes on inside a large combustion chamber is still limited, however, and this impedes further optimization and efficient solution of problems that might occur. Despite this lack of knowledge the present survey deals with combustion chamber processes and discusses mixing and distribution of fuel and air in the combustion chamber and its importance for sulphur capture and reduction of emissions of nitrogen oxides. It is desirable to present the material in a general way and to cover the entire field of FBC. However, the scarce openly published information deals mostly with coal combustion in atmospheric circulating fluidized bed (CFB) combustors, and therefore this application will receive most attention, but reference is also made to pressurized combustion and to other fuels than coal. In this context the important work made in the LIEKKI project on the analysis of different fuels and on the influence of pressure should be especially pointed out. (orig.)

  19. Rapid Deployment of Rich Catalytic Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Richard S. Tuthill

    2004-06-10

    The overall objective of this research under the Turbines Program is the deployment of fuel flexible rich catalytic combustion technology into high-pressure ratio industrial gas turbines. The resulting combustion systems will provide fuel flexibility for gas turbines to burn coal derived synthesis gas or natural gas and achieve NO{sub x} emissions of 2 ppmvd or less (at 15 percent O{sub 2}), cost effectively. This advance will signify a major step towards environmentally friendly electric power generation and coal-based energy independence for the United States. Under Phase 1 of the Program, Pratt & Whitney (P&W) performed a system integration study of rich catalytic combustion in a small high-pressure ratio industrial gas turbine with a silo combustion system that is easily scalable to a larger multi-chamber gas turbine system. An implementation plan for this technology also was studied. The principal achievement of the Phase 1 effort was the sizing of the catalytic module in a manner which allowed a single reactor (rather than multiple reactors) to be used by the combustion system, a conclusion regarding the amount of air that should be allocated to the reaction zone to achieve low emissions, definition of a combustion staging strategy to achieve low emissions, and mechanical integration of a Ceramic Matrix Composite (CMC) combustor liner with the catalytic module.

  20. Combustion kinetics and reaction pathways

    Energy Technology Data Exchange (ETDEWEB)

    Klemm, R.B.; Sutherland, J.W. [Brookhaven National Laboratory, Upton, NY (United States)

    1993-12-01

    This project is focused on the fundamental chemistry of combustion. The overall objectives are to determine rate constants for elementary reactions and to elucidate the pathways of multichannel reactions. A multitechnique approach that features three independent experiments provides unique capabilities in performing reliable kinetic measurements over an exceptionally wide range in temperature, 300 to 2500 K. Recent kinetic work has focused on experimental studies and theoretical calculations of the methane dissociation system (CH{sub 4} + Ar {yields} CH{sub 3} + H + Ar and H + CH{sub 4} {yields} CH{sub 3} + H{sub 2}). Additionally, a discharge flow-photoionization mass spectrometer (DF-PIMS) experiment is used to determine branching fractions for multichannel reactions and to measure ionization thresholds of free radicals. Thus, these photoionization experiments generate data that are relevant to both reaction pathways studies (reaction dynamics) and fundamental thermochemical research. Two distinct advantages of performing PIMS with high intensity, tunable vacuum ultraviolet light at the National Synchrotron Light Source are high detection sensitivity and exceptional selectivity in monitoring radical species.

  1. Carburetor for internal combustion engines

    Science.gov (United States)

    Csonka, John J.; Csonka, Albert B.

    1978-01-01

    A carburetor for internal combustion engines having a housing including a generally discoidal wall and a hub extending axially from the central portion thereof, an air valve having a relatively flat radially extending surface directed toward and concentric with said discoidal wall and with a central conoidal portion having its apex directed toward the interior of said hub portion. The housing wall and the radially extending surface of the valve define an air passage converging radially inwardly to form an annular valving construction and thence diverge into the interior of said hub. The hub includes an annular fuel passage terminating at its upper end in a circumferential series of micro-passages for directing liquid fuel uniformly distributed into said air passage substantially at said valving constriction at right angles to the direction of air flow. The air valve is adjustable axially toward and away from the discoidal wall of the carburetor housing to regulate the volume of air drawn into the engine with which said carburetor is associated. Fuel is delivered under pressure to the fuel metering valve and from there through said micro-passages and controlled cams simultaneously regulate the axial adjustment of said air valve and the rate of delivery of fuel through said micro-passages according to a predetermined ratio pattern. A third jointly controlled cam simultaneously regulates the ignition timing in accordance with various air and fuel supply settings. The air valve, fuel supply and ignition timing settings are all independent of the existing degree of engine vacuum.

  2. Real time identification of the internal combustion engine combustion parameters based on the vibration velocity signal

    Science.gov (United States)

    Zhao, Xiuliang; Cheng, Yong; Wang, Limei; Ji, Shaobo

    2017-03-01

    Accurate combustion parameters are the foundations of effective closed-loop control of engine combustion process. Some combustion parameters, including the start of combustion, the location of peak pressure, the maximum pressure rise rate and its location, can be identified from the engine block vibration signals. These signals often include non-combustion related contributions, which limit the prompt acquisition of the combustion parameters computationally. The main component in these non-combustion related contributions is considered to be caused by the reciprocating inertia force excitation (RIFE) of engine crank train. A mathematical model is established to describe the response of the RIFE. The parameters of the model are recognized with a pattern recognition algorithm, and the response of the RIFE is predicted and then the related contributions are removed from the measured vibration velocity signals. The combustion parameters are extracted from the feature points of the renovated vibration velocity signals. There are angle deviations between the feature points in the vibration velocity signals and those in the cylinder pressure signals. For the start of combustion, a system bias is adopted to correct the deviation and the error bound of the predicted parameters is within 1.1°. To predict the location of the maximum pressure rise rate and the location of the peak pressure, algorithms based on the proportion of high frequency components in the vibration velocity signals are introduced. Tests results show that the two parameters are able to be predicted within 0.7° and 0.8° error bound respectively. The increase from the knee point preceding the peak value point to the peak value in the vibration velocity signals is used to predict the value of the maximum pressure rise rate. Finally, a monitoring frame work is inferred to realize the combustion parameters prediction. Satisfactory prediction for combustion parameters in successive cycles is achieved, which

  3. Combustion stratification study of partially premixed combustion using Fourier transform analysis of OH* chemiluminescence images

    KAUST Repository

    Izadi Najafabadi, Mohammad

    2017-11-06

    A relatively high level of stratification (qualitatively: lack of homogeneity) is one of the main advantages of partially premixed combustion over the homogeneous charge compression ignition concept. Stratification can smooth the heat release rate and improve the controllability of combustion. In order to compare stratification levels of different partially premixed combustion strategies or other combustion concepts, an objective and meaningful definition of “stratification level” is required. Such a definition is currently lacking; qualitative/quantitative definitions in the literature cannot properly distinguish various levels of stratification. The main purpose of this study is to objectively define combustion stratification (not to be confused with fuel stratification) based on high-speed OH* chemiluminescence imaging, which is assumed to provide spatial information regarding heat release. Stratification essentially being equivalent to spatial structure, we base our definition on two-dimensional Fourier transforms of photographs of OH* chemiluminescence. A light-duty optical diesel engine has been used to perform the OH* bandpass imaging on. Four experimental points are evaluated, with injection timings in the homogeneous regime as well as in the stratified partially premixed combustion regime. Two-dimensional Fourier transforms translate these chemiluminescence images into a range of spatial frequencies. The frequency information is used to define combustion stratification, using a novel normalization procedure. The results indicate that this new definition, based on Fourier analysis of OH* bandpass images, overcomes the drawbacks of previous definitions used in the literature and is a promising method to compare the level of combustion stratification between different experiments.

  4. Improved Economic Performance of Municipal Solid Waste Combustion Plants by Model Based Combustion Control

    NARCIS (Netherlands)

    Leskens, M.

    2013-01-01

    The combustion of municipal solid waste (MSW) is used for its inertisation, reduction of its volume and the conversion of its energy content into heat and/or electricity. Operation and control of modern large scale MSW combustion (MSWC) plants is determined by economic and environmental objectives

  5. EMISSIONS OF TRACE PRODUCTS OF INCOMPLETE COMBUSTION FROM A PILOT-SCALE INCINERATOR SECONDARY COMBUSTION CHAMBER

    Science.gov (United States)

    Experiments were performed on a 73 kW rotary kiln incinerator simulator equipped with a 73 kW secondary combustion chamber (SCC) to examine emissions of products of incomplete combustion (PICs) resulting from incineration of carbon tetrachloride (CCl4) and dichlorometh...

  6. Potential of Porous-Media Combustion Technology as Applied to Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Miroslaw Weclas

    2010-01-01

    Full Text Available The paper summarizes the knowledge concerning porous media combustion techniques as applied in engines. One of most important reasons of this review is to introduce this still not well known technology to researchers doing with internal combustion engine processes, thermal engines, reactor thermodynamics, combustion, and material science. The paper gives an overview of possible applications of a highly porous open cell structures to in-cylinder processes. This application means utilization of unique features of porous media for supporting engine processes, especially fuel distribution in space, vaporization, mixing with air, heat recuperation, ignition and combustion. There are three ways for applying porous medium technology to engines: support of individual processes, support of homogeneous combustion process (catalytic and non-catalytic with temperature control, and utilization of the porous structure as a heat capacitor only. In the first type of application, the porous structure may be utilized for fuel vaporization and improved fuel distribution in space making the mixture more homogeneous in the combustion chamber. Extension of these processes to mixture formation and ignition inside a combustion reactor allows the realization of a homogeneous and a nearly zero emissions level combustion characterized by a homogeneous temperature field at reduced temperature level.

  7. Combustion Synthesis of Magnesium Aluminate

    Science.gov (United States)

    Kale, M. A.; Joshi, C. P.; Moharil, S. V.

    2011-10-01

    In the system MgO-Al2O3, three compounds MgAl2O4, MgAl6O10 (also expressed as- Mg0.4Al2.4O4) and MgAl26O40 are well known. Importance of the first two is well established. Magnesium aluminate (MgAl2O4) spinel is a technologically important material due to its interesting thermal properties. The MgAl2O4 ceramics also find application as humidity sensors. Apart from the luminescence studies, the interest in MgAl2O4 is due to various applications such as humidity-sensing and PEM fuel cells, TL/OSL dosimetry of the ionizing radiations, white light source. Interest in the MgAl6O10 has aroused due to possible use as a substrate for GaN growth. Attempt was made to synthesize these compounds by the combustion synthesis using metal nitrates as oxidizer and urea as a fuel. Compounds MgAl2O4 and MgAl6O10 were formed in a single step, while MgAl26O40 was not formed by this procedure. Activation of MgAl6O10 by rare earth ions like Ce3+, Eu3+ and Tb3+ and ns2 ion Pb2+ could be achieved. Excitation bands for MgAl6O10 are at slightly shorter wavelengths compared to those reported for MgAl2O4.

  8. Liquid rocket combustion chamber acoustic characterization

    Directory of Open Access Journals (Sweden)

    Cândido Magno de Souza

    2010-09-01

    Full Text Available Over the last 40 years, many solid and liquid rocket motors have experienced combustion instabilities. Among other causes, there is the interaction of acoustic modes with the combustion and/or fluid dynamic processes inside the combustion chamber. Studies have been showing that, even if less than 1% of the available energy is diverted to an acoustic mode, combustion instability can be generated. On one hand, this instability can lead to ballistic pressure changes, couple with other propulsion systems such as guidance or thrust vector control, and in the worst case, cause motor structural failure. In this case, measures, applying acoustic techniques, must be taken to correct/minimize these influences on the combustion. The combustion chamber acoustic behavior in operating conditions can be estimated by considering its behavior in room conditions. In this way, acoustic tests can be easily performed, thus identifying the cavity modes. This paper describes the procedures to characterize the acoustic behavior in the inner cavity of four different configurations of a combustion chamber. Simple analytical models are used to calculate the acoustic resonance frequencies and these results are compared with acoustic natural frequencies measured at room conditions. Some comments about the measurement procedures are done, as well as the next steps for the continuity of this research. The analytical and experimental procedures results showed good agreement. However, limitations on high frequency band as well as in the identification of specific kinds of modes indicate that numerical methods able to model the real cavity geometry and an acoustic experimental modal analysis may be necessary for a more complete analysis. Future works shall also consider the presence of passive acoustic devices such as baffles and resonators capable of introducing damping and avoiding or limiting acoustic instabilities.

  9. Controle e avaliação de um conjunto gaseificador-combustor de fluxo concorrente, utilizando como combustível a biomassa de lenha de eucalipto

    OpenAIRE

    Santos, William Rosário dos

    2008-01-01

    Nos dias atuais, há uma preocupação com questões ecológicas associadas à preservação dos recursos naturais visando à qualidade de vida atual e futura. Nesse contexto, a gaseificação de biomassa é uma tecnologia sustentável para a geração de energia, por apresentar baixa emissão de gases poluentes. Um dos problemas do uso do gaseificador para o aquecimento do ar em aviários é o desperdício de energia no período diurno, tendo em vista que o equipamento não dispõe de sistema de controle de potên...

  10. Criticality evaluation of long term for spent fuel, using Scale; Evaluacion de criticidad a largo plazo para combustible gastado, utilizando SCALE

    Energy Technology Data Exchange (ETDEWEB)

    Esquivel E, J.; Vargas E, S.; Ramirez S, J. R., E-mail: jaime.esquivel@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    Once carried out the spent fuel discharge, of the reactor core, this continues generating decay heat and diverse fission products, reason why is important to store this fuel inside containers able to dissipate the heat generated by the isotopes decay of the fuel and to maintain the fuels arrangement in subcritical condition. This means that: is necessary to assure the sub-criticality of those fuel assemblies in the time. This work, presents a criticality evaluation of fuel assemblies type PWR in a storage generic container. For this purpose have been used two codes: GeeWiz, to carry out the geometric model of the container with the fuel assemblies, and Keno, with which, the criticality of the full container with fuel is determined until a 10{sup 6} years period. These codes are part of the package Scale. The specifications for each one of the analyzed components are based on a Benchmark document of the Nea/OECD, of where, the results that reports are compared with the obtained results by the realized analysis. (Author)

  11. Investigating co-combustion characteristics of bamboo and wood.

    Science.gov (United States)

    Liang, Fang; Wang, Ruijuan; Jiang, Changle; Yang, Xiaomeng; Zhang, Tao; Hu, Wanhe; Mi, Bingbing; Liu, Zhijia

    2017-11-01

    To investigate co-combustion characteristics of bamboo and wood, moso bamboo and masson pine were torrefied and mixed with different blend ratios. The combustion process was examined by thermogravimetric analyzer (TGA). The results showed the combustion process of samples included volatile emission and oxidation combustion as well as char combustion. The main mass loss of biomass blends occurred at volatile emission and oxidation combustion stage, while that of torrefied biomass occurred at char combustion stage. With the increase of bamboo content, characteristic temperatures decreased. Compared with untreated biomass, torrefied biomass had a higher initial and burnout temperature. With the increase of heating rates, combustion process of samples shifted to higher temperatures. Compared with non-isothermal models, activation energy obtained from isothermal model was lower. The result is helpful to promote development of co-combustion of bamboo and masson pine wastes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Assessment of Literature Related to Combustion Appliance Venting Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, V. H.; Less, B. D.; Singer, B. C.; Stratton, J. C.; Wray, C. P.

    2015-02-01

    In many residential building retrofit programs, air tightening to increase energy efficiency is often constrained by safety concerns with naturally vented combustion appliances. Tighter residential buildings more readily depressurize when exhaust equipment is operated, making combustion appliances more prone to backdraft or spill combustion exhaust into the living space. Several measures, such as installation guidelines, vent sizing codes, and combustion safety diagnostics, are in place with the intent to prevent backdrafting and combustion spillage, but the diagnostics conflict and the risk mitigation objective is inconsistent. This literature review summarizes the metrics and diagnostics used to assess combustion safety, documents their technical basis, and investigates their risk mitigations. It compiles information from the following: codes for combustion appliance venting and installation; standards and guidelines for combustion safety diagnostics; research evaluating combustion safety diagnostics; research investigating wind effects on building depressurization and venting; and software for simulating vent system performance.

  13. Diesel oil combustion in fluidized bed; Combustion de aceite diesel en lecho fluidizado

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Cazares, Mario [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1992-07-01

    The effect of the fluidized bed depth in the combustion in burning diesel oil in a fluidized bed, was analyzed. A self sustained combustion was achieved injecting the oil with an injector that utilized a principle similar to an automobile carburetor venturi. Three different depths were studied and it was found that the deeper the bed, the greater the combustion efficiency. Combustion efficiencies were attained from 82% for a 100mm bed depth, up to 96% for a 200mm bed depth. The diminution in the efficiency was mainly attributed to unburned hydrocarbons and to the carbon carried over, which was observed in the black smoke at the stack outlet. Other phenomena registered were the temperature gradient between the lower part of the bed and the upper part, caused by the fluidization velocity; additionally it was observed that the air employed for the oil injection (carbureting air) is the most important parameter to attain a complete combustion. [Espanol] Se analizo el efecto de la profundidad del lecho en la combustion al quemar aceite diesel en un lecho fluidizado experimental. Se logro combustion autosostenida inyectando el aceite con un inyector que utilizo un principio similar al venturi del carburador de automovil. Se estudiaron tres diferentes profundidades del lecho y se encontro que a mayor profundidad del lecho, mayor eficiencia de la combustion. Se lograron eficiencias de la combustion desde 82% para el lecho de 100 mm de profundidad hasta 96% para el de 200 mm. La disminucion de la eficiencia se atribuyo, principalmente, a los hidrocarburos no quemados y al carbon arrastrado, lo cual se observo en el humo negro a la salida de la chimenea. Otros fenomenos registrados fueron el gradiente de temperatura entre la parte baja del lecho y la parte superior causado por la velocidad de fluidizacion; ademas, se observo que el aire utilizado para inyectar el aceite (aire de carburacion) es el parametro mas importante para lograr una combustion completa.

  14. Combustion Safety Simplified Test Protocol Field Study

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L [Gas Technology Inst., Des Plaines, IL (United States); Cautley, D. [Gas Technology Inst., Des Plaines, IL (United States); Bohac, D. [Gas Technology Inst., Des Plaines, IL (United States); Francisco, P. [Gas Technology Inst., Des Plaines, IL (United States); Shen, L. [Gas Technology Inst., Des Plaines, IL (United States); Gloss, S. [Gas Technology Inst., Des Plaines, IL (United States)

    2015-11-05

    "9Combustions safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives. A survey of state weatherization agencies on combustion safety issues, details of a field data collection instrumentation package, summary of data collected over seven months, data analysis and results are included. The project provides several key results. State weatherization agencies do not generally track combustion safety failures, the data from those that do suggest that there is little actual evidence that combustion safety failures due to spillage from non-dryer exhaust are common and that only a very small number of homes are subject to the failures. The project team collected field data on 11 houses in 2015. Of these homes, two houses that demonstrated prolonged and excessive spillage were also the only two with venting systems out of compliance with the National Fuel Gas Code. The remaining homes experienced spillage that only occasionally extended beyond the first minute of operation. Combustion zone depressurization, outdoor temperature, and operation of individual fans all provide statistically significant predictors of spillage.

  15. LIEKKI 2 - Combustion technology is environmental technology

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M. [Aabo Akademi, Turku (Finland)

    1996-12-31

    Finland has wide experience in applications of various combustion technologies and fuels and in supplying energy to industry and municipalities. Furthermore, combustion hardware and equipment are amongst our most important export products. Above all, fluidized bed boilers, recovery boilers for pulp mills and heavy diesel engines and diesel power plants have achieved excellent success in the world markets. Exports of these products alone have amounted to several billions of Finnish marks of annual sales in recent years. Within modern combustion technology, the objective is to control flue gas emissions as far as possible in the process itself, thus doing away with the need for the separate scrubbing of flue gases. To accomplish this it has been necessary to conduct a large amount of research on the details of the chemistry of combustion emissions and the flows in furnaces and engine cylinders. A host of completely new products are being developed for the combustion technology field. The LIEKKI programme has been particularly interested in so-called combined-cycle processes based on pressurized fluidized bed technology

  16. Design factors for stable lean premix combustion

    Energy Technology Data Exchange (ETDEWEB)

    Richards, G.A.; Yip, M.J.; Gemmen, R.S.

    1995-10-01

    The Advanced Turbine Systems (ATS) program includes the development of low-emission combustors. Low emissions have already been achieved by premixing fuel and air to avoid the hot gas pockets produced by nozzles without premixing. While the advantages of premixed combustion have been widely recognized, turbine developers using premixed nozzles have experienced repeated problems with combustion oscillations. Left uncontrolled, these oscillations can lead to pressure fluctuations capable of damaging engine hardware. Elimination of such oscillations is often difficult and time consuming - particularly when oscillations are discovered in the last stages of engine development. To address this issue, METC is studying oscillating combustion from lean premixing fuel nozzles. These tests are providing generic information on the mechanisms that contribute to oscillating behavior in gas turbines. METC is also investigating the use of so-called {open_quotes}active{close_quotes} control of combustion oscillations. This technique periodically injects fuel pulses into the combustor to disrupt the oscillating behavior. Recent results on active combustion control are presented in Gemmen et al. (1995) and Richards et al. (1995). This paper describes the status of METC efforts to avoid oscillations through simple design changes.

  17. Reaction and diffusion in turbulent combustion

    Energy Technology Data Exchange (ETDEWEB)

    Pope, S.B. [Mechanical and Aerospace Engineering, Ithaca, NY (United States)

    1993-12-01

    The motivation for this project is the need to obtain a better quantitative understanding of the technologically-important phenomenon of turbulent combustion. In nearly all applications in which fuel is burned-for example, fossil-fuel power plants, furnaces, gas-turbines and internal-combustion engines-the combustion takes place in a turbulent flow. Designers continually demand more quantitative information about this phenomenon-in the form of turbulent combustion models-so that they can design equipment with increased efficiency and decreased environmental impact. For some time the PI has been developing a class of turbulent combustion models known as PDF methods. These methods have the important virtue that both convection and reaction can be treated without turbulence-modelling assumptions. However, a mixing model is required to account for the effects of molecular diffusion. Currently, the available mixing models are known to have some significant defects. The major motivation of the project is to seek a better understanding of molecular diffusion in turbulent reactive flows, and hence to develop a better mixing model.

  18. Testing fireproof materials in a combustion chamber

    Directory of Open Access Journals (Sweden)

    Kulhavy Petr

    2017-01-01

    Full Text Available This article deals with a prototype concept, real experiment and numerical simulation of a combustion chamber, designed for testing fire resistance some new insulating composite materials. This concept of a device used for testing various materials, providing possibility of monitoring temperatures during controlled gas combustion. As a fuel for the combustion process propane butane mixture has been used and also several kinds of burners with various conditions of inlet air (forced, free and fuel flows were tested. The tested samples were layered sandwich materials based on various materials or foams, used as fillers in fire shutters. The temperature distribution was measured by using thermocouples. A simulation of whole concept of experimental chamber has been carried out as the non-premixed combustion process in the commercial final volume sw Pyrosim. The result was to design chamber with a construction suitable, according to the international standards, achieve the required values (temperature in time. Model of the combustion based on a stoichiometric defined mixture of gas and the tested layered samples showed good conformity with experimental results – i.e. thermal distribution inside and heat release rate that has gone through the sample.

  19. Dioxins and polyvinylchloride in combustion and fires.

    Science.gov (United States)

    Zhang, Mengmei; Buekens, Alfons; Jiang, Xuguang; Li, Xiaodong

    2015-07-01

    This review on polyvinylchloride (PVC) and dioxins collects, collates, and compares data from selected sources on the formation of polychlorinated dibenzofurans (PCDFs) and dibenzo-p-dioxins (PCDDs), or in brief dioxins, in combustion and fires. In professional spheres, the incineration of PVC as part of municipal solid waste is seldom seen as a problem, since deep flue gas cleaning is required anyhow. Conversely, with its high content of chlorine, PVC is frequently branded as a major chlorine donor and spitefully leads to substantial formation of dioxins during poorly controlled or uncontrolled combustion and open fires. Numerous still ill-documented and diverse factors of influence may affect the formation of dioxins during combustion: on the one hand PVC-compounds represent an array of materials with widely different formulations; on the other hand these may all be exposed to fires of different nature and consequences. Hence, attention should be paid to PVC with respect to the ignition and development of fires, as well as attenuating the emission of objectionable compounds, such as carbon monoxide, hydrogen chloride, polycyclic aromatic hydrocarbons, and dioxins. This review summarises available dioxin emissions data, gathers experimental and simulation studies of fires and combustion tests involving PVC, and identifies and analyses the effects of several local factors of influence, affecting the formation of dioxins during PVC combustion. © The Author(s) 2015.

  20. Testing fireproof materials in a combustion chamber

    Science.gov (United States)

    Kulhavy, Petr; Martinec, Tomas; Novak, Ondrej; Petru, Michal; Srb, Pavel

    This article deals with a prototype concept, real experiment and numerical simulation of a combustion chamber, designed for testing fire resistance some new insulating composite materials. This concept of a device used for testing various materials, providing possibility of monitoring temperatures during controlled gas combustion. As a fuel for the combustion process propane butane mixture has been used and also several kinds of burners with various conditions of inlet air (forced, free) and fuel flows were tested. The tested samples were layered sandwich materials based on various materials or foams, used as fillers in fire shutters. The temperature distribution was measured by using thermocouples. A simulation of whole concept of experimental chamber has been carried out as the non-premixed combustion process in the commercial final volume sw Pyrosim. The result was to design chamber with a construction suitable, according to the international standards, achieve the required values (temperature in time). Model of the combustion based on a stoichiometric defined mixture of gas and the tested layered samples showed good conformity with experimental results - i.e. thermal distribution inside and heat release rate that has gone through the sample.

  1. LOX/Hydrocarbon Combustion Instability Investigation

    Science.gov (United States)

    Jensen, R. J.; Dodson, H. C.; Claflin, S. E.

    1989-01-01

    The LOX/Hydrocarbon Combustion Instability Investigation Program was structured to determine if the use of light hydrocarbon combustion fuels with liquid oxygen (LOX) produces combustion performance and stability behavior similar to the LOX/hydrogen propellant combination. In particular methane was investigated to determine if that fuel can be rated for combustion instability using the same techniques as previously used for LOX/hydrogen. These techniques included fuel temperature ramping and stability bomb tests. The hot fire program probed the combustion behavior of methane from ambient to subambient temperatures. Very interesting results were obtained from this program that have potential importance to future LOX/methane development programs. A very thorough and carefully reasoned documentation of the experimental data obtained is contained. The hot fire test logic and the associated tests are discussed. Subscale performance and stability rating testing was accomplished using 40,000 lb. thrust class hardware. Stability rating tests used both bombs and fuel temperature ramping techniques. The test program was successful in generating data for the evaluation of the methane stability characteristics relative to hydrogen and to anchor stability models. Data correlations, performance analysis, stability analyses, and key stability margin enhancement parameters are discussed.

  2. Desarrollo de apio minimamente procesado fortificado con vitamina e, utilizando la ingenieria de matrices

    OpenAIRE

    MARTELO CASTAÑO, YISELL JOHAN; CORTES RODRIGUEZ, MISAEL; SUAREZ MAHECHA, HÉCTOR

    2011-01-01

    El objetivo de este trabajo fue desarrollar un producto minimamente procesado fortificado con vitamina E, a partir de apio (Apium graveolens L. var.dulce), utilizando la ingenieria de matrices como metodologia de obtencion de alimentos funcionales. Trozos de apio impregnados al vacio con dl¿¿tocoferol acetato emulsificado en una solucion isotonica al vegetal de NaCl, 1,2%, fueron evaluados en funcion del tiempo de almacenamiento y el envasado (con y sin vacio), en terminos de la cuantificacio...

  3. Integración de aplicaciones/servicios web utilizando firma digital

    OpenAIRE

    Fonseca, Viviana; Romero, Dalila

    2007-01-01

    La firma digital es una tecnología que se ha ido expandiendo en aplicaciones de red, acceso a sitios seguros, conexiones seguras, etc. Esta tecnología esta descripta con mayor detalle en las tesis de grado “Utilizando Firma Digital” de Paula Venosa - Verónica Fredes y en “Implementando Firma Digital con J2EE” de Alejandro Falcone y María Clemens, sin embargo, el uso de firma digital en sistema transaccionales no se ha expandido. El presente trabajo tiene por objetivo ilustrar cómo es la pr...

  4. Desenvolvimento de biossensores utilizando nanotubos de carbono e nanopartículas de ouro

    OpenAIRE

    Bruno Campos Janegitz

    2012-01-01

    Primeiramente desenvolveu-se uma nova arquitetura de um biossensor para glicose utilizando-se a enzima glicose oxidase (GOx) imobilizada em nanotubos de carbono funcionalizados (CNTs) e dihexadecil hidrogenio fosfato (DHP) sobre a superficie de carbono vitreo (GCE). Resultados de voltametria ciclica apresentaram um par de picos redox bem definidos, correspondente a transferencia eletronica direta da GOx para o eletrodo, com o potencial formal de -0,418 V (vs. Ag/AgCl (KCl 3,0 mol L-1)). O bio...

  5. Sistema de evaluación de competencias en Educación Superior utilizando Moodle

    OpenAIRE

    María José BEZANILLA; Sonia ARRANZ

    2016-01-01

    El artículo presenta el diseño de un sistema original de evaluación de competencias utilizando el libro de calificaciones de Moodle. La implantación del modelo de Aprendizaje Basado en Competencias en Educación Superior exige nuevos sistemas de evaluación que sean coherentes con este enfoque. Aunque existen diversos desarrollos tecnológicos para la evaluación de competencias, algunos de los cuales se analizan en este artículo, ninguno responde en su totalidad a modelos com...

  6. Mecánica orbital para un viaje interestelar utilizando velas solares

    OpenAIRE

    Rocas Alonso, Marc; Mendez Heredero, Adrià

    2016-01-01

    Es sabido que el espacio es y será objeto de estudios e investigaciones para responder algunas de las preguntas más antiguas de la humanidad. El propósito inicial del trabajo surgió del planteamiento sobre la viabilidad de realizar una misión espacial cuya meta fuese llegar a las inmediaciones de una estrella diferente al Sol utilizando un método de propulsión viable. El trabajo consiste en dos partes considerablemente diferenciadas. En primer lugar se presenta un estudio del estado del...

  7. Controle de Colletotrichum gloeosporioides em mamoeiro, utilizando extratos vegetais, indutores de resistência e fungicida

    OpenAIRE

    Nascimento,Luciana Cordeiro do; Nery, Aparecida Rodrigues; Rodrigues,Luís Nery

    2008-01-01

    O presente trabalho teve como objetivo avaliar o controle de doenças do mamoeiro, utilizando extratos vegetais (alho, angico e manjericão), óleos naturais (urucum e algodão), indutores de resistência (Bion®, Ecolife® e Agro-mos®) e fungicida Mancozeb/Dithane. O Experimento I consistiu-se da avaliação dos tratamentos sobre o crescimento micelial de Colletotrichum gloeosporioides, in vitro; no Experimento II, efetuou-se a inoculação artificial do fungo sobre frutos sadios de mamão e avaliou-se ...

  8. Monitoramento dos extratos brutos de espécies de Polygala (Polygalaceae utilizando Artemia salina

    Directory of Open Access Journals (Sweden)

    A.B.P. Montanher

    Full Text Available Extratos de duas espécies de Polygala foram submetidos a um biomonitoramento utilizando o teste de toxicidade frente a Artemia salina, com a finalidade de detectar atividade citotóxica. Os resultados obtidos para o extrato bruto, frações hexânica e diclorometano de Polygala sabulosa Aw. Benn. mostraram-se promissores. No entanto, bioensaios mais específicos devem ser encorajados nos extratos vegetais que apresentam atividade diante deste bioensaio, a fim de confirmar estas conclusões.

  9. AVALIAÇÃO SENSORIAL DE VINHAS RIESLING ITÁLICO NACIONAIS UTILIZANDO PERFIL LIVRE

    OpenAIRE

    BENASSI,Marta de Toledo; DAMÁSIO,Maria Helena; CECCHI,Heloísa Máscia

    1998-01-01

    A literatura cita um grande número de trabalhos envolvendo análise sensorial descritiva para vinhos. Perfil Livre, uma nova técnica descritiva, foi utilizado na caracterização em termos de aparência, sabor e aroma para sete amostras de vinhos brancos Riesling Itálico nacionais. Doze provadores, sem experiência anterior com a técnica, foram selecionados utilizando-se teste triangular. Para o levantamento de atributos foi empregado o método rede. O número de atributos levantados por provador va...

  10. Serviços de gerenciamento ODP utilizando a arquitetura CORBA

    OpenAIRE

    Douglas Evangelista de Araujo

    1996-01-01

    Resumo: O crescente desenvolvimento tecnológico e o aumento da demanda por sistemas e aplicações distribuídas levaram à definição de um padrão para processamento distribuído aberto, RM-ODP (Reference Model for Open Distributed Processing), e ao surgimento de plataformas comerciais capazes de integrar aplicações que estão espalhadas em um ambiente heterogêneo. O trabalho representa uma proposta para implementação de alguns dos serviços básicos do RM-ODP utilizando uma arquitetura de integração...

  11. Ignition and wave processes in combustion of solids

    CERN Document Server

    Rubtsov, Nickolai M; Alymov, Michail I

    2017-01-01

    This book focuses on the application of classical combustion theory to ignition and flame propagation in solid-solid and gas-solid systems. It presents experimental investigations in the areas of local ignition, filtration combustion, self-propagating high temperature synthesis and nanopowders protection. The authors highlight analytical formulas used in different areas of combustion in solids and propose an approach based on classical combustion theory. The book attempts to analyze the basic approaches to understanding of solid-solid and solid - gas combustion presented in contemporary literature in a unified approach based on classical combustion theory. .

  12. A comparative study of combustible cartridge case materials

    Directory of Open Access Journals (Sweden)

    Wei-tao Yang

    2017-06-01

    Full Text Available Foamed combustible material based on polymer bonded RDX was fabricated using CO2 as foaming agent. The inner structures of felted and foamed combustible materials were presented by SEM. The two materials presented different formulations and inner porous structures. The combustion behaviors of felted and foamed materials were investigated by closed vessel test. Simultaneously, the co-combustion behavior of combustible cartridge case with 7-perf consolidated propellants was also investigated. The results of closed vessel test is applicable to gun system which is made of the foamed combustible material as component.

  13. Transport Properties for Combustion Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.J.; Bastein, L.; Price, P.N.

    2010-02-19

    This review examines current approximations and approaches that underlie the evaluation of transport properties for combustion modeling applications. Discussed in the review are: the intermolecular potential and its descriptive molecular parameters; various approaches to evaluating collision integrals; supporting data required for the evaluation of transport properties; commonly used computer programs for predicting transport properties; the quality of experimental measurements and their importance for validating or rejecting approximations to property estimation; the interpretation of corresponding states; combination rules that yield pair molecular potential parameters for unlike species from like species parameters; and mixture approximations. The insensitivity of transport properties to intermolecular forces is noted, especially the non-uniqueness of the supporting potential parameters. Viscosity experiments of pure substances and binary mixtures measured post 1970 are used to evaluate a number of approximations; the intermediate temperature range 1 < T* < 10, where T* is kT/{var_epsilon}, is emphasized since this is where rich data sets are available. When suitable potential parameters are used, errors in transport property predictions for pure substances and binary mixtures are less than 5 %, when they are calculated using the approaches of Kee et al.; Mason, Kestin, and Uribe; Paul and Warnatz; or Ern and Giovangigli. Recommendations stemming from the review include (1) revisiting the supporting data required by the various computational approaches, and updating the data sets with accurate potential parameters, dipole moments, and polarizabilities; (2) characterizing the range of parameter space over which the fit to experimental data is good, rather than the current practice of reporting only the parameter set that best fits the data; (3) looking for improved combining rules, since existing rules were found to under-predict the viscosity in most cases; (4

  14. Danish emission inventories for stationary combustion plants

    DEFF Research Database (Denmark)

    Nielsen, M.; Illerup, J. B.

    Emission inventories for stationary combustion plants are presented and the methodologies and assumptions used for the inventories are described. The pollutants considered are: SO2, NOx, NMVOC, CH4, CO, CO2, N2O, particulate matter, heavy metals, dioxins and PAH. Since 1990 the fuel consumption...... in stationary combustion has increased by 12% - the fossil fuel consumption however only by 6%. Despite the increased fuel consumption the emission of several pollutants have decreased due to the improved flue gas cleaning technology, improved burner technology and the change of fuel type used. A considerable...... plants. The emission of PAH increased as a result of the increased combustion of wood in residential boilers and stoves. Uncertainties for the emissions and trends have been estimated....

  15. Danish emission inventories for stationary combustion plants

    DEFF Research Database (Denmark)

    Nielsen, Malene; Nielsen, Ole-Kenneth; Plejdrup, Marlene Schmidt

    Emission inventories for stationary combustion plants are presented and the methodologies and assumptions used for the inventories are described. The pollutants considered are SO2, NOx, NMVOC, CH4, CO, CO2, N2O, NH3, particulate matter, heavy metals, PCDD/F, HCB and PAH. The CO2 emission in 2011...... of decreased emissions from large power plants and waste incineration plants. The combustion of wood in residential plants has increased considerably until 2007 resulting in increased emission of PAH and particulate matter. The emission of NMVOC has increased since 1990 as a result of both the increased...... combustion of wood in residential plants and the increased emission from lean-burn gas engines. The PCDD/F emission decreased since 1990 due to flue gas cleaning on waste incineration plants....

  16. Danish emission inventories for stationary combustion plants

    DEFF Research Database (Denmark)

    Nielsen, M.; Illerup, J. B.

    Emission inventories for stationary combustion plants are presented and the methodologies and assumptions used for the inventories are described. The pollutants considered are SO2, NOX, NMVOC, CH4, CO, CO2, N2O, particulate matter, heavy metals, dioxins and PAH. Since 1990 the fuel consumption...... in stationary combustion has increased by 14% - the fossil fuel consumption however only by 8%. Despite the increased fuel consumption the emission of several pollutants has decreased due to the improved flue gas cleaning technology, improved burner technology and the change of fuel type used. A considerable...... plants. The emission of PAH increased as a result of the increased combustion of wood in residential boilers and stoves. Uncertainties for the emissions and trends have been estimated...

  17. Internal Combustion Engines as Fluidized Bed Reactors

    Science.gov (United States)

    Lavich, Zoe; Taie, Zachary; Menon, Shyam; Beckwith, Walter; Daly, Shane; Halliday, Devin; Hagen, Christopher

    2016-11-01

    Using an internal combustion engine as a chemical reactor could provide high throughput, high chemical conversion efficiency, and reactant/product handling benefits. For processes requiring a solid catalyst, the ability to develop a fluidized bed within the engine cylinder would allow efficient processing of large volumes of fluid. This work examines the fluidization behavior of particles in a cylinder of an internal combustion engine at various engine speeds. For 40 micron silica gel particles in a modified Megatech Mark III transparent combustion engine, calculations indicate that a maximum engine speed of about 60.8 RPM would result in fluidization. At higher speeds, the fluidization behavior is expected to deteriorate. Experiments gave qualitative confirmation of the analytical predictions, as a speed of 48 RPM resulted in fluidized behavior, while a speed of 171 RPM did not. The investigation shows that under certain conditions a fluidized bed can be obtained within an engine cylinder. Corresponding Author.

  18. Analysis of circulating fluidized bed combustion technology

    Energy Technology Data Exchange (ETDEWEB)

    Furusawa, Takehiko; Shimizu, Tadaaki; Yang, Guilin

    1987-05-20

    Fluidized bed combustors are commercialized as a technology to combust solid fuels with higher efficiency and lower emission and have functions of both combustion and simultaneous desulfurization and NOx reduction with dense phase fluidized beds but it is not so easy to realize these problems. The technology of circulating fluidized bed coal combustion is expected to offer potential break-through of various problems. But the details are not reported so far. Quantitative analysis of present situations was conducted and future problems were shown with officially available informations. This analysis includes the circulating rate and loading of solids, heat recovery and heat transfer rate as a function of loading of solids, the design of cyclones related to high solid concentration within the combustor, sulfur retention with reduced Ca/S ratio and problems related to NOx reduction to be developed in future. (51 refs, 23 figs, 8 tabs)

  19. Spectroscopy, Kinetics, and Dynamics of Combustion Radicals

    Energy Technology Data Exchange (ETDEWEB)

    Nesbitt, David J. [Research/Professor

    2013-08-06

    Spectroscopy, kinetics and dynamics of jet cooled hydrocarbon transients relevant to the DOE combustion mission have been explored, exploiting i) high resolution IR lasers, ii) slit discharge sources for formation of jet cooled radicals, and iii) high sensitivity detection with direct laser absorption methods and near the quantum shot noise limit. What makes this combination powerful is that such transients can be made under high concentrations and pressures characteristic of actual combustion conditions, and yet with the resulting species rapidly cooled (T ≈10-15K) in the slit supersonic expansion. Combined with the power of IR laser absorption methods, this provides novel access to spectral detection and study of many critical combustion species.

  20. Improved bitumen extraction using wet combustion

    Energy Technology Data Exchange (ETDEWEB)

    Wylie, I.; Hagen, D.; McGuire, A. [VAST Power Systems Inc., Elkhart, IN (United States)

    2007-07-01

    This presentation outlined the main concerns regarding the current combustion paradigm for steam assisted gravity drainage (SAGD) bitumen extraction and provided a solution that is more energy efficient with less environmental impact. SAGD operations currently use dry steam injection to deliver heat and reduce the viscosity bitumen, but this results in heat loss, restricted fuel choices, high water use and high emissions. Vast Power Systems Inc. has developed a wet flue gas known as VASTgas{sup TM} for efficient extraction. The downhole fluid has a much higher heat output and much lower emissions of nitrogen oxides, carbon monoxide and carbon dioxide. Other key advantages include net clean water from combustion and electricity as a by-product. This presentation also described the advantages of the VASThermogenerator{sup TM} for SAGD which solves some of the concerns regarding the combustion paradigm of mined bitumen and tailings pond purification. figs.

  1. Processing of hydroxyapatite obtained by combustion synthesis

    Directory of Open Access Journals (Sweden)

    M. Canillas

    2017-09-01

    Full Text Available One of the reasons of implants failure are the stress forces appearing in the material–tissue interface due to the differences between their mechanical properties. For this reason, similar mechanical properties to the surrounding tissue are desirable. The synthesis of hydroxyapatite by solution combustion method and its processing have been studied in order to obtain fully dense ceramic bodies with improved mechanical strength. Combustion synthesis provides nanostructured powders characterized by a high surface area to facilitate the following sintering. Moreover, synthesis was conducted in aqueous and oxidizing media. Oxidizing media improve homogenization and increase the energy released during combustion. It gives rise to particles whose morphology and size suggest lower surface energies compared with aqueous media. The obtained powders were sintered by using a controlled sintering rate schedule. Lower surfaces energies minimize the shrinkage during sintering and relative densities measurements and diametral compression test confirm improved densification and consequently mechanical properties.

  2. OPTIMIZACION DE LA CONCENTRACION POR EVAPORACION OSMOTICA DEL JUGO DE MARACUYA (Passifora edullis)

    National Research Council Canada - National Science Library

    FREDDY FORERO LONGAS; CARLOS ANTONIO VE'LEZ PASOS

    2013-01-01

    ... fisicoquímicamente, el jugo fue ultrafiltrado en un sistema Pellicon 2® con membranas planas (10 kDa) y área 0.5 m2. Para la optimización se aplicó un diseño experimental tipo superficie de respuesta, estudiando el efecto de 3 factores...

  3. Establishment of Combustion Model for Isooctane HCCI Marine Diesel Engine and Research on the Combustion Characteristic

    Directory of Open Access Journals (Sweden)

    Li Biao

    2016-01-01

    Full Text Available The homogeneous charge compression ignition (HCCI combustion mode applied in marine diesel engine is expected to be one of alternative technologies to decrease nitrogen oxide (NOX emission and improve energy utilization rate. Applying the chemical-looping combustion (CLC mechanism inside the cylinder, a numerical study on the HCCI combustion process is performed taking a marine diesel engine as application object. The characteristic feature of combustion process is displayed. On this basis, the formation and emission of NOX are analyzed and discussed. The results indicate that the HCCI combustion mode always exhibit two combustion releasing heats: low-temperature reaction and high-temperature reaction. The combustion phase is divided into low-temperature reaction zone, high-temperature reaction zone and negative temperature coefficient (NTC zone. The operating conditions of the high compression ratio, high intake air temperature, low inlet pressure and small excess air coefficient would cause the high in-cylinder pressure which often leads engine detonation. The low compression ratio, low intake air temperature and big excess air coefficient would cause the low combustor temperature which is conducive to reduce NOX emissions. These technological means and operating conditions are expected to meet the NOX emissions limits in MARPOL73/78 Convention-Annex VI Amendment.

  4. Numerical simulation of combustion and soot under partially premixed combustion of low-octane gasoline

    KAUST Repository

    An, Yanzhao

    2017-09-23

    In-cylinder combustion visualization and engine-out soot particle emissions were investigated in an optical diesel engine fueled with low octane gasoline. Single injection strategy with an early injection timing (−30 CAD aTDC) was employed to achieve partially premixed combustion (PPC) condition. A high-speed color camera was used to record the combustion images for 150 cycles. The regulated emission of carbon dioxide, carbon monoxide, nitrogen oxides and soot mass concentration were measured experimentally. Full cycle engine simulations were performed using CONVERGE™ and the simulation results matched with the experimental results. The in-cylinder soot particle evolution was performed by coupling a reduced toluene reference fuel mechanism including the PAHs formation/oxidation reactions with particulate size mimic model. The results showed that PPC presents typical stratified combustion characteristics, which is significantly different from the conventional diesel spray-driven combustion. The in-cylinder temperature and equivalence ratio overlaid with soot-NO formation regime revealed that PPC operating condition under study mostly avoided the main sooting conditions throughout the entire combustion. The evaluation of temperature distribution showed formaldehyde could be regarded as an indicator for low temperature reactions, while hydroxyl group represents the high temperature reactions. Soot evolution happened during the combustion process, hydroxyl radicals promoted the soot oxidation.

  5. Sounding Solid Combustibles: Non-premixed Flame Sound Synthesis for Different Solid Combustibles.

    Science.gov (United States)

    Yin, Qiang; Liu, Shiguang

    2016-12-21

    With the rapidly growing VR industry, in recent years, more and more attention has been paid for fire sound synthesis. However, previous methods usually ignore the influences of the different solid combustibles, leading to unrealistic sounding results. This paper proposes SSC (sounding solid combustibles), which is a new recording-driven non-premixed flame sound synthesis framework accounting for different solid combustibles. SSC consists of three components: combustion noise, vortex noise and popping sounds. The popping sounds are the keys to distinguish the differences of solid combustibles. To improve the quality of fire sound, we extract the features of popping sounds from the real fire sound examples based on modified Empirical Mode Decomposition (EMD) method. Unlike previous methods, we take both direct combustion noise and vortex noise into account because the fire model is non-premixed flame. In our method, we also greatly resolve the synchronization problem during blending the three components of SSC. Due to the introduction of the popping sounds, it is easy to distinguish the fire sounds of different solid combustibles by our method, with great potential in practical applications such as games, VR system, etc. Various experiments and comparisons are presented to validate our method.

  6. Large eddy simulation and combustion instabilities; Simulation des grandes echelles et instabilites de combustion

    Energy Technology Data Exchange (ETDEWEB)

    Lartigue, G.

    2004-11-15

    The new european laws on pollutants emission impose more and more constraints to motorists. This is particularly true for gas turbines manufacturers, that must design motors operating with very fuel-lean mixtures. Doing so, pollutants formation is significantly reduced but the problem of combustion stability arises. Actually, combustion regimes that have a large excess of air are naturally more sensitive to combustion instabilities. Numerical predictions of these instabilities is thus a key issue for many industrial involved in energy production. This thesis work tries to show that recent numerical tools are now able to predict these combustion instabilities. Particularly, the Large Eddy Simulation method, when implemented in a compressible CFD code, is able to take into account the main processes involved in combustion instabilities, such as acoustics and flame/vortex interaction. This work describes a new formulation of a Large Eddy Simulation numerical code that enables to take into account very precisely thermodynamics and chemistry, that are essential in combustion phenomena. A validation of this work will be presented in a complex geometry (the PRECCINSTA burner). Our numerical results will be successfully compared with experimental data gathered at DLR Stuttgart (Germany). Moreover, a detailed analysis of the acoustics in this configuration will be presented, as well as its interaction with the combustion. For this acoustics analysis, another CERFACS code has been extensively used, the Helmholtz solver AVSP. (author)

  7. Experimental numerical study utilizing CFD in a stratified gasifier operating with biomass; Estudio numerico experimental de un gasificador estratificado que opera con biomasa, utilizando CFD

    Energy Technology Data Exchange (ETDEWEB)

    Rogel Ramirez, Alejandro

    2007-07-01

    The central idea behind this work is the developing of a numeric-experimental model, useful to optimize the biomass stratified gasifier design. Firstly, model validation will be carried up by comparison with reference experimental data available. This study describes a 1-D + 2-D numerical model used to simulate the gasification of pine wood pellets in a stratified downdraft gasifier whereby Eulerian conservation equations are solved for particle and gas phase components, velocities and specific enthalpies. The model takes into account the biomass particle process such as heating up, drying, primary pyrolysis of biomass, secondary pyrolysis of tar, homogeneous reactions and heterogeneous combustion/gasification reactions, and particle size change. This CFD model can be used to predict temperature profiles, gas composition, producer gas lower heating value, and carbon conversion efficiency, and the reactor performance when operating parameters and feed properties are changed. The standard {kappa}-{epsilon} and RNG {kappa}-{epsilon} models were used to simulate the turbulent flow conditions. [Spanish] La idea central del presente trabajo es el desarrollo de un modelo numerico- experimental, para optimizar el diseno de gasificadores estratificados de biomasa. Primeramente, el modelo sera validado utilizando datos experimentales disponibles en la literatura. Este estudio describe un modelo numerico 1-D+2-D, utilizado para simular la gasificacion de 'pelets' de madera de pino en un gasificador estratificado de flujos paralelos, en el que se resuelven ecuaciones de conservacion Eulerianas para los componentes de la fase gaseosa, la fase solida, velocidades y entalpias especificas. El modelo considera procesos como: calentamiento, secado de la biomasa, pirolisis primaria de la madera, pirolisis secundaria de los alquitranes, reacciones homogeneas, reacciones heterogeneas de combustion/gasificacion y cambio en el tamano de la particula. Este modelo CFD puede ser

  8. Dust Combustion Safety Issues for Fusion Applications

    Energy Technology Data Exchange (ETDEWEB)

    L. C. Cadwallader

    2003-05-01

    This report summarizes the results of a safety research task to identify the safety issues and phenomenology of metallic dust fires and explosions that are postulated for fusion experiments. There are a variety of metal dusts that are created by plasma erosion and disruptions within the plasma chamber, as well as normal industrial dusts generated in the more conventional equipment in the balance of plant. For fusion, in-vessel dusts are generally mixtures of several elements; that is, the constituent elements in alloys and the variety of elements used for in-vessel materials. For example, in-vessel dust could be composed of beryllium from a first wall coating, tungsten from a divertor plate, copper from a plasma heating antenna or diagnostic, and perhaps some iron and chromium from the steel vessel wall or titanium and vanadium from the vessel wall. Each of these elements has its own unique combustion characteristics, and mixtures of elements must be evaluated for the mixture’s combustion properties. Issues of particle size, dust temperature, and presence of other combustible materials (i.e., deuterium and tritium) also affect combustion in air. Combustion in other gases has also been investigated to determine if there are safety concerns with “inert” atmospheres, such as nitrogen. Several coolants have also been reviewed to determine if coolant breach into the plasma chamber would enhance the combustion threat; for example, in-vessel steam from a water coolant breach will react with metal dust. The results of this review are presented here.

  9. Modeling internal ballistics of gas combustion guns.

    Science.gov (United States)

    Schorge, Volker; Grossjohann, Rico; Schönekess, Holger C; Herbst, Jörg; Bockholdt, Britta; Ekkernkamp, Axel; Frank, Matthias

    2016-05-01

    Potato guns are popular homemade guns which work on the principle of gas combustion. They are usually constructed for recreational rather than criminal purposes. Yet some serious injuries and fatalities due to these guns are reported. As information on the internal ballistics of homemade gas combustion-powered guns is scarce, it is the aim of this work to provide an experimental model of the internal ballistics of these devices and to investigate their basic physical parameters. A gas combustion gun was constructed with a steel tube as the main component. Gas/air mixtures of acetylene, hydrogen, and ethylene were used as propellants for discharging a 46-mm caliber test projectile. Gas pressure in the combustion chamber was captured with a piezoelectric pressure sensor. Projectile velocity was measured with a ballistic speed measurement system. The maximum gas pressure, the maximum rate of pressure rise, the time parameters of the pressure curve, and the velocity and path of the projectile through the barrel as a function of time were determined according to the pressure-time curve. The maximum gas pressure was measured to be between 1.4 bar (ethylene) and 4.5 bar (acetylene). The highest maximum rate of pressure rise was determined for hydrogen at (dp/dt)max = 607 bar/s. The muzzle energy was calculated to be between 67 J (ethylene) and 204 J (acetylene). To conclude, this work provides basic information on the internal ballistics of homemade gas combustion guns. The risk of injury to the operator or bystanders is high, because accidental explosions of the gun due to the high-pressure rise during combustion of the gas/air mixture may occur.

  10. Improvement of energy efficiency of natural gas combustion by applying a homogeneous combustion

    Directory of Open Access Journals (Sweden)

    Szymczyk Jacek

    2017-01-01

    Full Text Available In many heat devices designers and operators meet the problem of low efficiency of combustion and restricted emission standards. This process should be improved to maximize its efficiency and satisfy additional requirements as, for example, uniform temperature fieldin combustion chamber, low noise level or very low NOx emission. These requirements are satisfied by homogeneous combustion. Such combustion method is particularly attractive for the steel or glass industry or power industry based in particular on natural gas. In this paper factors, which have the biggest influence on performance of flameless combustion, are discussed, among others: momentum of fuel and oxidizer, composition of the mixture, the temperature of the inlet gases. Additionally, blind simulations of combustion in a combustion chamber of a furnace are run to assess how high is the influence of these factors individually. Numerical simulations are performed in a CFD code AVL Fire. The detailed chemical kinetics mechanism GRI-mech 3.0 is used for combustion calculations. Calculations results are correlated with experimental data. Blind simulations and experiment provide similar level of NOX emission (~6-8 ppm. Experiments showed that the effect of the addition of ethylene to fuel on emissions of NOX, CO, THC is not significant. Similarly, numerical simulations predict that influence of ethylene is negligible. CO, THC and CO2 were on a stable level across all cases. NOX emissions increases when mass flow of air and fuel increases due to higher heat release in the same volume, what results in higher temperature of combustion products. When temperature of fuel increases NOX level decreases.

  11. Nordic seminar on biomass gasification and combustion

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    The report comprises a collection of papers from a seminar arranged as a part of the Nordic Energy Research Program. The aim of this program is to strengthen the basic competence in the energy field at universities and research organizations in the Nordic countries. In the program 1991-1994 six areas are selected for cooperation such as energy and society, solid fuels, district heating, petroleum technology, bioenergy and environment, and fuel cells. The topics deal both with biomass combustion and gasification, and combustion of municipal solid waste (MSW) and refuse derived fuel (RDF). A number of 11 papers are prepared. 97 refs., 91 figs., 11 tabs.

  12. Resonance ionization detection of combustion radicals

    Energy Technology Data Exchange (ETDEWEB)

    Cool, T.A. [Cornell Univ., Ithaca, NY (United States)

    1993-12-01

    Fundamental research on the combustion of halogenated organic compounds with emphasis on reaction pathways leading to the formation of chlorinated aromatic compounds and the development of continuous emission monitoring methods will assist in DOE efforts in the management and disposal of hazardous chemical wastes. Selective laser ionization techniques are used in this laboratory for the measurement of concentration profiles of radical intermediates in the combustion of chlorinated hydrocarbon flames. A new ultrasensitive detection technique, made possible with the advent of tunable VUV laser sources, enables the selective near-threshold photoionization of all radical intermediates in premixed hydrocarbon and chlorinated hydrocarbon flames.

  13. Numerical parametric studies of spray combustion instability

    Science.gov (United States)

    Pindera, M. Z.

    1993-01-01

    A coupled numerical algorithm has been developed for studies of combustion instabilities in spray-driven liquid rocket engines. The model couples gas and liquid phase physics using the method of fractional steps. Also introduced is a novel, efficient methodology for accounting for spray formation through direct solution of liquid phase equations. Preliminary parametric studies show marked sensitivity of spray penetration and geometry to droplet diameter, considerations of liquid core, and acoustic interactions. Less sensitivity was shown to the combustion model type although more rigorous (multi-step) formulations may be needed for the differences to become apparent.

  14. Combustion in Swirling Flows: A Review

    Science.gov (United States)

    Syred, N.; Beer, J. M.

    2017-11-01

    Swirling flows have been commonly used for a number of years for the stabilization of high intensity combustion processes. In general these swirling flows are poorly understood because of their complexity. This paper describes the recent progress in understanding and using these swirling flows. The main effects of swirl are to improve flame stability as a result of the formation of toroidal recirculation zones and to reduce combustion lengths by producing high rates of entrainment of the ambient fluid and fast mixing, particularly near to the boundaries of recirculation zones.

  15. Enthalpy Calculation for Pressurized Oxy- coal Combustion

    OpenAIRE

    Weihong Wu; Jingli Huang

    2012-01-01

    Oxy-fuel combustion is recognizing one of the most promising available technologies that zero emission accomplishment may be in the offing. With coal burned under the pressure of 6MPa and oxygen-enriched conditions, the high temperature and high pressure gaseous combustion product is composed of 95% CO2 and water-vapor, with the rest of O2, N2 and so on. However, once lauded as classic approach of resolving fuel gas enthalpy calculation pertaining to ideal gas at atmospheric pressure was rest...

  16. Reaction-diffusion pulses: a combustion model

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Daniel [Grup de FIsica EstadIstica, Dept. de FIsica, Universitat Autonoma de Barcelona, E-08193 Bellaterrra (Spain); Llebot, Josep Enric [Grup de FIsica EstadIstica, Dept. de FIsica, Universitat Autonoma de Barcelona, E-08193 Bellaterrra (Spain); Fort, Joaquim [Dept. de FIsica, Univ. de Girona, Campus de Montilivi, 17071 Girona, Catalonia (Spain)

    2004-07-02

    We focus on a reaction-diffusion approach proposed recently for experiments on combustion processes, where the heat released by combustion follows first-order reaction kinetics. This case allows us to perform an exhaustive analytical study. Specifically, we obtain the exact expressions for the speed of the thermal pulses, their maximum temperature and the condition of self-sustenance. Finally, we propose two generalizations of the model, namely, the case of several reactants burning together, and that of time-delayed heat conduction. We find an excellent agreement between our analytical results and simulations.

  17. Fiber-Supported Droplet Combustion Experiment-2

    Science.gov (United States)

    Colantonio, Renato O.

    1998-01-01

    A major portion of the energy produced in the world today comes from the burning of liquid hydrocarbon fuels in the form of droplets. Understanding the fundamental physical processes involved in droplet combustion is not only important in energy production but also in propulsion, in the mitigation of combustion-generated pollution, and in the control of the fire hazards associated with handling liquid combustibles. Microgravity makes spherically symmetric combustion possible, allowing investigators to easily validate their droplet models without the complicating effects of gravity. The Fiber-Supported Droplet Combustion (FSDC-2) investigation was conducted in the Microgravity Glovebox facility of the shuttles' Spacelab during the reflight of the Microgravity Science Laboratory (MSL- 1R) on STS-94 in July 1997. FSDC-2 studied fundamental phenomena related to liquid fuel droplet combustion in air. Pure fuels and mixtures of fuels were burned as isolated single and duo droplets with and without forced air convection. FSDC-2 is sponsored by the NASA Lewis Research Center, whose researchers are working in cooperation with several investigators from industry and academia. The rate at which a droplet burns is important in many commercial applications. The classical theory of droplet burning assumes that, for an isolated, spherically symmetric, single-fuel droplet, the gas-phase combustion processes are much faster than the droplet surface regression rate and that the liquid phase is at a uniform temperature equal to the boiling point. Recent, more advanced models predict that both the liquid and gas phases are unsteady during a substantial portion of the droplet's burning history, thus affecting the instantaneous and average burning rates, and that flame radiation is a dominant mechanism that can extinguish flames in a microgravity environment. FSDC-2 has provided well-defined, symmetric droplet burning data including radiative emissions to validate these theoretical

  18. Plasma igniter for internal combustion engine

    Science.gov (United States)

    Fitzgerald, D. J.; Breshears, R. R. (Inventor)

    1978-01-01

    An igniter for the air/fuel mixture used in the cylinders of an internal combustion engine is described. A conventional spark is used to initiate the discharge of a large amount of energy stored in a capacitor. A high current discharge of the energy in the capacitor switched on by a spark discharge produces a plasma and a magnetic field. The resultant combined electromagnetic current and magnetic field force accelerates the plasma deep into the combustion chamber thereby providing an improved ignition of the air/fuel mixture in the chamber.

  19. CARS measurements in an internal combustion engine.

    Science.gov (United States)

    Stenhouse, I A; Williams, D R; Cole, J B; Swords, M D

    1979-11-15

    The first reported coherent anti-Stokes Raman scattering (CARS) experiments within the cylinder of a firing internal combustion engine are described. The feasibility of making noninvasive temperature and species measurements, with good spatial and temporal resolution, both before and after ignition has been demonstrated. Temperatures have been derived from the shape of the Q-branch vibrational spectrum of nitrogen since it is present as a major species and does not take part in combustion. Methods of overcoming such problems as were encountered are discussed.

  20. Chemical Kinetic Modeling of 2-Methylhexane Combustion

    KAUST Repository

    Mohamed, Samah Y.

    2015-03-30

    Accurate chemical kinetic combustion models of lightly branched alkanes (e.g., 2-methylalkanes) are important for investigating the combustion behavior of diesel, gasoline, and aviation fuels. Improving the fidelity of existing kinetic models is a necessity, as new experiments and advanced theories show inaccuracy in certain portions of the models. This study focuses on updating thermodynamic data and kinetic model for a gasoline surrogate fuel, 2-methylhexane, with recently published group values and rate rules. These update provides a better agreement with rapid compression machine measurements of ignition delay time, while also strengthening the fundamental basis of the model.

  1. JANNAF Combustion Subcommittee Meeting. Volume 1

    Science.gov (United States)

    Fry, Ronald S. (Editor); Gannaway, Mary T. (Editor)

    1996-01-01

    This volume, the first of four volumes, is a collection of 33 unclassified/unlimited papers which were presented at the 33rd Joint Army-Navy-NASA-Air Force (JANNAF) Combustion Subcommittee Meeting in conjunction with the Propulsion Systems Hazards at the Naval Postgraduate School, Monterey, CA. The JANNAF papers contained in this volume review airbreathing combustion measurement, performance and control; electrothermal-chemical gun experiment and modeling; liquid propellant gun experiment and modeling; solid propellant gun interior ballistics; formulation modeling and diagnostics, ignition, and gun barrel wear modeling, blast and flash; and ram, fastcore and gas generator gun propulsion concepts.

  2. Kinetic data base for combustion modeling

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, W.; Herron, J.T. [National Institute of Standards and Technology, Gaithersburg, MD (United States)

    1993-12-01

    The aim of this work is to develop a set of evaluated rate constants for use in the simulation of hydrocarbon combustion. The approach has been to begin with the small molecules and then introduce larger species with the various structural elements that can be found in all hydrocarbon fuels and decomposition products. Currently, the data base contains most of the species present in combustion systems with up to four carbon atoms. Thus, practically all the structural grouping found in aliphatic compounds have now been captured. The direction of future work is the addition of aromatic compounds to the data base.

  3. Long term profitable technique: in situ combustion

    Energy Technology Data Exchange (ETDEWEB)

    Naudin, Y.

    1980-03-01

    Onsite combustion, used for heavy petroleum, should permit the rate of recuperation of certain oil fields to be increased to 45% before the end of the century. This procedure, which has not yet been perfected and is, to large extent, still in the laboratory stage, is the object of extensive experiments in the oil fields of Suplacu and Balaria in Rumania. The IFP, which has been associated with these projects since 1969, is continuing its exhaustive laboratory tests. From an economic point of view, onsite combustion necessitates heavy investments, and the technical cost of production ranges from $5 to $15/bbl.

  4. Experiments Developed to Study Microgravity Smoldering Combustion

    Science.gov (United States)

    Vergilii, Franklin

    2001-01-01

    The overall objective of the Microgravity Smoldering Combustion (MSC) research program is to understand and predict smoldering combustion under normal and microgravity (near-zero-gravity) conditions to help prevent and control smolder-originated fires, in both environments. Smoldering is defined as a nonflaming, self-sustaining, propagating, exothermic surface reaction. If a material is sufficiently permeable, smoldering is not confined to its outer surface, but can propagate as a reaction wave through the interior of the material. The MSC program will accomplish its goals by conducting smolder experiments on the ground and in a space-based laboratory, and developing theoretical models of the process. Space-based experiments are necessary because smoldering is a very slow process and, consequently, its study in a microgravity environment requires extended periods of time that can only be achieved in space. Smoldering can occur in a variety of processes ranging from the smolder of porous insulating materials to underground coal combustion. Many materials can sustain smoldering, including wood, cloth, foams, tobacco, other dry organic materials, and charcoal. The ignition, propagation, transition to flaming, and extinction of the smolder reaction are controlled by complex, thermochemical mechanisms that are not well understood. As with many forms of combustion, gravity affects the availability of the oxidizer and the transport of heat, and therefore, the rate of combustion. The smoldering combustion of porous materials has been studied both experimentally and theoretically, usually in the context of fire safety. Smoldering encompasses a number of fundamental processes, including heat and mass transfer in a porous media; endothermic pyrolysis of combustible material; ignition, propagation, and extinction of heterogeneous exothermic reactions at the solid-gas pore interface; and the onset of gas phase reactions (flaming) from existing surface reactions. Smoldering

  5. Control de velocidad de un motor de inducción utilizando un controlador Fuzzy

    Directory of Open Access Journals (Sweden)

    Madelín Lima Álvarez

    2011-03-01

    Full Text Available Se realiza la simulación del sistema de control de velocidad del motor de inducción. Se parte del enfoquevectorial y de un sistema de coordenadas adecuado a su futura utilización, utilizando para esto el lenguaje desimulación de sistemas dinámicos Simulink. En cuanto a la simulación del método de control vectorial porcampo orientado se ha empleado el denominado método de control vectorial indirecto. El control de la velocidaddel motor se simuló utilizando un controlador Fuzzy, comparándose posteriormente estos resultados con losobtenidos mediante la utilización de un controlador PI digital.  This work carries out the simulation of speed control of induction motor. It is based on the field orientation theoryand on a system of coordinates adapted to its future use. The language that has been used for the simulation ofdynamics systems is Simulink. The indirect method of the field orientation control theory was used in themathematical analysis of the induction motor. The speed control of the induction motor was simulated using aFuzzy controller and these results were compared with those obtained by means of the use of a PI digitalcontroller.

  6. MODELO CONCEPTUAL DE UN PROYECTO DE SOFTWARE UTILIZANDO EL RAZONAMIENTO BASADO EN CASOS

    Directory of Open Access Journals (Sweden)

    Martha Delgado Dapena

    2002-10-01

    Full Text Available

    Este trabajo tiene por objetivo aprovechar el conocimiento acumulado por los diseñadores (proyectistas de software en nuevos proyectos, utilizando el razonamiento basado en casos (RBC, para obtener un modelo conceptual de UML (lenguaje de modelación unificado partiendo de una lista de requerimientos candidatos definidos por los analistas. Con esta información, de carácter preliminar, los grupos de desarrollo pueden simplificar de manera notable algunos aspectos de las fases de modelación iniciales que permitan aprovechar el trabajo y las experiencias previas y aceleren por vías probadas el proceso total de elaboración de software. En este trabajo se describen las características generales del funcionamiento de un sistema que se desarrolla en el Centro de Estudios de Ingeniería de Sistemas (CEIS, que aborda estos temas de la ingeniería de software, utilizando la técnica de inteligencia artificial de razonamiento basado en casos.

  7. Signal Processing Methods for Liquid Rocket Engine Combustion Spontaneous Stability and Rough Combustion Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Casiano, Matthew; Fischbach, Sean; Hulka, James R.

    2012-01-01

    Liquid rocket engine combustion stability assessments are traditionally broken into three categories: dynamic stability, spontaneous stability, and rough combustion. This work focuses on comparing the spontaneous stability and rough combustion assessments for several liquid engine programs. The techniques used are those developed at Marshall Space Flight Center (MSFC) for the J-2X Workhorse Gas Generator program. Stability assessment data from the Integrated Powerhead Demonstrator (IPD), FASTRAC, and Common Extensible Cryogenic Engine (CECE) programs are compared against previously processed J-2X Gas Generator data. Prior metrics for spontaneous stability assessments are updated based on the compilation of all data sets.

  8. Torrefaction of empty fruit bunches under biomass combustion gas atmosphere.

    Science.gov (United States)

    Uemura, Yoshimitsu; Sellappah, Varsheta; Trinh, Thanh Hoai; Hassan, Suhaimi; Tanoue, Ken-Ichiro

    2017-11-01

    Torrefaction of oil palm empty fruit bunches (EFB) under combustion gas atmosphere was conducted in a batch reactor at 473, 523 and 573K in order to investigate the effect of real combustion gas on torrefaction behavior. The solid mass yield of torrefaction in combustion gas was smaller than that of torrefaction in nitrogen. This may be attributed to the decomposition enhancement effect by oxygen and carbon dioxide in combustion gas. Under combustion gas atmosphere, the solid yield for torrefaction of EFB became smaller as the temperature increased. The representative products of combustion gas torrefaction were carbon dioxide and carbon monoxide (gas phase) and water, phenol and acetic acid (liquid phase). By comparing torrefaction in combustion gas with torrefaction in nitrogen gas, it was found that combustion gas can be utilized as torrefaction gas to save energy and inert gas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Improved Combustion Products Monitor for the ISS Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Compound Specific Analyzer – Combustion Products, used on the International Space Station as a warning monitor of smoldering or combustion events, is being...

  10. JANNAF 37th Combustion Subcommittee Meeting. Volume 1

    Science.gov (United States)

    Fry, Ronald S. (Editor); Gannaway, Mary T. (Editor)

    2000-01-01

    This volume, the first of two volumes is a compilation of 59 unclassified/unlimited-distribution technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 37th Combustion Subcommittee (CS) meeting held jointly with the 25th Airbreathing Propulsion Subcommittee (APS), 19th Propulsion Systems Hazards Subcommittee (PSHS), and 1st Modeling and Simulation Subcommittee (MSS) meetings. The meeting was held 13-17 November 2000 at the Naval Postgraduate School and Hyatt Regency Hotel, Monterey, California. Topics covered at the CS meeting include: a keynote address on the Future Combat Systems, and review of a new JANNAF Modeling and Simulation Subcommittee, and technical papers on gun propellant burning rate, gun tube erosion, advanced gun propulsion concepts, ETC guns, novel gun propellants; liquid, hybrid and novel propellant combustion; solid propellant combustion kinetics, GAP, ADN and RDX combustion, sandwich combustion, metal combustion, combustion instability, and motor combustion instability.

  11. Numerical investigation of the heterogeneous combustion processes of solid fuels

    OpenAIRE

    Alganash, Blaid; Paul, M. C.; Watson, Ian.A.

    2015-01-01

    Two-phase computational modelling based on the Euler–Euler was developed to investigate the heterogeneous combustion processes of biomass, in the solid carbon phase, inside a newly designed combustion chamber (Model 1). A transient simulation was carried out for a small amount of carbon powder situated in a cup which was located at the centre of the combustion chamber. A heat source was provided to initiate the combustion with the air supplied by three injection nozzles. The results show that...

  12. Design of a High Intensity Turbulent Combustion System

    Science.gov (United States)

    2015-05-01

    the product. When all the carbons in the fuel converts into carbon dioxide (CO2) and all the hydrogen forms water (H20) then the combustion process...spark plug. The detail of the experiments are described in the later chapters. Although most of the hydrocarbon combustion produces carbon dioxide (CO2...combustion of carbon monoxide with 30 steps among 11 species, methane, methanol , ethane, ethylene, and acetylene combustion with 134 steps among 30

  13. Preliminary Combustion Analysis toward Stability Estimation of Rocket Engine Combustor

    OpenAIRE

    Mizobuchi, Yasuhiro; Shimizu, Taro; Naito, Taiki; 溝渕, 泰寛; 清水, 太郎; 内藤, 大貴

    2011-01-01

    A combustion flow in a model combustor equipped with a single injector located at a non-center position of the face plate is numerically simulated to investigate the combustion oscillation driving term, so called 'Rayleigh Index term' which plays a key role when we estimate the combustion stability of rocket engine combustors. The simulation reproduces the unsteady but stabilized flame behavior and reveals the flame stabilization mechanism. The critical combustion oscillation mode, T-mode, is...

  14. Combustion chemistry - activities in the CHEK research programme

    Energy Technology Data Exchange (ETDEWEB)

    Dam-Johansen, K.; Johnsson, J.E.; Glarborg, P.; Frandsen, F.; Jensen, A.; Oestberg, M. [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Chemical Engineering

    1997-10-01

    The combustion chemistry in the oxidation of fossil fuels and biofuels determines together with mixing and heat transfer the required size of a furnace, the emission of gaseous pollutants, and the formation of ash and deposits on surfaces. This presentation describes technologies for solid fuels combustion and gives a summary of the fuels, the pollutant chemistry and the inorganic chemistry in combustion processes. Emphasis is put on the work carried out in the CHEC (Combustion and Harmful Emission Control) Research Programme. (orig.)

  15. A Combustion and Heat Transfer Model for Porous Media

    Science.gov (United States)

    1982-06-01

    combustion process in two phases. During the initial phase, combustion occurs within the porous medium. The second phase occurs when the exo- thermic ...the combustion model. Specifically, there is a change in the behavior of combustion when insulated boundaries on the porous solid are changed to...represent insulated boundaries on the porous solid (i.e., no heat loss from the porous solid to the environment). Expressions III. 51 and III. 52 provide for

  16. Traveling-Wave Thermoacoustic Engines With Internal Combustion

    Science.gov (United States)

    Weiland, Nathan Thomas; Zinn, Ben T.; Swift, Gregory William

    2004-05-11

    Thermoacoustic devices are disclosed wherein, for some embodiments, a combustion zone provides heat to a regenerator using a mean flow of compressible fluid. In other embodiments, burning of a combustible mixture within the combustion zone is pulsed in phase with the acoustic pressure oscillations to increase acoustic power output. In an example embodiment, the combustion zone and the regenerator are thermally insulated from other components within the thermoacoustic device.

  17. Fundamentals of Turbulent and Multi-Phase Combustion

    CERN Document Server

    Kuo, Kenneth Kuan-yun

    2012-01-01

    Detailed coverage of advanced combustion topics from the author of Principles of Combustion, Second Edition Turbulence, turbulent combustion, and multiphase reacting flows have become major research topics in recent decades due to their application across diverse fields, including energy, environment, propulsion, transportation, industrial safety, and nanotechnology. Most of the knowledge accumulated from this research has never been published in book form-until now. Fundamentals of Turbulent and Multiphase Combustion presents up-to-date, integrated coverage of the fundamentals of turbulence

  18. Fuel supply mechanism for an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    San Filipo, F.J.

    1989-11-21

    This patent describes a fuel supply mechanism for an internal combustion engine having a plurality of combustion chambers. It comprises: a remote reservoir adapted to contain a primary supply of fuel; means, located in said remote reservoir, for evaporating fuel in said remote reservoir into an air stream moving therethrough; and means for transporting said air stream containing such evaporated fuel from said remote reservoir directly into said combustion chambers of said internal combustion engine.

  19. Staged combustion with piston engine and turbine engine supercharger

    Science.gov (United States)

    Fischer, Larry E [Los Gatos, CA; Anderson, Brian L [Lodi, CA; O'Brien, Kevin C [San Ramon, CA

    2011-11-01

    A combustion engine method and system provides increased fuel efficiency and reduces polluting exhaust emissions by burning fuel in a two-stage combustion system. Fuel is combusted in a piston engine in a first stage producing piston engine exhaust gases. Fuel contained in the piston engine exhaust gases is combusted in a second stage turbine engine. Turbine engine exhaust gases are used to supercharge the piston engine.

  20. A Computational Study of Transverse Combustion Instability Mechanisms

    Science.gov (United States)

    2014-07-01

    Marshall Space Flight Center. References 1. Smith, D. A., Zukoski, E. E., “Combustion Instability Sustained by Unsteady Vortex Combustion,” 21st JPC ...Prediction in a Model Rocket Combustor,” 47th JPC , AIAA 2011-6030. 10. Harvazinski, M. E., Modeling Self-Excited Combustion Instabilities Using A...Instabilities,” 49th JPC , AIAA 2013-3992. 13. Smith, R., Xia, G., Anderson, W., Merkle, C. L., “Extraction of Combustion Instability Mechanisms form Detailed

  1. Knock characteristics of dual-fuel combustion in diesel engines ...

    Indian Academy of Sciences (India)

    This paper investigates the combustion knock characteristics of diesel engines running on natural gas using pilot injection as means of initiating combustion. The diesel engines knock under normal operating conditions but the knock referred to in this paper is an objectionable one. In the dual-fuel combustion process we ...

  2. 30 CFR 56.7807 - Flushing the combustion chamber.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Flushing the combustion chamber. 56.7807 Section 56.7807 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Rotary Jet Piercing Rotary Jet Piercing § 56.7807 Flushing the combustion chamber. The combustion chamber...

  3. 30 CFR 57.7807 - Flushing the combustion chamber.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Flushing the combustion chamber. 57.7807... and Rotary Jet Piercing Rotary Jet Piercing-Surface Only § 57.7807 Flushing the combustion chamber. The combustion chamber of a jet drill stem which has been sitting unoperated in a drill hole shall be...

  4. 30 CFR 57.4103 - Fueling internal combustion engines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fueling internal combustion engines. 57.4103... Prevention and Control Prohibitions/precautions/housekeeping § 57.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before refueling if the fuel tanks are integral parts of...

  5. 30 CFR 77.1105 - Internal combustion engines; fueling.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Internal combustion engines; fueling. 77.1105 Section 77.1105 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... COAL MINES Fire Protection § 77.1105 Internal combustion engines; fueling. Internal combustion engines...

  6. 30 CFR 56.4103 - Fueling internal combustion engines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fueling internal combustion engines. 56.4103... Prevention and Control Prohibitions/precautions/housekeeping § 56.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before refueling if the fuel tanks are integral parts of...

  7. Decomposition of water into highly combustible hydroxyl gas used in ...

    African Journals Online (AJOL)

    The method proposed involves the decomposition of water into highly combustible hydroxyl gas via electrolysis, which is used in internal combustion engines of electrical generators for electricity generation. The by-product obtained from combustion of this gas is water vapour and oxygen to replenish the atmosphere.

  8. Numerical investigation of spray combustion towards HITAC conditions

    NARCIS (Netherlands)

    Zhu, Shanglong

    2017-01-01

    The features of High Temperature Air Combustion (HiTAC), i.e. high-efficiency combustion processes creating a uniform temperature distribution with low NOX and CO emissions, lend itself ideally for the combustion of all sorts of "difficult” fuels, ranging from low-calorific gases such as

  9. 16 CFR 1209.7 - Test procedures for smoldering combustion.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Test procedures for smoldering combustion... for smoldering combustion. This section provides the test method for determining smoldering combustion... removable extension top extending 8±.5 cm. above the top of the smolder box shall also be provided. The...

  10. 14 CFR 25.833 - Combustion heating systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Combustion heating systems. 25.833 Section... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.833 Combustion heating systems. Combustion heaters must be approved. Pressurization ...

  11. Simultaneous identification of multi-combustion-intermediates of alkanol-air flames by femtosecond filament excitation for combustion sensing

    Science.gov (United States)

    Li, Helong; Chu, Wei; Xu, Huailiang; Cheng, Ya; Chin, See-Leang; Yamanouchi, Kaoru; Sun, Hong-Bo

    2016-01-01

    Laser filamentation produced by the propagation of intense laser pulses in flames is opening up new possibility in application to combustion diagnostics that can provide useful information on understanding combustion processes, enhancing combustion efficiency and reducing pollutant products. Here we present simultaneous identification of multiple combustion intermediates by femtosecond filament excitation for five alkanol-air flames fueled by methanol, ethanol, n-propanol, n-butanol, and n-pentanol. We experimentally demonstrate that the intensities of filament-induced photoemission signals from the combustion intermediates C, C2, CH, CN increase with the increasing number of carbons in the fuel molecules, and the signal ratios between the intermediates (CH/C, CH/C2, CN/C, CH/C2, CN/CH) are different for different alkanol combustion flames. Our observation provides a way for sensing multiple combustion components by femtosecond filament excitation in various combustion conditions that strongly depend on the fuel species. PMID:27250021

  12. Sulfur retention by ash during coal combustion. Part I. A model of char particle combustion

    Directory of Open Access Journals (Sweden)

    BORISLAV GRUBOR

    2003-02-01

    Full Text Available A model for the combustion of porous char particles as a basis for modeling the process of sulfur retention by ash during coal combustion is developed in this paper. The model belongs to the microscopic intrinsic models and describes the dynamic behavior of a porous char particle during comustion, taking into account temporal and spatial changes of all important physical properties of the char particle and various combustion parameters. The parametric analysis of the enhanced model shows that the model represents a good basis for the development of a model for the process of sulfur retention by ash during coal combustion. The model enables the prediction of the values of all parameters necessary for the introduction of reactions between sulfur compounds and mineral components in ash, primarily calcium oxide.

  13. Combustion Velocity of Benzine-Benzol-Air Mixtures in High-Speed Internal-Combustion Engines

    Science.gov (United States)

    Schnauffer, Kurt

    1932-01-01

    The present paper describes a device whereby rapid flame movement within an internal-combustion engine cylinder may be recorded and determined. By the aid of a simple cylindrical contact and an oscillograph the rate of combustion within the cylinder of an airplane engine during its normal operation may be measured for gas intake velocities of from 30 to 35 m/s and for velocities within the cylinder of from 20 to 25 m/s. With it the influence of mixture ratios, of turbulence, of compression ratio and kind of fuel on combustion velocity may be determined. Besides the determination of the influence of the above factors on combustion velocity, the degree of turbulence may also be determined. As a unit of reference in estimating the degree of turbulence, the intake velocity of the charge is chosen.

  14. Oxy-fuel combustion of pulverized fuels

    DEFF Research Database (Denmark)

    Yin, Chungen; Yan, Jinyue

    2016-01-01

    Oxy-fuel combustion of pulverized fuels (PF), as a promising technology for CO2 capture from power plants, has gained a lot of concerns and also advanced considerable research, development and demonstration in the last past years worldwide. The use of CO2 or the mixture of CO2 and H2O vapor as th...

  15. deNOx catalysts for biomass combustion

    DEFF Research Database (Denmark)

    Kristensen, Steffen Buus

    The present thesis revolves around the challenges involved in removal of nitrogen oxides in biomass fired power plants. Nitrogen oxides are unwanted byproducts formed to some extent during almost any combustion. In coal fired plants these byproducts are removed by selective catalytic reduction...

  16. Straw Combustion in a Grate Furnace

    DEFF Research Database (Denmark)

    Lans, Robert Pieter Van Der

    1998-01-01

    Fixed-bed combustion of straw has been conducted in a 15 cm diameter and 137 cm long cylindrical reactor. Air, which could be preheated, was introduced through the bottom plate. The straw was ignited at the top with a radiation heater. After ignition, when a self-sustaining reaction front...

  17. Combustion: an oil spill mitigation tool

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-11-01

    The technical feasibility of using combustion as an oil spill mitigation tool was studied. Part I of the two-part report is a practical guide oriented toward the needs of potential users, while Part II is the research or resource document from which the practical guidance was drawn. The study included theoretical evaluations of combustion of petroleum pool fires under the effects of weathering and an oil classification system related to combustion potential. The theoretical analysis of combustion is balanced by practical experience of oil burning and case history information. Decision elements are provided which can be used as a guide for technical evaluations of a particular oil spill situation. The rationale for assessing technical feasibility is given in the context of other alternatives available for response to an oil spill. A series of research and technology development concepts are included for future research. The ethics of using oil burning are discussed as issues, concerns, and tradeoffs. A detailed annotated bibliography is appended along with a capsule review of a decade of oil burning studies and other support information.

  18. CloudFlame: Cyberinfrastructure for combustion research

    KAUST Repository

    Goteng, Gokop

    2013-12-01

    Combustion experiments and chemical kinetics simulations generate huge data that is computationally and data intensive. A cloud-based cyber infrastructure known as Cloud Flame is implemented to improve the computational efficiency, scalability and availability of data for combustion research. The architecture consists of an application layer, a communication layer and distributed cloud servers running in a mix environment of Windows, Macintosh and Linux systems. The application layer runs software such as CHEMKIN modeling application. The communication layer provides secure transfer/archive of kinetic, thermodynamic, transport and gas surface data using private/public keys between clients and cloud servers. A robust XML schema based on the Process Informatics Model (Prime) combined with a workflow methodology for digitizing, verifying and uploading data from scientific graphs/tables to Prime is implemented for chemical molecular structures of compounds. The outcome of using this system by combustion researchers at King Abdullah University of Science and Technology (KAUST) Clean Combustion Research Center and its collaborating partners indicated a significant improvement in efficiency in terms of speed of chemical kinetics and accuracy in searching for the right chemical kinetic data.

  19. The PDF method for turbulent combustion

    Science.gov (United States)

    Pope, S. B.

    1991-01-01

    Probability Density Function (PDF) methods provide a means of calculating the properties of turbulent reacting flows. They have been successfully applied to many turbulent flames, including some with finite rate kinetic effects. Here the methods are reviewed with an emphasis on computational issues and their application to turbulent combustion.

  20. Combustion properties of wood impregnated with commercial ...

    African Journals Online (AJOL)

    The objective of this study was to determine some combustion properties of Calabrian pine (Pinus brutia Ten.) wood specimens impregnated with aqueous solutions of commercial fertilizers. Ammonium sulphate (AS) and diammonium phosphate (DAP) were used as commercial fertilizers. Diammonium phosphate and ...

  1. Gasoline Combustion Fundamentals DOE FY17 Report

    Energy Technology Data Exchange (ETDEWEB)

    Ekoto, Isaac W. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2017-11-01

    Advanced automotive gasoline engines that leverage a combination of reduced heat transfer, throttling, and mechanical losses; shorter combustion durations; and higher compression and mixture specific heat ratios are needed to meet aggressive DOE VTP fuel economy and pollutant emission targets. Central challenges include poor combustion stability at low-power conditions when large amounts of charge dilution are introduced and high sensitivity of conventional inductive coil ignition systems to elevated charge motion and density for boosted high-load operation. For conventional spark ignited operation, novel low-temperature plasma (LTP) or pre-chamber based ignition systems can improve dilution tolerances while maintaining good performance characteristics at elevated charge densities. Moreover, these igniters can improve the control of advanced compression ignition (ACI) strategies for gasoline at low to moderate loads. The overarching research objective of the Gasoline Combustion Fundamentals project is to investigate phenomenological aspects related to enhanced ignition. The objective is accomplished through targeted experiments performed in a single-cylinder optically accessible research engine or an in-house developed optically accessible spark calorimeter (OASC). In situ optical diagnostics and ex situ gas sampling measurements are performed to elucidate important details of ignition and combustion processes. Measurements are further used to develop and validate complementary high-fidelity ignition simulations. The primary project audience is automotive manufacturers, Tier 1 suppliers, and technology startups—close cooperation has resulted in the development and execution of project objectives that address crucial mid- to long-range research challenges.

  2. Controlling spontaneous combustion in surface coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Eroglu, N.

    2005-07-01

    The Witbank Coalfield in South Africa has historically been mined out using the bord-and-pillar method, with typically low coal-recovery ratios, leaving significant amounts of coal in pillars and as floor and roof coal. These pillars are being re-extracted by underground and surface mining methods. During surface mining, air enters through the cracks and bords into the old workings, causing spontaneous combustion of coal. Over the long term, air will also enter the old underground bord-and-pillar workings at shallow depth through sinkholes caused by bord collapse underground. The resulting environmental problems may necessitate future rehabilitation at great cost. Existing knowledge about spontaneous combustion in opencast collieries indicates that there is no typical fire and certainly no standard technique for preventing it from happening. However, with current measures it is possible to control the spontaneous combustion of coal in opencast collieries. A project supported by Coaltech 2020, a South African coal mining Collaborative Research Programme, has been completed to develop methods for minimising and controlling spontaneous combustion in old workings by surface mining methods and applications. However, the findings and recommendations of this study, which focused on the Witbank Coalfield, can be adapted to other surface coal mines. 11 figs.

  3. Fluidized-bed combustion reduces atmospheric pollutants

    Science.gov (United States)

    Jonke, A. A.

    1972-01-01

    Method of reducing sulfur and nitrogen oxides released during combustion of fossil fuels is described. Fuel is burned in fluidized bed of solids with simultaneous feeding of crushed or pulverized limestone to control emission. Process also offers high heat transfer rates and efficient contacting for gas-solid reactions.

  4. Detonation capturing for stiff combustion chemistry

    NARCIS (Netherlands)

    Berkenbosch, A.C.; Kaasschieter, E.F.; Klein, R.

    1998-01-01

    This paper contributes to the topic of unphysical one-cell-per-time-step travelling combustion wave solutions in numerical computations of detonation waves in the presence of stiff chemical source terms. These false weak detonation solutions appear when a gas-dynamics-chemistry operator-splitting

  5. Starting apparatus for internal combustion engines

    Science.gov (United States)

    Dyches, G.M.; Dudar, A.M.

    1995-01-01

    This report is a patent description for a system to start an internal combustion engine. Remote starting and starting by hearing impaired persons are addressed. The system monitors the amount of current being drawn by the starter motor to determine when the engine is started. When the engine is started the system automatically deactivates the starter motor. Five figures are included.

  6. Combustion synthesis and preliminary luminescence studies of ...

    Indian Academy of Sciences (India)

    The polycrystalline sample of LiBaPO4 : Tb3+ (LBPT) was successfully synthesized by solution combustion synthesis and studied for its luminescence characteristics. The thermoluminescence (TL) glow curve of LBPT material consists of two peaks at 204.54 and 251.21°C. The optimum concentration was 0.005 mol to ...

  7. Effects of combustible stacking in large compartments

    DEFF Research Database (Denmark)

    Gentili, Filippo; Giuliani, Luisa; Bontempi, Franco

    2013-01-01

    of non uniform distribution of the combustible materials and fire propagation. These aspects are discussed in this paper with reference to an industrial steel building, taken as case study. Fires triggered by the burning of wooden pallets stored in the premises have been investigated with respect...

  8. Combustion Power Unit--400: CPU-400.

    Science.gov (United States)

    Combustion Power Co., Palo Alto, CA.

    Aerospace technology may have led to a unique basic unit for processing solid wastes and controlling pollution. The Combustion Power Unit--400 (CPU-400) is designed as a turboelectric generator plant that will use municipal solid wastes as fuel. The baseline configuration is a modular unit that is designed to utilize 400 tons of refuse per day…

  9. Advanced Fuels and Combustion Processes for Propulsion

    Science.gov (United States)

    2010-09-01

    production from biomass steam reforming – Conduct a feasibility analysis of the proposed integrated process Energia Technologies - D. Nguyen & K. Parimi...strength foam material development by Ultramet – Combustion experiments performed U. Of Alabama – End-user input provided by Solar Turbines Major

  10. Evaluation of thermal characteristics of oscillating combustion ...

    African Journals Online (AJOL)

    The results when compared to the conventional combustion led to low fuel and specific energy consumption, enhanced heat transfer rate, increased furnace efficiency with visibly low volumes of flue gases with reduced emissions. The increased heat transfer rate and furnace efficiency was found to be in agreement with the ...

  11. Fractal turbulence enhancing low-swirl combustion

    NARCIS (Netherlands)

    Verbeek, Antonie Alex; Bouten, Thijs W.F.M.; Stoffels, Genie G.M.; Geurts, Bernardus J.; van der Meer, Theodorus H.

    The use of fractal grids in a low-swirl burner can significantly increase the turbulent combustion rate, realizing a higher power density in these flames. The standard turbulence generating blocking grid has been replaced by one consisting of a pattern of cruciform structures of different sizes,

  12. Turbine Burners: Turbulent Combustion of Liquids Fuels

    Science.gov (United States)

    2009-09-14

    stabilized combustion facility on liquid fuel adds another level of complex- ity because the fuel must first vaporize before it can mix into the air supply...vortex of the size of the cavity was entrained in a cavity of aspect ratio 1. This vortex was seen using multiple imaging techniques. (b) Schlieren

  13. Simulation of lean premixed turbulent combustion

    Energy Technology Data Exchange (ETDEWEB)

    Bell, John B.; Day, Marcus S.; Almgren, Ann S.; Lijewski, MichaelJ.; Rendleman, Charles A.; Cheng, Robert K.; Shepherd, Ian G.

    2006-06-25

    There is considerable technological interest in developingnew fuel-flexible combustion systems that can burn fuels such ashydrogenor syngas. Lean premixed systems have the potential to burn thesetypes of fuels with high efficiency and low NOx emissions due to reducedburnt gas temperatures. Although traditional scientific approaches basedon theory and laboratory experiment have played essential roles indeveloping our current understanding of premixed combustion, they areunable to meet the challenges of designing fuel-flexible lean premixedcombustion devices. Computation, with itsability to deal with complexityand its unlimited access to data, hasthe potential for addressing thesechallenges. Realizing this potential requires the ability to perform highfidelity simulations of turbulent lean premixed flames under realisticconditions. In this paper, we examine the specialized mathematicalstructure of these combustion problems and discuss simulation approachesthat exploit this structure. Using these ideas we can dramatically reducecomputational cost, making it possible to perform high-fidelitysimulations of realistic flames. We illustrate this methodology byconsidering ultra-lean hydrogen flames and discuss how this type ofsimulation is changing the way researchers study combustion.

  14. Co-combustion: A summary of technology

    Directory of Open Access Journals (Sweden)

    Leckner Bo

    2007-01-01

    Full Text Available Co-combustion of biomass or waste together with a base fuel in a boiler is a simple and economically suitable way to replace fossil fuels by biomass and to utilize waste. Co-combustion in a high-efficiency power station means utilization of biomass and waste with a higher thermal efficiency than what otherwise had been possible. Due to transport limitations, the additional fuel will only supply a minor part (less than a few hundreds MW fuel of the energy in a plant. There are several options: co-combustion with coal in pulverized or fluidized bed boilers, combustion on added grates inserted in pulverized coal boilers, combustors for added fuel coupled in parallel to the steam circuit of a power plant, external gas producers delivering its gas to replace an oil, gas or pulverized fuel burner. Furthermore biomass can be used for reburning in order to reduce NO emissions or for afterburning to reduce N2O emissions in fluidized bed boilers. Combination of fuels can give rise to positive or negative synergy effects, of which the best known are the interactions between S, Cl, K, Al, and Si that may give rise to or prevent deposits on tubes or on catalyst surfaces, or that may have an influence on the formation of dioxins. With better knowledge of these effects the positive ones can be utilized and the negative ones can be avoided.

  15. Combustion synthesis of cadmium sulphide nanomaterials for ...

    Indian Academy of Sciences (India)

    The observed enhanced photocatalytic activity of the CdS nanomaterials for the hydrogen production from water (2120 μmol/h) can be attributed to high crystallinity, low band gap and less exciton recombination due to the C and N doping. Keywords. Cadmium sulphide; combustion synthesis; anion doping; water splitting; ...

  16. GRCop-84 Development for Combustion Chamber Liners

    Science.gov (United States)

    Ellis, David; Nathal, Michael; Yun, Hee Man; Lerch, Bradley; Greenbauer-Seng, Leslie; Thomas-Ogbuji, Linus; Holmes, Richard

    2000-01-01

    The development, test, and thermophysical & mechanical properties of a GRCop-84 alloy for combustion chamber liners is discussed. Topics discussed include: History of GRCop-84 development, GRCop-84 thermal expansion, thermal conductivity of GRCop-84, yield strength of GRCop-84, GRCop-84 creep lives, GrCop-84 low cycle fatigue (LCF) lives, and hot fire testing of GRCop-84 spool pieces.

  17. Coal combustion and air pollution control

    Energy Technology Data Exchange (ETDEWEB)

    Sedlacek, J.

    1987-07-01

    Briefly describes the general problem of emissions from fossil-fuel combustion and compares the effects of burning brown coal and those of using heating oil. Describes methods selected for desulfurization in Czechoslovakia based on the magnesite method. Raw materials for this method are available in the country and the processes have been tested in the USSR. The first installation is under construction on a 200 MW unit of an electricity plant in North Bohemia. Briefly describes this system, which involves cooling and humidifying combustion products before they enter a scrubber to be passed over sulfur dioxide magnesium oxide, which converts the sulfur dioxide to produce magnesium sulfite crystals, which are then converted by fluidized-bed combustion at 900-950 C back to sulfur dioxide and magnesium oxide. The sulfur dioxide is used for manufacturing sulfuric acid and the magnesium oxide is recycled through the system. Discusses in general terms future possibilities for dealing with combustion products, including semi-dry, wet, calcium chloride, limestone, RCE (Refractories Consulting and Engineering, GmbH, FRG) and citrate methods, and briefly examines the economic aspects involved. 12 refs.

  18. Combustion synthesis of graphene and ultracapacitor performance

    Indian Academy of Sciences (India)

    Graphene sheets are synthesized by a simple method starting from graphitic oxide as a precursor. Reaction of graphitic oxide at 250 °C with a combustion mixture of urea and ammonium nitrate results in the formation of thin graphene sheets. Graphene formation is characterized by XRD, TGA, XPS and TEM. Graphene ...

  19. Simulation Of The Internal-Combustion Engine

    Science.gov (United States)

    Zeleznik, Frank J.; Mcbride, Bonnie J.

    1987-01-01

    Program adapts to available information about particular engine. Mathematical model of internal-combustion engine constructed and implemented as computer program suitable for use on large digital computer systems. ZMOTTO program calculates Otto-cycle performance parameters as well as working-fluid compositions and properties throughout cycle for number of consecutive cycles and for variety of input parameters. Written in standard FORTRAN IV.

  20. Cars beyond Otto's Internal Combustion Engines

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 11. Cars Beyond Otto's Internal Combustion Engines. A K Shukla. General Article Volume 6 Issue 11 November 2001 pp 49-62. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/006/11/0049-0062 ...

  1. Column leaching from biomass combustion ashes

    DEFF Research Database (Denmark)

    Maresca, Alberto; Astrup, Thomas Fruergaard

    2015-01-01

    The utilization of biomass combustion ashes for forest soil liming and fertilizing has been addressed in literature. Though, a deep understanding of the ash chemical composition and leaching behavior is necessary to predict potential benefits and environmental risks related to this practice...

  2. Hydrogen-oxygen powered internal combustion engine

    Science.gov (United States)

    Cameron, H.; Morgan, N.

    1970-01-01

    Hydrogen at 300 psi and oxygen at 800 psi are injected sequentially into the combustion chamber to form hydrogen-rich mixture. This mode of injection eliminates difficulties of preignition, detonation, etc., encountered with carburated, spark-ignited, hydrogen-air mixtures. Ignition at startup is by means of a palladium catalyst.

  3. Comparing maximum pressures in internal combustion engines

    Science.gov (United States)

    Sparrow, Stanwood W; Lee, Stephen M

    1922-01-01

    Thin metal diaphragms form a satisfactory means for comparing maximum pressures in internal combustion engines. The diaphragm is clamped between two metal washers in a spark plug shell and its thickness is chosen such that, when subjected to explosion pressure, the exposed portion will be sheared from the rim in a short time.

  4. IMPROVED COMBUSTION PROCESSES IN MEDICAL WASTES ...

    African Journals Online (AJOL)

    IMPROVED COMBUSTION PROCESSES IN MEDICAL WASTES INCINERATORS FOR RURAL APPLICATIONS. ... African Journal of Science and Technology ... In particular, the demand for health services has increased to an extent that the health sector produces large quantities of biomedical wastes that can have severe ...

  5. Experimental toxicology of pyrolysis and combustion hazards.

    Science.gov (United States)

    Cornish, H H; Hahn, K J; Barth, M L

    1975-01-01

    Data are presented on the acute toxicity (mortality only) of the thermal degradation products of polymers obtained by two methods of degradation. One system utilized a slowly increasing temperature (5 degrees C/min) and gradual degradation of the polymer with the rats being exposed to degradation products as they were evolved. In this system the more toxic polymers included wool, polypropylene, poly(vinyl chloride), and urethane foam. The second system utilized conditions of rapid combustion and exposure of rats to the total products of combustion for a period of 4 hr. In this system the more toxic materials included red oak, cotton, acrylonitrile-butadiene-styrene (ABS), and styrene-acrylonitrile. It is of interest to note that the natural product wool is among the least toxic under these rapid combustion conditions and among the most toxic under slow pyrolysis conditions. Other materials also vary in the comparative toxicity of their thermal degradation products, depending upon the conditions of degradation and animal exposure. The two experimental techniques presented here may well represent the two extreme conditions of rapid combustion versus slow pyrolysis. Intermediate types of fire situations might be expected to result in relative acute toxicities somewhere between these two extremes. This report deals with acute toxicity on the basis of mortality data only and does not include other parameters of toxicity such as organ weights and histopathology. PMID:1175552

  6. Burning characteristics of microcellular combustible objects

    Directory of Open Access Journals (Sweden)

    Wei-tao Yang

    2014-06-01

    Full Text Available Microcellular combustible objects for application of combustible case, caseless ammunition or combustible detonator-holding tubes are fabricated through one-step foaming process, in which supercritical CO2 is used as foaming agent. The formulations consist of inert polymer binder and ultra fine RDX. For the inner porous structures of microcellular combustible objects, the cell sizes present a unimodal or bimodal distribution by adjusting the foaming conditions. Closed bomb test is to investigate the influence of both porous structure style and RDX content on burning behavior. The sample with bimodal distribution of cell sizes burns faster than that with unimodal distribution, and the concentration of RDX can influence the burning characteristics in a positive manner. In addition, the translation of laminar burning to convective burning is determined by burning rate versus pressure curves of samples at two different loading densities, and the resulting transition pressure is 30 MPa. Moreover, the samples with bigger sample size present higher burning rate, resulting in providing deeper convective depth. Dynamic vivacity of samples is also studied. The results show that the vivacity increases with RDX content and varies with inner structure.

  7. A model for premixed combustion oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Janus, M.C.; Richards, G.A.

    1996-03-01

    Combustion oscillations are receiving renewed research interest due to increasing application of lean premix (LPM) combustion to gas turbines. A simple, nonlinear model for premixed combustion is described; it was developed to explain experimental results and to provide guidance for developing active control schemes based on nonlinear concepts. The model can be used to quickly examine instability trends associated with changes in equivalence ratio, mass flow rate, geometry, ambient conditions, etc. The model represents the relevant processes occurring in a fuel nozzle and combustor analogous to current LPM turbine combustors. Conservation equations for the nozzle and combustor are developed from simple control volume analysis, providing ordinary differential equations that can be solved on a PC. Combustion is modeled as a stirred reactor, with bimolecular reaction between fuel and air. Although focus is on the model, it and experimental results are compared to understand effects of inlet air temperature and open loop control schemes. The model shows that both are related to changes in transport time.

  8. ANALYSIS OF INTERNAL COMBUSTION ENGINE WITH A NEW CONCEPT OF POROUS MEDIUM COMBUSTION FOR THE FUTURE CLEAN ENGINE

    OpenAIRE

    Ashok A Dhale; Awari,Gajanan K.; Singh, Mahendra P.

    2010-01-01

    At present, the emissions of internal combustion engine can only be improved by catalytic treatments of the exhaust gases. Such treatments, however, result in high costs and relatively low conversion efficiency. This suggests that a new combustion technique should be developed to yield improved primary combustion processes inside the engine with drastically reduced exhaust gas emissions. To fulfill all requirements, Dr. Franz Drust has proposed a new combustion concept to perform homogenous c...

  9. Oxy-Combustion Boiler Material Development

    Energy Technology Data Exchange (ETDEWEB)

    Gagliano, Michael; Seltzer, Andrew; Agarwal, Hans; Robertson, Archie; Wang, Lun

    2012-01-31

    Under U.S. Department of Energy Cooperative Agreement No. DE-NT0005262 Foster Wheeler North America Corp conducted a laboratory test program to determine the effect of oxy-combustion on boiler tube corrosion. In this program, CFD modeling was used to predict the gas compositions that will exist throughout and along the walls of air-fired and oxy-fired boilers operating with low to high sulfur coals. Test coupons of boiler tube materials were coated with deposits representative of those coals and exposed to the CFD predicted flue gases for up to 1000 hours. The tests were conducted in electric tube furnaces using oxy-combustion and air-fired flue gases synthesized from pressurized cylinders. Following exposure, the test coupons were evaluated to determine the total metal wastage experienced under air and oxy-combustions conditions and materials recommendations were made. Similar to air-fired operation, oxy-combustion corrosion rates were found to vary with the boiler material, test temperature, deposit composition, and gas composition. Despite this, comparison of air-fired and oxy-fired corrosion rates showed that oxy-firing rates were, for the most part, similar to, if not lower than those of air-firing; this finding applied to the seven furnace waterwall materials (wrought and weld overlay) and the ten superheater/reheater materials (wrought and weld overlay) that were tested. The results of the laboratory oxy-combustion tests, which are based on a maximum bulk flue gas SO2 level of 3200 ppmv (wet) / 4050 ppmv (dry), suggest that, from a corrosion standpoint, the materials used in conventional subcritical and supercritical, air-fired boilers should also be suitable for oxy-combustion retrofits. Although the laboratory test results are encouraging, they are only the first step of a material evaluation process and it is recommended that follow-on corrosion tests be conducted in coal-fired boilers operating under oxy-combustion to provide longer term (one to two year

  10. Oxy-Combustion Boiler Material Development

    Energy Technology Data Exchange (ETDEWEB)

    Michael Gagliano; Andrew Seltzer; Hans Agarwal; Archie Robertson; Lun Wang

    2012-01-31

    Under U.S. Department of Energy Cooperative Agreement No. DE-NT0005262 Foster Wheeler North America Corp conducted a laboratory test program to determine the effect of oxy-combustion on boiler tube corrosion. In this program, CFD modeling was used to predict the gas compositions that will exist throughout and along the walls of air-fired and oxy-fired boilers operating with low to high sulfur coals. Test coupons of boiler tube materials were coated with deposits representative of those coals and exposed to the CFD predicted flue gases for up to 1000 hours. The tests were conducted in electric tube furnaces using oxy-combustion and air-fired flue gases synthesized from pressurized cylinders. Following exposure, the test coupons were evaluated to determine the total metal wastage experienced under air and oxy-combustions conditions and materials recommendations were made. Similar to air-fired operation, oxy-combustion corrosion rates were found to vary with the boiler material, test temperature, deposit composition, and gas composition. Despite this, comparison of air-fired and oxy-fired corrosion rates showed that oxy-firing rates were, for the most part, similar to, if not lower than those of air-firing; this finding applied to the seven furnace waterwall materials (wrought and weld overlay) and the ten superheater/reheater materials (wrought and weld overlay) that were tested. The results of the laboratory oxy-combustion tests, which are based on a maximum bulk flue gas SO{sub 2} level of 3200 ppmv (wet) / 4050 ppmv (dry), suggest that, from a corrosion standpoint, the materials used in conventional subcritical and supercritical, air-fired boilers should also be suitable for oxy-combustion retrofits. Although the laboratory test results are encouraging, they are only the first step of a material evaluation process and it is recommended that follow-on corrosion tests be conducted in coal-fired boilers operating under oxy-combustion to provide longer term (one to

  11. NOx Emission Reduction by Oscillating Combustion

    Energy Technology Data Exchange (ETDEWEB)

    John C. Wagner

    2004-03-31

    High-temperature, natural gas-fired furnaces, especially those fired with preheated air, produce large quantities of NO{sub x} per ton of material processed. Regulations on emissions from industrial furnaces are becoming increasingly more stringent. In addition, competition is forcing operators to make their furnaces more productive and/or efficient. Switching from preheated air to industrial oxygen can increase efficiency and reduce NO{sub x}, but oxygen is significantly more costly than air and may not be compatible with the material being heated. What was needed, and what was developed during this project, is a technology that reduces NO{sub x} emissions while increasing furnace efficiency for both air- and oxy-fired furnaces. Oscillating combustion is a retrofit technology that involves the forced oscillation of the fuel flow rate to a furnace. These oscillations create successive, fuel-rich and fuel-lean zones within the furnace. Heat transfer from the flame to the load increases due to the more luminous fuel-rich zones, a longer overall flame length, and the breakup of the thermal boundary layer. The increased heat transfer shortens heat up times, thereby increasing furnace productivity, and reduces the heat going up the stack, thereby increasing efficiency. The fuel-rich and fuel-lean zones also produce substantially less NO{sub x} than firing at a constant excess air level. The longer flames and higher heat transfer rate reduces overall peak flame temperature and thus reduces additional NO{sub x} formation from the eventual mixing of the zones and burnout of combustibles from the rich zones. This project involved the development of hardware to implement oscillating combustion on an industrial scale, the laboratory testing of oscillating combustion on various types of industrial burners, and the field testing of oscillating combustion on several types of industrial furnace. Before laboratory testing began, a market study was conducted, based on the

  12. NOx Emission Reduction by Oscillating combustion

    Energy Technology Data Exchange (ETDEWEB)

    Institute of Gas Technology

    2004-01-30

    High-temperature, natural gas-fired furnaces, especially those fired with preheated air, produce large quantities of NO{sub x} per ton of material processed. Regulations on emissions from industrial furnaces are becoming increasingly more stringent. In addition, competition is forcing operators to make their furnaces more productive and/or efficient. Switching from preheated air to industrial oxygen can increase efficiency and reduce NO{sub x}, but oxygen is significantly more costly than air and may not be compatible with the material being heated. What was needed, and what was developed during this project, is a technology that reduces NO{sub x} emissions while increasing furnace efficiency for both air- and oxy-fired furnaces. Oscillating combustion is a retrofit technology that involves the forced oscillation of the fuel flow rate to a furnace. These oscillations create successive, fuel-rich and fuel-lean zones within the furnace. Heat transfer from the flame to the load increases due to the more luminous fuel-rich zones, a longer overall flame length, and the breakup of the thermal boundary layer. The increased heat transfer shortens heat up times, thereby increasing furnace productivity, and reduces the heat going up the stack, thereby increasing efficiency. The fuel-rich and fuel-lean zones also produce substantially less NO{sub x} than firing at a constant excess air level. The longer flames and higher heat transfer rate reduces overall peak flame temperature and thus reduces additional NO{sub x} formation from the eventual mixing of the zones and burnout of combustibles from the rich zones. This project involved the development of hardware to implement oscillating combustion on an industrial scale, the laboratory testing of oscillating combustion on various types of industrial burners, and the field testing of oscillating combustion on several types of industrial furnace. Before laboratory testing began, a market study was conducted, based on the

  13. Fuel Chemistry And Combustion Distribution Effects On Rocket Engine Combustion Stability

    Science.gov (United States)

    2015-11-19

    AFRL-AFOSR-VA-TR-2016-0014 Effects of Increased Energy and Particulate Damping on Rocket William. Anderson PURDUE UNIVERSITY Final Report 11/19/2015...Distribution Effects On Rocket Engine Combustion Stability 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9550-10-1-0431 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...addition can be used to alter the combustion instability characteristics of liquid rocket engines. Fuels with increased energy, either due to higher heats

  14. The Multi-User Droplet Combustion Apparatus: the Development and Integration Concept for Droplet Combustion Payloads in the Fluids and Combustion Facility Combustion Integrated Rack

    Science.gov (United States)

    Myhre, C. A.

    2002-01-01

    The Multi-user Droplet Combustion Apparatus (MDCA) is a multi-user facility designed to accommodate four different droplet combustion science experiments. The MDCA will conduct experiments using the Combustion Integrated Rack (CIR) of the NASA Glenn Research Center's Fluids and Combustion Facility (FCF). The payload is planned for the International Space Station. The MDCA, in conjunction with the CIR, will allow for cost effective extended access to the microgravity environment, not possible on previous space flights. It is currently in the Engineering Model build phase with a planned flight launch with CIR in 2004. This paper provides an overview of the capabilities and development status of the MDCA. The MDCA contains the hardware and software required to conduct unique droplet combustion experiments in space. It consists of a Chamber Insert Assembly, an Avionics Package, and a multiple array of diagnostics. Its modular approach permits on-orbit changes for accommodating different fuels, fuel flow rates, soot sampling mechanisms, and varying droplet support and translation mechanisms to accommodate multiple investigations. Unique diagnostic measurement capabilities for each investigation are also provided. Additional hardware provided by the CIR facility includes the structural support, a combustion chamber, utilities for the avionics and diagnostic packages, and the fuel mixing capability for PI specific combustion chamber environments. Common diagnostics provided by the CIR will also be utilized by the MDCA. Single combustible fuel droplets of varying sizes, freely deployed or supported by a tether are planned for study using the MDCA. Such research supports how liquid-fuel-droplets ignite, spread, and extinguish under quiescent microgravity conditions. This understanding will help us develop more efficient energy production and propulsion systems on Earth and in space, deal better with combustion generated pollution, and address fire hazards associated with

  15. Red de Investigación en Sistemas Inteligentes. Evaluación continua mediante controles utilizando Moodle

    OpenAIRE

    Aznar Gregori, Fidel; Compañ, Patricia; Pujol, Mar; Rizo, Ramón; Tortosa Sempere, Mireia Luisa; Viejo Hernando, Diego; Varela Rizo, Santiago

    2015-01-01

    Esta memoria corresponde al trabajo desarrollado durante el curso 2013-2014 por los componentes de la “Red de Investigación en Sistemas Inteligentes. Evaluación continua mediante controles utilizando Moodle”. Código de Red ICE: 3021. En la asignatura Sistemas Inteligentes del grado en Ingeniería Informática, durante el curso 2013-14, se planteó a los estudiantes un sistema de evaluación continua de la parte teórica consistente en la realización de controles on-line utilizando cuestionarios Mo...

  16. Implementação do logon do gerenciamento de contexto utilizando CORBA sobre TCP/IP.

    OpenAIRE

    Érico Neves de Souza

    2002-01-01

    O principal objetivo deste trabalho é modelar e implementar a aplicação de Gerenciamento de Contexto, padronizada pela ICAO, utilizando um sistema baseado na arquitetura Common Object Request Broker Architecture (CORBA) para disponibilizar as aplicações que um aeroporto pode oferecer para um avião. Através do uso da Unified Modeling Language (UML) é demonstrado o processo de modelagem do software, utilizando uma abordagem orientada a objetos. Neste trabalho ainda é feita uma descrição do CORB...

  17. Modification of combustion aerosols in the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Weingartner, E. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1996-07-01

    Combustion aerosols particles are released on large scale into the atmosphere in the industrialized regions as well as in the tropics (by wood fires). The particles are subjected to various aging processes which depend on the size, morphology, and chemical composition of the particles. The interaction of combustion particles with sunlight and humidity as well as adsorption and desorption of volatile material to or from the particles considerably changes their physical and chemical properties and thus their residence time in the atmosphere. This is of importance because combustion particles are known to have a variety of health effects on people. Moreover, atmospheric aerosol particles have an influence on climate, directly through the reflection and absorption of solar radiation and indirectly through modifying the optical properties and lifetime of clouds. In a first step, a field experiment was carried out to study the sources and characteristics of combustion aerosols that are emitted from vehicles in a road tunnel. It was found that most of the fine particles were tail pipe emissions of diesel powered vehicles. The calculation shows that on an average these vehicles emit about 300 mg fine particulate matter per driven kilometer. This emission factor is at least 100 times higher than the mean emission factor estimated for gasoline powered vehicles. Furthermore, it is found that during their residence time in the tunnel, the particles undergo significant changes: The particles change towards a more compact structure. The conclusion is reached that this is mainly due to adsorption of volatile material from the gas phase to the particle surface. In the atmosphere, the life cycle as well as the radiative and chemical properties of an aerosol particle is strongly dependent on its response to humidity. Therefore the hygroscopic behavior of combustion particles emitted from single sources (i.e. from a gasoline and a diesel engine) were studied in laboratory experiments.

  18. Combustive management of oil spills. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-01

    Extensive experiments with in situ incineration were performed on a desert site at the University of Arizona with very striking results. The largest incinerator, 6 feet in diameter with a 30 foot chimney, developed combustion temperatures of 3000, F, and attendant soot production approximately 1000 times less than that produced by conventional in situ burning. This soot production, in fact, is approximately 30 times less than current allowable EPA standards for incinerators and internal combustion engines. Furthermore, as a consequence of the high temperature combustion, the bum rate was established at a very high 3400 gallons per hour for this particular 6 foot diameter structure. The rudimentary design studies we have carried out relative to a seagoing 8 foot diameter incinerator have predicted that a continuous burn rate of 7000 gallons per hour is realistic. This structure was taken as a basis for operational design because it is compatible with C130 flyability, and will be inexpensive enough ($120,000 per copy) to be stored at those seaside depots throughout the US coast line in which the requisite ancillary equipments (booms, service tugs, etc.) are already deployed. The LOX experiments verified our expectations with respect to combustion of debris and various highly weathered or emulsified oils. We have concluded, however, that the use of liquid oxygen in actual beach clean up is not promising because the very high temperatures associated with this combustion are almost certain to produce environmentally deleterious effects on the beach surface and its immediately sublying structures. However, the use of liquid oxygen augmentation for shore based and flyable incinerators may still play an important role in handing the problem of accumulated debris.

  19. Combustion characteristics of biodried sewage sludge.

    Science.gov (United States)

    Hao, Zongdi; Yang, Benqin; Jahng, Deokjin

    2018-02-01

    In this study, effects of biodrying on the characteristics of sewage sludge and the subsequent combustion behavior were investigated. 7-Day of biodrying removed 49.78% of water and 23.17% of VS initially contained in the sewage sludge and increased lower heating value (LHV) by 37.87%. Meanwhile, mass contents of C and N decreased from 36.25% and 6.12% to 32.06% and 4.82%, respectively. Surface of the biodried sewage sludge (BDSS) appeared granulated and multi-porous, which was thought to facilitate air transfer during combustion. According to thermogravimetric (TG) analysis coupled with mass spectrometer (MS) with a heating rate of 10 °C/min from 35 °C to 1000 °C, thermally-dried sewage sludge (TDSS) and BDSS lost 74.39% and 67.04% of the initial mass, respectively. In addition, combustibility index (S) of BDSS (8.67 × 10 -8  min -2  K -3 ) was higher than TDSS. TG-MS analyses also showed that less nitrogenous gases were generated from BDSS than TDSS. It was again showed that the average CO and NO concentrations in exit gas from isothermal combustion of BDSS were lower than those from TDSS, especially at low temperatures (≤800 °C). Based on these results, it was concluded that biodrying of sewage sludge was an energy-efficient water-removal method with less emission of air pollutants when BDSS was combusted. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Optimization of combustion chamber geometry for stoichiometric diesel combustion using a micro genetic algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Wook

    2010-11-15

    This paper describes the optimization of combustion chamber geometry and engine operating conditions for stoichiometric diesel combustion, targeting lower gross indicated specific fuel consumption. The KIVA code, coupled with a micro genetic algorithm population of nine for each generation was used. The optimization variables were composed of ten variables related to the combustion chamber geometry and engine operating conditions. In addition, an auto mesh generator was developed for generating various kinds of combustion chambers, such as open-crater, re-entrant, deep, and shallow types. In addition, the computational models were validated against the experimental results for a stoichiometric process in terms of the combustion pressure history and emissions. Through the preset optimization, a 35% improvement in the gross indicated that specific fuel consumption was achieved. In addition, the optimization results showed that the optimum engine operating conditions employed a premixed charge compression ignition combustion regime with early injection and a narrow spray included angle. Furthermore, a higher boost pressure was used to prevent fuel film formation. (author)

  1. COMBUSTION SIMULATION IN A SPARK IGNITION ENGINE CYLINDER: EFFECTS OF AIR-FUEL RATIO ON THE COMBUSTION DURATION

    Directory of Open Access Journals (Sweden)

    Nureddin Dinler

    2010-01-01

    Full Text Available Combustion is an important subject of internal combustion engine studies. To reduce the air pollution from internal combustion engines and to increase the engine performance, it is required to increase combustion efficiency. In this study, effects of air/fuel ratio were investigated numerically. An axisymmetrical internal combustion engine was modeled in order to simulate in-cylinder engine flow and combustion. Two dimensional transient continuity, momentum, turbulence, energy, and combustion equations were solved. The k-e turbulence model was employed. The fuel mass fraction transport equation was used for modeling of the combustion. For this purpose a computational fluid dynamics code was developed by using the finite volume method with FORTRAN programming code. The moving mesh was utilized to simulate the piston motion. The developed code simulates four strokes of engine continuously. In the case of laminar flow combustion, Arrhenius type combustion equations were employed. In the case of turbulent flow combustion, eddy break-up model was employed. Results were given for rich, stoichiometric, and lean mixtures in contour graphs. Contour graphs showed that lean mixture (l = 1.1 has longer combustion duration.

  2. Biomass Suspension Combustion: Effect of Two-Stage Combustion on NOx Emissions in a Laboratory-Scale Swirl Burner

    DEFF Research Database (Denmark)

    Lin, Weigang; Jensen, Peter Arendt; Jensen, Anker Degn

    2009-01-01

    A systematic study was performed in a suspension fired 20 kW laboratory-scale swirl burner test rig for combustion of biomass and co-combustion of natural gas and biomass. The main focus is put on the effect of two-stage combustion on the NO emission, as well as its effect on the incomplete...

  3. Numerical investigation of spray combustion towards HITAC conditions

    OpenAIRE

    Zhu, Shanglong

    2017-01-01

    The features of High Temperature Air Combustion (HiTAC), i.e. high-efficiency combustion processes creating a uniform temperature distribution with low NOX and CO emissions, lend itself ideally for the combustion of all sorts of "difficult” fuels, ranging from low-calorific gases such as waste-gases, to heavy fuel-oils. However, to date most of the applications of HiTAC are for gaseous fuels and solid fuels, while little has been investigated on liquid fuel spray combustion in such combustion...

  4. Stagnation point reverse flow combustor for a combustion system

    Science.gov (United States)

    Zinn, Ben T. (Inventor); Neumeier, Yedidia (Inventor); Seitzman, Jerry M. (Inventor); Jagoda, Jechiel (Inventor); Hashmonay, Ben-Ami (Inventor)

    2007-01-01

    A combustor assembly includes a combustor vessel having a wall, a proximate end defining an opening and a closed distal end opposite said proximate end. A manifold is carried by the proximate end. The manifold defines a combustion products exit. The combustion products exit being axially aligned with a portion of the closed distal end. A plurality of combustible reactant ports is carried by the manifold for directing combustible reactants into the combustion vessel from the region of the proximate end towards the closed distal end.

  5. Production of nanocrystalline metal powders via combustion reaction synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Frye, John G.; Weil, Kenneth Scott; Lavender, Curt A.; Kim, Jin Yong

    2017-10-31

    Nanocrystalline metal powders comprising tungsten, molybdenum, rhenium and/or niobium can be synthesized using a combustion reaction. Methods for synthesizing the nanocrystalline metal powders are characterized by forming a combustion synthesis solution by dissolving in water an oxidizer, a fuel, and a base-soluble, ammonium precursor of tungsten, molybdenum, rhenium, or niobium in amounts that yield a stoichiometric burn when combusted. The combustion synthesis solution is then heated to a temperature sufficient to substantially remove water and to initiate a self-sustaining combustion reaction. The resulting powder can be subsequently reduced to metal form by heating in a reducing gas environment.

  6. Introduction to Physics and Chemistry of Combustion Explosion, Flame, Detonation

    CERN Document Server

    Liberman, Michael A

    2008-01-01

    Most of the material covered in this book deals with the fundamentals of chemistry and physics of key processes and fundamental mechanisms for various combustion and combustion related phenomena in gaseous combustible mixture. It provides the reader with basic knowledge of burning processes and mechanisms of reaction wave propagation. The combustion of a gas mixture (flame, explosion, detonation) is necessarily accompanied by motion of the gas. The process of combustion is therefore not only a chemical phenomenon but also one of gas dynamics. The material selection focuses on the gas phase and

  7. Coal combustion science. Quarterly progress report, July--September 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. [ed.; Baxter, L.L.; Davis, K.A.; Hurt, R.H.; Yang, N.Y.C.

    1995-09-01

    This document is a quarterly status report of the Coal Combustion Science Project that is being conducted at the Combustion Research Facility, Sandia National Laboratories, Livermore, California. The information reported is for the period July-September 1994. The objective of this work is to support the Office of Fossil Energy in executing research on coal combustion science. This project consists of basic research on coal combustion that supports both the Pittsburgh Energy Technology Center (PETC) Direct Utilization Advanced Research and Technology Development Program, and the International Energy Agency (IEA) Coal Combustion Science Project.

  8. Variable compression ratio device for internal combustion engine

    Science.gov (United States)

    Maloney, Ronald P.; Faletti, James J.

    2004-03-23

    An internal combustion engine, particularly suitable for use in a work machine, is provided with a combustion cylinder, a cylinder head at an end of the combustion cylinder and a primary piston reciprocally disposed within the combustion cylinder. The cylinder head includes a secondary cylinder and a secondary piston reciprocally disposed within the secondary cylinder. An actuator is coupled with the secondary piston for controlling the position of the secondary piston dependent upon the position of the primary piston. A communication port establishes fluid flow communication between the combustion cylinder and the secondary cylinder.

  9. Simulation of liquid propellant rocket engine combustion instabilities

    Science.gov (United States)

    Ventrice, M. B.; Fang, J. C.; Purdy, K. R.

    1979-01-01

    A simulation technique for studying the high frequency combustion instabilities of liquid propellant rocket engines has been developed and used to investigate various aspects of instability phenomena. Of importance was investigation of the significance of the method of coupling the combustion and the gas dynamics of the system. Two coupling processes were studied: linear response of the combustion process to pressure fluctuations, and the nature of the resulting instabilities; and nonlinear response of the combustion process to velocity fluctuations, and the nature of the resulting instabilities. For the combustion model studied, nonlinear (velocity) coupling was found to more closely characterize liquid propellant instabilities.

  10. Modelo matricial para la asignación del costo utilizando activity basing cost

    Directory of Open Access Journals (Sweden)

    Julio César Millán-Solarte

    2014-01-01

    Full Text Available Esta investigación presenta la propuesta para asignación de los costos, utilizando la metodología ABC, bajo el modelo matricial. Esto implica la construcción de matrices, entendidas estas como un arreglo ordenado de m filas por n columnas. El costo total para la realización de una actividad se basará en el número de veces que dicha actividad se realice durante un período específico. A partir de lo anterior, se puede obtener el costo total de la fabricación del producto (o la prestación de un servicio si se suman las actividades necesarias para su elaboración.

  11. Algoritmo para detección de vibraciones anormales en maquinarias utilizando la transformada wavelet

    OpenAIRE

    Osorio Sánchez, Arturo

    2006-01-01

    En esta tesis se presenta un análisis de vibraciones mecánicas utilizando la transformada wavelet, proponiéndose un algoritmo de detección basado en la comparación, correlación y regresión de los coeficientes wavelet o detalles y los de escalamiento o aproximación obtenidos de la señal de vibración. Se define una función de detección, dando por resultado un valor de detección que al compararse con un parámetro límite obtenido empíricamente, clasifica la vibración como nor...

  12. Proposta de um curso semipresencial de robótica educacional utilizando a plataforma Arduino

    Directory of Open Access Journals (Sweden)

    Lygia Matos Aquino

    2017-06-01

    Full Text Available A robótica está cada vez mais presente em nosso cotidiano, nas mais diversas áreas (medicina, indústria, entre outras. Esse fato leva a necessidade de disseminar o conhecimento nessa área, de forma, a incentivar novos estudos a fim de solucionar problemas cotidianos para a melhoria da qualidade de vida das pessoas utilizando a robótica. O público-alvo desse trabalho são professores e alunos do ensino fundamental e médio. A ideia central é utilizar a plataforma Arduino em um curso semipresencial de robótica orientado por um facilitador. Inicialmente, esse curso será ofertado a professores com o objetivo de formar futuros multiplicadores de conhecimentos e posteriormente o curso será ofertado com ajuda dos professores tutores que receberam o treinamento previamente

  13. Projeto e desenvolvimento de um carro robô controlado por smartphone, utilizando a plataforma Amarino

    Directory of Open Access Journals (Sweden)

    Otávio Souza Martins Gomes

    2015-01-01

    Full Text Available Este artigo mostra a construção de um carro robô controlado por dispositivos móveis utilizando o sistema operacional Android e uma placa de prototipagem open source (Arduino. Utilizou-se de motores para sua movimentação e sensores para interação com o ambiente. O envio de comandos foi realizado utilizando a tecnologia Bluetooth e é capaz de movimentar o carro robô em todas as direções de acordo com os comandos do usuário. Sensores instalados no carro coletam informações do ambiente que são enviadas ao dispositivo Android. A construção bem sucedida deste carro robô mostra que é possível implementar novas funcionalidades para esse produto, bem como apoiar outros projetos relacionados a esse tema.Palavras-chave: Arduino. Android. Bluetooth. Carro robô. Robótica. Project and development of a robot car controlled by smartphone, using the platform amarinoABSTRACTThis work shows the build of a robot car controlled by mobile devices employing Android operating system and an open source prototyping board (Arduino. Motors for its movements and sensors for its environment interaction were employed. The commands are transmitted using Bluetooth technology which can move the robot car in all directions according to the user commands. Sensors installed in the car collect the environment information which is sent to the Android device. The success build of this robot car shows that new features can be possible implemented as well as to support other projects related to this research area.Keywords: Arduino. Android. Bluetooth. Robot car. Robotic.

  14. Specifics of phytomass combustion in small experimental device

    Directory of Open Access Journals (Sweden)

    Lenhard Richard

    2015-01-01

    Full Text Available A wood pellet combustion carries out with high efficiency and comfort in modern pellet boilers. These facts help to increase the amount of installed pellet boilers in households. The combustion process quality depends besides the combustion conditions also on the fuel quality. The wood pellets, which don`t contain the bark and branches represent the highest quality. Because of growing pellet demand, an herbal biomass (phytomass, which is usually an agricultural by-product becomes economically attractive for pellet production. Although the phytomass has the net calorific value relatively slightly lower than the wood biomass, it is often significantly worse in view of the combustion process and an emission production. The combustion of phytomass pellets causes various difficulties in small heat sources, mainly due to a sintering of fuel residues. We want to avoid the ash sintering by a lowering of temperature in the combustion chamber below the ash sintering temperature of phytomass via the modification of a burner design. For research of the phytomass combustion process in the small boilers is constructed the experimental combustion device. There will investigate the impact of cooling intensity of the combustion chamber on the combustion process and emissions. Arising specific requirements from the measurement will be the basis for the design of the pellet burner and for the setting of operating parameters to the trouble-free phytomass combustion was guaranteed.

  15. Energy and exergy analysis of chemical looping combustion technology and comparison with pre-combustion and oxy-fuel combustion technologies for CO2 capture

    OpenAIRE

    Mukherjee, Sanjay; Kumar, Prashant; Yang, Aidong; Fennell, Paul

    2015-01-01

    Abstract Carbon dioxide (CO2) emitted from conventional coal-based power plants is a growing concern for the environment. Chemical looping combustion (CLC), pre-combustion and oxy-fuel combustion are promising CO2 capture technologies which allow clean electricity generation from coal in an integrated gasification combined cycle (IGCC) power plant. This work compares the characteristics of the above three capture technologies to those of a conventional IGCC plant without CO2 capture. CLC tech...

  16. Combustion chamber and thermal vapor stream producing apparatus and method

    Science.gov (United States)

    Sperry, John S.; Krajicek, Richard W.; Cradeur, Robert R.

    1978-01-01

    A new and improved method and apparatus for burning a hydrocarbon fuel for producing a high pressure thermal vapor stream comprising steam and combustion gases for injecting into a subterranean formation for the recovery of liquefiable minerals therefrom, wherein a high pressure combustion chamber having multiple refractory lined combustion zones of varying diameters is provided for burning a hydrocarbon fuel and pressurized air in predetermined ratios injected into the chamber for producing hot combustion gases essentially free of oxidizing components and solid carbonaceous particles. The combustion zones are formed by zones of increasing diameters up a final zone of decreasing diameter to provide expansion zones which cause turbulence through controlled thorough mixing of the air and fuel to facilitate complete combustion. The high pressure air and fuel is injected into the first of the multiple zones where ignition occurs with a portion of the air injected at or near the point of ignition to further provide turbulence and more complete combustion.

  17. Fluidized bed combustion and its application to refused fuels. Combustion en leche fluido y su aplicacion a combustibles residuales

    Energy Technology Data Exchange (ETDEWEB)

    Euba, J.

    1994-01-01

    As a consequence of the energetic crisis produced in th 70's it was proposed to find new power supplies and it also was the start of the use of traditional energy, which up to that date had not been profitable. At the same time, the worry about the pollutant emissions to the environment was increasing and finally it was approved a new legislation on atmosphere pollution, which is the Directive of the European community Council of 24th November 1988. Under these circumstances there are very important the new technologies for the supply of residual combustion with low values of pollution, where it is very important the combustion in fluidized bed. (Author)

  18. Método de medición de combustible en una embarcación fluvial Método de medicíon de combustible en una embarcacíon fluvial

    Directory of Open Access Journals (Sweden)

    Mauricio Pardo González

    2006-06-01

    Full Text Available Se expone una forma de mejorar el método de medición de combustible en una embarcación fluvial, específicamente en un remolcador. El marco de referencia sobre el que se basa este artículo, es la estrategia utilizada para establecer la cantidad de combustible presente en los tanques de la embarcación. El método que hasta el momento se viene utilizando, produce un error influenciado por factores de perturbación, como la inclinación y la forma de tanqueo del remolcador. Se buscó desarrollar un método alternativo que redujera el error entre el combustible entregado y el medido en la embarcación. Este nuevo método logró ser independiente de la inclinación sin necesidad de utilizar un inclinómetro o instrumento de medida de ángulos.This paper exposes a way to improve the method of fuel measurement in a river vessel, specifically a tugboat. The framework of this article is the need of a strategy to establish the amount of fuel volume that is contained in the tanks of the tugboat. The method, that have been used so far, produces errors influenced by disturbance factors such as the inclination and the shape of the tanks of the tugboat. It is needed to develop an alternative method that reduces the error between the fuel which is provided by the suppliers and the measured one in the tugboat. This new method tries to be independent of the inclination of the boat with no need of using a clinometer or instrument of angle measurement.

  19. Students' understanding of combustion and its instruction

    Science.gov (United States)

    Tai, Chih-Che

    This study examined a cross-age population of 1,237 students from grades 6 through 12 and also 76 university students. Also, 75 8th grade students in two instructional groups were involved in a session of 16-hour science courses. A questionnaire with six knowledge and twelve cognitive ability questions was used to evaluate students' understanding of combustion. Furthermore, one pre-test and two post-tests were used to evaluate students' learning gains in instruction. Video recordings and curriculum materials were examined in terms of how both types of instruction were implemented. Five patterns were found to describe how students developed their understanding of combustion, including (I) gradual increase, (II) stepwise increase, (III) persistent misunderstanding, (IV) early understanding, and (V) varied understanding . The first two patterns are consistent with results from previous studies. However, the next three non-age-growing patterns suggest that the age maturation is not necessarily a determining factor and other variables such as curricula may be more important. Students at different ages applied their knowledge and problem solving strategies differently. The 6--8th grade students used more intuitive, real-life experiences to solve combustion questions in contrast to the 10th grade and older students, who applied more formal science knowledge to solve combustion questions. It was also found that the older students integrated their mobilized knowledge more accurately than the younger learners when they answered combustion questions in different versions of the questionnaire. Two types of instruction, established and experimental, were shown to be effective in promoting 8th grade students' understanding of combustion in the context of Taiwanese classrooms. In addition, although the two types of instruction had been implemented differently, the findings suggested that neither form of instruction was superior to the other as measured by the students

  20. Characterisation of metal combustion with DUST code

    Energy Technology Data Exchange (ETDEWEB)

    García-Cascales, José R., E-mail: jr.garcia@upct.es [DITF, ETSII, Universidad Politécnica de Cartagena, Dr Fleming s/n, 30202 Murcia (Spain); Velasco, F.J.S. [Centro Universitario de la Defensa de San Javier, MDE-UPCT, C/Coronel Lopez Peña s/n, 30730 Murcia (Spain); Otón-Martínez, Ramón A.; Espín-Tolosa, S. [DITF, ETSII, Universidad Politécnica de Cartagena, Dr Fleming s/n, 30202 Murcia (Spain); Bentaib, Ahmed; Meynet, Nicolas; Bleyer, Alexandre [Institut de Radioprotection et Sûreté Nucléaire, BP 17, 92260 Fontenay-aux-Roses (France)

    2015-10-15

    Highlights: • This paper is part of the work carried out by researchers of the Technical University of Cartagena, Spain and the Institute of Radioprotection and Nuclear Security of France. • We have developed a code for the study of mobilisation and combustion that we have called DUST by using CAST3M, a multipurpose software for studying many different problems of Mechanical Engineering. • In this paper, we present the model implemented in the code to characterise metal combustion which describes the combustion model, the kinetic reaction rates adopted and includes a first comparison between experimental data and calculated ones. • The results are quite promising although suggest that improvement must be made on the kinetic of the reaction taking place. - Abstract: The code DUST is a CFD code developed by the Technical University of Cartagena, Spain and the Institute of Radioprotection and Nuclear Security, France (IRSN) with the objective to assess the dust explosion hazard in the vacuum vessel of ITER. Thus, DUST code permits the analysis of dust spatial distribution, remobilisation and entrainment, explosion, and combustion. Some assumptions such as particle incompressibility and negligible effect of pressure on the solid phase make the model quite appealing from the mathematical point of view, as the systems of equations that characterise the behaviour of the solid and gaseous phases are decoupled. The objective of this work is to present the model implemented in the code to characterise metal combustion. In order to evaluate its ability analysing reactive mixtures of multicomponent gases and multicomponent solids, two combustion problems are studied, namely H{sub 2}/N{sub 2}/O{sub 2}/C and H{sub 2}/N{sub 2}/O{sub 2}/W mixtures. The system of equations considered and finite volume approach are briefly presented. The closure relationships used are commented and special attention is paid to the reaction rate correlations used in the model. The numerical

  1. La resolución de problemas geométricos en Matemática utilizando la computadora

    Directory of Open Access Journals (Sweden)

    Osmany Guzmán-Simón

    2017-11-01

    Full Text Available Se presenta un análisis donde se plantean los fundamentos psicopedagógicos que sustentan el desarrollo de habilidades en la resolución de problemas geométricos en la asignatura Matemática, utilizando la computadora.

  2. Interfaz Gráfica Computacional para Destilación Multicomponente utilizando Métodos Cortos

    National Research Council Canada - National Science Library

    A. Osorio Mirón; Gloria Dominguez Hernández

    2011-01-01

    ... número de platos necesarios en el proceso de destilación multicomponente, así como la composición en el flujo de destilado y fondos de una torre de destilación utilizando métodos cortos. La interfaz...

  3. Combustion characteristics and air pollutant formation during oxy-fuel co-combustion of microalgae and lignite.

    Science.gov (United States)

    Gao, Yuan; Tahmasebi, Arash; Dou, Jinxiao; Yu, Jianglong

    2016-05-01

    Oxy-fuel combustion of solid fuels is seen as one of the key technologies for carbon capture to reduce greenhouse gas emissions. The combustion characteristics of lignite coal, Chlorella vulgaris microalgae, and their blends under O2/N2 and O2/CO2 conditions were studied using a Thermogravimetric Analyzer-Mass Spectroscopy (TG-MS). During co-combustion of blends, three distinct peaks were observed and were attributed to C. vulgaris volatiles combustion, combustion of lignite, and combustion of microalgae char. Activation energy during combustion was calculated using iso-conventional method. Increasing the microalgae content in the blend resulted in an increase in activation energy for the blends combustion. The emissions of S- and N-species during blend fuel combustion were also investigated. The addition of microalgae to lignite during air combustion resulted in lower CO2, CO, and NO2 yields but enhanced NO, COS, and SO2 formation. During oxy-fuel co-combustion, the addition of microalgae to lignite enhanced the formation of gaseous species. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Combustion Safety Simplified Test Protocol Field Study

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L. [Gas Technology Inst., Des Plaines, IL (United States); Cautley, D. [Gas Technology Inst., Des Plaines, IL (United States); Bohac, D. [Gas Technology Inst., Des Plaines, IL (United States); Francisco, P. [Gas Technology Inst., Des Plaines, IL (United States); Shen, L. [Gas Technology Inst., Des Plaines, IL (United States); Gloss, S. [Gas Technology Inst., Des Plaines, IL (United States)

    2015-11-01

    Combustions safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives. A survey of state weatherization agencies on combustion safety issues, details of a field data collection instrumentation package, summary of data collected over seven months, data analysis and results are included. The project team collected field data on 11 houses in 2015.

  5. Clean coal combustion in domestic sector

    Energy Technology Data Exchange (ETDEWEB)

    Dreszer, K.; Kubica, K.; Sciazko, M. [Institute for Chemical Processing of Coal, Zabrze (Poland)

    1998-12-31

    Combustion of raw coal in existing domestic furnaces with a low efficiency (usually below 50%) is a source of pollutants generation like dust, SO{sub 2} and PAH including cancerogenic BAP, resulting in serious environmental problems. Emission of pollutants depends on solid fuels quality and fuel combustion parameters. Pollutants emission can be decreased by the use of upgraded coal derived solid fuels or replacement of old heating appliances with new ones with high thermal efficiency and ecological affectivity. Several ecological fuels manufacturing methods have been elaborated in the Institute for Chemical Processing of Coal. Thermal and emission tests of heating devices and solid fuels were performed with the use of IChPW experimental plant. Results were confirmed in heating devices in real heating objects. Taking results into account proposal of legal regulation for Polish domestic sector was elaborated. 4 figs., 2 tabs.

  6. Clean coal combustion in domestic sector

    Energy Technology Data Exchange (ETDEWEB)

    Dreszer, K.; Kubica, K.; Sciazko, M. (Institute for Chemical Processing of Coal, Zabrze (Poland))

    1998-01-01

    Combustion of raw coal in existing domestic furnaces with a low efficiency (usually below 50%) is a source of pollutants generation like dust, SO[sub 2] and PAH including cancerogenic BAP, resulting in serious environmental problems. Emission of pollutants depends on solid fuels quality and fuel combustion parameters. Pollutants emission can be decreased by the use of upgraded coal derived solid fuels or replacement of old heating appliances with new ones with high thermal efficiency and ecological affectivity. Several ecological fuels manufacturing methods have been elaborated in the Institute for Chemical Processing of Coal. Thermal and emission tests of heating devices and solid fuels were performed with the use of IChPW experimental plant. Results were confirmed in heating devices in real heating objects. Taking results into account proposal of legal regulation for Polish domestic sector was elaborated. 4 figs., 2 tabs.

  7. Future fundamental combustion research for aeropropulsion systems

    Science.gov (United States)

    Mularz, E. J.

    1985-01-01

    Physical fluid mechanics, heat transfer, and chemical kinetic processes which occur in the combustion chamber of aeropropulsion systems were investigated. With the component requirements becoming more severe for future engines, the current design methodology needs the new tools to obtain the optimum configuration in a reasonable design and development cycle. Research efforts in the last few years were encouraging but to achieve these benefits research is required into the fundamental aerothermodynamic processes of combustion. It is recommended that research continues in the areas of flame stabilization, combustor aerodynamics, heat transfer, multiphase flow and atomization, turbulent reacting flows, and chemical kinetics. Associated with each of these engineering sciences is the need for research into computational methods to accurately describe and predict these complex physical processes. Research needs in each of these areas are highlighted.

  8. Secondary combustion system for wood burning stove

    Energy Technology Data Exchange (ETDEWEB)

    von Conta, P.E.W.

    1986-12-16

    This patent describes an improved secondary combustion system for combusting the exhaust gases exiting from a fire box in a wood burning stove comprising: an insulated conduit defining an exhaust passageway leading from an intake opening to an exit opening; screen means interposed across the exhaust passageway in the vicinity of the intake opening to impart a rapid acceleration to a gas stream entering the exhaust passageway; rotation means to impart a rotation to the gas stream in a first portion of the exhaust passageway; counter-rotation means to impart a counter-rotation to the gas stream in a second portion of the exhaust passageway; deceleration means to decelerate the gas stream in the second portion of the exhaust passageway; and secondary air means to inject a source of secondary air into the exhaust passageway.

  9. Synthesis of functional materials in combustion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Zhuravlev, V. D., E-mail: zhvd@ihim.uran.ru; Bamburov, V. G.; Ermakova, L. V.; Lobachevskaya, N. I. [Russian Academy of Sciences, Institute of Solid State Chemistry, Ural Branch (Russian Federation)

    2015-12-15

    The conditions for obtaining oxide compounds in combustion reactions of nitrates of metals with organic chelating–reducing agents such as amino acids, urea, and polyvinyl alcohol are reviewed. Changing the nature of internal fuels and the reducing agent-to-oxidizing agent ratio makes possible to modify the thermal regime of the process, fractal dimensionality, morphology, and dispersion of synthesized functional materials. This method can be used to synthesize simple and complex oxides, composites, and metal powders, as well as ceramics and coatings. The possibilities of synthesis in combustion reactions are illustrated by examples of αand γ-Al{sub 2}O{sub 3}, YSZ composites, uranium oxides, nickel powder, NiO and NiO: YSZ composite, TiO{sub 2}, and manganites, cobaltites, and aluminates of rare earth elements.

  10. Synthesis of functional materials in combustion reactions

    Science.gov (United States)

    Zhuravlev, V. D.; Bamburov, V. G.; Ermakova, L. V.; Lobachevskaya, N. I.

    2015-12-01

    The conditions for obtaining oxide compounds in combustion reactions of nitrates of metals with organic chelating-reducing agents such as amino acids, urea, and polyvinyl alcohol are reviewed. Changing the nature of internal fuels and the reducing agent-to-oxidizing agent ratio makes possible to modify the thermal regime of the process, fractal dimensionality, morphology, and dispersion of synthesized functional materials. This method can be used to synthesize simple and complex oxides, composites, and metal powders, as well as ceramics and coatings. The possibilities of synthesis in combustion reactions are illustrated by examples of αand γ-Al2O3, YSZ composites, uranium oxides, nickel powder, NiO and NiO: YSZ composite, TiO2, and manganites, cobaltites, and aluminates of rare earth elements.

  11. Internal Combustion Engine Principles with Vehicle Applications

    DEFF Research Database (Denmark)

    Sorenson, Spencer C

    The book is an introductory text on the subject of internal combustion engines, intended for use in engineering courses at the senior or introductory graduate student level. The focus in on describing the basic principles of engine operation on a broad basis, to provide a foundation for further...... exchange processes, combustion in different engine types, exhaust emissions, engine control including mean value engine models, pressure charging, fuels and fuel systems, balancing, friction, and heat transfer. In addition, methods to establish the connection between engine characteristics and vehicle...... study, research and development. The goal is to describe the main variables involved in engine operation of different engine types, and how their interaction determines engine performance. Topics included are: general engine parameters, thermodynamic cycles including simple engine simulation, air...

  12. Influence of Coal Quality on Combustion Performance

    DEFF Research Database (Denmark)

    Lans, Robert Pieter Van Der; Glarborg, Peter; Dam-Johansen, Kim

    1998-01-01

    mixing pattern on NO formation under these conditions. Emissions from the opposed fired plant with all combustion air introduced through the burners could only be qualitatively reproduced by the pilot furnace. Under single stage conditions the test rig provided higher NO levels. Carbon in ash levels did...... not show any correlation between the coals and the furnaces. An engineering, mathematical model has been developed describing radiation heat transfer and coal combustion in full scale furnaces. The model has been validated against measured temperatures and the amount of carbon in fly ash. The model...... was well able to predict average temperature and carbon in ash levels, but failed to predict the influence of coal quality on both temperature and carbon in ash. A brief parametric study has been performed on important model parameters....

  13. Factors Influencing Temperature Fields during Combustion Reactions

    Science.gov (United States)

    2014-05-20

    promoting thermal energy distributions. Keywords: Thermites · Nanoparticle combustion • Aluminum · Infrared thermometry • Non-ideal explosives 1...materials (nano- thermite ) comprised of a metallic fuel and organic or metal- lic oxidizer and will be referred to as nanothermites hence forth. The most...magnesium (Mg), manganese (Mn), and titanium (Ti) nanoparticles were added to Al/CuO at 10% by weight of the nanothermite sample. The nano- thermites with

  14. Combustión y combustibles

    Directory of Open Access Journals (Sweden)

    Virella, A.

    1961-06-01

    Full Text Available Not availableLa ponencia trata de los combustibles generalmente empleados en los hornos rotativos de cemento Portland y, especialmente, de los problemas relacionados con los carbones pobres. En cualquier caso, hay que tener un conocimiento previo del poder calorífico del combustible que se pretende emplear, siendo de considerar antes el coste por unidad de calor que el coste por unidad de peso. Se describen el secado y la molienda de los carbones, señalando la tendencia actual de efectuar ambas operaciones simultáneamente, definiendo la aptitud para la pulverización y la determinación de la finura del polvo de carbón, por los métodos clásicos y por medio del permeabilímetro. Se expone en qué medida influyen la finura del combustible, el sistema de inyección, el estado del aire primario, su poder comburente, el exceso de aire y la proporción de cenizas en la determinación de la temperatura de la llama, su poder radiante, el flujo térmico y la posibilidad de obtener un clínker bien cocido. Se propugna por el empleo conjunto de aceites combustibles y carbones pobres como solución muy apropiada en la mayoría de los casos. Por último, se menciona la posibilidad de que se formen anillos en los hornos rotativos como consecuencia del empleo de carbones de alto contenido de cenizas, indicando algunas soluciones para evitar dicha perturbación.

  15. Combustion in microgravity: The French contribution

    Science.gov (United States)

    Prud'homme, Roger; Legros, Guillaume; Torero, José L.

    2017-01-01

    Microgravity (drop towers, parabolic flights, sounding rockets and space stations) are particularly relevant to combustion problems given that they show high-density gradients and in many cases weak forced convection. For some configurations where buoyancy forces result in complex flow fields, microgravity leads to ideal conditions that correspond closely to canonical problems, e.g., combustion of a spherical droplet in a far-field still atmosphere, Emmons' problem for flame spreading over a solid flat plate, deflagration waves, etc. A comprehensive chronological review on the many combustion studies in microgravity was written first by Law and Faeth (1994) and then by F.A. Williams (1995). Later on, new recommendations for research directions have been delivered. In France, research has been managed and supported by CNES and CNRS since the creation of the microgravity research group in 1992. At this time, microgravity research and future activities contemplated the following: Droplets: the "D2 law" has been well verified and high-pressure behavior of droplet combustion has been assessed. The studies must be extended in two main directions: vaporization in mixtures near the critical line and collective effects in dense sprays. Flame spread: experiments observed blue flames governed by diffusion that are in accordance with Emmons' theory. Convection-dominated flames showed significant departures from the theory. Some theoretical assumptions appeared controversial and it was noted that radiation effects must be considered, especially when regarding the role of soot production in quenching. Heterogeneous flames: two studies are in progress, one in Poitiers and the other in Marseilles, about flame/suspension interactions. Premixed and triple flames: the knowledge still needs to be complemented. Triple flames must continue to be studied and understanding of "flame balls" still needs to be addressed.

  16. Chemical Kinetic Models for Advanced Engine Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Pitz, William J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mehl, Marco [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Westbrook, Charles K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-10-22

    The objectives for this project are as follows: Develop detailed chemical kinetic models for fuel components used in surrogate fuels for compression ignition (CI), homogeneous charge compression ignition (HCCI) and reactivity-controlled compression-ignition (RCCI) engines; and Combine component models into surrogate fuel models to represent real transportation fuels. Use them to model low-temperature combustion strategies in HCCI, RCCI, and CI engines that lead to low emissions and high efficiency.

  17. Combustion modeling in advanced gas turbine systems

    Energy Technology Data Exchange (ETDEWEB)

    Smoot, L.D.; Hedman, P.O.; Fletcher, T.H. [Brigham Young Univ., Provo, UT (United States)] [and others

    1995-10-01

    The goal of the U.S. Department of Energy`s Advanced Turbine Systems (ATS) program is to help develop and commercialize ultra-high efficiency, environmentally superior, and cost competitive gas turbine systems for base-load applications in the utility, independent power producer, and industrial markets. Combustion modeling, including emission characteristics, has been identified as a needed, high-priority technology by key professionals in the gas turbine industry.

  18. Gasohol : un combustible limpio para Colombia

    OpenAIRE

    Ocampo González, Aquiles

    1998-01-01

    Se describe un estudio sobre las posibilidades reales que tiene Colombia de establecer un programa masivo para utilizar mezclas de etanol y gasolina como combustible automotor, teniendo en cuenta que la materia prima más probable deberá ser la caña de azúcar. Se discuten los efectos ambientales, socioeconómicos y técnicos de dicho programa.

  19. Kinetics and Product Channels in Combustion Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Hershberger, John F. [North Dakota State Univ., Fargo, ND (United States)

    2017-02-28

    We report study of the chemical kinetics and/or photochemistry of several chemical reactions of potential interest in understanding the gas phase combustion chemistry of nitrogen-containing molecules. Studies completed during the final grant period include determination of quantum yields of the photolysis of HCNO, fulminic acid, a kinetics and product channel study of the reaction of CN radicals with methyl bromide, and study of the products of the reaction of hydroxymethyl radical with nitric oxide.

  20. Industrial combustion monitoring using optical sensors

    Science.gov (United States)

    Von Drasek, William A.; Charon, Olivier; Marsais, Olivier

    1999-01-01

    With stricter environmental regulations optimization of the combustion process for reduced pollutant emission and higher fuel efficiency is a major objective for manufacturers. The promotion of oxy-fuel combustion is one alternative technology that has been demonstrated as a means for manufacturers to meet their environmental objectives. Despite the benefits oxy-fuel combustion can offer further optimization using monitoring and control techniques are still needed. Here we present a novel method for monitoring and controlling oxy-fuel burners by strategic placement of optical sensors. The sensors are integrated into an industrial oxy-fuel capable of withstanding harsh environments. Radiation from the flame at selected wavelength regions is collected by fiber optics attached to the burner and transported to a miniaturized PC-based spectrometer. The spectral information obtained is used to construct a neural network (NN) model that relates the real- time signal collected to burner operating parameters such as, stoichiometry, power, and fueled and/or oxidizer changes. This processed information from the NN can then be used in a control-loop for adjusting and optimizing combustion parameters or alerting operators of potential burner problems. Examples of using this technology on AIr Liquide's pilot furnaces in both the US and France and from an industrial glass melting tank will be presented. The potential of the sensor and NN approach is demonstrated for both conventional burner and an advanced wide flame burner. The results show that both stoichiometry and power changes can reliably be detected by use of the optical sensors. In addition, an example demonstrating the method on oxy-fuel oil flames to monitor oil atomization quality and stoichiometry will be presented.

  1. Combustion Waves and Fronts in Flows

    Science.gov (United States)

    Clavin, Paul; Searby, Geoff

    2016-07-01

    Preface; Introduction; Part I. Physical Insights: 1. General considerations; 2. Laminar premixed flames; 3. Turbulent premixed flames; 4. Gaseous shocks and detonations; 5. Chemical kinetics of combustion; 6. Laser-driven ablation front in ICF; 7. Explosion of massive stars; Part II. Detailed Analytical Studies: 8. Planar flames; 9. Flame kernels and flame balls; 10. Wrinkled flames; 11. Ablative Rayleigh-Taylor instability; 12. Shock waves and detonations; Part III. Complements: 13. Statistical physics; 14. Chemistry; 15. Flows; References; Index.

  2. Combustion, pyrolysis, gasification, and liquefaction of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Reed, T.B.

    1980-09-01

    All the products now obtained from oil can be provided by thermal conversion of the solid fuels biomass and coal. As a feedstock, biomass has many advantages over coal and has the potential to supply up to 20% of US energy by the year 2000 and significant amounts of energy for other countries. However, it is imperative that in producing biomass for energy we practice careful land use. Combustion is the simplest method of producing heat from biomass, using either the traditional fixed-bed combustion on a grate or the fluidized-bed and suspended combustion techniques now being developed. Pyrolysis of biomass is a particularly attractive process if all three products - gas, wood tars, and charcoal - can be used. Gasification of biomass with air is perhaps the most flexible and best-developed process for conversion of biomass to fuel today, yielding a low energy gas that can be burned in existing gas/oil boilers or in engines. Oxygen gasification yields a gas with higher energy content that can be used in pipelines or to fire turbines. In addition, this gas can be used for producing methanol, ammonia, or gasoline by indirect liquefaction. Fast pyrolysis of biomass produces a gas rich in ethylene that can be used to make alcohols or gasoline. Finally, treatment of biomass with high pressure hydrogen can yield liquid fuels through direct liquefaction.

  3. Oxy-Fuel Combustion of Coal

    DEFF Research Database (Denmark)

    Brix, Jacob

    . % it was found that char conversion rate was lowered in O2/CO2 compared to O2/N2. This is caused by the lower diffusion coefficient of O2 in CO2 (~ 22 %) that limits the reaction rate in zone III compared to combustion in O2/N2. Using char sampled in the EFR experiments ThermoGravimetric Analyzer (TGA......) reactivity profiles for combustion and CO2 gasification has been found at 5 vol. % O2 or 80 vol. % CO2 and a heating rate of 5 K/min to a peak temperature of 1273 K or 1373 K. These experiments did not reveal differences in reactivity between EFR-chars formed in O2/N2 and O2/CO2. Reactivity profiles for TGA...... upon particle ignition at the high O2 concentrations. From TGA reactivity profiles of EFR-chars devolatilized at 1173 K – 1673 K intrinsic kinetic parameters has been found for combustion. The rate constant includes both a deactivation and an activation term. Intrinsic kinetics was also found for CO2...

  4. Wood combustion systems: status of environmental concerns

    Energy Technology Data Exchange (ETDEWEB)

    Dunwoody, J.E.; Takach, H.; Kelley, C.S.; Opalanko, R.; High, C.; Fege, A.

    1980-01-01

    This document addresses the uncertainties about environmental aspects of Wood Combustion Systems that remain to be resolved through research and development. The resolution of these uncertainties may require adjustments in the technology program before it can be commercialized. The impacts and concerns presented in the document are treated generically without reference to specific predetermined sites unless these are known. Hence, site-specific implications are not generally included in the assessment. The report consists of two main sections which describe the energy resource base involved, characteristics of the technology, and introduce the environmental concerns of implementing the technology; and which review the concerns related to wood combustion systems which are of significance for the environment. It also examines the likelihood and consequence of findings which might impede wood commercialization such as problems and uncertainties stemming from current or anticipated environmental regulation, or costs of potential environmental controls. This document is not a formal NEPA document. Appropriate NEPA documentation will be prepared after a formal wood combustion commercialization program is approved by DOE.

  5. Reduced chemical kinetics for propane combustion

    Science.gov (United States)

    Ying, Shuh-Jing; Nguyen, Hung Lee

    1990-01-01

    It is pointed out that a detailed chemical kinetics mechanism for the combustion of propane consists of 40 chemical species and 118 elementary chemical reactions. An attempt is made to reduce the number of chemical species and elementary chemical reactions so that the computer run times and storage requirements may be greatly reduced in three-dimensional gas turbine combustion flow calculations, while maintaining accurate predictions of the propane combustion and exhaust emissions. By way of a sensitivity analysis, the species of interest and chemical reactions are classified in descending order of importance. Nineteen species are chosen, and their pressure, temperature, and concentration profiles are presented for the reduced mechanisms, which are then compared with those from the full 118 reactions. It is found that 45 reactions involving 27 species have to be kept for comparable agreement. A comparison of the results obtained from the 45 reactions to that of the full 118 shows that the pressure and temperature profiles and concentrations of C3H8, O2, N2, H2O, CO, and CO2 are within 10 percent of maximum change.

  6. Pilot project: Wood chip combustion plant

    Energy Technology Data Exchange (ETDEWEB)

    Malsburg, G. von.

    1984-01-01

    Wood chip combustion systems as an alternative heating system can be operated at a justifiable expense of money and work. With the present cost structure such a system becomes interesting at an annual heating oil consumption of 10.000 l or more. The economic efficiency depends on the one hand on the level of the fixed costs and on the price of m/sup 3/ of wood chips on the other. Satisfactory automatic operation of a wood-chip combustion system is possible. The fuel, however, must be more or less homogeneous. The system uses feeder screws and due to the little space it needs it can be fitted to almost any existing heating system. If the heat demand and the chip feed are matched well and if the exchanger surfaces are cleaned regularly the waste gas temperatures will be low. Overheating does not occur and pollution is expected to be lower than in piece-wood fueled systems because the combustion process actually alternates between full operation mode and standstill. In standstill mode only a small fire is being maintained so that the production of nitric oxides, gases and emissions (tar, soot, dust etc.) is expected to drop sharply. Measurements of all these substances will be carried out during the heating period 1983/84.

  7. Real-Time Combustion Controls and Diagnostics Sensors (CCADS)

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, J.D.; Richard, G.A.; Dodrill, K.A.; Nutter, R.S. Jr; Straub, D.

    2005-05-03

    The present invention is directed to an apparatus for the monitoring of the combustion process within a combustion system. The apparatus comprises; a combustion system, a means for supplying fuel and an oxidizer, a device for igniting the fuel and oxidizer in order to initiate combustion, and a sensor for determining the current conducted by the combustion process. The combustion system comprises a fuel nozzle and an outer shell attached to the combustion nozzle. The outer shell defines a combustion chamber. Preferably the nozzle is a lean premix fuel nozzle (LPN). Fuel and an oxidizer are provided to the fuel nozzle at separate rates. The fuel and oxidizer are ignited. A sensor positioned within the combustion system comprising at least two electrodes in spaced-apart relationship from one another. At least a portion of the combustion process or flame is between the first and second electrodes. A voltage is applied between the first and second electrodes and the magnitude of resulting current between the first and second electrodes is determined.

  8. Hybrid Combustion-Gasification Chemical Looping

    Energy Technology Data Exchange (ETDEWEB)

    Herbert Andrus; Gregory Burns; John Chiu; Gregory Lijedahl; Peter Stromberg; Paul Thibeault

    2009-01-07

    For the past several years Alstom Power Inc. (Alstom), a leading world-wide power system manufacturer and supplier, has been in the initial stages of developing an entirely new, ultra-clean, low cost, high efficiency power plant for the global power market. This new power plant concept is based on a hybrid combustion-gasification process utilizing high temperature chemical and thermal looping technology The process consists of the oxidation, reduction, carbonation, and calcination of calcium-based compounds, which chemically react with coal, biomass, or opportunity fuels in two chemical loops and one thermal loop. The chemical and thermal looping technology can be alternatively configured as (i) a combustion-based steam power plant with CO{sub 2} capture, (ii) a hybrid combustion-gasification process producing a syngas for gas turbines or fuel cells, or (iii) an integrated hybrid combustion-gasification process producing hydrogen for gas turbines, fuel cells or other hydrogen based applications while also producing a separate stream of CO{sub 2} for use or sequestration. In its most advanced configuration, this new concept offers the promise to become the technology link from today's Rankine cycle steam power plants to tomorrow's advanced energy plants. The objective of this work is to develop and verify the high temperature chemical and thermal looping process concept at a small-scale pilot facility in order to enable AL to design, construct and demonstrate a pre-commercial, prototype version of this advanced system. In support of this objective, Alstom and DOE started a multi-year program, under this contract. Before the contract started, in a preliminary phase (Phase 0) Alstom funded and built the required small-scale pilot facility (Process Development Unit, PDU) at its Power Plant Laboratories in Windsor, Connecticut. Construction was completed in calendar year 2003. The objective for Phase I was to develop the indirect combustion loop with CO{sub 2

  9. Control issues in oxy-fuel combustion

    Energy Technology Data Exchange (ETDEWEB)

    Snarheim, Dagfinn

    2009-08-15

    Combustion of fossil fuels is the major energy source in todays society. While the use of fossil fuels is a necessity for our society to function, there has been an increasing concern on the emissions of CO{sub 2} resulting from human activities. Emissions of CO{sub 2} are considered to be the main cause for the global warming and climate changes we have experienced in recent years. To fight the climate changes, the emissions of CO{sub 2} must be reduced in a timely fashion. Strategies to achieve this include switching to less carbon intensive fuels, renewable energy sources, nuclear energy and combustion with CO{sub 2} capture. The use of oxy-fuel combustion is among the alternative post- and pre combustion capture concepts, a strategy to achieve power production from fossil fuels with CO{sub 2} capture. In an oxy-fuel process, the fuel is burned in a mixture of oxygen and CO{sub 2} (or steam), leaving the exhaust consisting mainly of CO{sub 2} and steam. The steam can be removed by use of a condenser, leaving (almost) pure CO{sub 2} ready to be captured. The downside to CO{sub 2} capture is that it is expensive, both in capital cost of extra equipment, and in operation as it costs energy to capture the CO{sub 2}. Thus it is important to maximize the efficiency in such plants. One attractive concept to achieve CO{sub 2} capture by use of oxy-fuel, is a semi-closed oxy-fuel gas turbine cycle. The dynamics of such a plant are highly integrated, involving energy and mass recycle, and optimizing efficiency might lead to operational (control) challenges. In these thesis we investigate how such a power cycle should be controlled. By looking at control at such an early stage in the design phase, it is possible to find control solutions otherwise not feasible, that leads to better overall performance. Optimization is used on a nonlinear model based on first principles, to compare different control structures. Then, closed loop simulations using MPC, are used to validate

  10. Quantitative Measurement of Oxygen in Microgravity Combustion

    Science.gov (United States)

    Silver, Joel A.

    1997-01-01

    A low-gravity environment, in space or in ground-based facilities such as drop towers, provides a unique setting for studying combustion mechanisms. Understanding the physical phenomena controlling the ignition and spread of flames in microgravity has importance for space safety as well as for better characterization of dynamical and chemical combustion processes which are normally masked by buoyancy and other gravity-related effects. Due to restrictions associated with performing measurements in reduced gravity, diagnostic methods which have been applied to microgravity combustion studies have generally been limited to capture of flame emissions on film or video, laser Schlieren imaging and (intrusive) temperature measurements using thermocouples. Given the development of detailed theoretical models, more sophisticated diagnostic methods are needed to provide the kind of quantitative data necessary to characterize the properties of microgravity combustion processes as well as provide accurate feedback to improve the predictive capabilities of the models. When the demands of space flight are considered, the need for improved diagnostic systems which are rugged, compact, reliable, and operate at low power becomes apparent. The objective of this research is twofold. First, we want to develop a better understanding of the relative roles of diffusion and reaction of oxygen in microgravity combustion. As the primary oxidizer species, oxygen plays a major role in controlling the observed properties of flames, including flame front speed (in solid or liquid flames), extinguishment characteristics, flame size and flame temperature. The second objective is to develop better diagnostics based on diode laser absorption which can be of real value in both microgravity combustion research and as a sensor on-board Spacelab as either an air quality monitor or as part of a fire detection system. In our prior microgravity work, an eight line-of-sight fiber optic system measured

  11. ANALYSIS OF INTERNAL COMBUSTION ENGINE WITH A NEW CONCEPT OF POROUS MEDIUM COMBUSTION FOR THE FUTURE CLEAN ENGINE

    Directory of Open Access Journals (Sweden)

    Ashok A Dhale

    2010-01-01

    Full Text Available At present, the emissions of internal combustion engine can only be improved by catalytic treatments of the exhaust gases. Such treatments, however, result in high costs and relatively low conversion efficiency. This suggests that a new combustion technique should be developed to yield improved primary combustion processes inside the engine with drastically reduced exhaust gas emissions. To fulfill all requirements, Dr. Franz Drust has proposed a new combustion concept to perform homogenous combustion in internal combustion engines. This concept used the porous medium combustion technique and is called "PM-engine". It is shown that the PM combustion technique can be applied to internal combustion engines. Theoretical considerations are presented for internal combustion engines, indicating that an overall improvement in thermal efficiency can be achieved for the PM-engine. This is explained and general performance of the new PM-engines is demonstrated for a single cylinder, water cooled, direct injection diesel engine. Verification of experiments at primary stage is described that were carried out as a part of the present study.

  12. Novel approaches in advanced combustion characterization of fuels for advanced pressurized combustion

    Energy Technology Data Exchange (ETDEWEB)

    Aho, M.; Haemaelaeinen, J. [VTT Energy (Finland); Joutsenoja, T. [Tampere Univ. of Technology (Finland)

    1996-12-01

    This project is a part of the EU Joule 2 (extension) programme. The objective of the research of Technical Research Centre of Finland (VTT) is to produce experimental results of the effects of pressure and other important parameters on the combustion of pulverized coals and their char derivates. The results can be utilized in modelling of pressurized combustion and in planning pilot-scale reactors. The coals to be studied are Polish hvb coal, French lignite (Gardanne), German anthracite (Niederberg) and German (Goettelbom) hvb coal. The samples are combusted in an electrically heated, pressurized entrained flow reactor (PEFR), where the experimental conditions are controlled with a high precision. The particle size of the fuel can vary between 100 and 300 {mu}m. The studied things are combustion rates, temperatures and sizes of burning single coal and char particles. The latter measurements are performed with a method developed by Tampere University of Technology, Finland. In some of the experiments, mass loss and elemental composition of the char residue are studied in more details as the function of time to find out the combustion mechanism. Combustion rate of pulverized (140-180 {mu}m) Gardanne lignite and Niederberg anthracite were measured and compared with the data obtained earlier with Polish hvb coal at various pressures, gas temperatures, oxygen partial pressures and partial pressures of carbon dioxide in the second working period. In addition, particle temperatures were measured with anthracite. The experimental results were treated with multivariable partial least squares (PLS) method to find regression equation between the measured things and the experimental variables. (author)

  13. PRELIMINARY STUDY ON COMBUSTION AND OVERALL PARAMETERS OF SYNGAS FUEL MIXTURES FOR SPARK IGNITION COMBUSTION ENGINE

    Directory of Open Access Journals (Sweden)

    Rastislav Toman

    2017-02-01

    Full Text Available This paper presents a numerical study on a group of alternative gaseous fuels – syngases, and their use in the spark-ignition internal combustion engine Lombardini LGW 702. These syngas fuel mixtures consist mainly of hydrogen and carbon monoxide, together with inert gases. An understanding of the impact of the syngas composition on the nature of the combustion process is essential for the improvement of the thermal efficiency of syngas-fuelled engines. The paper focuses on six different syngas mixtures with natural gas as a reference. The introduction of the paper goes through some recent trends in the field of the alternative gaseous fuels, followed by a discussion of the objectives of our work, together with the selection of mixtures. Important part of the paper is dedicated to the experimental and above all to the numerical methods. Two different simulation models are showcased: the single-cylinder ‘closed-volume’ combustion analysis model and the full-scale LGW 702 model; all prepared and tuned with the GT-Power software. Steady-state engine measurements are followed by the combustion analysis, which is undertaken to obtain the burn rate profiles. The burn rate profiles, in the form of the Vibe formula, are than inserted into the in-house developed empirical combustion model based on Csallner-Woschni recalculation formulas. Its development is described in the scope as well. The full-scale LGW 702 simulation model, together with this empirical combustion model, is used for the evaluation of engine overall performance parameters, running on gaseous fuel mixtures. The analysis was carried out only under the conditions of engine on full load and the stoichiometric mixture.

  14. Techniques for Liquid Rocket Combustion Spontaneous Stability and Rough Combustion Assessments

    Science.gov (United States)

    Kenny, R. J.; Giacomoni, C.; Casiano, M. J.; Fischbach, S. R.

    2016-01-01

    This work presents techniques for liquid rocket engine combustion stability assessments with respect to spontaneous stability and rough combustion. Techniques covering empirical parameter extraction, which were established in prior works, are applied for three additional programs: the F-1 Gas Generator (F1GG) component test program, the RS-84 preburner component test program, and the Marshall Integrated Test Rig (MITR) program. Stability assessment parameters from these programs are compared against prior established spontaneous stability metrics and updates are identified. Also, a procedure for comparing measured with predicted mode shapes is presented, based on an extension of the Modal Assurance Criterion (MAC).

  15. Disturbing effect of free hydrogen on fuel combustion in internal combustion engines

    Science.gov (United States)

    Riedler, A

    1923-01-01

    Experiments with fuel mixtures of varying composition, have recently been conducted by the Motor Vehicle and Airplane Engine Testing Laboratories of the Royal Technical High School in Berlin and at Fort Hahneberg, as well as at numerous private engine works. The behavior of hydrogen during combustion in engines and its harmful effect under certain conditions, on the combustion in the engine cylinder are of general interest. Some of the results of these experiments are given here, in order to elucidate the main facts and explain much that is already a matter of experience with chauffeurs and pilots.

  16. Temperature Estimation in the Combustion Chamber of an Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Gholam Reza Safakish

    2012-01-01

    Full Text Available The mathematical model of heat transfer phenomena is considered at the combustion chamber wall in an internal combustion (IC engine. The mathematical model of proposed phenomena is established with respect to the crank angle. An inverse heat conduction problem is derived at the cylinder wall, and this problem is investigated numerically using Alifanov's regularization method. This problem studied as an optimization problem in which a squared residual functional is minimized with the conjugate gradient method. To show the ability of the proposed method, some test problems are considered.

  17. Numerical models for the phenomenological study of flameless combustion

    Directory of Open Access Journals (Sweden)

    Bernardo Argemiro Herrera Múnera

    2010-07-01

    Full Text Available Flameless combustion is a technique which offers environmental advantages such as lower than 100 ppm NOx and CO emis- sions due to below 200 K temperature gradients. Flameless combustion also supplies higher than 70% energy efficiency. Knowledge of the phenomena in this combustion regime has been facilitated by using numerical simulation. This paper reviewed the specialised literature about the most commonly used turbulence, combustion, heat transfer and NOx formation models in modelling flameless combustion with CFD codes. The review concluded that the k-ε standard model is the most used for turbu- lence. Finite rate/eddy dissipation with modified constants and eddy dissipation concept models are suitable for combustion reac- tions, discrete ordinates and weighted sum gray gas (WSGG models are used for radiation and thermal, prompt and N2O inter- mediate models are used for NOx.

  18. Construction of a power plant with prototype DLN combustion turbines

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, M.L. [CSW Energy, Dallas, TX (United States); Drummond, L.J. [Zurn NEPCO, Redmond, WA (United States)

    1996-12-31

    Design and construction of a power plant is always a difficult process and this is especially true when the main keystone, the combustion turbine engine, is being modified by the manufacturer resulting in numerous changes in the design interfaces. The development of the design and construction of the Orange Cogeneration Facility has been in parallel with major modification of the LM6000 to DLE technology (a Dry Low NO{sub x} combustion system). The Dry Low NO{sub x} Combustion System for a combustion turbine offered a means to reduce water usage, lower Zero Liquid Discharge System operating costs and reduce emissions to meet Florida Department of Environmental Protection requirements. This development was successfully accomplished by Owner, EPC contractor and Combustion Turbine Manufacturer by maintaining flexibility in the design and construction while the design interfaces and performance of the combustion turbines were being finalized.

  19. JANNAF 35th Combustion Subcommittee Meeting. Volume 1

    Science.gov (United States)

    Fry, Ronald S. (Editor); Gannaway, Mary T. (Editor); Rognan, Melanie (Editor)

    1998-01-01

    Volume 1, the first of two volumes is a compilation of 63 unclassified/unlimited distribution technical papers presented at the 35th meeting of the Joint Army-Navy-NASA-Air Force (JANNAF) Combustion Subcommittee (CS) held jointly with the 17th Propulsion Systems Hazards Subcommittee (PSHS) and Airbreathing Propulsion Subcommittee (APS). The meeting was held on 7-11 December 1998 at Raytheon Systems Company and the Marriott Hotel, Tucson, AZ. Topics covered include solid gun propellant processing, ignition and combustion, charge concepts, barrel erosion and flash, gun interior ballistics, kinetics and molecular modeling, ETC gun modeling, simulation and diagnostics, and liquid gun propellant combustion; solid rocket motor propellant combustion, combustion instability fundamentals, motor instability, and measurement techniques; and liquid and hybrid rocket combustion.

  20. Internet of Things Based Combustible Ice Safety Monitoring System Framework

    Science.gov (United States)

    Sun, Enji

    2017-05-01

    As the development of human society, more energy is requires to meet the need of human daily lives. New energies play a significant role in solving the problems of serious environmental pollution and resources exhaustion in the present world. Combustible ice is essentially frozen natural gas, which can literally be lit on fire bringing a whole new meaning to fire and ice with less pollutant. This paper analysed the advantages and risks on the uses of combustible ice. By compare to other kinds of alternative energies, the advantages of the uses of combustible ice were concluded. The combustible ice basic physical characters and safety risks were analysed. The developments troubles and key utilizations of combustible ice were predicted in the end. A real-time safety monitoring system framework based on the internet of things (IOT) was built to be applied in the future mining, which provide a brand new way to monitoring the combustible ice mining safety.

  1. Flow and Combustion in Advanced Gas Turbine Combustors

    CERN Document Server

    Janicka, Johannes; Schäfer, Michael; Heeger, Christof

    2013-01-01

    With regard to both the environmental sustainability and operating efficiency demands, modern combustion research has to face two main objectives, the optimization of combustion efficiency and the reduction of pollutants. This book reports on the combustion research activities carried out within the Collaborative Research Center (SFB) 568 “Flow and Combustion in Future Gas Turbine Combustion Chambers” funded by the German Research Foundation (DFG). This aimed at designing a completely integrated modeling and numerical simulation of the occurring very complex, coupled and interacting physico-chemical processes, such as turbulent heat and mass transport, single or multi-phase flows phenomena, chemical reactions/combustion and radiation, able to support the development of advanced gas turbine chamber concepts.

  2. Dust Cloud Combustion for Defeat of Airborne Bio-WMD

    Science.gov (United States)

    2017-12-01

    gases [4], paint pigments and solvents [5], plastic powders and solvents [6] or even metal particles with hydrogen, natural gas or other vapors in... Nanoparticle Streams in Post Flame Environment. Proc. Combust. Inst. 2014, DOI: 10.1016/j.proci.2014.06.127. [5] G. Young, K. Sullivan, M.R. Zachariah...and K. Yu, Combustion Characteristics of Boron Nanoparticles . Combust. Flame 2009, 156, 322-333. [6] M. Soo, P. Julien, S. Goroshin, J.M. Bergthorson

  3. Numerical Analysis on Combustion Characteristic of Leaf Spring Rotary Engine

    OpenAIRE

    Yan Zhang; Zhengxing Zuo; Jinxiang Liu

    2015-01-01

    The purpose of this paper is to investigate combustion characteristics for rotary engine via numerical studies. A 3D numerical model was developed to study the influence of several operative parameters on combustion characteristics. A novel rotary engine called, “Leaf Spring Rotary Engine”, was used to illustrate the structure and principle of the engine. The aims are to (1) improve the understanding of combustion process, and (2) quantify the influence of rotational speed, excess air ratio, ...

  4. Numerical Simulation Method for Combustion in a Oxyhydrogen Rocket Motor

    OpenAIRE

    Taki, Shiro; Fujiwara, Toshitaka; 滝, 史郎; 藤原, 俊隆

    1984-01-01

    Numerical simulations of unsteady phenomena in the combustion chamber of an oxyhydrogen rocket motor were made in an attempt to develop a computer code for use in investigating such phenomena as vibrating combustion. The combustion in this system is controlled by diffusion, the effect of which works much slower than sound or pressure waves, so that diffusions are usually solved using the implicit finite difference method for unlimited time step size caused by stability criterion. However, the...

  5. On gas and particle radiation in pulverized fuel combustion furnaces

    DEFF Research Database (Denmark)

    Yin, Chungen

    2015-01-01

    . Although the refined gaseous radiative property model shows great advantages in gaseous fuel combustion modelling, its impacts are largely compromised in pulverized solid fuel combustion, in which particle-radiation interaction plays the dominant role in radiation heat transfer due to high particle loading...... may be compromised by particle radiation in some cases. The gas and particle radiation modelling method and the conclusions presented in this paper are also applied to oxy-fuel combustion of pulverized fuels....

  6. Combustion Synthesis Technology Applied to In-situ Resource Utilization

    Science.gov (United States)

    2006-06-15

    only a solid reaction method but also a hydrothermal , plasma spray decomposition, sol-gel and combustion synthesis techniques. The long-duration...Functional materials, e.g. BaTiO3 , YBa2Cu3O7. Compared with conventional processes, main advantages of combustion synthesis are; The generation...REF: AOARD-05-4043 FINAL TECHNICAL REPORT Combustion Synthesis Technology Applied to In-situ Resource Utilization

  7. Homogeneous Charge Compression Ignition Combustion of Dimethyl Ether

    OpenAIRE

    Pedersen, Troels Dyhr; Schramm, Jesper

    2011-01-01

    This thesis is based on experimental and numerical studies on the use of dimethyl ether (DME) in the homogeneous charge compression ignition (HCCI) combustion process. The first paper in this thesis was published in 2007 and describes HCCI combustion of pure DME in a small diesel engine. The tests were designed to investigate the effect of engine speed, compression ratio and equivalence ratio on the combustion timing and the engine performance. It was found that the required compression ratio...

  8. Analysis of the chemical equilibrium of combustion at constant volume

    OpenAIRE

    Marius BREBENEL

    2014-01-01

    Determining the composition of a mixture of combustion gases at a given temperature is based on chemical equilibrium, when the equilibrium constants are calculated on the assumption of constant pressure and temperature. In this paper, an analysis of changes occurring when combustion takes place at constant volume is presented, deriving a specific formula of the equilibrium constant. The simple reaction of carbon combustion in pure oxygen in both cases (constant pressure and constant ...

  9. Preparação e caracterização de bioanodos para biocélula a combustível etanol/O2

    OpenAIRE

    Sidney Aquino Neto

    2012-01-01

    Este trabalho descreve a preparação e caracterização de bioanodos para biocélula a combustível etanol/O2 utilizando enzimas desidrogenases, tanto com transferência eletrônica mediada como com transferência eletrônica direta. Na primeira etapa do trabalho, os resultados de cinética enzimática com as enzimas comerciais álcool desidrogenase e aldeído desidrogenase em solução e imobilizada mostraram claramente que os vários parâmetros cinéticos analisados devem ser considerados, a fim de se obter...

  10. Combustion chemistry. Activities in the CHEC research programme

    Energy Technology Data Exchange (ETDEWEB)

    Dam-Johansen, K.; Johnsson, J.E.; Glarborg, P.; Frandsen, F.; Jensen, A.; Oestberg, M. [Technical Univ. of Denmark, Dept. of Chemical Engineering, Lyngby (Denmark)

    1996-12-01

    The combustion chemistry in the oxidation of fossil fuels and biofuels determines together with mixing and heat transfer the required size of a furnace, the emission of gaseous pollutants, and the formation of ash and deposits on surfaces. This paper describes technologies for solid fuels combustion and gives a summary of the fuels, the pollutant chemistry and the inorganic chemistry in combustion processes. Emphasis is put on the work carried out in the CHEC (Combustion and Harmful Emission Control Research Programme). (au) 173 refs.

  11. Analysis of the chemical equilibrium of combustion at constant volume

    Directory of Open Access Journals (Sweden)

    Marius BREBENEL

    2014-04-01

    Full Text Available Determining the composition of a mixture of combustion gases at a given temperature is based on chemical equilibrium, when the equilibrium constants are calculated on the assumption of constant pressure and temperature. In this paper, an analysis of changes occurring when combustion takes place at constant volume is presented, deriving a specific formula of the equilibrium constant. The simple reaction of carbon combustion in pure oxygen in both cases (constant pressure and constant volume is next considered as example of application, observing the changes occurring in the composition of the combustion gases depending on temperature.

  12. Update on Engine Combustion Research at Sandia National Laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Jay Keller; Gurpreet Singh

    2001-05-14

    The objectives of this paper are to describe the research efforts in diesel engine combustion at Sandia National Laboratories' Combustion Research Facility and to provide recent experimental results. We have four diesel engine experiments supported by the Department of Energy, Office of Heavy Vehicle Technologies: a one-cylinder version of a Cummins heavy-duty engine, a diesel simulation facility, a one-cylinder Caterpillar engine to evaluate combustion of alternative fuels, and a homogeneous-charge, compression ignition (HCCI) engine. Recent experimental results of diesel combustion research will be discussed and a description will be given of our HCCI experimental program and of our HCCI modeling work.

  13. Review of Membrane Oxygen Enrichment for Efficient Combustion

    Science.gov (United States)

    Ariono, Danu; Kusuma Wardani, Anita

    2017-07-01

    Oxygen enrichment from air is a simple way of increasing the efficiency of combustion process, as in oxy-combustion. Oxy-combustion has become one of the most attracting combustion technologies because of its potential to address both pollutant reduction and CO2 capture. In oxy-combustion, the fuel and recycled flue gas are combusted with oxygen enriched air (OEA). By using OEA, many benefits can be obtained, such as increasing available heat, improving ignition characteristics, flue gas reduction, increasing productivity, energy efficiency, turndown ratio, and flame stability. Membrane-based gas separation for OEA production becomes an attractive technology over the conventional technology due to the some advantages, including low capital cost, low energy consumption, compact size, and modularity. A single pass through membrane usually can enrich O2 concentration in the air up to 35% and a 50% concentration can be achieved with a double pass of membrane. The use of OEA in the combustion process eliminates the presence of nitrogen in the flue gas. Hence, the flue gas is mainly composed of CO2 and condensable water that can be easily separated. This paper gives an overview of oxy-combustion with membrane technology for oxygen enrichment process. Special attention is given to OEA production and the effect of OEA to the efficiency of combustion.

  14. Advanced combustion turbines and cycles: An EPRI perspective

    Energy Technology Data Exchange (ETDEWEB)

    Touchton, G.; Cohn, A. [Electric Power Research Institute, Palo Alto, CA (United States)

    1995-10-01

    EPRI conducts a broad program of research in combustion turbine technology on behalf of its funders which is directed toward improving their competitive positions through lower cost of generation and risk mitigation. The major areas of EPRI interest are: (1) Combustion Turbine Technology Development, Assessment, and Procurement Information and Products. (2) Risk mitigation of emerging combustion turbines through durability surveillance. (3) Existing Fleet Management and Improvement Technology. In the context of the DOE ATS Review, the present paper will address new advanced turbines and cycles and durability surveillance, of emerging combustion turbines. It will touch on existing fleet management and improvement technology as appropriate.

  15. FY 1994 annual report. Advanced combustion science utilizing microgravity

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-10-01

    Researches on combustion in microgravity were conducted to develop combustion devices for advanced combustion techniques, and thereby to cope with the requirements for diversification of energy sources and abatement of environmental pollution by exhaust gases. This project was implemented under the research cooperation agreement with US's NASA, and the Japanese experts visited NASA's test facilities. NASA's Lewis Research Center has drop test facilities, of which the 2.2-sec drop test facilities are useful for researches by Japan. The cooperative research themes for combustion in microgravity selected include interactions between fuel droplets, high-pressure combustion of binary fuel sprays, and ignition and subsequent flame propagation in microgravity. An ignition test equipment, density field measurement equipment and flame propagation test equipment were constructed in Japan to conduct the combustion tests in microgravity for, e.g., combustion and evaporation of fuel droplets, combustion characteristics of liquid fuels mixed with solid particles, combustion of coal/oil mixture droplets, and estimating flammability limits. (NEDO)

  16. The John Zink Hamworthy combustion handbook, v.1 fundamentals

    CERN Document Server

    Baukal, Charles E

    2012-01-01

    Despite the length of time it has been around, its importance, and vast amounts of research, combustion is still far from being completely understood. Environmental, cost, and fuel consumption issues add further complexity, particularly in the process and power generation industries. Dedicated to advancing the art and science of industrial combustion, The John Zink Hamworthy Combustion Handbook, Second Edition: Volume One - Fundamentals gives you a strong understanding of the basic concepts and theory. Under the leadership of Charles E. Baukal, Jr., top combustion engineers and technologists f

  17. Practical Multi-Disciplinary Analysis Tools for Combustion Devices Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The use of multidisciplinary analysis (MDA) techniques for combustion device environment prediction, including complex fluid mixing phenomena, is now becoming...

  18. Numerical analysis of in situ combustion with diverse well configuration

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcelos, Hilma; Oliveira, Lucas; Ferraz, Handrey; Almeida, Murilo [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil)

    2008-07-01

    In situ combustion is a thermal recovery technique where energy is generated by a combustion front, and this front is propagated along the reservoir by air injection. Numerical investigation of an in situ combustion process is studied here in a three dimensional reservoir, using the STARS simulator (Computer Modeling Group - CMG, Canada), with three different well configurations: vertical injection and vertical production wells (VIVP), vertical injection and horizontal production wells (THAI), and horizontal injection and horizontal production wells (HIHP). Both dry and wet combustion processes are studied. It was found that HIHP yields the best oil recovery factor for dry combustion, followed by THAI. For wet combustion processes all three configurations yield, in the long range, the same oil recovery factor. When comparing dry and wet combustions, it was found that wet combustion offers the advantages of higher oil recovery and higher combustion front velocity for THAI and VIVP. For HIHP, the improvement of the oil recovery factor was greater for earlier years, but was not significant in the long range. (author)

  19. Combustibility Determination for Cotton Gin Dust and Almond Huller Dust.

    Science.gov (United States)

    Hughs, Sidney E; Wakelyn, Phillip J

    2017-04-26

    It has been documented that some dusts generated while processing agricultural products, such as grain and sugar, can constitute combustible dust hazards. After a catastrophic dust explosion in a sugar refinery in 2008, the Occupational Safety and Health Administration (OSHA) initiated action to develop a mandatory standard to comprehensively address the fire and explosion hazards of combustible dusts. Cotton fiber and related materials from cotton ginning, in loose form, can support smoldering combustion if ignited by an outside source. However, dust fires and other more hazardous events, such as dust explosions, are unknown in the cotton ginning industry. Dust material that accumulates inside cotton gins and almond huller plants during normal processing was collected for testing to determine combustibility. Cotton gin dust is composed of greater than 50% inert inorganic mineral dust (ash content), while almond huller dust is composed of at least 7% inert inorganic material. Inorganic mineral dust is not a combustible dust. The collected samples of cotton gin dust and almond huller dust were sieved to a known particle size range for testing to determine combustibility potential. Combustibility testing was conducted on the cotton gin dust and almond huller dust samples using the UN test for combustibility suggested in NFPA 652.. This testing indicated that neither the cotton gin dust nor the almond huller dust should be considered combustible dusts (i.e., not a Division 4.1 flammable hazard per 49 CFR 173.124). Copyright© by the American Society of Agricultural Engineers.

  20. Influence of catalysts on pulverized coal combustion characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Xu, W.; Du, H. [Northeastern University, Shenyang (China). Dept. of Metallurgy

    1995-09-01

    The influence of various catalysts on the combustion characteristics of bituminous and anthracite coals have been investigated by examining the combustibility, SEM and XRD of combustion products in the PC combustion equipment. The results show that the catalytic effect of Fe{sup 3+}, Fe{sup 2+}, Ca{sup 2+} and CaCO{sub 3} with a little Ca{sup 2+} or Fe{sup 3+}(Fe{sup 2+}) on PC combustion is strong and better for anthracite. These catalysts increase the combustibility by 1-3% for bituminous and by 10-17% for anthracite and the optimum addition content is equal to 5-7 W%. The strengthened effect of the catalysts on PC combustion have also been confirmed by SEM morphology and X-ray diffraction patterns of char particles. The CaCO{sub 3} with a little maceration extract is a good and cheap catalyst for pulverized coal combustion and the catalytic combustion reaction is in agreement with redox and oxygen transfer mechanism. 7 refs., 6 figs., 1 tab.

  1. Soot content in a gas turbine combustion chamber

    Energy Technology Data Exchange (ETDEWEB)

    Sudarev, A.V.; Antonovsky, V.I. (VTUS - Leningrad Metal Plant - LMZ, Leningrad (USSR))

    1990-01-01

    The measurement complex within the liner space, including the determination of concentration of soot particles, gaseous products, completeness of fuel combustion, was carried out on the gas turbine combustion model. The soot distribution lengthwise the liner for the investigated class of combustors and the distillate liquid fuel was determined by means of the pressure in the combustion chamber and the air excess ratio in the liner cross-section. The design formulae for determination of the fuel combustion completeness and the soot content by the flame length are recommended.

  2. Modelaje geológico y de recursos del yacimiento Pastelillo utilizando el krigeaje de indicadores

    Directory of Open Access Journals (Sweden)

    José Q. Cuador-Gil

    2005-03-01

    Full Text Available En ocasiones la complejidad y variabilidad de un yacimiento mineral hace dificil establecer dominios geológicos homogéneos que puedan ser utilizados para aplicar control geológico a la estimación de los parámetros más relevantes. La imposibilidad de crear un modelo geológico con unidades bien definidas conduce a trabajar con poblaciones heterogéneas, lo cual degrada considerablemente la calidad de las estimaciones. Tal es el caso de Pastelillo, yacimiento de materia prima para cemento, en el que es difícil reproducir la geometría de los distintos tipos tecnológicos utilizando el método tradicional de correlación geológica. Las distintas litologías que conforman el yacimientos están completamente mezcladas tanto en el plano como en la vertical y estos frecuentes cambios faciales provocan una gran variabilidad litológica y tecnológica en el yacimiento. Teniendo en cuenta lo anterior se propone emplear un método de interpolación espacial que permita hacer estimaciones en presencia de poblaciones complejas. En el artículo se establece un modelo tecnológico y de recursos para el yacimiento Pastelillo a partir del empleo de una técnica de estimación de la geoestadística no lineal: el krigeaje de indicadores.

  3. DETERMINANTES DEL LOGRO ESCOLAR EN MÉXICO. Primeros resultados utilizando la prueba ENLACE media superior

    Directory of Open Access Journals (Sweden)

    Rafael E. de Hoyos

    2012-01-01

    Full Text Available Aunque los años de escolaridad de los mexicanos aumentaron significativamente en los pasados 20 años, la calidad del sistema educativo —un determinante importante del crecimiento económico de largo plazo— dista mucho de ser satisfactorio. Utilizando los resultados de la primera prueba estandarizada en educación media superior (ENLACE-MS, este estudio muestra que un modelo que incluye las características del hogar, individuales, institucionales y escolares puede explicar más de 40% de las diferencias observadas en las calificaciones de matemáticas. Desde el punto de vista de la política pública, los resultados de este trabajo sugieren que, a fin de aumentar la calidad de la educación, las autoridades educativas deberían concentrarse en mejorar la infraestructura escolar, la calidad de los docentes y la relación entre los estudiantes y las autoridades escolares.

  4. Biossorção de azul de metileno utilizando resíduos agroindustriais

    Directory of Open Access Journals (Sweden)

    Andressa C. Honorato

    2015-07-01

    Full Text Available O presente trabalho avaliou a capacidade de adsorção do corante azul de metileno nos resíduos da palha de milho e da bainha do palmito pupunha in natura. A caracterização dos resíduos foi determinada utilizando-se a microscopia eletrônica de varredura e espectroscopia na região do infravermelho a qual indicou a presença de grupos carboxílicos, hidroxila e carbonila. O tempo necessário para que o sistema atingisse o equilíbrio para ambos os resíduos foi de 240 min, seguindo uma cinética descrita pelo modelo de pseudo-segunda ordem. A capacidade máxima de adsorção foi de 102,8 mg g-1 para o resíduo da palha de milho, seguindo o modelo de isoterma de Langmuir e 50,9 mg g-1 para o resíduo de palmito pupunha, sendo que o modelo que melhor se ajusta foi Freundlich. Desta forma, esses resíduos são promissores para a adsorção do corante azul de metileno em efluentes.

  5. Monitoramento do processo de compressão de ibuprofeno utilizando controle estatístico

    Directory of Open Access Journals (Sweden)

    Sara Elis Bianchi

    2012-04-01

    Full Text Available O Controle Estatístico de Processo (CEP é uma ferramenta bastante utilizada para auxiliar no controle da qualidade de parâmetros físicos como peso médio, dureza e friabilidade. Através das cartas de controle é possível detectar desvios dos parâmetros do processo, reduzindo a quantidade de produtos fora da especificação e, consequentemente, os custos da produção. A avaliação de trinta lotes de ibuprofeno em uma indústria farmacêutica, utilizando controle estatístico de processo, permitiu o fornecimento de informações imprescindíveis para a investigação detalhada dos pontos críticos do processo, diagnosticando as possíveis não conformidades na etapa de compressão deste fármaco. Desta maneira, podem-se propor atividades de melhoria, através da identificação e eliminação das causas especiais de variação no processo, com a finalidade de produzir comprimidos com qualidade.

  6. Comparativo das propriedades do concreto autoadensável (CAA utilizando areia fina e cinza volante

    Directory of Open Access Journals (Sweden)

    B. F. Tutikian

    Full Text Available O objetivo deste artigo é contribuir para a tomada de decisão sobre a definição do uso de materiais finos responsáveis pela resistência à segregação do concreto auto-adensável (CAA. Neste estudo, amostras de CAA foram dosadas com cinza volante, um material pozolânico, e areia fina, que é um material não pozolânico, utilizando o método de dosagem proposto por Tutikian & Dal Molin (2007 [1]. Foi observado que a utilização de cinza volante aumentou a resistência à compressão, principalmente nas idades mais avançadas, assim como os valores de módulo de deformação e velocidade das ondas de ultrasom. Também diminuiu a penetração de íons cloretos, para os mesmos valores de resistência em comparação com os CAA com areia fina e o custo final dos CAA com cinza volante foi inferior. Foram apresentados tanto os diagramas de dosagem como os de desempenho.

  7. Cálculo del factor de efectividad utilizando colocación ortogonal sobre elementos finitos

    Directory of Open Access Journals (Sweden)

    Javier Fontalvo Alzate

    2011-02-01

    Full Text Available En el presente documento se resuelve el problema del cálculo del factor de efectividad para la transferencia de masa y calor con reacción química en un pellet catalítico utilizando una técnica adecuada especialmente para números de Thiele elevados en donde la solución se restringe a una pequeña zona muy cercana a la superficie. La técnica aprovecha la rapidez de convergencia de la colocación ortogonal y la facilidad de ubicación de elementos en zonas en donde se presentan grandes gradientes del método para las diferencias finitas. La eficiencia del método está basada en la utilización del método LV para la descomposición de matrices. Se muestran comparaciones con otros métodos numéricos de solución del problema.

  8. UTILIZANDO O MÉTODO TODIM PARA AVALIAR AS MELHORES EMPRESAS PARA TRABALHAR

    Directory of Open Access Journals (Sweden)

    Renato Teixeira da Silva

    2011-06-01

    Full Text Available Este artigo expõe uma nova proposta de ordenação das 5 melhores empresas para trabalhar em termos de qualidade do ambiente de trabalho e qualidade na gestão de pessoas utilizando-se do método TODIM como suporte científico para tal. A ordenação inicial, proposta pela revista Você/SA Exame, utiliza como método classificador o índice de felicidade no trabalho, uma soma ponderada de índices resultantes da percepção dos funcionários, das práticas da empresa e da constatação feita por jornalistas em visitas às empresas. Este trabalho, que utiliza o método TODIM, considera esses itens como critérios de avaliação e realiza uma análise comparativa das alternativas. Ao final, é executada uma comparação entre as ordenações e uma análise de sensibilidade, analisando as especificidades de cada método de ordenação e a consistência de seus resultados.

  9. del aceite superficial en aluminio utilizando plasma frío

    Directory of Open Access Journals (Sweden)

    Eneas Ramos Nascimento Neto

    2007-01-01

    Full Text Available La creciente preocupación por el desarrollo sustentable unido al aumento de la concienciación relacionada con la preservación del medio ambiente han impulsado investigaciones científicas en diversas áreas que utilizan tecnologías ambientalmente aceptables. Dentro de este contexto la tecnología de aplicación de plasma frío representa una alternativa eficiente, limpia y económica para la remoción de aceites en superficies metálicas. El objetivo de este trabajo consiste en medir la remoción del aceite de la superficie del aluminio utilizando el proceso de plasma frío. Para evaluar estos resultados se realizaron medidas de ángulo de contacto y XPS. Este trabajo trata sobre el tipo de modificación que se produce sobre superficies metálicas por la acción de plasmas.

  10. Cálculo del factor de efectividad utilizando colocación ortogonal sobre elementos finitos

    Directory of Open Access Journals (Sweden)

    Javier Fontalvo Alzate

    1999-09-01

    Full Text Available En el presente documento se resuelve el problema del cálculo del factor de efectividad para la transferencia de masa y calor con reacción química en un pellet catalítico utilizando una técnica adecuada especialmente para números de Thiele elevados en donde la solución se restringe a una pequeña zona muy cercana a la superficie. La técnica aprovecha la rapidez de convergencia de la colocación ortogonal y la facilidad de ubicación de elementos en zonas en donde se presentan grandes gradientes del método para las diferencias finitas. La eficiencia del método está basada en la utilización del método LV para la descomposición de matrices. Se muestran comparaciones con otros métodos numéricos de solución del problema.

  11. DESARROLLO DE APIO MINIMAMENTE PROCESADO FORTIFICADO CON VITAMINA E, UTILIZANDO LA INGENIERIA DE MATRICES

    Directory of Open Access Journals (Sweden)

    YISELL JOHAN MARTELO CASTAÑO

    2011-01-01

    Full Text Available El objetivo de este trabajo fue desarrollar un producto minimamente procesado fortificado con vitamina E, a partir de apio (Apium graveolens L. var.dulce, utilizando la ingenieria de matrices como metodologia de obtencion de alimentos funcionales. Trozos de apio impregnados al vacio con dl¿¿tocoferol acetato emulsificado en una solucion isotonica al vegetal de NaCl, 1,2%, fueron evaluados en funcion del tiempo de almacenamiento y el envasado (con y sin vacio, en terminos de la cuantificacion de sus propiedades fisicoquimicas, color, textura, estabilidad de la vitamina E y caracteristicas sensoriales. Se formulo la emulsion con el objetivo de adicionar teoricamente un 73% del Valor Diario Recomendado (VDR vitamina E/100 g de apio fresco y su cuantificacion se realizo por HPLC. La respuesta a la impregnacion en la matriz fue de 12,10+-1,15%, lo cual permitio alcanzar un 112% VDR vitamina E/100g apio fresco, manteniendose este contenido durante el almacenamiento de 9 dias en ambos tipos de envasado. Los parametros fisicoquimicos del producto fueron afectados por la IV, el tiempo y el envasado, manteniendo su coloracion verdosa y presentando disminucion en la firmeza. La ingenieria de matrices constituye una metodologia efectiva para el desarrollo de apio minimamente procesado adicionado con vitamina E.

  12. Laser diagnostics of plasma assisted combustion

    Science.gov (United States)

    Rao, Xing

    In this study, a microwave re-entrant cavity discharge system and a direct current (DC) plasmatron are used to investigate flame enhancement and nitric oxide (NO) formation using laser and optical diagnostics. The uniqueness of this study lies in the direct coupling concept, a novel highly efficient strategy used here for the first time. To investigate combustion dynamics of direct microwave coupled combustion, an atmospheric high-Q re-entrant cavity applicator is used to couple microwave (2.45 GHz) electromagnetic energy directly into the reaction zone of a premixed laminar methane-oxygen flame using a compact torch. When microwave energy increases, a transition from electric field enhancement to microwave plasma discharge is observed. At 6 to 10 Watts, ionization and eventually break-down occurs. 2-D laser induced fluorescence (LIF) imaging of hydroxyl radicals (OH) and carbon monoxide (CO) is conducted in the reaction zone over this transition, as well as spectrally resolved flame emission measurements. These measurements serve to monitor excited state species and derive rotational temperatures using OH chemiluminescence for a range of equivalence ratios (both rich and lean) and total flow rates. Combustion dynamics is also investigated for plasma enhanced methane-air flames in premixed and nonpremixed configurations using a transient arc DC plasmatron. Results for OH and CO PLIF also indicate the differences in stability mechanism, and energy consumption for premixed and nonpremixed modes. It is shown that both configurations are significantly influenced by in-situ fuel reforming at higher plasma powers. Parametric studies are conducted in a plasma assisted methane/air premixed flame for quantitative NO production using a DC plasmatron with PLIF imaging. Quantitative measurements of NO are reported as a function of gas flow rate (20 to 50 SCFH), plasma power (100 to 900 mA, 150 to 750 W) and equivalence ratio (0.7 to 1.3). NO PLIF images and single point NO

  13. New combustion, environment regulations: the answers for natural gas; Nouvelles reglementations, combustion, environnement: les reponses pour le gaz naturel

    Energy Technology Data Exchange (ETDEWEB)

    Le Peltier-Marc, A. [Gaz de France (GDF), 75 - Paris (France)

    1997-12-31

    This paper reports on the point of view from Gaz de France (GdF) company concerning the potential consequences of the use of natural gas in combustion systems with respect to the new regulations about combustion and environment. Details concerning the measures relative to the limitation of pollutants in small combustion installations (2 - 20 MW) are given (chimney height, SO{sub x}, NO{sub x} and dusts content in exhaust gases). (J.S.)

  14. Synthetic fuel aromaticity and staged combustion

    Energy Technology Data Exchange (ETDEWEB)

    Longanbach, J. R.; Chan, L. K.; Levy, A.

    1982-11-15

    Samples of middle and heavy SRC-II distillates were distilled into 50 C boiling point range fractions. These were characterized by measurements of their molecular weight, elemental analysis and basic nitrogen content and calculation of average molecular structures. The structures typically consisted of 1 to 3 aromatic rings fused to alicyclic rings with short, 1 to 3 carbon aliphatic side chains. The lower boiling fractions contained significant amounts (1 atom/molecule) of oxygen while the heavier fractions contained so few heteroatoms that they were essentially hydrocarbons. Laboratory scale oxidative-pyrolysis experiments were carried out at pyrolysis temperatures of 500 to 1100 C and oxygen concentrations from 0 to 100 percent of stoichiometry. Analysis of liquid products, collected in condensers cooled with liquid nitrogen showed that aromatization is a major reaction in the absence of oxygen. The oxygen-containing materials (phenolics) seem to be more resistant to thermal pyrolysis than unsubstituted aromatics. Nitrogen converts from basic to nonbasic forms at about 500 C. The nonbasic nitrogen is more stable and survives up to 700 C after which it is slowly removed. A recently constructed 50,000 Btu/hr staged combustor was used to study the chemistry of the nitrogen and aromatics. SRC II combustion was studied under fuel-rich, first-stage conditions at air/fuel ratios from 0.6 to 1.0 times stoichiometric. The chemistry of the fuel during combustion calls for further investigation in order to examine the mechanism by which HCN is evolved as a common intermediate for the formation of the nitrogen-containing gaseous combustion products. 25 references, 45 figures, 25 tables.

  15. Tolerancia al co en celdas de combustible

    Directory of Open Access Journals (Sweden)

    BIBIAN HOYOS

    2008-01-01

    Full Text Available El entendimiento completo del proceso de adsorción y posterior oxidación de moléculas de CO en platino es de fundamental importancia para el desarrollo de celdas de combustible poliméricas que operan a baja temperatura. En este trabajo se presenta una revisión de las cinco estrategias experimentales más importantes en la búsqueda de mejorar la tolerancia al CO: disminución del potencial de inicio de la reacción de oxidación, reducción de la cantidad de CO adsorbido, utilización de pequeñas cantidades de oxígeno en la corriente de alimentación al ánodo, aumento de la temperatura de operación y limpieza del CO a la entrada. Aunque se han desarrollado catalizadores bastante promisorios (PtMo y PdAu, todavía se sigue considerando a la mezcla Pt-Ru como el catalizador anódico más eficiente para combustibles que contienen 10 ppm de CO o más. La estrategia de inyectar oxígeno al ánodo parece promisoria pero requiere el desarrollo de nuevas membranas más resistentes y de la implementación de condiciones más seguras de operación de la celda. El diseño estructural de ánodos especiales con múltiples capas soportando catalizadores específicos para cada tipo de combustible puede ser una estrategia muy atractiva.

  16. Pulsed atmospheric fluidized bed combustion. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1989-11-01

    In order to verify the technical feasibility of the MTCI Pulsed Atmospheric Fluidized Bed Combustor technology, a laboratory-scale system was designed, built and tested. Important aspects of the operational and performance parameters of the system were established experimentally. A considerable amount of the effort was invested in the initial task of constructing an AFBC that would represent a reasonable baseline against which the performance of the PAFBC could be compared. A summary comparison of the performance and emissions data from the MTCI 2 ft {times} 2 ft facility (AFBC and PAFBC modes) with those from conventional BFBC (taller freeboard and recycle operation) and circulating fluidized bed combustion (CFBC) units is given in Table ES-1. The comparison is for typical high-volatile bituminous coals and sorbents of average reactivity. The values indicated for BFBC and CFBC were based on published information. The AFBC unit that was designed to act as a baseline for the comparison was indeed representative of the larger units even at the smaller scale for which it was designed. The PAFBC mode exhibited superior performance in relation to the AFBC mode. The higher combustion efficiency translates into reduced coal consumption and lower system operating cost; the improvement in sulfur capture implies less sorbent requirement and waste generation and in turn lower operating cost; lower NO{sub x} and CO emissions mean ease of site permitting; and greater steam-generation rate translates into less heat exchange surface area and reduced capital cost. Also, the PAFBC performance generally surpasses those of conventional BFBC, is comparable to CFBC in combustion and NO{sub x} emissions, and is better than CFBC in sulfur capture and CO emissions even at the scaled-down size used for the experimental feasibility tests.

  17. Combustion-Driven Oscillation in Process Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Seebold, J.G. [Chevron Corporation (Retired), 198 James Avenue, Atherton, CA 94027 (United States)

    2005-10-15

    At this moment in thousands of process heaters all over the world there are, to borrow a phrase from the late Carl Sagan, 'billions and billions' of Btu/hr beneficially being released entirely free of pulsation. On those few occasions, perhaps a dozen and a half in my career, when I would get the inevitable 'Why me?' call, I have generally responsed with something like, 'Consider yourself lucky, you have a rare scientific curiosity on your hands'. Reflecting on the solutions ultimately found, I'm reminded that many years ago my friend Abbott Putnam shared with me an early AGA (American Gas Association) field-service bulletin that included a prescription for eliminating combustion-driven oscillations in home heating units; viz., 'Drill a hole; if that doesn't work, drill another hole' or words to that effect. Many times have I wished that I still had a copy of that bulletin and in this paper we will have occasion, once again, to reflect upon the value of that advice. In this paper we will discuss an instance that arose in a pioneering installation of a breakthrough development of 'extremely', to distinguish it from 'ultra', low-NOx lean premix burner technology. We will illustrate how, when and under what circumstances combustion-driven oscillation can arise; we will touch on the many alternatives for its elimination that were considered and investigated; and we will discuss three practical alternatives for eliminating combustion-driven oscillations.

  18. New experience of forest fuel combustion

    Energy Technology Data Exchange (ETDEWEB)

    Haemaelaeinen, J.; Vainikka, P.; Aho, M.; Kaerki, J. (VTT Technical Research Centre of Finland, Jyvaeskylae (Finland)), e-mail: jouni.hamalainen@vtt.fi, e-mail: pasi.vainikka@vtt.fi, e-mail: martti.aho@vtt.fi, e-mail: janne.karki@vtt.fi

    2010-07-01

    The main global drivers of the energy system are growth of energy demand due to increasing population and economic output and, on the other hand, challenges linked to energy security and mitigation of environmental impacts. It is estimated by the International Energy Agency (IEA)that global primary energy demand will increase by 50 % between now and 2030, and over 70 % of this increase will come from developing countries, especially from China and India. The increase in the use of energy has lead to considerable emissions of greenhouse gases, which are belived to warm the climate of the Earth and to cause remarkable damages to ecosystems. principally, there are three ways to reduce greenhouse gas emissions. First, one can substitute the use of fossil fuels by non-CO{sub 2}-producing sources like renewables, bioenergy or nuclear power. The second way of reducing emissions is to utilise technology with higher efficiency, i.e. to produce the same amount of energy with less fuel or to save the use of energy in end-use. The third option is to utilise so-called carbon capture technologies (CCS-technologies) that are under development at the moment. Typically use of solid biomass for power or heat and power generation is a local solution but anyway can be significant in local power generation infrastructure. Biomass can be utilised with several ways. The options are direct combustion of biomass or cocombustion it with coal or other fuels with different combustion technologies. Fluidized bed combustion, however, is the technology that allows widest fuel flexibility and high efficiency. These are the parameters with very high importance for the plant operator at future energy markets. The increased use of biomass means, however, that the quality of the fuels will become lower causing new challenges to boiler design and challenges for plant operation. These aspects are discussed in this paper. (orig.)

  19. Combustion D'une Goutte en Milieu Reactif Avec Decomposition Exothermique Prealable du Combustible

    Science.gov (United States)

    Scherrer, Dominique

    Dans de nombreuses chambres de combustion (moteur Diesel, moteur fusée,...), la valeur élevée de la pression ou la présence de fluctuations thermodynamiques ou chimiques très rapides interdisent de négliger l'aspect instationnaire dans l'évaporation et la combustion des gouttes. Par ailleurs, beaucoup de combustibles se décomposent avant de réagir avec l'oxydant, ce qui peut modifier sensiblement le taux d'évaporation. Dans ces conditions, le modèle classique conduisant à la "loi du d2" est insuffisant. On présente ici un modèle numérique monodimensionnel instationnaire permettant de prendre en compte la décomposition du combustible. La méthode utilisée est une méthode de volumes finis entièrement implicite, ce qui permet de supprimer les critères de stabilité des méthodes explicites : on a pu choisir le pas de temps et le pas d'espace, en se basant uniquement sur les temps caractéristiques les plus longs, sans que les phénomènes les plus rapides (réactions chimiques, par exemple) n'entrainent d'instabilités numériques, bien que certains soient fortement non linéaires.

  20. CO{sub 2} capture from coal combustion using chemical-looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Tobias Mattisson; Francisco Garcia-Labiano; Bernhard Kronberger; Anders Lyngfelt; Juan Adanez; Hermann Hofbauer [Chalmers University of Technology, Goeteborg (Sweden). Department of Energy and Environment, Division of Energy Technology

    2006-07-01

    Chemical-looping combustion (CLC) is a combustion technology where an oxygen carrier is used to transfer oxygen from the combustion air to the fuel, thus avoiding direct contact between air and fuel. Thus, CO{sub 2} and H{sub 2}O are inherently separated from the rest of the flue gases, and no major energy is expended for this separation. The paper presents results from a three year project devoted to developing the CLC technology for use with syngas from coal combustion. The project has focused on i) the development of oxygen carrier particles, ii) establishing a reactor design and feasible operating conditions and iii) construction and operation of a continuously working hot reactor. Approximately 300 different oxygen carriers based on oxides of the metals Ni, Fe, Mn and Cu were investigated with respect to parameters which are important in a CLC system, and from these investigations, several particles were found to possess suitable qualities as oxygen carriers. Several cold-model prototypes of CLC based on interconnected fluidized beds were tested, and from these tests a hot prototype CLC reactor system was constructed and operated successfully using three carriers based on Ni, Fe and Mn developed within the project for 30-70 h. 8 refs., 5 figs.

  1. Combustion Gases And Heat Release Analysis During Flame And Flameless Combustion Of Wood Pellets

    Directory of Open Access Journals (Sweden)

    Horváth Jozef

    2015-06-01

    Full Text Available With the growing prices of fossil fuels, alternative fuels produced of biomass come to the fore. They are made of waste materials derived from the processing of wood and wood materials. The main objective of this study was to analyse the fire-technical characteristics of wood pellets. The study analysed three dust samples acquired from wood pellets made of various types of wood biomass. Wood pellet dust is produced when manipulating with pellets. During this process a potentially hazardous situations may occur. Biomass is chemically composed mostly of hemicellulose, cellulose and lignin. During straining of the biomass by heat flux, combustion initiation occurs. Also, there was a change in the composition of material throughout combustion gases production, and the amount of heat generated by a flame or flameless combustion. Measurement of fire characteristics was conducted according to ISO 5660-1 standard using a cone calorimeter. Two samples of wood pellet dust were tested under the heat flux of 35 kW.m−2 and 50 kW.m−2. The process of combustion, the time to ignition, the carbon monoxide concentration and the amount of released heat were observed.

  2. Combustion stability with baffles, absorbers and velocity sensitive combustion. [liquid propellant rocket combustors

    Science.gov (United States)

    Mitchell, C. E.

    1980-01-01

    Analytical and computational techniques were developed to predict the stability behavior of liquid propellant rocket combustors using damping devices such as acoustic liners, slot absorbers, and injector face baffles. Models were developed to determine the frequency and decay rate of combustor oscillations, the spatial and temporal pressure waveforms, and the stability limits in terms of combustion response model parameters.

  3. Combustion instability mitigation by magnetic fields

    Science.gov (United States)

    Jocher, Agnes; Pitsch, Heinz; Gomez, Thomas; Bonnety, Jérôme; Legros, Guillaume

    2017-06-01

    The present interdisciplinary study combines electromagnetics and combustion to unveil an original and basic experiment displaying a spontaneous flame instability that is mitigated as the non-premixed sooting flame experiences a magnetic perturbation. This magnetic instability mitigation is reproduced by direct numerical simulations to be further elucidated by a flow stability analysis. A key role in the stabilization process is attributed to the momentum and thermochemistry coupling that the magnetic force, acting mainly on paramagnetic oxygen, contributes to sustain. The spatial local stability analysis based on the numerical simulations shows that the magnetic field tends to reduce the growth rates of small flame perturbations.

  4. Combustion aerosols from potassium-containing fuels

    Energy Technology Data Exchange (ETDEWEB)

    Balzer Nielsen, Lars

    1998-12-31

    The scope of the work presented in this thesis is the formation and evolution of aerosol particles in the submicron range during combustion processes, in particular where biomass is used alone or co-fired with coal. An introduction to the formation processes of fly ash in general and submicron aerosol in particular during combustion is presented, along with some known problems related to combustion of biomass for power generation. The work falls in two parts. The first is the design of a laboratory setup for investigation of homogeneous nucleation and particle dynamics at high temperature. The central unit of the setup is a laminar flow aerosol condenser (LFAC), which essentially is a 173 cm long tubular furnace with an externally cooled wall. A mathematical model is presented which describes the formation and evolution of the aerosol in the LFAC, where the rate of formation of new nuclei is calculated using the so-called classical theory. The model includes mass and energy conservation equations and an expression for the description of particle growth by diffusion. The resulting set of nonlinear second-order partial differential equations are solved numerically using the method of orthogonal collocation. The model is implemented in the FORTRAN code MONAERO. The second part of this thesis describes a comprehensive investigation of submicron aerosol formation during co-firing of coal and straw carried out at a 380 MW{sub Th} pulverized coal unit at Studstrup Power Plant, Aarhus. Three types of coal are used, and total boiler load and straw input is varied systematically. Straw contains large amounts of potassium, which is released during combustion. Submicron aerosol is sampled between the two banks of the economizer at a flue gas temperature of 350 deg. C using a novel ejector probe. The aerosol is characterized using the SMPS system and a Berner-type low pressure impactor. The chemical composition of the particles collected in the impactor is determined using

  5. Studies of combustion kinetics and mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Gutman, D. [Catholic Univ. of America, Washington, DC (United States)

    1993-12-01

    The objective of the current research is to gain new quantitative knowledge of the kinetics and mechanisms of polyatomic free radicals which are important in hydrocarbon combustion processes. The special facility designed and built for these (which includes a heatable tubular reactor coupled to a photoionization mass spectrometer) is continually being improved. Where possible, these experimental studies are coupled with theoretical ones, sometimes conducted in collaboration with others, to obtain an improved understanding of the factors determining reactivity. The decomposition of acetyl radicals, isopropyl radicals, and n-propyl radicals have been studied as well as the oxidation of methylpropargyl radicals.

  6. 2009 Laser Diagnostics in Combustion GRC

    Energy Technology Data Exchange (ETDEWEB)

    Sick, Volker [Univ. of Michigan, Ann Arbor, MI (United States)

    2009-08-16

    Non-intrusive laser diagnostics for the spatially and temporally resolved measurement of temperature, chemical composition, and flow parameters have emerged over the last few decades as major tools for the study of both fundamental and applied combustion science. Many of the important advances in the field can be attributed to the discussions and ideas emanating from this meeting. This conference, originating in 1981 and held biennially, focuses on laser-based methods for measurement of both macroscopic parameters and the underlying microscale physical and chemical processes. Applications are discussed primarily to elucidate new chemical and physical issues and/or interferences that need to be addressed to improve the accuracy and precision of the various diagnostic approaches or to challenge the community of diagnosticians to invent new measurement techniques. Combustion environments present special challenges to the optical diagnostics community as they address measurements relevant to turbulence, spray and mixture formation, or turbulence/chemistry interactions important in practical combustion systems as well as fundamental chemical reactions in stationary laminar flames. The diagnostics considered may be generally classed as being incoherent, where the signals are radiated isotropically, or coherent, where the signals are generated in a directed, beam-like fashion. Both of the foregoing may employ either electronic or Raman resonance enhancement or a combination of both. Prominent incoherent approaches include laser induced fluorescence (LIF), spontaneous Raman scattering, Rayleigh scattering, laser induced incandescence, molecular flow tagging, and Mie scattering and their two- and three-dimensional imaging variants. Coherent approaches include coherent anti-Stokes Raman scattering (CARS), degenerate four wave mixing (DFWM), polarization spectroscopy (PS), laser induced grating spectroscopy (LIGS) and laser-based absorption spectroscopy. Spectroscopic

  7. Holographic Investigation of Solid Propellant Combustion

    Science.gov (United States)

    1988-12-01

    IITLE (B=m* £Se-T) CaruatwICi, HOLOGRAPHIC INIL’ESTIGWI’ION OF SOLZ ’PROPELLANT COMBUSTION 12 PERSONAL AUTHOR(S) -Butler, Albert G. 13a TYPE OF REPORT...Speckle 19 ABSTRACT (Ccin1,rn WI ree~rse if IlCCenr~y anld ,dentify by blod number) An Investigcation into the behavior of aissmnied solid propellant...required to obtain a good quality hologram. Nuetral density filters, :3 placed in the scene beam for collimated type transmission holograms or in the

  8. Chemical Looping Combustion of Rice Husk

    OpenAIRE

    Rashmeet Singh Monga; Ganesh R. Kale

    2015-01-01

    A thermodynamic investigation of direct chemical looping combustion (CLC) of rice husk is presented in this paper. Both steam and CO2 are used for gasification within the temperature range of 500–1200˚C and different amounts of oxygen carriers. Chemical equilibrium model was considered for the CLC fuel reactor. The trends in product compositions of the fuel reactor, were determined. Rice husk gasification using 3 moles H2O and 0 moles CO2 per mole carbon (in rice husk) at 1 bar pr...

  9. Retro-fitting post combustion capture

    Energy Technology Data Exchange (ETDEWEB)

    Louis Wibberley; Doug Palfreyman; Peter Scaife [CSIRO Energy Technology (Australia)

    2008-02-15

    This report gives a technical assessment of the issues of retro-fitting post combustion capture to Australian coal fired power stations. It includes a description of the various capture technologies, their status and development timeline, and the implications for Australian power stations. A more detailed assessment is given for current and near future best available technology in both retro-fit and new applications. This is followed by a detailed thermodynamic assessment of the heat integration of solvent based PCC for a 450 MW power plant, with sensitivities for a range of key parameters. 50 refs., 66 figs.

  10. Fluidised-bed combustion of gasification residue

    Energy Technology Data Exchange (ETDEWEB)

    Korpela, T.; Kudjoi, A.; Hippinen, I.; Heinolainen, A.; Suominen, M.; Lu Yong [Helsinki Univ. of Technology (Finland). Lab of Energy Economics and Power Plant Engineering

    1996-12-01

    Partial gasification processes have been presented as possibilities for future power production. In the processes, the solid materials removed from a gasifier (i.e. fly ash and bed material) contain unburnt fuel and the fuel conversion is increased by burning this gasification residue either in an atmospheric or a pressurised fluidised-bed. In this project, which is a part of European JOULE 2 EXTENSION research programme, the main research objectives are the behaviour of calcium and sulphur compounds in solids and the emissions of sulphur dioxide and nitrogen oxides (NO{sub x} and N{sub 2}O) in pressurised fluidised-bed combustion of gasification residues. (author)

  11. Geoacoustic inversion using combustive sound source signals.

    Science.gov (United States)

    Potty, Gopu R; Miller, James H; Wilson, Preston S; Lynch, James F; Newhall, Arthur

    2008-09-01

    Combustive sound source (CSS) data collected on single hydrophone receiving units, in water depths ranging from 65 to 110 m, during the Shallow Water 2006 experiment clearly show modal dispersion effects and are suitable for modal geoacoustic inversions. CSS shots were set off at 26 m depth in 100 m of water. The inversions performed are based on an iterative scheme using dispersion-based short time Fourier transform in which each time-frequency tiling is adaptively rotated in the time-frequency plane, depending on the local wave dispersion. Results of the inversions are found to compare favorably to local core data.

  12. Computing Instability In Combustion Of Liquid Propellants

    Science.gov (United States)

    Chen, Yen-Sen; Shang, Huan-Min

    1995-01-01

    Computational fluid dynamics (CFD) code developed for use in design analyses of flow instabilities associated with combustion of sprayed liquid propellants in rocket engines. Code also contributes to design of improved commercial sprayed-fuel combustors in furnaces and jet engines. Proves robust, user-friendly software tool with comprehensive analysis capability. Enables characterization of stability or instability of engine in terms of such physically meaningful parameters as initial conditions of spray, spatial distribution of ratio between concentrations of fuel and oxidizer at injector faces, geometry of combustor, and configurations of baffles.

  13. Catalytic combustion with incompletely vaporized residual fuel

    Science.gov (United States)

    Rosfjord, T. J.

    1981-01-01

    Catalytic combustion of fuel lean mixtures of incompletely vaporized residual fuel and air was investigated. The 7.6 cm diameter, graded cell reactor was constructed from zirconia spinel substrate and catalyzed with a noble metal catalyst. Streams of luminous particles exited the rector as a result of fuel deposition and carbonization on the substrate. Similar results were obtained with blends of No. 6 and No. 2 oil. Blends of shale residual oil and No. 2 oil resulted in stable operation. In shale oil blends the combustor performance degraded with a reduced degree of fuel vaporization. In tests performed with No. 2 oil a similar effect was observed.

  14. Decrease of noxious emissions in the residual fuel oil combustion; Disminucion de emisiones nocivas en la combustion de aceite combustible residual

    Energy Technology Data Exchange (ETDEWEB)

    Mandoki W, Jorge [Econergia S. de R. L. de C. V. Mexico, D. F. (Mexico)

    1994-12-31

    The residual fuel oil combustion emits noxious substances such as carbonaceous particulate, nitrogen oxides, and sulfur trioxide at unacceptable levels. Water emulsified in the fuel substantially reduces such emissions, achieving besides, in most of the cases, a net saving in the fuel consumption. The beneficial effects are shown in burning the residual fuel oil as a water emulsion, as well as the method to produce an adequate emulsion. The emulsified fuel technology offers a low cost option to reduce air pollution. The fuel oil quality has been declining during the last decades due to: 1. Increase in the production of crude heavy oils, generally with higher content of asphaltens and sulfur. 2. Less availability of vacuum distillation residues due to its conversion into greater value products. 3. More intensive conversion processes such as catalytic cracking, visbreaking, etc. that increase the asphaltenes concentration in the bottoms, causing instability problems. 4. The increase in the vanadium and other metals content as the concentration of asphaltenes increases. The use of emulsified fuel oil provides an efficient and economical method to substantially reduce the noxious emissions to the atmosphere. The emulsion contains water particles in a diameter between 2 and 20 microns, uniformly distributed in the fuel oil, generally in a proportion generally of 5 to 10%; besides, it contains a tensioactive agent to assure a stable emulsion capable of withstanding the shearing forces of the pumping and distribution systems. When the atomized oil drops get into the combustion chamber, the emulsified water flashes into high pressure steam, originating a violent secondary atomization. The effect of this secondary atomization is the rupture of the oil drops of various hundred microns, producing drops of 5 to 15 microns in diameter. Since the necessary time for combustion is an exponential function of the drop diameter, a very substantial improvement in the combustion is

  15. Spray combustion of Jet-A and diesel fuels in a constant volume combustion chamber

    KAUST Repository

    Jing, Wei

    2015-01-01

    This work investigates the spray combustion of Jet-A fuel in an optical constant-volume combustion chamber under different ambient initial conditions. Ambient temperature was varied at 800 K, 1000 K, and 1200 K and five different ambient O2 concentrations were used, spanning 10-21%. These ambient conditions can be used to mimic practical diesel engine working conditions under different fuel injection timings and exhaust gas recirculation (EGR) levels. Both transient and quasi-steady state analyses were conducted. The transient analysis focused on the flame development from the beginning to the end of the combustion process, illustrating how the flame structure evolves with time. The quasi-steady state analysis concentrated on the stable flame structure and compared the flame emissions in terms of spatially integrated intensity, flame effective area, and intensity per pixel. The transient analysis was based on measurements using high-speed imaging of both OH∗ chemiluminescence and broadband natural luminosity (NL). For the quasi-steady state analysis, three flame narrow-band emissions (OH∗ at 310 nm, Band A at 430 nm and Band B at 470 nm) were captured using an ICCD camera. Based on the current Jet-A data and diesel data obtained from previous experiments, a comparison between Jet-A and diesel was made in terms of flame development during the transient state and spatially integrated intensity, flame effective area, and intensity per pixel during the quasi-steady state. For the transient results, Jet-A shares a similar flame development trend to diesel, but featuring a narrower region of NL and a wider region of OH∗ with the increase of ambient temperature and O2 concentration. The soot cloud is oxidized more quickly for Jet-A than diesel at the end of combustion, evident by comparing the area of NL, especially under high O2 concentration. The quasi-steady state results suggest that soot is oxidized effectively under high O2 concentration conditions by the

  16. Effect of combustion chamber geometry on performance, combustion, and emission of direct injection diesel engine with ethanol-diesel blend

    Directory of Open Access Journals (Sweden)

    Gnanamoorthi Venkadesan

    2016-01-01

    Full Text Available In the present paper, the effect of combustion chamber geometry on performance, combustion and emissions of ethanol-diesel blend operated in direct injection Diesel engine is discussed. The main air motions are generated in the cylinder by the intake - induced swirl, the piston motion, and its geometry. The piston bowl is modified from traditional hemispherical combustion chamber to the toroidal (re-en-trant combustion chamber and operated with Neat diesel and 40% ethanol diesel blend to improve better evaporation and mixing during the compression stroke on a single cylinder Diesel engine. It is found that the toroidal combustion chamber creates better turbulence, squish, and swirl at high compression ratios of 19.5:1 compared to that of traditional one. Further, the combustion is significantly enhanced due to increased swirl. It is concluded that the brake thermal efficiency for toroidal combustion chamber is 33% and the peak pressure in the cylinder as well as peak heat release rate is also increased. Further, it is also concluded that 60% of CO emission, 20% of HC emission, 40% of NOx emission, and 90% in smoke emissions were reduced for toroidal combustion chamber, compared to that of hemispherical combustion chamber.

  17. Experimental study of combustion and emission characteristics of ethanol fuelled port injected homogeneous charge compression ignition (HCCI) combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Maurya, Rakesh Kumar; Agarwal, Avinash Kumar [Engine Research Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur 208 016 (India)

    2011-04-15

    The homogeneous charge compression ignition (HCCI) is an alternative combustion concept for in reciprocating engines. The HCCI combustion engine offers significant benefits in terms of its high efficiency and ultra low emissions. In this investigation, port injection technique is used for preparing homogeneous charge. The combustion and emission characteristics of a HCCI engine fuelled with ethanol were investigated on a modified two-cylinder, four-stroke engine. The experiment is conducted with varying intake air temperature (120-150 C) and at different air-fuel ratios, for which stable HCCI combustion is achieved. In-cylinder pressure, heat release analysis and exhaust emission measurements were employed for combustion diagnostics. In this study, effect of intake air temperature on combustion parameters, thermal efficiency, combustion efficiency and emissions in HCCI combustion engine is analyzed and discussed in detail. The experimental results indicate that the air-fuel ratio and intake air temperature have significant effect on the maximum in-cylinder pressure and its position, gas exchange efficiency, thermal efficiency, combustion efficiency, maximum rate of pressure rise and the heat release rate. Results show that for all stable operation points, NO{sub x} emissions are lower than 10 ppm however HC and CO emissions are higher. (author)

  18. Burning Questions in Gravity-Dependent Combustion Science

    Science.gov (United States)

    Urban, David; Chiaramonte, Francis P.

    2012-01-01

    Building upon a long history of spaceflight and ground based research, NASA's Combustion Science program has accumulated a significant body of accomplishments on the ISS. Historically, NASAs low-gravity combustion research program has sought: to provide a more complete understanding of the fundamental controlling processes in combustion by identifying simpler one-dimensional systems to eliminate the complex interactions between the buoyant flow and the energy feedback to the reaction zone to provide realistic simulation of the fire risk in manned spacecraft and to enable practical simulation of the gravitational environment experienced by reacting systems in future spacecraft. Over the past two decades, low-gravity combustion research has focused primarily on increasing our understanding of fundamental combustion processes (e.g. droplet combustion, soot, flame spread, smoldering, and gas-jet flames). This research program was highly successful and was aided by synergistic programs in Europe and in Japan. Overall improvements were made in our ability to model droplet combustion in spray combustors (e.g. jet engines), predict flame spread, predict soot production, and detect and prevent spacecraft fires. These results provided a unique dataset that supports both an active research discipline and also spacecraft fire safety for current and future spacecraft. These experiments have been conducted using the Combustion Integrated Rack (CIR), the Microgravity Science Glovebox and the Express Rack. In this paper, we provide an overview of the earlier space shuttle experiments, the recent ISS combustion experiments in addition to the studies planned for the future. Experiments in combustion include topics such as droplet combustion, gaseous diffusion flames, solid fuels, premixed flame studies, fire safety, and super critical oxidation processes.

  19. Mixing and combustion enhancement of Turbocharged Solid Propellant Ramjet

    Science.gov (United States)

    Liu, Shichang; Li, Jiang; Zhu, Gen; Wang, Wei; Liu, Yang

    2018-02-01

    Turbocharged Solid Propellant Ramjet is a new concept engine that combines the advantages of both solid rocket ramjet and Air Turbo Rocket, with a wide operation envelope and high performance. There are three streams of the air, turbine-driving gas and augment gas to mix and combust in the afterburner, and the coaxial intake mode of the afterburner is disadvantageous to the mixing and combustion. Therefore, it is necessary to carry out mixing and combustion enhancement research. In this study, the numerical model of Turbocharged Solid Propellant Ramjet three-dimensional combustion flow field is established, and the numerical simulation of the mixing and combustion enhancement scheme is conducted from the aspects of head region intake mode to injection method in afterburner. The results show that by driving the compressed air to deflect inward and the turbine-driving gas to maintain strong rotation, radial and tangential momentum exchange of the two streams can be enhanced, thereby improving the efficiency of mixing and combustion in the afterburner. The method of injecting augment gas in the transverse direction and making sure the injection location is as close as possible to the head region is beneficial to improve the combustion efficiency. The outer combustion flow field of the afterburner is an oxidizer-rich environment, while the inner is a fuel-rich environment. To improve the efficiency of mixing and combustion, it is necessary to control the injection velocity of the augment gas to keep it in the oxygen-rich zone of the outer region. The numerical simulation for different flight conditions shows that the optimal mixing and combustion enhancement scheme can obtain high combustion efficiency and have excellent applicability in a wide working range.

  20. 77 FR 60341 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2012-10-03

    ... Emission Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines to..., ``National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New... pollutants (NESHAP) for stationary reciprocating internal combustion engines (RICE), as well as other...