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Sample records for combustible alimentadas con

  1. Poblaciones microbianas ruminales en novillas alimentadas con Leucaena leucocephala en el Bosque Seco Tropical colombiano.

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    Erika Angarita

    2015-05-01

    Full Text Available La fermentación y metanogénesis ruminal son procesos metabolicos vitales para los bovinos y son llevados a cabo por poblaciones microbianas, las cuales se afectan por factores como la presencia de metabolitos secundarios, la composición nutricional y la degradabilidad de la dieta. El objetivo de este trabajo fue monitorear las poblaciones de bacterias totales, metanógenos totales y Butirivibrio fibrisolvens en el rumen de novillas raza Lucerna, alimentadas con dietas típicas de un sistema silvopastoril intensivo y un sistema tradicional. Para ello, se colectó contenido ruminal (CR por vía oral a ocho novillas que consumían 100% Cynodon plectostachyus (control y 76% C. plectostachyus + 24% Leucaena leucocephala siguiendo un diseño de sobre-cambio. A partir del CR se extrajo y cuantificó ADN mediante PCR cuantitativa. Las poblaciones [Log10 (ng/g CR] fueron 5.6 y 5.8 para bacterias totales (P= 0.5343, 3.6 y 3.5 para B. fibrisolvens (P= 0.4742, y 5.0 y 5.3 para metanógenos totales (P= 0.2661, para la dieta control y la dieta con leucaena respectivamente. Las poblaciones monitoreadas cuantitativamente no difirieron de manera significativa con la inclusión de L. leucocephala. Esto indica la importancia de investigar la estructura, función e interacciones de las poblaciones más allá del análisis cuantitativo para determinar cómo la dieta afecta las poblaciones microbianas ruminales y su función.

  2. PIGMENTACIÓN, CRECIMIENTO Y SUPERVIVENCIA DE CRÍAS CARPA KOI (CYPRINUS CARPIO VAR. HAEMATOPTERUS ALIMENTADAS CON DIETAS CON INCLUSIONES DE ACEITE DE LANGOSTILLA ROJA (PLEURONCODES PLANIPES

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    Gloria L. Gil R.

    2015-01-01

    Full Text Available En este estudio se evaluó el efecto de la inclusión de aceite de langostilla roja (Pleuroncodes planipes sobre el crecimiento, supervivencia y pigmentación del tegumento de crías de carpa koi (Cyprinus carpio var. haematopterus. El estudio consistió en tres experimentos: experimento 1, con fotoperiodo de 4 h L / 20 h O y aguas claras; experimento 2, con fotoperiodo 12 h L/ 12 h O y aguas claras, y, experimento 3, cuyo fotoperiodo fue de 12 h L /12 O y aguas con algas. En estos experimentos, dos variedades de crías de carpa koi -naranjas y con manchas oscuras- fueron alimentadas con dietas adicionadas con aceite de langostilla a diferentes porcentajes de inclusión (0, 1, 2 y 3 %, con el 5% de alimento con relación a la biomasa de cada unidad experimental. Al final de cada uno de los experimentos se tomaron fotografías de los organismos y se analizó la coloración con el modelo de matiz-saturación-brillantez de cuatro regiones anatómicas en ambas variedades de crías y en los experimentos 1 y 2 se evaluaron parámetros biológicos: supervivencia, ganancia en longitud y en peso, y porcentaje de incremento en peso y en longitud. Las dietas adicionadas con aceite de langostilla roja no fueron rechazadas por los organismos, y no se observaron efectos negativos en las variables evaluadas. En general, la inclusión de aceite influyó en la pigmentación de las crías de color naranja y en el crecimiento y la coloración de los organismos con manchas oscuras, particularmente cuando el fotoperiodo fue de 12 L/ 12 O.

  3. Evaluación de adsorbentes para la reducción de aflatoxina M1 en leche de vacas alimentadas con dietas contaminadas artificialmente con AFB

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    Federico Rojo

    2014-01-01

    Full Text Available Los adsorbentes han sido utilizados ampliamente para prevenir las micotoxicosis y la transferencia d e toxinas o sus metabolitos dentro de la cadena alimentaria. Particularmente, se unen a las aflatoxinas dentro del tracto gastrointestinal de los rumiantes, disminuyendo su biodisponibilidad y la transferencia de aflatoxin a M 1 (AFM 1 a la leche. El presente estudio se desarrolló para evaluar dos métodos de exposición a aflatoxina B 1 en vacas Holstein y monitorear la transferencia AFM 1 a la leche. Adicionalmente, se analizó el potencial de tres adsorbentes de aflatoxinas en ambos experimentos. Los resultados mostraron una tasa de trasferencia de AFB 1 a AFM 1 / día de 3.35 y 1.8 % en los dos experimentos respectivamente. La transferencia estimada de AFM 1 en la leche observada en el segundo método fue cercana a las obtenidas de vacas alimentadas con alimentos natura lmente contaminados con aflatoxinas. A diferencia de los glucomananos de paredes cel ulares de levaduras, ambos adsorbentes de aluminosilicatos disminuyeron significativamente los niveles de AFM 1 en la leche ( P <0.05.

  4. Ingesta y evolución ponderal de ratas alimentadas con diferentes aceites crudos y fritos

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    Pérez-Granados, A. M.

    1998-04-01

    Full Text Available Olive oil, sunflower oil and palm olein, unused or used in repeated potato frying until the oils reached the limit of 25% of polar compounds (PC were used. Wistar rats were fed over 28 days diets containing 8% of: olive oil, olive oil from 48 fryings, olive oil from 69 fryings (25% PC, sunflower oil, sunflower oil from 48 fryings (25% PC, palm olein and palm olein from 80 fryings (25% PC Body weight and food intake were monitored weekly and food efficiency was calculated. At the end of the experiment the animals were sacrificed to separate the liver and calculate the hepatosomatic index. The consumption of frying oils did not modify food Intake, body weight food efficiency nor liver weight but hepatosomatic index was higher in rats consuming frying palm olein compared to unused palm olein.

    Se utilizaron aceites de oliva, girasol y oleína de palma, crudos o procedentes de frituras repetidas de patatas sin reposición de aceite hasta alcanzar el límite del 25% de compuestos polares (CP. Ratas Wistar se alimentaron durante 28 días con dietas que contenían un 8% de: aceite de oliva, aceite de oliva de 48 frituras, aceite de oliva de 69 frituras (25% CP, aceite de girasol, aceite de girasol de 48 frituras (25% CP, oleína de palma y oleína de palma de 80 frituras (25% CP. Peso e ingesta se controlaron semanalmente y se calculó el coeficiente de eficacia alimentaria. Al final del experimento los animales se sacrificaron para extraer los hígados y determinar el índice hepatosomático. El consumo de los aceites empleados en fritura no modificó la ingesta, peso, coeficiente de eficacia alimentaria ni el peso de los hígados, observándose únicamente un incremento del índice hepatosomático en los animales que ingirieron la oleína de palma frita frente a la cruda.

  5. BICULTIVO EN BIOFLOC DE CACHAMA BLANCA -Piaractus brachypomus- Y TILAPIA NILÓTICA -Oreochromis niloticus- ALIMENTADAS CON DIETAS DE ORIGEN VEGETAL

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    S. B. Brú-Cordero

    2017-01-01

    Full Text Available Se evaluó el desempeño productivo de cachama blanca y tilapia nilótica cultivadas en biofloc y alimentadas con dietas de origen vegetal. Se cultivaron 80 peces/m3 en proporción 1:1 (cachama : tilapia, con tres niveles de proteína bruta (PB: 16% (T16, 24% (T24 y 32% (T32, en tanques de 1.000 l, con aireación permanente durante 120 días. Se estimaron parámetros de crecimiento, rendimiento, calidad de agua, costos de producción y análisis proximal de los flóculos. El oxígeno disuelto se mantuvo con saturación por encima de 100% y los compuestos nitrogenados (NO2 = 0,4-0,5 mg/l, NO3 = 0,4-0,5 mg/l, NH3 = 0,2-0,3 mg/l, TAN = 2,2-2,4 mg/l no presentaron diferencias entre los tratamientos (P > 0,05. Los pesos finales de la cachama (173,5-196,2 g fueron entre dos y cuatro veces los obtenidos por la tilapia (43,0-87,9 g. El mejor rendimiento del bicultivo se obtuvo con la dieta T24 (11,4 ± 1,3 kg/m3, el cual también registró el menor FCA (0,9 ± 0,3. Producir un kilogramo de pescado costó entre COP $3.148 (T24 y COP $4.445 (T32; del cual el alimento representó entre 49,2% (T16 y 63,3% (T32 y la energía, entre 10,3% (T32 y 14,2% (T16 de los costos. El análisis proximal de los flóculos registró niveles de proteína bruta (29-36% PB adecuados para cachama y tilapia; pero con niveles bajos de lípidos (< 1,0%. El desempeño productivo y los costos de producción permiten sugerir la viabilidad que ofrece el sistema biofloc para la producción de carne de pescado con alimento de 24% PB de origen vegetal.

  6. Balance de nitrógeno y digestibilidad energética en ratas alimentadas con manteca de freidura

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    Jiménez, S.

    1992-06-01

    Full Text Available This study was carried out during 90 days in order to know the effect of frying lard on the energy digestibility and nitrogen bioavailability. A significant decrease occurred on energy utilization of the diets prepared with frying lard (52 frying times. Nitrogen bioutilization on growing rats was also affected.

    Se realiza un estudio de 90 días de duración en ratas con el fin de conocer posibles efectos de las grasas de freidura sobre el coeficiente de digestibilidad energética y la biodisponibilidad del nitrógeno. Se observó una disminución de la utilización de la energía de la dieta con el consumo reiterado de grasas con 52 freiduras y se encontró afectada la bioutilización del nitrógeno del organismo en crecimiento.

  7. Sobrevivencia, metamorfosis y crecimiento de larvas del camarón Penaeus californiensis (Decapoda: Peneidae alimentadas con diferentes microalgas

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    José Naranjo

    1999-12-01

    Full Text Available Se realizó una prueba experimental en un Centro de Producción Ostrícola en Bahía de Kino, Sonora, con el fin de evaluar el efecto de diferentes microalgas en el desarrollo de larvas de camarón café Penaeus californiensis. Las microalgas evaluadas fueron la diatomea Chaetoceros gracilis y los fitoflagelados Isochrysis galbana y Dunalliella sp., solas o en combinación y adición de nauplios de Artemia sp. a partir del estadio de zoea III, excepto en un tratamiento donde no se adicionó Artemia sp. Se utilizaron 24 unidades experimentales (tres por tratamiento, consistentes en garrafones plásticos de 16 l de capacidad, una densidad de siembra de 50 nauplios/l, una temperatura de 25°C controlada mediante calentadores sumergibles de 50 watts y una salinidad de 35 ppmil. C. gracilis produjo la mejor sobrevivencia (55%, siguiendole la combinación de C. gracilis con Dunaliella sp. (48%, la más baja sobrevivencia fue para el tratamiento donde se utilizó Dunaliella sp. fueron evidentes un retraso en la velocidad de metamorfosis para los tratamientos donde C. gracilis no fue utilizada y diferencias significativas (pThe effect of three microalgae, Chaetoceros gracilis, Isochrysis galbana, and Dunalliella sp. on the larval development of yellowleg shrimp Penaeus californiensis, was evaluated in the Oyster Production Center of Bahia Kino, Sonora, México. The effects of each microalgae (1 individually, (2 combined and (3 mixed with Artemia nauplii (from zoea III stage, were considered. Twenty four experimental units (three 16.0 l plastic bottles per treatment were used. During the experiment temperature was maintained around 25°C, and salinity around 35 ppt. The stocking density of nauplii was 50/l. The best survival was obtained with C. gracilis (55%, followed by the combination of C. gracilis and Dunalliella sp (48%. The worst survival was obtained in the treatment with Dunalliella sp. An evident delay in the metamorphosis times was observed in

  8. Combustion of drops of Mexican fuel oils with high asphaltenes content; Combustion de gotas de combustoleos mexicanos con alto contenido de asfaltenos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Rodriguez, Jose Francisco [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-09-01

    In this work the combustion of fuel drops with a content of 18% of asphaltenes has been studied . The results obtained for this fuel were compared with the ones obtained for another with a content of 12% asphaltenes. The drops were suspended in a platinum filament and burned in an spherical radiant furnace. The drop size varied between 600 and 800 microns. The fuel drops with 12% asphaltenes showed shorter combustion times, a smaller diameter increment of the smaller diameter during the combustion stages and also a shorter burning time of the carbonaceous residue than the fuel drops with a content of 18% asphaltenes. [Espanol] En el presente trabajo se ha estudiado la combustion de gotas de combustible con 18% de contenido de asfaltenos. Los resultados obtenidos para este combustible se compararon con los obtenidos para otro con 12% de contenido de asfaltenos. Las gotas fueron suspendidas en un filamento de platino y quemadas en un horno radiante esferico. El tamano de las gotas vario entre 600 y 800 micras. Las gotas de combustible con 12% de asfaltenos mostraron tiempos de combustion mas cortos, un incremento del diametro menor durante las etapas de combustion y un tiempo de quemado del residuo carbonoso tambien mas corto que las gotas del combustible con 18% de contenido de asfaltenos.

  9. COMPOSICIÓN QUIMICA DE LA LECHE, DIGESTIBILIDAD in vitro DE LA MATERIA SECA Y PRODUCCIÓN EN VACAS ALIMENTADAS CON GRAMÍNEAS SOLAS O ASOCIADAS CON Lotus uliginosus

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    A. Morales

    2013-01-01

    Full Text Available La presente investigación tuvo como objetivo evaluar el uso de la leguminosa Lotus uliginosus como alternativa de inclusión dentro de las praderas en dos ecorregiones estratégicas de la sabana de Bogotá. en cada finca se evaluaron cuatro tratamientos: 1 kikuyo solo (P. clandestinum, 2 kikuyo asociado con trébol pata de pájaro ( P.clandes-tinum + L. uliginosus, 3 festuca alta sola (F. arundinacea y 4 Festuca alta asociada con trébol pata de pájaro (F. arundinacea + L. uliginosus. el número de bovinos varió de acuerdo a la capacidad de carga de cada finca. se utilizaron animales que se encontraban en el segundo tercio de lactancia durante un período experimental de siete días. en cada tratamiento se determinó la producción (L/día y calidad de leche (% de grasa, proteína y sólidos totales; en la pastura se evaluó la composición química (Ms, Fdn, Fda y la digestibilidad in vitro de la materia seca (divMs. se midió el consumo voluntario. en la finca Megaleche la producción de biomasa presentó diferencias significativas (P<0,05 entre los tratamientos destacándose el tratamiento del kikuyo solo; la calidad nutricional de las pasturas también presentó diferencias (P<0,04 destacándose el tratamiento de kikuyo + trébol pata de pájaro, asociación que también se destacó en consumo voluntario (P< 0.05 y producción de leche (P<0,05. en la finca Colega el contenido de proteína del forraje presentó diferencias cuando las gramíneas se asociaron con el trébol pata de pájaro (P<0,001. se concluyó que la introducción del Lotus en las praderas mejoró la producción de leche y consumo de materia seca en los animales.

  10. Fuel oil combustion with low production of nitrogen oxides; Combustion de combustoleo con baja produccion de oxidos de nitrogeno

    Energy Technology Data Exchange (ETDEWEB)

    Escalera Campoverde, Rogelio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-09-01

    This work presents the results of the theoretical-experimental study of the effects of the secondary air jet directed perpendicularly to the flame axis in the fuel oil combustion in a 500 Kw furnace. The main purpose of this study was to obtain low nitrogen oxides (NO{sub x}) emissions without increasing the CO, which is observed in low NO{sub x} conventional burners. The experimental results showed a significative reduction of the NO{sub x} and of the CO, from 320 to 90 ppm and from 50 ppm to negligible values, respectively. A commercial computational code of fluid dynamics was employed for modeling the combustion in base line conditions, without secondary air and with the injection of secondary air. The experimental results were compared with calculated ones. [Espanol] En este trabajo se presentan los resultados del estudio teorico experimental de los efectos de los chorro de aire secundario dirigidos en forma perpendicular al eje de la flama en la combustion del combustoleo en un horno de 500 kW. El proposito principal del estudio fue obtener bajas emisiones de oxidos de nitrogeno (NO{sub x}) sin incrementar el CO, lo cual se observa en quemadores convencionales de bajo NO{sub x}. Los resultados experimentales demostraron una reduccion significativa del NO{sub x} y del CO: de 320 a 90 ppm y de 50 ppm a valores despreciables, respectivamente. Se empleo un codigo computacional comercial de dinamica de fluidos para modelar la combustion en condiciones de linea base, sin aire secundario, y con la inyeccion del aire secundario. Se comparan resultados experimentales con los calculados.

  11. Combustibles más limpios. Oxidar el azufre con agua oxigenada

    OpenAIRE

    Heraldo de Aragón

    2017-01-01

    Eliminar los compuestos de azufre de los combustibles mediante el empleo de agua oxigenada. Este es el planteamiento de un prometedor sistema catalítico heterogéneo, ‘made in Aragón’, que podría minimizar los efectos perjudiciales de los combustibles sobre la salud y el medio ambiente. Este desarrollo, realizado en el ISQCH en colaboración con la empresa productora de agua oxigenada Peroxychem Spain, ubicada en La Zaida, es uno de los artículos científicos de ingeniería química más citados de...

  12. Evaluación de los niveles de nitrógeno ureico en sangre de vacas Holstein en etapa post-parto alimentadas con energía de paso

    OpenAIRE

    López B., Adriana; Sari S., Claudio

    2003-01-01

    El nitrógeno ureico presente en la sangre de los bovinos en niveles normales sirve para evaluar como esta la nutrición con respecto a la proteína al relacionar la energía de paso con el nitrógeno ureico en sangre, por que a mayor consumo de proteína mayor consumo de energia de paso Magister en Producción Animal, Mención Bovinos Cuenca

  13. Eficiencia de celdas generadoras de gases oxidantes alimentadas con energía eléctrica o solar Efficiency of oxidant gas generator cells powered by electricity or solar energy

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    Héctor Brust Carmona

    1998-02-01

    Full Text Available Las enfermedades causadas por microorganismos contaminantes del agua siguen siendo un grave problema en países como México. La cloración mediante gas cloro o compuestos de cloro es uno de los mejores métodos para tratar el agua destinada al consumo humano. Sin embargo, la dificultad en el manejo del gas cloro y la ineficiencia de los sistemas de dosificación de soluciones de hipoclorito, debida a factores sociopolíticos, económicos y culturales, a veces han restado utilidad a estos procedimientos de cloración, sobre todo en comunidades rurales alejadas y de difícil acceso. Por todo ello se han desarrollado tecnologías apropiadas para la desinfección del agua mediante la generación in situ de gases oxidantes (cloro y ozono a partir de la electrólisis de una solución de sal común, el llamado sistema MOGGOD. La evaluación simulada del sistema mediante un modelo hidráulico permitió calcular sus costos parciales y totales. Con alimentación del sistema mediante energía eléctrica de la red se obtuvo una eficiencia de 90% y se generaron en 10 horas gases suficientes para desinfectar cerca de 200 m³ de agua a un costo aproximado de N$ 8 (US$ 1,30. La celda electrolítica funciona también con energía eléctrica suministrada mediante célula fotoeléctrica, en cuyo caso los costos de inversión son mayores. El sistema alimentado con células fotovoltaicas puede estar justificado en comunidades aisladas que carecen de energía eléctrica pero que cuentan con un sistema de distribución de agua por gravedad.Diseases caused by microbial contaminants in drinking water continue to be a serious problem in countries like Mexico. Chlorination, using chlorine gas or chlorine compounds, is one of the best ways to treat drinking water. However, difficulties in handling chlorine gas and the inefficiency of hypochlorite solution dosing systems--due to sociopolitical, economic, and cultural factors--have reduced the utility of these chlorination

  14. 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

  15. Combustion

    CERN Document Server

    Glassman, Irvin

    2008-01-01

    Combustion Engineering, a topic generally taught at the upper undergraduate and graduate level in most mechanical engineering programs, and many chemical engineering programs, is the study of rapid energy and mass transfer usually through the common physical phenomena of flame oxidation. It covers the physics and chemistry of this process and the engineering applications-from the generation of power such as the internal combustion automobile engine to the gas turbine engine. Renewed concerns about energy efficiency and fuel costs, along with continued concerns over toxic and particulate emissions have kept the interest in this vital area of engineering high and brought about new developments in both fundamental knowledge of flame and combustion physics as well as new technologies for flame and fuel control. *New chapter on new combustion concepts and technologies, including discussion on nanotechnology as related to combustion, as well as microgravity combustion, microcombustion, and catalytic combustion-all ...

  16. Combustion

    CERN Document Server

    Glassman, Irvin

    1997-01-01

    This Third Edition of Glassman's classic text clearly defines the role of chemistry, physics, and fluid mechanics as applied to the complex topic of combustion. Glassman's insightful introductory text emphasizes underlying physical and chemical principles, and encompasses engine technology, fire safety, materials synthesis, detonation phenomena, hydrocarbon fuel oxidation mechanisms, and environmental considerations. Combustion has been rewritten to integrate the text, figures, and appendixes, detailing available combustion codes, making it not only an excellent introductory text but also an important reference source for professionals in the field. Key Features * Explains complex combustion phenomena with physical insight rather than extensive mathematics * Clarifies postulates in the text using extensive computational results in figures * Lists modern combustion programs indicating usage and availability * Relates combustion concepts to practical applications.

  17. Pilas de combustible de una sola cámara, basadas en electrolitos de ceria dopada con gadolinia y operadas con metano y propano

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    Piñol, S.

    2010-02-01

    Full Text Available The main advantages of single-chamber solid oxide fuel cells (SOFCs respect to dual-chamber SOFCs, are to simplify the device design and to operate in mixtures of hydrocarbon (methane, propane… and air, with no separation between fuel and oxidant. However, this design requires the use of selective electrodes for the fuel oxidation and the oxidant reduction. In this work, electrolyte-supported SOFCs were fabricated using gadolinia doped ceria (GDC as the electrolyte, Ni + GDC as the anode and LSC(La0.5Sr0.5CoO3-δ-GDC-Ag2O as the cathode. The electrical properties of the cell were determined in mixtures of methane + air and propane + air. The influence of temperature, gas composition and total flow rate on the fuel cell performance was investigated. As a result, the power density was strongly increased with increasing temperature, total flow rate and hydrocarbon composition. Under optimized gas compositions and total flow conditions, power densities of 70 and 320 mW/cm2 operating on propane at a temperature of 600ºC and methane (795ºC were obtained, respectively.

    La principal ventaja de las pilas de combustible de óxido sólido (SOFCs de una sola cámara, frente a las bicamerales convencionales, es que permiten simplificar el diseño del dispositivo y operar con mezclas de hidrocarburos (metano, propano... y aire, sin necesidad de separar ambos gases, por medio del uso de electrodos selectivos a la oxidación del combustible y reducción del oxidante. En el presente trabajo, se han fabricado monopilas soportadas sobre electrolitos de ceria dopada con gadolinia (GDC, de 200 µm de espesor, usando Ni-GDC como ánodo y LSC(La0.5Sr0.5CoO3-δ-GDC-Ag2O como cátodo. Las propiedades eléctricas de la celda se determinaron en un reactor de una sola cámara, usando mezclas de metano + aire y propano + aire. Se investigó la influencia de la

  18. Balance térmico de hornos de panaderías con el empleo de gas como combustible

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    Manuel Plá Duporté

    2011-03-01

    Full Text Available En el trabajo se muestra un método para la evaluación térmica de los hornos criollos de panadería, el cual permite calculartodas las pérdidas de calor, la eficiencia y el consumo específico de combustible. Mediante este método se puedenrealizar ajustes de aquellos factores que provocan un incremento en el consumo de combustible de dichos hornos yanalizar las modificaciones y operaciones necesarias para lograr elevar la eficiencia y que sea factible la sustitución delgasoil por gas manufacturado.La evaluación realizada a estos hornos aporta datos hasta ahora desconocidos por ser esta la primera vez que se realizaun estudio usando gas manufacturado; pues en los realizados anteriormente el combustible empleado ha sido diesel.Se llevó a cabo con la ayuda de un programa de computación en Visual Basic y un programa en Excel que permitieron elanálisis de variantes, para la más adecuada valoración técnico económica que permita la toma de decisiones correctas.  In the work an analysis of the feasibility of the substitution of gas-oil for manufactured gas in the net of bakeries of theCity of Havana is made. It is carried out the energy evaluation of a national oven which uses manufactured gas as fuel.This allowed to obtain the different energy losses that take place in the same one, their efficiency and the specificconsumption of energy.This evaluation is carried out for the first time in a national oven using this type of fuel and it was carried out with thehelp of a calculation program in Visual Basic and a program in Excel that allowed the analysis of variants, all thatwith the goal of obtain the appropriate economic technic valuation that allows the taking of correct decisions.

  19. Cartografía de modelos de combustible con teledetección: aportaciones a un desarrollo ambiental sostenible

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    Riaño, David

    2001-06-01

    la teledetección espacial para obtener cartografía de modelos de combustible. Estos mapas aportan una información básica en los sistemas de prevención, predicción y modelado de incendios forestales, ya que permiten analizar las características y estructura de la vegetación de cara a la propagación del fuego. Hemos utilizado como área de estudio el Parque Nacional de Cabañeros (Ciudad Real. La cartografía de combustible se ha basado en el análisis de dos imágenes de satélite Landsat- TM, junto con información auxiliar (modelos digitales de elevación y texturas. Los resultados de la clasificación ofrecieron una precisión promedio del 83 %. Las mayores dificultades que encontramos hacen referencia a la discriminación entre las diferentes alturas del matorral y la identificación del matorral bajo el arbolado. [fr] La cartographie des modèles de combustible avec télédétection: apports pour développement environnemental durable. La conjonction entre développement et soutenance de l´environnement devient un aspect de singulière importance dans notre société. Llncidence de l'activité humaine dans l´apparition des incendies forestiers suppose un exemple net de cette affirmation, puis que les récents changes des modèles d'utilisation du territoire vont accompagnés d'une notable augmentation des incendies forestiers, avec la conséquente dégradation du sol et la couverture végétale. Dans ce contexte suite de somme importance améliorer les outils de prévention des incendies et l´évaluation de ses effets, pour réduire l'incidence ou pallier les effets de ce phénomène. Dans cet article, on présente un exemple de ce tipe de vises. En concret, nous analysons le papier de la télédétection spatiale pour obtenir cartographie des modèles de combustible. Ces cartes apportent une information basique dans les systèmes de prévention, prédiction et modelage des incendies forestiers, puis que permettent analyser les caract

  20. Inducción fúngica de la biorremediación de suelos contaminados con combustibles

    Directory of Open Access Journals (Sweden)

    Mary Lopretti

    2011-04-01

    Full Text Available La biorremediación de suelos ha sido en los últimos años una de las aplicaciones de los procesos de la biotecnología industrial que se ha desarrollado en busca de soluciones  naturales y eficientes al problema de la contaminación.Varios son los microorganismos que viven en condiciones extremas, desarrollando estrategias metabólicas que les permiten tener sus vías metabólicas aptas para vivir y reproducirse. Dentro de estas estrategias  se encuentra la acción de enzimas hidrolíticas, oxidativas y depolimerizantes que permiten modificar sustratos complejos como lo son los derivados del petróleo  y entre ellos los combustibles.En el presente trabajo se estudió la acción de dos hongos Gloeophylum trabeum y Phanerochaetes chrysosporium actuando en forma consorcial sobre sustratos  contaminados con gasoil y nafta.Se prepararon 4 reactores de fermentación sólida: dos de ellos blanco, contaminados sin inducción, y de los otros dos uno con nafta y el otro con gasoil inoculados ambos con 100cc de medio de propagación con micelios de P.chrysosporium y 50cc de medio de crecimiento con pellets de G. trabeum. Se extrajeron muestras cada 15 días y se evaluó  en el material de cada reactor características fisicoquímicas como %C, humedad y pH.También se realizó la evaluación microbiológica por siembra en placa y dilución en placa con agar malta al 1,25%. En todos los casos se obtuvieron micelios.Por último se determinó la actividad de enzimas lacasa  y peroxidasa. La actividad lacasa se determinó por espectrometría usando 0.5mM de ABTS como sustrato en 0,1M de buffer acetato de sodio pH5 y 1 ml de extracto obtenido por extracción salina. La determinación de actividad Mn peroxidasa se realizó con 0.01% de rojo fenol como sustrato en buffer succinato de sodio 0.1M en presencia de 1 ml de extracto enzimático, MnSO4 0.1M y H2O2 0.1M.Las actividad  de éstas enzimas permitió obtener moléculas mas pequeñas producto de la

  1. Planning in deep coal mines prone to spontaneous combustion. Planificacion de explotaciones subterraneas de carbon con propension a fuegos

    Energy Technology Data Exchange (ETDEWEB)

    Leon Marco, P

    1991-03-01

    During the planning process, analysis and assessment of criteria which contribute to spontaneous combustion are used to forecast the level of risk. This information is then used to determine what action should be taken to eliminate or reduce spontaneous combustion. The measures taken involve varying the factors which affect spontaneous combustion in order to make conditions unfavourable to the occurrence of the phenomenon. 1 fig.

  2. Investigating the pros and cons of browns gas and varying EGR on combustion, performance, and emission characteristics of diesel engine.

    Science.gov (United States)

    Thangaraj, Suja; Govindan, Nagarajan

    2018-01-01

    The significance of mileage to the fruitful operation of a trucking organization cannot be downplayed. Fuel is one of the biggest variable expenses in a trucking wander. An attempt is made in this research to improve the combustion efficiency of a diesel engine for better fuel economy by introducing hydroxy gas which is also called browns gas or HHO gas in the suction line, without compromising performance and emission. Brown's gas facilitates the air-fuel mixture to ignite faster and efficient combustion. By considering safety and handling issues in automobiles, HHO gas generation by electrolysis of water in the presence of sodium bicarbonate electrolytes (NaHCO 3 ) and usage was explored in this research work over compressed pure hydrogen, due to generation and capacity of immaculate hydrogen as of now confines the application in diesel engine operation. Brown's gas was utilized as a supplementary fuel in a single-cylinder, four-stroke compression ignition (CI) engine. Experiments were carried out on a constant speed engine at 1500 rpm, result shows at constant HHO flow rate of 0.73 liter per minute (LPM), brake specific fuel consumption (BSFC) decreases by 7% at idle load to 16% at full load, and increases brake thermal efficiency (BTE) by 8.9% at minimum load to 19.7% at full load. In the dual fuel (diesel +HHO) operation, CO emissions decreases by 19.4, 64.3, and 34.6% at 25, 50, and 75% load, respectively, and unburned hydrocarbon (UHC) emissions decreased by 11.3% at minimum load to 33.5% at maximum load at the expense of NO x emission increases by 1.79% at 75% load and 1.76% at full load than neat diesel operation. The negative impact of an increase in NO x is reduced by adding EGR. It was evidenced in this experimental work that the use of Brown's gas with EGR in the dual fuel mode in a diesel engine improves the fuel efficiency, performance, and reduces the exhaust emissions.

  3. Desempeño y emisiones de un motor de combustión interna con combustible dual Diesel – Gas natural ;Performance and emissions study of an internal combustion engine with dual fuel diesel - natural gas

    Directory of Open Access Journals (Sweden)

    Juan Miguel Mantilla González

    2015-04-01

    Full Text Available Muchos de los problemas reportados para los sistemas duales diesel- gas natural ocurren por mala dosificación del gas. Por esta razón se adaptó un sistema de alimentación dual con inyección electrónica de gas natural a un motor de combustión interna encendido por compresión. Se plantea un diseño experimental controlando el dosado de gas natural.Como resultado se obtiene un análisis comparativo entre los valoresde desempeño y emisiones desde la operación Diesel y Diesel-Gas natural. A partir de este análisis es posible observar que el desempeño del motor no se ve afectado por la operación del motor bajo el esquema Dual Diesel-GN, es decir que el motor funcionando bajo modo dual puede sostener las cargas solicitadas al motor. También se observa que la eficiencia volumétrica mejora bajo todas las condiciones de operación dual y las emisiones son mejores sólo cuando el motor trabaja a altas cargas. Many of the problems reported for dual diesel-natural gas systems occur due to poor gas dosage. For this reason a natural gas electronic injection feeding system was adapted to a compression ignitios internal combustion engine. An experimental design controlling the natural gas dosage is considered. As a result a comparative analysis between performance and emissions from the Diesel-and diesel-Natural Gas operation is obtained. From this analysis it is possible to see that engine performance is not affected by operation of the engine under the dual mode, i.e. the motor running under dual mode can support the loads applied to the engine. It is also observed that the volumetric efficiency improves under all conditions of operation and emissions from the dual mode of operation are better only when working at high engine loads.

  4. Hypocholesterolemic impact of newly isolated sophorolipids produced by microbial conversion of safflower oil cake in rats fed high-fat and cholesterol diet; Efecto hipocolesterolémico de soforolípidos recién aislados producidos por la conversión microbiana de la torta de aceite de cártamo en ratas alimentadas con una dieta rica en grasas y colesterol

    Energy Technology Data Exchange (ETDEWEB)

    Nooman, M.U.; Mahmoud, M.H.; Al-kashef, A.S.; Rashad, M. M.

    2017-07-01

    The present study aims to produce low cost sophorolipids, and to evaluate their potential hypocholesterolemic impact. Sophorolipids were produced by Candida bombicola grown on safflower oil cake, extracted by methanol followed by ethyl acetate with a yield of 24.4 and 48.3 g·100 g−1 mixed substrate, respectively. Their structure was confirmed by FTIR and 1H NMR and proven to be safe when subjected to an acute toxicity test. A biological experiment was done on 42 male albino rats classified into six groups for 4 weeks following an induction period for hypercholesterolemia of 8 weeks. The two extracts and their mixture were examined for their hypocholesterolemic effect compared to rosuvastatin. The results revealed a reduction in total cholesterol, low density lipoprotein cholesterol, atherogenic index, liver transaminases’ activity and malondialdehyde. They also revealed an elevation in high density lipoprotein cholesterol and antioxidant enzymes which was more efficient than rosuvastatin. Histopathological examination confirmed these results. In conclusion, the newly isolated sophorolipids are powerful hypocholesterolemic compounds which are even more efficient and safer than rosuvastatin. [Spanish] El presente estudio tiene como objetivo producir soforolípidos de bajo costo, evaluando su potencial impacto hipocolesterolémico. Los soforolípidos fueron producidos por Candida bombicola cultivada en torta de aceite de cártamo, extraída con metanol seguido de acetato de etilo con un rendimiento de 24,4 y 48,3 g·100 g−1 de sustrato mixto, respectivamente. Su estructura fue confirmada por FTIR y 1H RMN y demostró ser segura cuando se sometió a prueba de toxicidad aguda. Un experimento biológico se realizó con 42 ratones albinos machos clasificados en seis grupos, durante 4 semanas, después de un período de inducción al hipercolesterolemia de 8 semanas. Se examinaron los dos extractos y su mezcla para determinar su efecto hipocolesterolémico en

  5. Tecnología de fabricación de arrabio con la inyección de combustibles y otros materiales por toberas en el horno alto. I Parte. Características de los combustibles auxiliares y su influencia en el proceso del horno alto

    Directory of Open Access Journals (Sweden)

    García, L.

    1998-02-01

    Full Text Available The injection of fuels by tuyeres in the blast furnace is a used practice in most furnaces with the principal aim to reduce the coke consumption by ton of pig iron produced. The nature of these fuels is very diverse and depends on the resources of each country and of the fuel price. At this moment the coal injection (pulverized and granular is the most extended practice, and the number of furnaces with facilities for coal injection increases continuously.

    La inyección de combustibles por toberas en el horno alto es una práctica utilizada en la mayoría de los hornos con el objetivo principal de reducir el consumo de coque por tonelada de arrabio fabricado. La naturaleza de estos combustibles es muy diversa y es función de los recursos de cada país y del precio del combustible. En la actualidad, la práctica más extendida es la inyección de carbón (pulverizado y granulado y cada vez es mayor el número de hornos con instalaciones para la inyección de carbón.

  6. Nixtamalización de cinco variedades de maíz con diferente dureza de grano: impacto en consumo de combustible y cambios fisicoquímicos

    OpenAIRE

    Roque-Maciel, Laura; Arámbula-Villa, Gerónimo; López-Espíndola, Mirna; Ortiz-Laurel, Hipólito; Carballo-Carballo, Aquiles; Herrera-Corredor, J. Andrés

    2016-01-01

    Resumen La nixtamalización causa en el grano de maíz cambios físicos, químicos y reológicos que afectan la calidad de la masa y la tortilla. La nixtamalización tradicional de maíz, realizada principalmente en contenedores abiertos, presenta una muy baja utilización de la energía requerida para este proceso, porque puede usar hasta 70 % más del combustible necesario. La correcta selección de los maíces para nixtamalizar contribuye en la calidad de las tortillas y el ahorro de combustible. El o...

  7. Predicción y análisis de emisiones de mezclas combustibles diésel/ biodiésel modificadas con nanopartículas de alúmina y ácido oleico

    Directory of Open Access Journals (Sweden)

    Andrés Peñaloza

    2017-06-01

    Full Text Available El software Diésel-RK fue utilizado para evaluar el efecto del uso de un aditivo basado en nanopartículas de alúmina y ácido oleico para la reducción de emisiones de gases contaminantes en mezclas diésel/biodiésel. Para esto, se estimaron las propiedades físico-químicas de las mezclas combustibles con ayuda de correlaciones para dispersiones coloidales y reglas de mezclado, fijando concentraciones de 10 y 20ppm del aditivo. Los resultados obtenidos mostraron reducciones del 11% y 25% en emisiones de SO2 y material particulado, respectivamente; mientras que las emisiones de CO2 no mostraron mejoras significativas, así como tampoco se presentaron mejoras en el consumo específico de combustible, los cuales permanecieron por debajo del 1,0%. En cuanto a las emisiones de NO2, se observó un incremento desde 2,1g/kWh a 3,1g/kWh con la adición de las diversas concentraciones de nanoaditivo; de esta forma se evidenciaron mejoras en la disminución en el retraso de los tiempos de ignición, lo cual es apropiado para el adecuado funcionamiento de los motores.

  8. Caracterización experimental mediante técnicas ópticas de sprays en combustión con mezclas de combustibles gasolina y diesel

    OpenAIRE

    ESCOBEDO CARBONELL, PABLO

    2017-01-01

    Sprays injected into an atmosphere with thermodynamic conditions similar to those occuring inside the cylinder of an internal combustion engine have been characterized motor of ignition for the compression for the automotive is carried out. As fuel, commercial gasoline and diesel blends are used in different proportions, given the potential mixtures have for producing efficient fuels in compression ignition engines, with pollutant emissions lower than those achieved in current diesel engines....

  9. Feasibility of implementation of an autonomous hybrid system for PEM fuel cells to electrify localities in rural Cuba; Factibilidad de implementacion de un sistema hibrido autonomo con celda de combustible PEM para electrificar localidades rurales en Cuba

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Torres, Yamir [Centro de Estudios de Tecnologias Energeticas Renovables (CETER), Ciudad de la Habana (Cuba)] e-mail: yamir@ceter.cujae.edu.cu

    2009-09-15

    The use of PEM fuel cells to produce electric energy in autonomous systems is closely linked with the production and storage of hydrogen. Eventually joined with sources of renewable energy, this creates an ecologically clean and sustainable system. In several developing countries, localities exist that do not have electricity but have significant unexploited renewable energy power, where an autonomous hybrid system can be designed to electrify these population centers. This work presents a hybrid electricity scheme with a PEM fuel cell to produce hydrogen and electricity in order to electrify rural zones far from the national power grid in Cuba. The electric demand of the zone and available energy power was calculated using the informatics modeling and simulation programs HOMER, PVSYST and Matlab 1,2,3. Variability in wind and photovoltage power was determined based on daylight hours and seasonal periods throughout the year as well as their effect on the production of hydrogen and electricity. It was shown that the energy demand is met even for the most adverse scenarios. This work offers a detailed description of the behavior of the system and evidence of no effect on the environment, enabling the electrification and wellbeing of residents of the locality. [Spanish] El uso de celdas de combustible PEM para la produccion de energia electrica en sistemas autonomos esta estrechamente ligado a la produccion y almacenamiento de hidrogeno. Esto eventualmente unido a las fuentes renovables de energia forma un sistema ecologicamente limpio y sustentable. En varios paises subdesarrollados existen localidades que no cuentan con electricidad y que tienen importantes potenciales energeticos renovables no explotados actualmente en los cuales se puede disenar un sistema hibrido autonomo para electrificar estas poblaciones. En este trabajo se presenta el esquema de un sistema hibrido autonomo con celda de combustible PEM, para la produccion de hidrogeno y electricidad encaminado

  10. Preparation of combustible material from high sulphur coal by means of pyrolysis: magnetic separation; Obtencion de combustibles limpios a partir de carbones con altos contenidos en azure mediante procesos de pirolisis: separacion magnetica

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-11-01

    Basic studies on coal desulphurization by pyrolysis have been carried out with a series of low rank coals with high total sulphur contents and differences in the distribution of sulphur forms. The evolved sulphur compounds were studied by sulphide selective electrode H{sub 2}S and Fourier transform infrared (FTIR) spectroscopy. The mechanisms affecting the sulphur removal during pyrolysis have been studied by scanning electron microscopy coupled with energy dispersive X-ray (SEM-EDX), X-ray diffraction (XRD) and photoelectronic spectroscopy (XPS). A sample coal of 11 Tm, representative of the Teruel basins was processed at pilot scale in a rotary kiln (coal HR). A series of pyrolysis runs simulating the experimental conditions of the rotary kiln were also carried out in laboratory scale. The magnetic behaviour of the chars from the rotary kiln and from the lab-scale pyrolysis was tested. The efficiency of the desulphurization, including pyrolysis and magnetic separation, was calculated. Chars from rotary kiln were tested by thermogravimetric analysis, air reactivity and carbon efficiency combustion in fluidized bed.

  11. Improvement of the performance of a new type of single chamber microbial fuel cell compared to a conventional cell; Mejora del desempeno de un nuevo tipo de celda de combustible microbiana de una camara comparado con una celda convencional

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez Larios, A.L.; Vazquez-Huerta, G.; Esparza-Garcia, F.; Solorza-Feria, O.; Poggi Varaldo, H.M. [Centro de Investigacion y de Estudios Avanzados del IPN, Mexico D.F. (Mexico)]. E-mail: hectorpoggi2001@gmail.com; linevazquez@yahoo.com.mx

    2009-09-15

    The objective of this work was to design, build and operate a new type of microbial fuel cell (MFC-A) and evaluate the architectural changes in the production of electricity. The results were compared with those of a standard fuel cell (MFC-B). The MFC-A consisted of a horizontal acrylate cylinder with two systems of sandwiched electrodes (each with a anode proton exchange membrane-cathode) separated by 78 mm. The MFC-B consisted of an anode and a cathode each in the opposite faces of the cell. The internal resistance of the cells were determined with polarization curves. The cells were operated in batch during 50 h at 30 degrees Celsius obtained with 38 mW/m{sup 2} and 5 mW/m{sup 2} for MFC-A and MFC-B, respectively. The changes in the architecture of the cell and design of the electrodes occurred at a power density 8 times greater, associated with the decrease in internal resistance of 1200 and 3900 {Omega} for MFC-A and MFC-B, respectively. The change in architecture (double electrode in the same volume for MFC-A) enabled obtaining a 13 times greater potential per unit volume, with 922 mW/m{sup 3} in the new MFC-A cell versus 69 mW/m{sup 3} in MFC-B. [Spanish] El objetivo de este trabajo fue disenar, construir y operar una celda de combustible microbiana de nuevo tipo (CCM-A), y evaluar los cambios de arquitectura en la produccion de electricidad. Los resultados fueron comparados con los de una celda de combustible estandar (CCM-B). La CCM-A consistio de un cilindro horizontal de acrilato, con dos sistemas de electrodos emparedados (cada uno con catodo/membrana de intercambio protonico/anodo) separados por 78 mm. La CCM-B consistio de un anodo y un catodo cada uno en las caras opuestas de la celda. Las Ri de las celdas fueron determinadas por curva de polarizacion. Las celdas fueron operadas en lote durante 50 h, a 30 grados centigrados, y fueron inoculadas con un inoculo sulfato reductor (In-SR) y cargadas con un extracto modelo similar al perfil de metabolitos

  12. Desenvolvimento larval de Chrysoperla externa alimentada com Aphis gossypii provenientes de três cultivares de algodoeiro

    Directory of Open Access Journals (Sweden)

    Eunice Cláudia Schlick-Souza

    2011-10-01

    Full Text Available O objetivo deste trabalho foi avaliar os aspectos biológicos de Chrysoperla externa alimentadas com Aphis gossypii provenientes de três cultivares de algodoeiro (FMT 701, Acala 90 e Delta Opal. O experimento foi conduzido no Laboratório de Fitossanidade da Universidade Estadual de Mato Grosso do Sul (UEMS, Unidade de Cassilândia (MS. Os adultos de C. externa foram mantidos em gaiolas de PVC, em sala climatizada. As larvas do predador foram individualizadas em placas de Petri e alimentadas diariamente com pulgões advindos das diferentes cultivares. Larvas que se alimentaram de indíviduos da cultivar FMT 701 apresentaram a viabilidade menor do que as que alimentaram dos afídeos criados nas cultivares Delta Opal e Acala 90. Observou-se redução do consumo diário nas larvas de terceiro ínstar que se alimentaram dos pulgões advindos da cultivar Acala 90. Consequentemente, larvas supridas com pulgões criados nas cultivares Delta Opal e Acala 90, tiveram menor peso, 3,60 e 3,90 mg respectivamente, diferindo significativamente da FMT 701. De modo geral, é possível a utilização de C. externa no controle de A. gossypii nas cultivares estudadas.

  13. Estabilidad oxidativa de huevos enriquecidos con ácidos grasos poliinsaturados omega 3, frente a antioxidantes naturales

    OpenAIRE

    Bernal Gómez, María Elena; Mendonça-Junior, Cássio Xavier de; Mancini-Filho, Jorge

    2003-01-01

    Fueron alimentadas 192 gallinas ponedoras de 22 semanas de edad, de linaje comercial Babcock, durante 30 días con dietas de 0 (cero) y 12,7% de semilla de linaza molida que corresponde a 0 y 5% de aceite de linaza, respectivamente. Fueron definidos 8 tratamientos: 4 grupos con 12,7% de semilla de linaza (control/sin antioxidante; BHA+BHT, 100+100 ppm; orégano, 200 ppm; romero, 200 ppm) y 4 grupos sin semilla de linaza, pero utilizando los mismos antioxidantes. Este estudio fue realizado con e...

  14. Lipidosis hepática asociada con malnutrición y preñez en dos perras

    OpenAIRE

    Giordano, Andrea; Arias, Daniel Osvaldo; Araus, S.; Cohen, M.; Gobello, Cristina

    2004-01-01

    En algunos países latinoamericanos se observó que la ascites ocurre en diferentes momentos post parto en perras alimentadas con dietas hipoproteicas. El objetivo de este articulo fue describir 2 casos de perras con ascitis asociada a lipidosis hepática desarrollada después del parto. Las muestras de sangre evidenciaron anormarmalidades compatibles con enfermedad hepática. La paracentesis abdominal reveló un trasudado aséptico y la ultrasonografía hiperecogenicidad hepática. Se arribó al diagn...

  15. 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-...

  16. Combustion physics

    Science.gov (United States)

    Jones, A. R.

    1985-11-01

    Over 90% of our energy comes from combustion. By the year 2000 the figure will still be 80%, even allowing for nuclear and alternative energy sources. There are many familiar examples of combustion use, both domestic and industrial. These range from the Bunsen burner to large flares, from small combustion chambers, such as those in car engines, to industrial furnaces for steel manufacture or the generation of megawatts of electricity. There are also fires and explosions. The bountiful energy release from combustion, however, brings its problems, prominent among which are diminishing fuel resources and pollution. Combustion science is directed towards finding ways of improving efficiency and reducing pollution. One may ask, since combustion is a chemical reaction, why physics is involved: the answer is in three parts. First, chemicals cannot react unless they come together. In most flames the fuel and air are initially separate. The chemical reaction in the gas phase is very fast compared with the rate of mixing. Thus, once the fuel and air are mixed the reaction can be considered to occur instantaneously and fluid mechanics limits the rate of burning. Secondly, thermodynamics and heat transfer determine the thermal properties of the combustion products. Heat transfer also plays a role by preheating the reactants and is essential to extracting useful work. Fluid mechanics is relevant if work is to be performed directly, as in a turbine. Finally, physical methods, including electric probes, acoustics, optics, spectroscopy and pyrometry, are used to examine flames. The article is concerned mainly with how physics is used to improve the efficiency of combustion.

  17. Construction of an electrolytic photocell fuel cell system used to energize a cellular telephone; Construccion de un sistema fotocelda-electrolizador-celda de combustible, utilizado para energizar un telefono celular

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes Quezada, Eduardo; Rodriguez-Castellanos, A.; Solorza Feria, O. [CINVESTAV-IPN, Mexico, D.F. (Mexico)]. E-mail: edfq_1986@hotmail.com

    2009-09-15

    de carbono que es liberado a la atmosfera, ademas de contribuir en gran parte al calentamiento global del planeta. Una alternativa para la generacion de energia electrica es la utilizacion de celdas de combustible de membrana polimerica (PEMFC) las cuales promoveran la utilizacion de combustibles alternos como el hidrogeno. En este trabajo se presenta la puesta en operacion de un sistema constituido por una celda fotovoltaica un electrolizador y una PEMFC. La celda fotovoltaica trasforma la energia solar en electrica con la que se electroliza el agua proporcionando hidrogeno (combustible) y oxigeno (comburente). Se diseno y construyo un electrolizador el cual fue caracterizado mediante ensayos de polarizacion. Los gases obtenidos del electrolizador son alimentados a una celda de combustible disenada y construida en el laboratorio. Para darle aplicacion a este trabajo la energia producida en la celda de combustible es alimentada a un dispositivo de baja potencia como lo es la carga electrica de un telefono movil. La integracion de dispositivos electroquimicos revolucionaran por completo las fuentes de energia que hoy en dia estan basadas en los derivados del petroleo. Estos sistemas integrados son eficientes para la produccion de energia electrica sin emisiones de gases contaminantes.

  18. 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.

  19. Desempenho de vacas em lactação alimentadas com dietas contendo torta de macaúba

    Directory of Open Access Journals (Sweden)

    R.A. Azevedo

    2014-02-01

    Full Text Available Avaliaram-se o consumo de nutrientes e a produção e composição do leite de vacas da raça Holandesa alimentadas com dietas contendo diferentes quantidades de inclusão de torta de macaúba. Oito animais foram distribuídos em dois quadrados latinos 4x4, sendo quatro tratamentos, 0, 100, 200 e 300g kg-1 de TM na matéria seca da dieta, e quatro períodos experimentais de 21 dias, 14 de adaptação e sete de avaliações. A adição de quantidades crescentes de torta de macaúba à dieta alterou o consumo de matéria seca, matéria orgânica, proteína bruta, extrato etéreo, fibra em detergente neutro, carboidratos não fibrosos, produção e os teores de lactose, extrato seco desengordurado e sólidos totais do leite, bem como a eficiência alimentar e a digestibilidade da matéria seca. Por outro lado, não foi verificada diferença nos teores de gordura do leite. A adição da TM em até 300g kg-1 da dieta comprometeu o consumo e o desempenho produtivo dos animais.

  20. Estabilidad oxidativa de huevos enriquecidos con ácidos grasos poliinsaturados omega 3, frente a antioxidantes naturales Estabilidade oxidativa de ovos enriquecidos com ácidos graxos poliinsaturados ômega 3, frente a antioxidantes naturais

    OpenAIRE

    María Elena Bernal Gómez; Cássio Xavier de Mendonça-Junior; Jorge Mancini-Filho

    2003-01-01

    Fueron alimentadas 192 gallinas ponedoras de 22 semanas de edad, de linaje comercial Babcock, durante 30 días con dietas de 0 (cero) y 12,7% de semilla de linaza molida que corresponde a 0 y 5% de aceite de linaza, respectivamente. Fueron definidos 8 tratamientos: 4 grupos con 12,7% de semilla de linaza (control/sin antioxidante; BHA+BHT, 100+100 ppm; orégano, 200 ppm; romero, 200 ppm) y 4 grupos sin semilla de linaza, pero utilizando los mismos antioxidantes. Este estudio fue realizado con e...

  1. 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...

  2. 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).

  3. Perfil hematológico de éguas Quarto de Milha alimentadas com feno ou haylage de Tifton-85 ( Cynodon spp.)

    OpenAIRE

    Guimarães, T.C.; Rezende, A.S.C.; Costa, M.L.L.; Ferreira, M.G.; Soto-Blanco, B.; Melo, M.M.

    2016-01-01

    RESUMO O capim Tifton-85 (Cynodon spp.) vem sendo utilizado na alimentação de equinos na forma de pré-secado (haylage) e feno, todavia não existem estudos conclusivos a respeito da influência da haylage sobre o estado de saúde dessa espécie. Portanto, esta pesquisa objetivou avaliar o perfil sanguíneo como indicador de higidez de éguas Quarto de Milha alimentadas com haylage e feno de Tifton-85. A gramínea utilizada foi cortada com 30 dias de crescimento. Para produção da haylage, a planta co...

  4. Fabrication and Testing of Prototype APM-Clad UO{sub 2} Fuel Elements; Fabrication et essai de prototypes de cartouches de combustible en bioxyde d'uranium gaine d'aluminium (APM); Izgotovlenie i ispytanie prototipa toplivnykh ehlementov na osnove UO{sub 2} s obolochkoj iz alyuminiya metodom poroshkovoj metallurgii; Elaboracion y ensayo de elementos combustibles prototipo de UO{sub 2} con revestimiento de aluminio sinterizado

    Energy Technology Data Exchange (ETDEWEB)

    Ballif, III, J. L.; Friske, W. H.; Gordon, R. B. [Atomics International, Canoga Park, California (United States)

    1963-11-15

    disposees selon un pas helicoidal de 45 ou 90{sup o}/30 cm. L'obturation des gaines des barreaux etait assuree par des bouchons en aluminium plaque argent, lies par alliage eutectique aux tubes APM. Les cartouches etaient equipees d'instruments permettant de: 1. Mesurer la temperature du fluide de refroidissement et la temperature superficielle des gaines; 2. Deceler les defectuosites des barreaux de combustible; 3. Modifier la vitesse du fluide de refroidissement (on pourrait ainsi obtenir des temperatures maximums de l'ordre de 455{sup o}C a la surface de la gaine); 4. Mesurer la vitesse du fluide de refroidissement; 5. Mesurer le degagement des produits de fission gazeux. Ces cartouches ont ete installees dans le reacteur OMRE pour atteindre un taux de combustion de l'ordre de 25000 a 30000 MWj/tU. Au 1er avril 1963 le taux atteint etait de 7700 a 12000 MWj/tU. Deux des cartouches ont ete retirees du reacteur a la suite de difficultes suscitees par leurs instruments de mesure. Les trois autres cartouches ont ete maintenues dans le reacteur. A ce jour, les resusltats de ces travaux experimentaux donnent a penser que le combustible APM-UO{sub 2} permettra d'atteindre les objectifs du programme de POPR. (author) [Spanish] En ejecucion del programa relativo al reactor de potencia prototipo de moderador organico de 50 MW(e) (POPR), se han llevado a cabo amplios trabajos de investigacion sobre productos elaborados por pulvimetalurgia de aluminio (PMA), con el fin de utilizarlos como revestimiento para el combustible de UO{sub 2}. Como parte de estos trabajos, se ha investigado la aptidud de los metodos de union eutectica, de soldadura a tope por chispas y de soldadura por compresion en frio ''Koldweld'', para realizar los cierres de los extremos del revestimiento de los elementos combustibles. Se ha estudiado la compresion vibratoria como procedimiento para rellenar de UO{sub 2} los tubos de PMA. Se han realizado ensayos fuera de reactor para reunir datos sobre la

  5. High Combustion Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — At NETL's High-Pressure Combustion Research Facility in Morgantown, WV, researchers can investigate new high-pressure, high-temperature hydrogen turbine combustion...

  6. 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...

  7. 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).

  8. 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

  9. Rotary combustion device

    NARCIS (Netherlands)

    2008-01-01

    Rotary combustion device (1) with rotary combustion chamber (4). Specific measures are taken to provide ignition of a combustible mixture. It is proposed that a hollow tube be provided coaxially with the axis of rotation (6), so that a small part of the mixture is guided into the combustion chamber.

  10. Adaptación de un motor de combustión interna alternativo de gasolina para su funcionamiento con hidrógeno como combustible. Aplicaciones energética y de automoción

    OpenAIRE

    Sáinz Casas, David

    2016-01-01

    En esta tesis doctoral se presentan los trabajos de investigación realizados recientemente en la Universidad Pública de Navarra sobre la conversión de motores de gasolina para su funcionamiento con hidrógeno, así como el desarrollo de aplicaciones demostrativas prácticas empleando estos motores. Esta línea de investigación es continuación de la producción electrolítica de hidrógeno con energía eólica [15-17]. El objetivo principal de esta tesis es la demostración práctica de la viabilidad de ...

  11. Qualidade da carne de fêmeas suínas alimentadas com diferentes concentrações de ractopamina na dieta

    Directory of Open Access Journals (Sweden)

    P.H. Watanabe

    2012-10-01

    Full Text Available Analisaram-se as qualidades física, química e sensorial, bem como o perfil de ácidos graxos da carne de fêmeas suínas alimentadas com dietas com concentrações crescentes de ractopamina. Foram utilizadas 468 fêmeas, com peso inicial de 84,77±7,20kg, alojadas em 36 baias e alimentadas com dietas contendo 0, 5, 10 ou 15mg de ractopamina/kg. Após o período de 28 dias, dois animais de cada baia, depois de passarem por 15 horas de jejum sólido, foram abatidos. Uma amostra do músculo Longissimus da meia carcaça direita foi colhida para se avaliar as características de qualidade da carne. Não houve efeito (P>0,05 da adição de ractopamina às dietas sobre o pH, capacidade de retenção de água, força de cisalhamento, cor e oxidação lipídica da carne. Observou-se efeito quadrático (P0,05 na análise sensorial da carne. Também não foi observado efeito (P>0,05 sobre a composição em ácidos graxos e sobre a relação entre ácidos graxos saturados:insaturados. A adição de até 15mg de ractopamina/kg de dieta não altera as características físicas, sensoriais e o perfil de ácidos graxos da carne de fêmeas suínas abatidas com 110kg de peso.

  12. 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

  13. Reduced NOX combustion method

    International Nuclear Information System (INIS)

    Delano, M.A.

    1991-01-01

    This patent describes a method for combusting fuel and oxidant to achieve reduced formation of nitrogen oxides. It comprises: It comprises: heating a combustion zone to a temperature at least equal to 1500 degrees F.; injecting into the heated combustion zone a stream of oxidant at a velocity within the range of from 200 to 1070 feet per second; injecting into the combustion zone, spaced from the oxidant stream, a fuel stream at a velocity such that the ratio of oxidant stream velocity to fuel stream velocity does not exceed 20; aspirating combustion gases into the oxidant stream and thereafter intermixing the aspirated oxidant stream and fuel stream to form a combustible mixture; combusting the combustible mixture to produce combustion gases for the aspiration; and maintaining the fuel stream substantially free from contact with oxidant prior to the intermixture with aspirated oxidant

  14. Computation and Analysis of EGR Mixing in Internal Combustion Engine Manifolds

    OpenAIRE

    Sakowitz, Alexander

    2013-01-01

    This thesis deals with turbulent mixing processes occurring in internal combustion engines, when applying exhaust gas recirculation (EGR). EGR is a very efficient way to reduce emissions of nitrogen oxides (NOx) in internal combustion engines. Exhaust gases are recirculated and mixed with the fresh intake air, reducing the oxygen con- centration of the combustion gas and thus the peak combustion temperatures. This temperature decrease results in a reduction of NOx emissions. When applying EGR...

  15. Non-Destructive Testing Methods Applied to Multi-Finned SAP Tubing for Nuclear-Fuel Elements; Essais Non Destructifs de Gaines a Ailettes, en Poudre d'Aluminium Frittee, pour Elements Combustibles; Nedestruktivnye metody ispytaniya rebristykh trub iz spechennogo alyuminikiog'o poroshka dlya yadernykh toplivnykh ehlementov; Metodos de Ensayo No Destructivo Aplicados a Tubos de SAP con Aletas Multiples Destinados a Elementos Combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Lund, S. A. [Danish Central Welding Institution, Copenhagen (Denmark); Knudsen, P. [Danish Atomic Energy Commission, Research Establishment, Risoe (Denmark)

    1965-09-15

    Energia Atomica de Dinamarca ha emprendido el estudio de un reactor de potencia con refrigerante organico y moderador de agua pesada. Los correspondientes elementos combustibles consisten en haces de 19 barras formadas por pastillas de dioxido de uranio sinterizado, encerradas en tubos de producto de aluminio sinterizado (SAP), de 2 m de longitud, provistos de aletas helicoidales. Para obtener condiciones optimas de transmision de calor y mantener la integridad del elemento combustible durante el funcionamiento del reactor, es necesario contar con tubos de muy alta calidad. Se citan dos ejemplos que ponen de manifiesto las estrechas tolerancias dimensionales adoptadas. Para asegurar una calidad adecuada de los tubos, se establecio un control de calidad muy estricto, basado en gran medida en la aplicacion de metodos no destructivos. Se describen en esta memoria las tecnicas desarrolladas para medir el espesor de pared y los diametros, y para descubrir defectos. La compleja seccion transversal, con 24 aletas, impide aplicar metodos ultrasonicos o de comentes de Foucault para medir el espesor de la pared. Por consiguiente, se desarrollo un calibre registrador de rayos beta, cuyo funcionamiento se basa en la atenuacion sufrida por la radiacion beta proveniente de una fuente de {sup 90}Sr colocada en el interior del tubo. Para el registro continuo del espesor de la pared del tubo con seccion transversal mas simple, de 12 aletas, se utiliza un metodo ultrasonico de resonancia por inmersion. Los diametros interno y externo (entre puntos de aletas) se registran de manera continua mediante calibres neumaticos rapidos. Las fallas se detectan mediante la tecnica de eco de impulsos ultrasonicos, y examinando los tubos con corrientes de Foucault. El metodo ultrasonico permite descubrir facilmente las fisuras transversales, pero hasta ahora ha sido imposible utilizarlo para la deteccion de defectos longitudinales. Por consiguiente, ademas del ensayo ultrasonico, se aplica el examen con

  16. Model of the containment building of Almaraz NPP and the system of recombiners PARs, with the GOTHIC code, for the study of the diffusion of combustible gases; Modelo del edificio de contencion de C.N. Almaraz y del sistema de recombinadores PARs, con el codigo GOTHIC, para el estudio de la difusion de gases combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Gonzalez, M.; Huelamo, E.; Mazrtinez, M.; Perez, J. R.

    2014-07-01

    This paper presents the analysis of distribution of gases within the containment building carried out a simulation model with the code Thermo hydraulic GOTHIC, which has been evaluated based on passive autocatalytic recombiners gas control system. The model considers scenarios of severe accident with specific conditions that produce the most hydrogen generation rates. Intended to verify the effectiveness of the control system of gas expected to be installed in the Almaraz Nuclear power plant so that the number and location of recombiners equipment meets its function of preventing the formation of explosive atmospheres which impairs the integrity of the containment, reducing and limiting the concentration of combustible gases during the postulated accident. (Author)

  17. 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...

  18. Alcohol combustion chemistry

    KAUST Repository

    Sarathy, Mani; Oß wald, Patrick; Hansen, Nils; Kohse-Hö inghaus, Katharina

    2014-01-01

    . 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

  19. Maximal combustion temperature estimation

    International Nuclear Information System (INIS)

    Golodova, E; Shchepakina, E

    2006-01-01

    This work is concerned with the phenomenon of delayed loss of stability and the estimation of the maximal temperature of safe combustion. Using the qualitative theory of singular perturbations and canard techniques we determine the maximal temperature on the trajectories located in the transition region between the slow combustion regime and the explosive one. This approach is used to estimate the maximal temperature of safe combustion in multi-phase combustion models

  20. Tecnología de fabricación de arrabio con inyección de combustibles y otros materiales por toberas en el horno alto. II parte. Inyección de carbón pulverizado (ICP

    Directory of Open Access Journals (Sweden)

    García, L.

    1998-06-01

    Full Text Available The technology of ironmaking with coal injection by tuyeres in the blast furnace is described. The influence of the main coal constituents in the furnace operation is analyzed. Information about the countries that employ this technology is given.

    Se describe la tecnología de fabricación de arrabio con inyección de carbón por toberas en el horno alto. Se analiza y comenta la influencia de los principales constituyentes del carbón en la operación del horno. Se ofrece información sobre los países que emplean esta tecnología.

  1. 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.

  2. Uncertainties in hydrogen combustion

    International Nuclear Information System (INIS)

    Stamps, D.W.; Wong, C.C.; Nelson, L.S.

    1988-01-01

    Three important areas of hydrogen combustion with uncertainties are identified: high-temperature combustion, flame acceleration and deflagration-to-detonation transition, and aerosol resuspension during hydrogen combustion. The uncertainties associated with high-temperature combustion may affect at least three different accident scenarios: the in-cavity oxidation of combustible gases produced by core-concrete interactions, the direct containment heating hydrogen problem, and the possibility of local detonations. How these uncertainties may affect the sequence of various accident scenarios is discussed and recommendations are made to reduce these uncertainties. 40 references

  3. Comportamento ingestivo de novilhas leiteiras alimentadas com dietas à base de Cana-de-açúcar Ingestive behavior of dairy heifers fed sugar cane based diets

    Directory of Open Access Journals (Sweden)

    Lídia Ferreira Miranda

    1999-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o comportamento ingestivo de novilhas mestiças Holandês x Zebu alimentadas com dietas à base de cana-de-açúcar suplementadas com fontes de nitrogênio não-protéico [NNP] (uréia e cama de frango, em substituição parcial da uréia e, ou, adição de probióticos (sem probiótico, com levedura ou com microbiota ruminal. Vinte e quatro novilhas, com idade e peso médio inicial de 15 meses e 247 kg, respectivamente, foram mantidas em baias individuais e alimentadas à vontade, durante o período experimental de 84 dias. Os animais foram distribuídos em delineamento inteiramente casualisado, em esquema fatorial 2 x 3 (fontes de NNP vs fontes de probiótico, com quatro repetições. O comportamento ingestivo de cada novilha foi determinado visualmente, a cada 28 dias, a intervalos de 10 minutos, durante 24 horas. Não houve diferença no tempo despendido em alimentação, ruminação e mastigação total, em min/dia, das novilhas alimentadas com diferentes fontes de NNP e probióticos. O tempo médio de ruminação, em min/kg de MS e FDN, foi maior para os animais alimentados com uréia. O comportamento ingestivo das novilhas não foi influenciado pelas fontes de nitrogênio ou pela adição de probiótico.The objective of this work was to evaluate the ingestive behavior of crossbred dairy heifers fed sugar-cane based diets, supplemented with non protein nitrogen [NPN] sources (urea or broiler litter, in replacement of urea and, or, probiotics addition (without probiotic, with yeast or with ruminal microbiota. Twenty-four heifers, with age and average initial weight of 15 months and 247 kg, respectively, were maintained in individual stalls and ad libitum fed during the experimental period of 84 days. The animals were allotted to a completely randomized design, in a 2 x 3 factorial arrangement (NPN source vs probiotic source, with four replicates. The ingestive behavior of each heifer was visually

  4. New class of combustion processes

    International Nuclear Information System (INIS)

    Merzhanov, A.G.; Borovinskaya, I.P.

    1975-01-01

    A short review is given of the results of work carried out since 1967 on studying the combustion processes caused by the interaction of chemical elements in the condensed phase and leading to the formation of refractory compounds. New phenomena and processes are described which are revealed when investigating the combustion of the systems of this class, viz solid-phase combustion, fast combustion in the condensed phase, filtering combustion, combustion in liquid nitrogen, spinning combustion, self-oscillating combustion, and repeated combustion. A new direction in employment of combustion processes is discussed, viz. a self-propagating high-temperature synthesis of refractory nitrides, carbides, borides, silicides and other compounds

  5. Application of coal combustion residues to the stabilization/solidification of industrial wastes (IRIS); Desarrollo de un Proceso, a Escala Piloto de Inertizacion de Residuos Industriales con Cenizas Volantes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    Stabilization/solidification (S/S) processes, also called inertization processes, are a group of techniques which employ additives to reduce the mobility of the hazardous components from the waste and make possible for the residue to be accepted for its disposal in a safe way. These processes, mainly applied to wastes that contain heavy metals (such as lead, zinc, cadminum, mercury, copper, nickel, titanium, chromium-III, chromium-VI, arsenic,....) change the waste into a solid-like material in which the metals are trapped (nets and matrix) by physical or chemical links. The IRIS Project, carried out by AICIA through the ECSC Coal Programme with the participation of two industrial partners (Sevillana de Electricidad and EGMASA, a public-owned company for waste treatment), has developed, at pilot scale, a new S/S process for inorganic industrial wastes that uses great quantities of fly ash in the place of other more commonly used and expansive reagents. A pilot plant for 200 kg/h has been designed, built and operated. This facility has allowed to add improvements and scientific foundations to existing S/S technology. It has also allowed to obtain industrial scale parameters for fixed and portable plants. Experiencie have been mainly carried out using fly ash from high quality coals, but types of ash have been tested coming from coals with a greater calcium content, from fluidised bed combustion boilers and from desulphurisation processes, giving very suitable characteristics for their application to S/S processes. The addition of fly ash (up to 30%) in the IRIS process improves the results in comparison with the S/S processes that use only cement, because the final pH obtained (8-11) does not allow amphoteric metallic ions to escape in the leachate. The same as other S/S processes, IRIS can be applied also to wastes that contain certain metals (chromium-VI, arsenic, for example) with specific pre-treatments (redox, for example). The efficiency of the IRIS treatment

  6. 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.

  7. 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.

  8. Welding with the TIG automatic process of the end fittings for the execution of the Embalse nuclear power plant fuel channel rechange; Soldadura con proceso TIG automatico de los accesorios extremos (end fitting) para la ejecucion de un recambio de canal de combustible en el reactor de la Central Nuclear Embalse

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, P O

    1991-12-31

    The present work describes the methodology for the cutting of the existing welding and subsequent welding applied by the TIG process of the coupling composed by the shroud ring and the end fitting ring from one of Embalse nuclear power plant`s fuel channels. The replacement will be previously determined by the SLAR-ETTE mechanism where a displacement operated among the Gartner Spring rings, the pressure tubes are separated from the Calandria tubes. The welding to be carried out has the function of stamping the CO{sub 2} annular gas (thermal insulator) circulating between the pressure tube and the Calandria one during the functioning of the plant. (Author). [Espanol] El presente trabajo describe la metodologia de corte de la soldadura existente y la posterior soldadura aplicada mediante proceso TIG de la junta compuesta por el aro de fuelle y el anillo del `end fitting`, de uno de los canales de combustibles del reactor de la Central Nuclear Embalse. El reemplazo, se determinara previamente mediante el mecanismo de SLAR-ETTE con lo cual se observara el desplazamiento operado entre los anillos garten spring que separan los tubos de presion de los tubos de calandria. La soldadura a efectuar cumple la funcion de sellar el gas anular CO{sub 2} (aislante termico) circulante entre el tubo de presion y el tubo de calandria durante el funcionamiento de la planta. (Autor).

  9. The epithermal critical experiments; Experiences critiques avec des neutrons epitliermiques; Nadteplovye kriticheskie ehksperimenty; Experimentos criticos con neutrones epitermicos

    Energy Technology Data Exchange (ETDEWEB)

    Morewitz, H A; Carpenter, S O [Atomics International, Canoga Park, CA (United States)

    1962-03-15

    rapport entre les quantites de graphite et de combustible. Une experience a l'aide d'un oscillateur a ondes carrees definit les valeurs de la reactivite centrale de quarante petits echantillons de differents materiaux, jusqu'a 10{sup -8} {Delta}k pour chaque ensemble. De plus, on fait osciller des sources artificielles de neutrons, etalonnees entre elles, pour determiner les differentes fonctions neutroniques importantes au centre du montage. On obtient les spectres en procedant a des mesures a l'aide de compteurs a fission comportant des feuilles etalonnees de seuils differents et d'un spectrometre a compteur au {sup 6}Li. Une methode de traitement numerique permettra de grouper toutes les mesures en un fichier autonome de sections efficaces moyennes par spectre. (author) [Spanish] La fase actual del programa del reactor epitermico de tipo avanzado, alimentado con torio, comprende una serie de experimentos integrales sobre fisica de los reactores, cuyo objeto es reunir datos sobre las secciones eficaces neutronicas en el intervalo 1 keV a 10 MeV. Se esta estudiando una serie de nueve conjuntos criticos de varias regiones, con acoplamiento termico-rapido, de forma pseudoesferica, del tipo alveolar de cuerpo dividido. Hasta ahora se han puesto en servicio tres conjuntos de esa indole. La region externa de conexion-desconexio n acciona una region de ensayo interna de forma esferica alimentada con {sup 233}U-Th, cuyo espectro neutronico se degrada progresivament e aumentando la razon grafito-combustible . Un experimento efectuado con un oscilador de onda cuadrada define los valores de la reactividad central de cuarenta pequenas muestras de diferentes materiales, hasta 10{sup -8} {Delta}k; para cada conjunto. Ademas, se hacen oscilar fuentes artificiales de neutrones intercalibradas para determinar las diferentes funciones neutronicas que revisten importancia en el centro del conjunto. Los espectros se obtienen procediendo a mediciones con contadores de fision

  10. Recria e terminação de borregas mestiças em confinamento alimentadas com níveis crescentes de concentrado na dieta

    Directory of Open Access Journals (Sweden)

    Caroline Bertholini Ribeiro

    2016-12-01

    Full Text Available Objetivou-se avaliar dietas com níveis crescentes de concentrado para borregas confinadas e estabelecer a proporção de concentrado ideal para maximizar a utilização dos nutrientes e o desempenho durante as fases de recria e terminação. Foram confinadas 24 borregas alimentadas com feno de capim-Tifton e níveis crescentes de concentrado na dieta (20, 40, 60 e 80% para avaliação individual do consumo de matéria seca (CMS, digestibilidade dos nutrientes das dietas, ganho médio diário (GMD e eficiência alimentar (EA. As borregas foram abatidas com 47 kg. Na fase de recria, o CMS não foi alterado (P>0,05 pela inclusão de concentrado nas dietas (1176 g/dia. Foi observado efeito quadrático dos níveis de concentrado (P0,05. O CDMS e o valor de NDT apresentaram comportamento quadrático (P0,05. Recomenda-se a inclusão de 71,50% de concentrado na dieta de borregas para maximizar o aproveitamento dos nutrientes e o desempenho na fase de recria e 72,3% de concentrado para fase de terminação.

  11. Expressão gênica de adipocinas em ovelhas alimentadas com resíduos da indústria do biodiesel da mamona

    Directory of Open Access Journals (Sweden)

    S.S. Duarte

    2014-08-01

    Full Text Available A expressão de RNAm para leptina, receptor de leptina (obRb, adiponectina, receptor de adiponectina (AdipoR1 e resistina foi avaliada por meio da técnica de PCR em tempo real, em tecidos ovariano, hipofisário, adiposo do omento e da região perirrenal, em ovelhas alimentadas sem farelo de mamona ou com farelo de mamona detoxificada durante 14 meses. O tipo de dieta não afetou os níveis de RNAm para leptina, obRb, adiponectina, AdipoR1 e resistina nos diferentes tecidos avaliados (P>0,05. Nos tecidos ovariano e hipofisário, não foi verificada a expressão da adiponecina e da resistina, respectivamente. Como consequência, pode-se concluir que o farelo de mamona detoxificada pode ser utilizado como fonte proteica na dieta de ovelhas, sem afetar a expressão do gene resistina e dos genes leptina e adiponectina, bem como de seus receptores.

  12. 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.

  13. Flameless Combustion Workshop

    National Research Council Canada - National Science Library

    Gutmark, Ephraim

    2005-01-01

    .... "Flameless Combustion" is characterized by high stability levels with virtually no thermoacoustic instabilities, very low lean stability limits and therefore extremely low NOx production, efficient...

  14. Research Combustion Laboratory (RCL)

    Data.gov (United States)

    Federal Laboratory Consortium — The Research Combustion Laboratory (RCL) develops aerospace propulsion technology by performing tests on propulsion components and materials. Altitudes up to 137,000...

  15. 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.

  16. Combustion Stratification for Naphtha from CI Combustion to PPC

    KAUST Repository

    Vallinayagam, R.; Vedharaj, S.; An, Yanzhao; Dawood, Alaaeldin; Izadi Najafabadi, Mohammad; Somers, Bart; Johansson, Bengt

    2017-01-01

    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

  17. 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

  18. Catalytically enhanced combustion process

    International Nuclear Information System (INIS)

    Rodriguez, C.

    1992-01-01

    This patent describes a fuel having improved combustion efficiency. It comprises a petroleum based liquid hydrocarbon; and a combustion catalyst comprising from about 18 to about 21 weight percent naphthalene, from about 75 to about 80 weight percent toluene, and from about 2.8 to about 3.2 weight percent benzyl alcohol

  19. Fifteenth combustion research conference

    International Nuclear Information System (INIS)

    1993-01-01

    The BES research efforts cover chemical reaction theory, experimental dynamics and spectroscopy, thermodynamics of combustion intermediates, chemical kinetics, reaction mechanisms, combustion diagnostics, and fluid dynamics and chemically reacting flows. 98 papers and abstracts are included. Separate abstracts were prepared for the papers

  20. 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.

  1. Fuels and Combustion

    KAUST Repository

    Johansson, Bengt

    2016-01-01

    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.

  2. 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...

  3. Desarrollo y validación experimental de un modelo computacional de pilas de combustible tipo PEM y su aplicación al análisis de monoceldas

    OpenAIRE

    Iranzo Paricio, Alfredo

    2010-01-01

    La presente tesis doctoral tiene como objetivo fundamental el desarrollo de un modelo computacional para pilas de combustible tipo PEM, que suponga un avance con respecto al estado actual del modelado de pilas de combustible. ... * Desarrollo de un model

  4. Fuel Combustion Laboratory | Transportation Research | NREL

    Science.gov (United States)

    Fuel Combustion Laboratory Fuel Combustion Laboratory NREL's Fuel Combustion Laboratory focuses on designs, using both today's technology and future advanced combustion concepts. This lab supports the combustion chamber platform for fuel ignition kinetics research, was acquired to expand the lab's

  5. 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.

  6. Shale oil combustion

    International Nuclear Information System (INIS)

    Al-dabbas, M.A.

    1992-05-01

    A 'coutant' carbon steel combustion chamber cooled by water jacket was conslructed to burn diesel fuel and mixlure of shale oil and diesel fuels. During experimental work nir fuel ratio was determined, temperaturces were measured using Chromel/ Almel thermocouple, finally the gasous combustion product analysis was carricd out using gas chromatograph technique. The constructed combustion chamber was operating salisfactory for several hours of continous work. According to the measurements it was found that: the flame temperature of a mixture of diesel and shale oil fuels was greater than the flame temperature of diesel fuel. and the sulfer emissious of a mixture of diesel and shale oil fuels was higher than that of diesel fuel. Calculation indicated that the dry gas energy loss was very high and the incomplete combustion energy loss very small. (author). 23 refs., 35 figs

  7. Shale oil combustion

    Energy Technology Data Exchange (ETDEWEB)

    Al-dabbas, M A

    1992-05-01

    A `coutant` carbon steel combustion chamber cooled by water jacket was conslructed to burn diesel fuel and mixlure of shale oil and diesel fuels. During experimental work nir fuel ratio was determined, temperaturces were measured using Chromel/ Almel thermocouple, finally the gasous combustion product analysis was carricd out using gas chromatograph technique. The constructed combustion chamber was operating salisfactory for several hours of continous work. According to the measurements it was found that: the flame temperature of a mixture of diesel and shale oil fuels was greater than the flame temperature of diesel fuel. and the sulfer emissious of a mixture of diesel and shale oil fuels was higher than that of diesel fuel. Calculation indicated that the dry gas energy loss was very high and the incomplete combustion energy loss very small. (author). 23 refs., 35 figs.

  8. Indoor combustion and asthma.

    Science.gov (United States)

    Belanger, Kathleen; Triche, Elizabeth W

    2008-08-01

    Indoor combustion produces both gases (eg, nitrogen dioxide, carbon monoxide) and particulate matter that may affect the development or exacerbation of asthma. Sources in the home include both heating devices (eg, fireplaces, woodstoves, kerosene heaters, flued [ie, vented] or nonflued gas heaters) and gas stoves for cooking. This article highlights the recent literature examining associations between exposure to indoor combustion and asthma development and severity. Since asthma is a chronic condition affecting both children and adults, both age groups are included in this article. Overall, there is some evidence of an association between exposure to indoor combustion and asthma, particularly asthma symptoms in children. Some sources of combustion such as coal stoves have been more consistently associated with these outcomes than other sources such as woodstoves.

  9. 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.

  10. para celdas de combustible de etanol

    Directory of Open Access Journals (Sweden)

    CARLOS MONSALVE GIL

    2008-01-01

    Full Text Available En este trabajo se elaboraron dos membranas nanocompuestas de Nafion®- TiO2 con 2 y 4% del cerámico por el método del “recasting”. El análisis de composición del microscopio de barrido electrónico (SEMEDS mostró una estructura de dos capas, una enriquecida en cerámico y otra con menos cantidad, pero con dispersión uniforme. Se midió la velocidad de permeación de etanol y la absorción de solventes en estas membranas a diferentes temperaturas y concentraciones y los resultados fueron comparados con los obtenidos para la membrana de Nafion® sin modificar. Los resultados experimentales mostraron un incremento de la permeación y de la absorción de solvente con la concentración de etanol y la temperatura. La absorción de agua también mostró un incremento en las membranas compuestas lo cual puede permitir operar a mayores temperaturas y menores humedades relativas y aumentar el desempeño de la celda de combustible.

  11. Iluminación con Energía Solar Fotovoltaica para Autoservicios en Bogotá

    Directory of Open Access Journals (Sweden)

    Wilmar Giovani Santamaría

    2015-07-01

    Full Text Available Este artículo presenta un estudio técnico y económico sobre el uso de energía fotovoltaica para iluminación en dos (2 autoservicios en la ciudad de Bogotá. Se analizan diferentes aspectos a tener en cuenta, como la radiación solar mínima sobre el área considerada y los consumos en iluminación con energía convencional. Se estima que, al realizar el cambio de iluminación de bombillos fluorescentes a bombillos LED y establecer como fuente primaria las baterías previamente alimentadas con energía fotovoltaica, se reduce el consumo de energía eléctrica de manera considerable en iluminación. Con esta hipótesis, se plantean tres opciones de sistemas fotovoltaicos autónomos para cada uno de los autoservicios con todos los elementos necesarios para el mejor funcionamiento, el estudio económico de cada opción y un estimativo del ahorro energético.

  12. Perfil hematológico de éguas Quarto de Milha alimentadas com feno ou haylage de Tifton-85 ( Cynodon spp.

    Directory of Open Access Journals (Sweden)

    T.C. Guimarães

    Full Text Available RESUMO O capim Tifton-85 (Cynodon spp. vem sendo utilizado na alimentação de equinos na forma de pré-secado (haylage e feno, todavia não existem estudos conclusivos a respeito da influência da haylage sobre o estado de saúde dessa espécie. Portanto, esta pesquisa objetivou avaliar o perfil sanguíneo como indicador de higidez de éguas Quarto de Milha alimentadas com haylage e feno de Tifton-85. A gramínea utilizada foi cortada com 30 dias de crescimento. Para produção da haylage, a planta cortada permaneceu no campo até atingir 70% de matéria seca, quando foi colhida. Foram utilizadas 12 éguas Quarto de Milha, com idade entre oito e 12 anos e com peso vivo médio inicial de 451,6kg. Os animais foram distribuídos aleatoriamente em dois grupos (n=6, sendo o grupo 1 alimentado com feno e o grupo 2 alimentado com haylage, por um período de 28 dias. Foram realizadas cinco coletas de sangue em intervalos de uma semana, para a determinação do perfil hematológico. Em relação ao eritrograma, observou-se discreta diminuição da concentração de hemoglobina, do hematócrito e do volume globular médio (VGM em ambos os grupos. No leucograma, houve aumento dos leucócitos totais nas coletas iniciais em ambos os grupos, mas sem significado clínico. Conclui-se que éguas adultas Quarto de Milha, após a ingestão de feno e haylage de Tifton-85, não apresentaram alterações no perfil hematológico que indicassem prejuízos à saúde.

  13. Evaluación del funcionamiento de motores de combustión interna trabajando con biodiesel.

    OpenAIRE

    R. Piloto Rodríguez; R. Sierens; S. Verhelst; N. Ferrer Frontela

    2008-01-01

    En el presente trabajo se determinó la característica exterior de velocidad para dos motores de combustión interna trabajando con combustible biodiesel procedente de varias fuentes naturales y se comparó con la característica exterior de velocidad de los motores originalmente trabajando con combustible diesel. Los motores fueron evaluados con variaciones de carga y velocidad. En uno de los motores ensayados fue determinada la presión en el interior de la cámara de combustión con el objetivo d...

  14. Transient flow combustion

    Science.gov (United States)

    Tacina, R. R.

    1984-01-01

    Non-steady combustion problems can result from engine sources such as accelerations, decelerations, nozzle adjustments, augmentor ignition, and air perturbations into and out of the compressor. Also non-steady combustion can be generated internally from combustion instability or self-induced oscillations. A premixed-prevaporized combustor would be particularly sensitive to flow transients because of its susceptability to flashback-autoignition and blowout. An experimental program, the Transient Flow Combustion Study is in progress to study the effects of air and fuel flow transients on a premixed-prevaporized combustor. Preliminary tests performed at an inlet air temperature of 600 K, a reference velocity of 30 m/s, and a pressure of 700 kPa. The airflow was reduced to 1/3 of its original value in a 40 ms ramp before flashback occurred. Ramping the airflow up has shown that blowout is more sensitive than flashback to flow transients. Blowout occurred with a 25 percent increase in airflow (at a constant fuel-air ratio) in a 20 ms ramp. Combustion resonance was found at some conditions and may be important in determining the effects of flow transients.

  15. 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.)

  16. 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.

  17. Optical Tomography in Combustion

    DEFF Research Database (Denmark)

    Evseev, Vadim

    spectral measurements at several line-of-sights with a view to applications for tomographic measurements on full-scale industrial combustion systems. The system was successfully applied on industrial scale for simultaneous fast exhaust gas temperature measurements in the three optical ports of the exhaust......D project, it was also important to investigate the spectral properties of major combustion species such as carbon dioxide and carbon monoxide in the infrared range at high temperatures to provide the theoretical background for the development of the optical tomography methods. The new software....... JQSRT 113 (2012) 2222, 10.1016/j.jqsrt.2012.07.015] included in the PhD thesis as an attachment. The knowledge and experience gained in the PhD project is the first important step towards introducing the advanced optical tomography methods of combustion diagnostics developed in the project to future...

  18. 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.

  19. Fuel and combustion stratification study of Partially Premixed Combustion

    OpenAIRE

    Izadi Najafabadi, M.; Dam, N.; Somers, B.; Johansson, B.

    2016-01-01

    Relatively high levels of stratification is one of the main advantages of Partially Premixed Combustion (PPC) over the Homogeneous Charge Compression Ignition (HCCI) concept. Fuel stratification smoothens heat release and improves controllability of this kind of combustion. However, the lack of a clear definition of “fuel and combustion stratifications” is obvious in literature. Hence, it is difficult to compare stratification levels of different PPC strategies or other combustion concepts. T...

  20. 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.

  1. High Gravity (g) Combustion

    Science.gov (United States)

    2006-02-01

    UNICORN (Unsteady Ignition and Combustion with Reactions) code10. Flame propagation in a tube that is 50-mm wide and 1000-mm long (similar to that...turbine engine manufacturers, estimating the primary zone space heating rate. Both combustion systems, from Company A and Company B, required a much...MBTU/atm-hr-ft3) Te m pe ra tu re R is e (K ) dP/P = 2% dP/P = 2.5% dP/P = 3% dP/P = 3.5% dP/P = 4% Company A Company B Figure 13: Heat Release Rate

  2. 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

  3. Combustibility of tetraphenylborate solids

    International Nuclear Information System (INIS)

    Walker, D.D.

    1989-01-01

    Liquid slurries expected under normal in-tank processing (ITP) operations are not ignitible because of their high water content. However, deposits of dry solids from the slurries are combustible and produce dense, black smoke when burned. The dry solids burn similarly to Styrofoam and more easily than sawdust. It is the opinion of fire hazard experts that a benzene vapor deflagration could ignite the dry solids. A tetraphenylborate solids fire will rapidly plug the waste tank HEPA ventilation filters due to the nature of the smoke produced. To prevent ignition and combustion of these solids, the waste tanks have been equipped with a nitrogen inerting system

  4. 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.

  5. 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

    achieved. [Espanol] La combustion de aceite combustible residual emite sustancias nocivas como particulas carbonaceas, oxidos de nitrogeno y trioxido de azufre, a niveles inadmisibles. Agua emulsionada en el combustible reduce sustancialmente dichas emisiones, lograndose ademas, en la mayoria de los casos, un ahorro neto en el consumo de combustible. Se muestran los efectos beneficos de quemar el aceite combustible residual en forma de emulsion, asi como el metodo para producir una emulsion adecuada. La tecnologia del combustible emulsionado ofrece una opcion de bajo costo para reducir la contaminacion atmosferica. La calidad del aceite combustible residual ha estado declinando durante las ultimas decadas debido: 1. Al aumento en la produccion de petroleos crudos pesados generalmente con mayor contenido de asfaltenos y de azufre. 2. A menor disponibilidad de residuos de la destilacion al vacio debido a su conversion a productos de mayor valor. 3. A procesos de conversion mas intensivos, como cracking catalitico, {sup v}isbreaking{sup ,} etc., que aumentan la concentracion de asfaltenos en los fondos, ocasionando problemas de inestabilidad. 4. Al aumento en el contenido de vanadio y de otros metales a medida que aumenta la concentracion de asfaltenos. El uso de aceite combustible emulsionado proporciona un medio eficaz y economico para reducir sustancialmente las emisiones nocivas a la atmosfera. La emulsion contiene particulas de agua de un diametro entre 2 y 20 micras, dispersadas uniformemente dentro del aceite combustible, en una proporcion generalmente enter 5 y 10%; ademas contiene un agente tensioactivo para asegurar una emulsion estable, capaz de resistir los esfuerzos cortantes del sistema de bombeo y distribucion. Cuando las gotas de aceite combustible atomizado llegan a la camara de combustion, el agua esmulsionada en ellas se convierte instantaneamente en vapor de alta presion, ocasionando una violenta atomizacion secundaria. El efecto de esta atomizacion

  6. Combustion stratification for naphtha from CI combustion to PPC

    NARCIS (Netherlands)

    Vallinayagam, R.; Vedharaj, S.; An, Y.; Dawood, A.; Izadi Najafabadi, M.; Somers, L.M.T.; Johansson, B.H.

    2017-01-01

    This study demonstrated the change in combustion homogeneity from conventional diesel combustion via partially premixed combustion towards HCCI. Experiments are performed in an optical diesel engine at a speed of 1200 rpm with diesel fuel. Single injection strategy is employed and the fuel is

  7. 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. ...

  8. Composição corporal e puberdade de leitoas alimentadas com níveis alto e baixo de proteína na dieta Body composition and puberty of gilts fed low and high protein diets

    Directory of Open Access Journals (Sweden)

    Fábio Enrique Lemos Budiño

    2001-10-01

    Full Text Available Com o objetivo de verificar alterarações na composição corporal, diferentes níveis protéicos (12 e 18% PB foram utilizados na dieta de leitoas de reposição, dos 100 aos 221 dias de idade. Durante esse período foram avaliados o peso corporal, espessura de toucinho (ET, manifestação de estro, características do trato reprodutivo e o balanço nitrogenado. Para a determinação do balanço nitrogenado, as leitoas foram submetidas a dois ensaios de digestibilidade (aos 136 e aos 201 dias de idade. Em ambos os ensaios, as leitoas alimentadas com 18% PB apresentaram maior ingestão, retenção e excreção de nitrogênio e maiores níveis de uréia plasmática e urinária (P0,05. Houve redução de 48% na excreção de nitrogênio com a dieta menos protéica. Leitoas alimentadas com 12% PB apresentaram maior ganho de ET (7,4 mm em comparação às alimentadas com 18% PB (4,5 mm, dos 100 aos 207 dias de idade (PWith the aim of altering body composition, diets with different protein levels (12 and 18 CP were offered to breeding gilts from 100 to 221 days of age. During this period, body weight, backfat thickness, oestrus manifestation, characteristics of reproductive tract and nitrogen balance were evaluated. Nitrogen balance was measured during two metabolism trials (at 136 and at 201 days of age. In both trials, gilts fed 18% CP showed higher nitrogen intake, retention and excretion and higher plasmatic and urinary urea levels (P.05. The low-protein diet reduced by 48% the excretion of nitrogen. Gilts fed 12% CP showed a greater backfat change (7.4 mm than those fed 18% CP (4.5 mm, between 100 and 207 days of age (P<.02. Body weight, uterine weight, uterine horns length and number of corpora lutea were not influenced by the level of dietary protein. The rate of oestrus detection, up to 25 days after male exposure, was similar to females receiving 12% (71% and 18% CP (75%. The protein level affected body composition without altering body

  9. Pilas de combustible de Membrana polimérica

    OpenAIRE

    Asensio, Juan; Peña, Juan; Pérez-Coll, Domingo; Ruiz-Morales, Juan; Marrero -López, David; Núñez, Pedro; Ballesteros, Belèn; Canales-Vázquez, Jesús; Borrós, Salvador; Gómez-Romero, Pedro

    2011-01-01

    En este trabajo revisamos brevemente las pilas de combustible poliméricas (PEM) basadas en membranas de intercambio protónico y que constituyen la tecnología idónea de pilas de combustible de baja temperatura, y por tanto las más adecuadas para aplicación en transporte. Revisaremos los materiales que las componen pero tambíen los desarrollos necesarios para su implantación definitiva en un mercado inclemente con las tecnologías caras, por límpias que sean.

  10. Underground treatment of combustible minerals

    Energy Technology Data Exchange (ETDEWEB)

    Sarapuu, E

    1954-10-14

    A process is described for treating oil underground, consisting in introducing several electrodes spaced one from the other in a bed of combustibles underground so that they come in electric contact with this bed of combustibles remaining insulated from the ground, and applying to the electrodes a voltage sufficient to produce an electric current across the bed of combustibles, so as to heat it and create an electric connection between the electrodes on traversing the bed of combustibles.

  11. Supersonic Combustion Ramjet Research

    Science.gov (United States)

    2012-08-01

    was in collaboration with Prof. R. Bowersox (Texas A&M University) and Dr. K. Kobayashi ( Japanese Aerospace Exploration Agency, JAXA). 4.2 Ignition... cinema stereoscopic PIV system for the measurement of micro- and meso-scale turbulent premixed flame dynamics,” Paper B13, 5th US Combustion

  12. Infrared monitoring of combustion

    International Nuclear Information System (INIS)

    Bates, S.C.; Morrison, P.W. Jr.; Solomon, P.R.

    1991-01-01

    In this paper, the use of Fourier Transform Infrared (FT-IR) spectroscopy for combustion monitoring is described. A combination of emission, transmission, and reflection FT-IR spectroscopy yields data on the temperature and composition of the gases, surfaces and suspended particles in the combustion environment. Detection sensitivity of such trace exhaust gases as CO, CO 2 , SO 2 , NO x , and unburned hydrocarbons is at the ppm level. Tomographic reconstruction converts line-of-sight measurements into spatially resolved temperature and concentration data. Examples from various combustion processes are used to demonstrate the capabilities of the technique. Industrial measurements are described that have been performed directly in the combustion zone and in the exhaust duct of a large chemical recovery boiler. Other measurements of hot slag show how FT-IR spectroscopy can determine the temperature and optical properties of surfaces. In addition, experiments with water droplets show that transmission FT-IR data yield spectra that characterize particle size and number density

  13. Combustible dust tests

    Science.gov (United States)

    The sugar dust explosion in Georgia on February 7, 2008 killed 14 workers and injured many others (OSHA, 2009). As a consequence of this explosion, OSHA revised its Combustible Dust National Emphasis (NEP) program. The NEP targets 64 industries with more than 1,000 inspections and has found more tha...

  14. Inserción de pilas de combustible de hidrógeno en un yate de 45 metros

    OpenAIRE

    Morera Castillo, Eduard

    2014-01-01

    Con este trabajo se persigue la reducción de la contaminación atmosférica producida por el sector marítimo y la presentación del hidrógeno y las pilas de combustible como alternativas a los combustibles fósiles y a los motores y generadores convencionales.

  15. Dietas a base de forraje tradicional y nopal (Opuntia spp. enriquecido con proteínas para alimentar cabras

    Directory of Open Access Journals (Sweden)

    Arnoldo Flores-Hernández

    2017-01-01

    Full Text Available El objetivo fue determinar la composición química de las dietas y su efecto en la ganancia de peso vivo, consumo y rechazo de alimento. El estudio se realizó mediante un diseño completamente azar con tres repeticiones y como factor principal tres dietas cuyos componentes fueron : dieta 1 40% heno de alfalfa + 60% heno de sorgo, dieta 2 40% nopal seco natural + 60 % heno de sorgo y dieta 3 40% nopal seco enriquecido co n proteínas + 60% heno de sorgo . Los resultados mostraron que la dieta de nopal enriquecido con proteínas y la dieta de nopal seco natural poseen una calidad nutritiva mayor, pero las condiciones de secado y/o almacenamiento tuvieron efecto en la calidad de l os componentes de las dietas evaluadas. La ganancia de peso vivo fue mayor en cabras alimentadas con la dieta de nopal - E , pero el porcentaje de alimento rechazado (menor palatabili dad fue mayor para esta dieta. La ganancia de peso vivo fue menor en alfalfa y nopal seco natural , respectivamente . La ganancia de peso y el tiempo de alimentación mostraron correlación positiva y significativa ; sin embargo, se debe determinar el tiempo óptimo de alimentación y evaluar el costo - beneficio de las dietas utilizadas.

  16. 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.

  17. 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.

  18. Hydrogen assisted diesel combustion

    Energy Technology Data Exchange (ETDEWEB)

    Lilik, Gregory K.; Boehman, Andre L. [The EMS Energy Institute, The Pennsylvania State University, University Park, PA 16802 (United States); Zhang, Hedan; Haworth, Daniel C. [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA 16802 (United States); Herreros, Jose Martin [Escuela Tecnica Superior de Ingenieros Industriales, Universidad de Castilla La-Mancha, Avda. Camilo Jose Cela s/n, 13071 Ciudad Real (Spain)

    2010-05-15

    Hydrogen assisted diesel combustion was investigated on a DDC/VM Motori 2.5L, 4-cylinder, turbocharged, common rail, direct injection light-duty diesel engine, with a focus on exhaust emissions. Hydrogen was substituted for diesel fuel on an energy basis of 0%, 2.5%, 5%, 7.5%, 10% and 15% by aspiration of hydrogen into the engine's intake air. Four speed and load conditions were investigated (1800 rpm at 25% and 75% of maximum output and 3600 rpm at 25% and 75% of maximum output). A significant retarding of injection timing by the engine's electronic control unit (ECU) was observed during the increased aspiration of hydrogen. The retarding of injection timing resulted in significant NO{sub X} emission reductions, however, the same emission reductions were achieved without aspirated hydrogen by manually retarding the injection timing. Subsequently, hydrogen assisted diesel combustion was examined, with the pilot and main injection timings locked, to study the effects caused directly by hydrogen addition. Hydrogen assisted diesel combustion resulted in a modest increase of NO{sub X} emissions and a shift in NO/NO{sub 2} ratio in which NO emissions decreased and NO{sub 2} emissions increased, with NO{sub 2} becoming the dominant NO{sub X} component in some combustion modes. Computational fluid dynamics analysis (CFD) of the hydrogen assisted diesel combustion process captured this trend and reproduced the experimentally observed trends of hydrogen's effect on the composition of NO{sub X} for some operating conditions. A model that explicitly accounts for turbulence-chemistry interactions using a transported probability density function (PDF) method was better able to reproduce the experimental trends, compared to a model that ignores the influence of turbulent fluctuations on mean chemical production rates, although the importance of the fluctuations is not as strong as has been reported in some other recent modeling studies. The CFD results confirm

  19. Determinación de la influencia en emisiones contaminantes, torque, potencia y consumo de combustible de un vehículo con motor ciclo Otto, de inyección electrónica de gasolina, mediante la variación de 6 tipos de bujías.

    OpenAIRE

    Serpa Andrade, Gabriel Fabián; Zumba Tenezaca, Xavier Alex

    2016-01-01

    La altitud ejerce efectos en la presión y temperatura atmosférica, y por ende en la concentración de oxígeno en el aire. La altitud disminuye la potencia indicada, y por lo tanto la potencia efectiva; además de incrementar el consumo específico de combustible. La investigación se enfoca en determinar la influencia en emisiones contaminantes, torque, potencia y consumo especifico de combustible del vehículo de mayor demanda en la ciudad de Cuenca (Chevrolet Grand Vitara 2.0L), mediante la vari...

  20. Combustion strategy : United Kingdom

    Energy Technology Data Exchange (ETDEWEB)

    Greenhalgh, D. [Heriot-Watt Univ., Edingburgh, Scotland (United Kingdom). School of Engineering and Physical Sciences

    2009-07-01

    The United Kingdom's combustion strategy was briefly presented. Government funding sources for universities were listed. The United Kingdom Research Councils that were listed included the Arts and Humanities Research Council (AHRC) and the Biotechnology and Biological Sciences Research Council (BBSRC); the Engineering and Physical Sciences Research Council (EPSRC); the Economic and Social Research Council; the Medical Research Council; the Natural Environment Research Council; and the Science and Technology Facilities Council. The EPSRC supported 65 grants worth 30.5 million pounds. The combustion industry was noted to be dominated by three main players of which one was by far the largest. The 3 key players were Rolls-Royce; Jaguar Land Rover; and Doosan Babcock. Industry and government involvement was also discussed for the BIS Technology Strategy Board, strategy technology areas, and strategy application areas.

  1. 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.

  2. Plasma Assisted Combustion

    Science.gov (United States)

    2007-02-28

    Tracking an individual streamer branch among others in a pulsed induced discharge J. Phys. D: Appl. Phys. 35 2823--9 [29] van Veldhuizen E M and Rutgers...2005) AIAA–2005–0405. [99] E.M. Van Veldhuizen (ed) Electrical Discharges for Environmental Purposes: Fun- damentals and Applications (New York: Nova...Vandooren J, Van Tiggelen P J 1977 Reaction Mechanism and Rate Constants in Lean Hydrogen–Nitrous Oxide Flames Combust. Flame 28 165 [201] Dean A M, Steiner

  3. 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.

  4. 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

  5. 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.

  6. Caracterización de combustibles leñosos en el ejido Pueblo Nuevo, Durango

    Directory of Open Access Journals (Sweden)

    J. Bautista Rentería-Anima

    2005-01-01

    Full Text Available Se realizó un inventario de combustibles leñosos en una microcuenca del ejido Pueblo Nuevo, Dgo., para determinar las cargas de combustibles con peligro de propiciar incendios forestales. Se utilizó la técnica de intersecciones planares y en el análisis se consideró la anualidad, tratamientos silvícolas, productividad, pendiente y exposición. Los resultados muestran un incremento en la acumulación de combustible total a partir de la extracción, alcanzando su nivel máximo al tercer año. Las mayores concentraciones de combustibles se presentan en los tratamientos de cortas de regeneración y aclareos, en aquellas áreas con la mayor productividad, en pendiente moderada.

  7. 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.

  8. 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.

  9. Influencias de las impurezas en los combustibles residuales

    Directory of Open Access Journals (Sweden)

    Carlos Losada

    2002-01-01

    Full Text Available A partir de considerar como campo experimental una planta generadora de electricidad que utiliza motores marinos MAN B&W L+V-28/32H, se demuestra que las impurezas formadas durante el proceso de fabricación, transportación, almacenamiento y consumo del combustible afectan la calidad de combustión y con ello los daños causados a los elementos del sistema.

  10. 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.

  11. Evaluación del funcionamiento de motores de combustión interna trabajando con biodiesel. // Evaluation of engine performance working with biodiesel.

    OpenAIRE

    R. Piloto Rodríguez; R. Sierens; S. Verhelst; N. Ferrer Frontela

    2008-01-01

    En el presente trabajo se determinó la característica exterior de velocidad para dos motores de combustión internatrabajando con combustible biodiesel procedente de varias fuentes naturales y se comparó con la característica exterior develocidad de los motores originalmente trabajando con combustible diesel. Los motores fueron evaluados con variacionesde carga y velocidad. En uno de los motores ensayados fue determinada la presión en el interior de la cámara decombustión con el objetivo de ev...

  12. Paciente con esquizofrenia tratado con ziprasidona + clozapina

    Directory of Open Access Journals (Sweden)

    Pol Yanguas E.

    2013-05-01

    Full Text Available P es un paciente diagnosticado de esquizofrenia, sigue en un piso tutelado un programa de rehabilitación, está medicado con clozapina 500 mg/día y ziprasidona 280 mg/ día. Padece hipercolesterolemia, tabaquismo y sus hábitos alimenticios no son buenos. La medicación que utiliza desde 2007 hasta ahora se refleja en la tabla 1. El último tratamiento se le introdujo el 7 de agosto de 2012, habiendo presentado un electro cardiograma (ECG normal, pero con ligera taquicardia ventricular y prolactinemia de 44,8 ng/ml (valores normales: 2-18 ng/ml.

  13. Sulfur Chemistry in Combustion I

    DEFF Research Database (Denmark)

    Johnsson, Jan Erik; Glarborg, Peter

    2000-01-01

    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...... process by reaction between SO2 and calcium containing sorbents and the influence on the NOx chemistry will be treated....

  14. 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

  15. 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

  16. 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.

  17. Combustion Byproducts Recycling Consortium

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-08-31

    Each year, over 100 million tons of solid byproducts are produced by coal-burning electric utilities in the United States. Annual production of flue gas desulfurization (FGD) byproducts continues to increase as the result of more stringent sulfur emission restrictions. In addition, stricter limits on NOx emissions mandated by the 1990 Clean Air Act have resulted in utility burner/boiler modifications that frequently yield higher carbon concentrations in fly ash, which restricts the use of the ash as a cement replacement. Controlling ammonia in ash is also of concern. If newer, “clean coal” combustion and gasification technologies are adopted, their byproducts may also present a management challenge. The objective of the Combustion Byproducts Recycling Consortium (CBRC) is to develop and demonstrate technologies to address issues related to the recycling of byproducts associated with coal combustion processes. A goal of CBRC is that these technologies, by the year 2010, will lead to an overall ash utilization rate from the current 34% to 50% by such measures as increasing the current rate of FGD byproduct use and increasing in the number of uses considered “allowable” under state regulations. Another issue of interest to the CBRC would be to examine the environmental impact of both byproduct utilization and disposal. No byproduct utilization technology is likely to be adopted by industry unless it is more cost-effective than landfilling. Therefore, it is extremely important that the utility industry provide guidance to the R&D program. Government agencies and privatesector organizations that may be able to utilize these materials in the conduct of their missions should also provide input. The CBRC will serve as an effective vehicle for acquiring and maintaining guidance from these diverse organizations so that the proper balance in the R&D program is achieved.

  18. The combustion of sodium

    International Nuclear Information System (INIS)

    Newman, R.N.

    1978-01-01

    The burning rates of sodium in the form of vapour jets, droplets, sprays and unconfined and confined pools have been reviewed. Attention has been paid to assessing the value of models in the various combustion modes. Additional models have been constructed for the descriptions of laminar and turbulent vapour jets, stationary droplets, forced convection over ambient pool fires together with correlations for peak pressures in confined pool environments. Where appropriate experiments with sodium have not been conducted, the likely behaviour is predicted by comparison with the burning of other fuels, particularly in the field of large free ambient fires. Some areas where further knowledge is required are highlighted. (author)

  19. Fluidised bed combustion system

    International Nuclear Information System (INIS)

    McKenzie, E.C.

    1976-01-01

    Fluidized bed combustion systems that facilitates the maintenance of the depth of the bed are described. A discharge pipe projects upwardly into the bed so that bed material can flow into its upper end and escape downwardly. The end of the pipe is surrounded by an enclosure and air is discharged into the enclosure so that material will enter the pipe from within the enclosure and have been cooled in the enclosure by the air discharged into it. The walls of the enclosure may themselves be cooled

  20. Fuel oil-water emulsions combustion and application perspectives in Mexico; Combustion de emulsiones de agua en combustoleo y perspectivas de aplicacion en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ocampo Barrera, Rene [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-09-01

    Fuel drops with a content of 16% by weight were burned in three emulsions prepared with 5%, 15% and 25% water. The combustion of the drops was carried out in an spherical furnace utilizing the technique of a drop suspended in a filament. The combustion process was registered by a high velocity video system. It was found that the surface of the particles produced by the combustion of the emulsions, had larger holes than the ones of the fuel, therefore it is expected that emulsifying the fuel can help in reducing the unburned particles emission. [Espanol] Se quemaron gotas de un combustoleo, con un contenido de asfaltenos del 16% en peso, y de tres emulsiones preparadas con 5%, 15% y 25% de agua. La combustion de las gotas se llevo a cabo en un horno esferico empleando la tecnica de gota suspendida en un filamento. El proceso de combustion se registro mediante un sistema de video de alta velocidad. Se encontro que la superficie de las particulas de coque, producidas por la combustion de emulsiones, tuvo hoyos mas grandes que la del combustoleo, por lo que es de esperarse que emulsionar el combustoleo puede ayudar a reducir las emisiones de particulas inquemadas.

  1. Fuel and combustion stratification study of Partially Premixed Combustion

    NARCIS (Netherlands)

    Izadi Najafabadi, M.; Dam, N.; Somers, B.; Johansson, B.

    2016-01-01

    Relatively high levels of stratification is one of the main advantages of Partially Premixed Combustion (PPC) over the Homogeneous Charge Compression Ignition (HCCI) concept. Fuel stratification smoothens heat release and improves controllability of this kind of combustion. However, the lack of a

  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. Dinámica de la humedad de los combustibles y su relación con la ecología y manejo de fuego, region chaqueña occidental (Argentina) II: follaje y residuos de árboles y arbustos

    OpenAIRE

    Kunst, Carlos Roberto Guillermo; Ledesma, Ramona Ofelia; Bravo, S.; Defossé, Guillermo Emilio; Godoy, J.; Navarrete, V.

    2017-01-01

    El fuego es fenómeno frecuente en la región chaqueña argentina. El contenido de agua (CH, %) es un factor que define la inflamabilidad de los combustibles vegetales, y sus cambios en magnitud pueden ser usados para comprender la ecología y régimen del fuego en una región, para planificar su uso como prescripto; o como un indicador de riesgo para su prevención. En este trabajo se evaluó la dinámica de CH a través del tiempo del follaje (combustible vivo), hojarasca y residuos leñosos de distin...

  4. Dinámica de la humedad de los combustibles y su relación con la ecologíay manejo de fuego, region chaqueña occidental (Argentina) II: follaje y residuos de árboles y arbustos

    OpenAIRE

    KUNST,C; LEDESMA, R; BRAVO, S.; DEFOSSÉ, G.; GODOY, J.; NAVARRETE, V.

    2014-01-01

    El fuego es fenómeno frecuente en la región chaqueña argentina. El contenido de agua (CH, %) es un factor que define la inflamabilidad de los combustibles vegetales, y sus cambios en magnitud pueden ser usados para comprender la ecología y régimen del fuego en una región, para planificar su uso como prescripto; o como un indicador de riesgo para su prevención. En este trabajo se evaluó la dinámica de CH a través del tiempo del follaje (combustible vivo), hojarasca y residuos leñosos de distin...

  5. Specific model for a gas distribution analysis in the containment at Almaraz NPP using GOTHIC computer code; Modelo de un sistema de control de gases combustibles en el edificio de contención, previsto específicamente para C.N. Almaraz con el código GOTHI

    Energy Technology Data Exchange (ETDEWEB)

    García González, M.; García Jiménez, P.; Martínez Domínguez, F.

    2016-07-01

    To carry out an analysis of the distribution of gases within the containment building at the CN Almaraz site, a simulation model with the thermohydraulic GOTHIC [1] code has been used. This has been assessed with a gas control system based on passive autocatalytic recombiners (PARs). The model is used to test the effectiveness of the control systems for gases to be used in the Almaraz Nuclear Power Plant, Uits I&II (Caceres, Spain, 1,035 MW and 1,044 MW). The model must confirm the location and number of the recombiners proposed to be installed. It is an essential function of the gas control system to avoid any formation of explosive atmospheres by reducing and limiting the concentration of combustible gases during an accident, thus maintaining the integrity of the containment. The model considers severe accident scenarios with specific conditions that produce the most onerous generation of combustible gases.

  6. Magnox Fuel Cycles; Cycles des combustibles gaines de magnox; Toplivnye tsikly magnoks; Ciclos de combustible magnox

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, A. [United Kingdom Atomic Energy Authority, Risley, Warrington, Lancs (United Kingdom)

    1963-10-15

    esquemas de irradiacion que se producen segun los diversos programas de carga del combustible, y describe someramente los metodos de calculo utilizados en la actualidad. Compara diversos programas de carga continua o intermitente del combustible. Estudia el problema de la irradiacion eficiente de la primera carga, junto con los metodos de reabastecimiento retardado y de transposicion de los elementos combustibles. Discute las ventajas economicas y los problemas que plantea la utilizacion de uranio, no natural en reactores de flujo nivelado. Formula consideraciones de orden practico sobre la carga de combustible durante la marcha en reactores nuevos y hace referencia a la experiencia adquirida en Bradwell y en Berkeley. Describe someramente el efecto que ejercen las variaciones del costo del combustible y de su resistencia sobre los aspectos economicos del ciclo de combustible. (author) [Russian] Rassmatrivaetsya vzaim o zavisimost' mezhdu potokom izlucheniya i temperaturnym raspredeleniem i kharakteristikami oblucheniya, vyzvannaya razlichnoj praktikoj zameny topliva, opisyvayutsya sushchestvuyushchie metody rascheta. Provoditsya sravnenie razlichnykh skhem zameny topliva, vklyuchaya kak sistemu vygruzki topliva portsiyami, tak i sistemu nepreryvnoj vygruzki. Problema ehffektivnogo oblucheniya pervoj zagruzki rassmatrivaetsya vmeste so skhemami zapazdyvayushchej nachal'noj zameny topliva i ego peremeshcheniya. Rassmatrivayutsya ehkonomicheskie preimushchestva i trudnosti ispol'zovaniya neprirodnogo urana v vyrovnennykh reaktorakh. Rassmatrivaetsya prakticheskoe reshenie skhemy zameny topliva na novykh reaktorakh i delaetsya ssylka na opyt, priobretennyj v Braduehlle i Berkli. Opisyvaetsya vliyani razlichnoj stoimosti topliva i prodolzhitel'nosti kampanii za ehkonomichnost' toplivnogo tsikla. (author)

  7. 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.

  8. Preliminary assessment of combustion modes for internal combustion wave rotors

    Science.gov (United States)

    Nalim, M. Razi

    1995-01-01

    Combustion within the channels of a wave rotor is examined as a means of obtaining pressure gain during heat addition in a gas turbine engine. Several modes of combustion are considered and the factors that determine the applicability of three modes are evaluated in detail; premixed autoignition/detonation, premixed deflagration, and non-premixed compression ignition. The last two will require strong turbulence for completion of combustion in a reasonable time in the wave rotor. The compression/autoignition modes will require inlet temperatures in excess of 1500 R for reliable ignition with most hydrocarbon fuels; otherwise, a supplementary ignition method must be provided. Examples of combustion mode selection are presented for two core engine applications that had been previously designed with equivalent 4-port wave rotor topping cycles using external combustion.

  9. Path planning during combustion mode switch

    Science.gov (United States)

    Jiang, Li; Ravi, Nikhil

    2015-12-29

    Systems and methods are provided for transitioning between a first combustion mode and a second combustion mode in an internal combustion engine. A current operating point of the engine is identified and a target operating point for the internal combustion engine in the second combustion mode is also determined. A predefined optimized transition operating point is selected from memory. While operating in the first combustion mode, one or more engine actuator settings are adjusted to cause the operating point of the internal combustion engine to approach the selected optimized transition operating point. When the engine is operating at the selected optimized transition operating point, the combustion mode is switched from the first combustion mode to the second combustion mode. While operating in the second combustion mode, one or more engine actuator settings are adjusted to cause the operating point of the internal combustion to approach the target operating point.

  10. 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...

  11. 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.

  12. 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.

  13. 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.

  14. 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...

  15. Rentabilidad de la producción de carne de ovinos Katahdin x Pelibuey con tres tipos de alimentación

    Directory of Open Access Journals (Sweden)

    R. González-Garduño

    2013-01-01

    Full Text Available El objetivo de este trabajo fue determinar la rentabilidad económica de la producción de carne de ovino Katahdin x Pelibuey comparando diferentes tipos de alimentación. Los indicadores se obtuvieron de una unidad de producción con un sistema semi-intensivo tecnificado de estrato socioeconómico medio. Se utilizaron los registros productivos de ovinos en tres experimentos diferentes: a pastoreo con suplementación, b estabulación con una dieta integral de sacchasorgo y c estabulación con alimento comercial. En cada tipo de alimentación se registró el consumo diario individual, y el peso de los corderos cada quince días. Para determinar la rentabilidad se utilizó la Matriz de Análisis de Política (map, donde los ingresos y los costos fueron evaluados a precios de mercado. En la producción de un kilogramo de carne, los insumos comerciables representaron mayor porcentaje en ovinos estabulados (90% respecto de los ovinos en pastoreo (48%. El mayor costo correspondió a la alimentación en todos los casos. En estabulación, los factores internos representaron de 7 a 9% y los costos fijos cerca del 1%; mientras que en ovinos en pastoreo estos indicadores representaron el 38% y 14%, respectivamente. La rentabilidad privada fue de 132% en corderos en pastoreo, 4% en corderos alimentados con sacchasorgo, -11.70% en hembras alimentadas con sacchasorgo y -12.30% en los machos que recibieron alimento comercial. Se concluye que la producción de carne es rentable en corderos en pastoreo y en los machos alimentados con una dieta integral de sacchasorgo, ya que todos los indicadores resultaron positivos.

  16. Combustion instability control in the model of combustion chamber

    International Nuclear Information System (INIS)

    Akhmadullin, A N; Ahmethanov, E N; Iovleva, O V; Mitrofanov, G A

    2013-01-01

    An experimental study of the influence of external periodic perturbations on the instability of the combustion chamber in a pulsating combustion. As an external periodic disturbances were used sound waves emitted by the electrodynamics. The purpose of the study was to determine the possibility of using the method of external periodic perturbation to control the combustion instability. The study was conducted on a specially created model of the combustion chamber with a swirl burner in the frequency range from 100 to 1400 Hz. The study found that the method of external periodic perturbations may be used to control combustion instability. Depending on the frequency of the external periodic perturbation is observed as an increase and decrease in the amplitude of the oscillations in the combustion chamber. These effects are due to the mechanisms of synchronous and asynchronous action. External periodic disturbance generated in the path feeding the gaseous fuel, showing the high efficiency of the method of management in terms of energy costs. Power required to initiate periodic disturbances (50 W) is significantly smaller than the thermal capacity of the combustion chamber (100 kW)

  17. Space Station Freedom combustion research

    Science.gov (United States)

    Faeth, G. M.

    1992-01-01

    Extended operations in microgravity, on board spacecraft like Space Station Freedom, provide both unusual opportunities and unusual challenges for combustion science. On the one hand, eliminating the intrusion of buoyancy provides a valuable new perspective for fundamental studies of combustion phenomena. On the other hand, however, the absence of buoyancy creates new hazards of fires and explosions that must be understood to assure safe manned space activities. These considerations - and the relevance of combustion science to problems of pollutants, energy utilization, waste incineration, power and propulsion systems, and fire and explosion hazards, among others - provide strong motivation for microgravity combustion research. The intrusion of buoyancy is a greater impediment to fundamental combustion studies than to most other areas of science. Combustion intrinsically heats gases with the resulting buoyant motion at normal gravity either preventing or vastly complicating measurements. Perversely, this limitation is most evident for fundamental laboratory experiments; few practical combustion phenomena are significantly affected by buoyancy. Thus, we have never observed the most fundamental combustion phenomena - laminar premixed and diffusion flames, heterogeneous flames of particles and surfaces, low-speed turbulent flames, etc. - without substantial buoyant disturbances. This precludes rational merging of theory, where buoyancy is of little interest, and experiments, that always are contaminated by buoyancy, which is the traditional path for developing most areas of science. The current microgravity combustion program seeks to rectify this deficiency using both ground-based and space-based facilities, with experiments involving space-based facilities including: laminar premixed flames, soot processes in laminar jet diffusion flames, structure of laminar and turbulent jet diffusion flames, solid surface combustion, one-dimensional smoldering, ignition and flame

  18. Dinámica de la humedad de los combustibles y su relación con la ecología y el manejo de fuego en la región chaqueña occidental (Argentina) I: conceptos básicos

    OpenAIRE

    DEFOSSÉ, G.; BIANCHI, L.; DENTONI M.; KUNST, C.; LEDESMA, R.; BRAVO, S.

    2014-01-01

    El fuego es un modelador de la mayoría de los ecosistemas vegetales del mundo, entre ellos, los correspondientes a la región chaqueña argentina donde asimismo ha sido usado ampliamente como una herramienta de manejo de la vegetación. Dada una fuente de ignición, para que un fuego pueda prosperar deben existir ciertas condiciones. Entre ellas, el contenido de humedad del combustible (CH) juega un rol fundamental ya que su magnitud influirá en la probabilidad de ignición, en el posterior compor...

  19. 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.

  20. Videojuego con Realidad Virtual

    OpenAIRE

    González Mora, César

    2017-01-01

    El objetivo del proyecto es el desarrollo de un videojuego deportivo que utilice realidad mixta. El videojuego se podrá utilizar con dispositivos de tipo cardboard, y utilizará realidad aumentada para la interacción del jugador con el videojuego. En el desarrollo se utilizará el motor Unity para conseguir una aplicación multiplataforma, y la librería Vuforia para implementar realidad mixta.

  1. Sistemas integrados con Arduino

    OpenAIRE

    EL YAKOUTI, MOHAMMED

    2017-01-01

    Design of a robot prototype remotely controllable from Bluetooth using Arduino. Control and testing of sensors and events interacting with Arduino and Bluetooth. Diseño de un prototipo de robot controlable remotamente con Bluetooth utilizando Arduino. Control y verificación de los sensores y eventos que interactúan mediante el Arduino y el Bluetooth. El Yakouti, M. (2017). Sistemas integrados con Arduino. http://hdl.handle.net/10251/89274. TFGM

  2. Hydraulic modelling of the CARA Fuel element; Desarrollo hidraulico del combustible CARA

    Energy Technology Data Exchange (ETDEWEB)

    Brasnarof, Daniel O; Juanico, Luis [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Disenios Avanzados y Evaluacion Economica; Giorgi, M [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Materiales; Ghiselli, Alberto M; Zampach, Ruben; Fiori, Jose M; Yedros, Pablo A [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Ensayos no Destructivos

    2004-07-01

    The CARA fuel element is been developing by the National Atomic Energy Commission for both Argentinean PHWRs. In order to keep the hydraulic restriction in their fuel channels, one of CARA's goals is to keep its similarity with both present fuel elements. In this paper is presented pressure drop test performed at a low-pressure facility (Reynolds numbers between 5x10{sup 4} and 1,5x10{sup 5}) and rational base models for their spacer grid and rod assembly. Using these models, we could estimate the CARA hydraulic performance in reactor conditions that have shown to be satisfactory. (author) [Spanish] Con el objeto de validar la similitud hidraulica del elemento combustible CARA con los actuales combustibles de Atucha y Embalse, se realizaron ensayos de perdida de carga en el circuito CBP del CAC con un nuevo diseno de separador de mejor desempeno hidraulico. Se presenta aqui el analisis de los mismos, de los cuales se validaron modelos de base racional para estimar las restricciones hidraulicas de los distintos componentes estructurales (separadores, grillas y barras combustibles) en funcion del flujo refrigerante. Se estimo asi la caida de presion del CARA dentro del canal combustible Embalse en condiciones nominales de reactor, siendo la misma similar al del combustible actual de 37 barras. (autor)

  3. Producer for vegetal combustibles for internal-combustion motors

    Energy Technology Data Exchange (ETDEWEB)

    1943-12-28

    A producer is described for internal-combustion motors fed with wood or agricultural byproducts characterized by the fact that its full operation is independent of the degree of wetness of the material used.

  4. Reducing emissions from diesel combustion

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper contains information dealing with engine design to reduce emissions and improve or maintain fuel economy. Topics include: Observation of High Pressure Fuel Spray with Laser Light Sheet Method; Determination of Engine Cylinder Pressures from Crankshaft Speed Fluctuations; Combustion Similarity for Different Size Diesel Engines: Theoretical Prediction and Experimental Results; Prediction of Diesel Engine Particulate Emission During Transient Cycles; Characteristics and Combustibility of Particulate Matter; Dual-Fuel Diesel Engine Using Butane; Measurement of Flame Temperature Distribution in D.I. Diesel Engine with High Pressure Fuel Injection: and Combustion in a Small DI Diesel Engine at Starting

  5. Investigando con personas con dificultades de aprendizaje

    Directory of Open Access Journals (Sweden)

    Borja González Luna

    2013-12-01

    Full Text Available El artículo muestra los orígenes de lo que Walmsley (2008 denomina «investigación inclusiva». Para comprender qué se entiende por investigación inclusiva tenemos que remontarnos a los debates epistemológicos sobre las metodologías cuantitativas y cualitativas, acontecidos en la década de los 90, en torno a la revista Disability & Society. A partir de una síntesis de dichos debates, focalizados en el ámbito de la «discapacidad intelectual y del desarrollo», se exponen dos estrategias de colaboración con dicha población: a una aproximación etnográfica (de trabajo grupal, y b una aproximación biográfica (de trabajo individual. A continuación se esboza un posible diseño de trabajo de campo que intenta superar el paradigma cualitativo «clásico» con el objetivo de incluir a dicho colectivo más allá del rol de «sujetos de la investigación». Para finalizar se recoge el debate sobre la accesibilidad de los resultados de la investigación a los participantes en dichas investigaciones, y con ello la necesaria innovación en el ámbito de las «devoluciones» de los resultados, cuando se trata de incluir a personas que presentan limitaciones para la comprensión del lenguaje abstracto oral y/o escrito.

  6. Calidad de los combustibles en Colombia

    Directory of Open Access Journals (Sweden)

    Jorge Humberto Arango

    2009-05-01

    Full Text Available Para conocer el estado actual de los combustibles usados en Colombia y para conocer las necesidades en el marco de los biocombustibles, el Ingeniero Jorge Humberto Arango, gerente de refinados de Ecopetrol, presenta un resumen de la calidad de la gasolina, diesel, biodiesel, y el gas natural, tomando en cuenta aspectos tales como el contenido de azufre, la presencia de aromáticos y la emisión de material particulado. En resumen, se muestra el interesante e importante trabajo de Ecopetrol desde los años 90, relacionado con el cumplimento de los estándares nacionales e internacionales. Por ejemplo, para el caso de diesel, Colombia muestra uno de los contenidos más bajos en azufre con respecto a Latinoamérica, llegando a niveles de 500 ppm para la ciudad de Bogotá. Para el caso de aromáticos en gasolina, Colombia presenta una de las mejores en el mundo en términos de aromáticos, con contenidos de gasolina regular en 20% y en gasolina Premium en 22 %. Por otro lado, la emisión de compuestos azufrados y material particulado no se está reduciendo en la misma proporción que la calidad de los combustibles colombianos, que están siendo mejorados especialmente en parque automotor de trasporte pesado antiguo (mayor de 25 años. / In order to acquire a brief understanding of the state o the fuels in Colombia and then frame the necessities for biofuels, the engineer Jorge Humberto Arango, fuels refining manager at Ecopetrol, displayed a summary regarding the work carried out by Ecopetrol during the last decade to improve the quality of gas, diesel, biodiesel, and natural gas by analyzing aspects such as sulfur and aromatics presence, and particle matter emissions when fueling motors. For example, sulfur concentration for Diesel reaches one of the lowest reported in Latinamerica (500 ppm moreover, the aromatics content in Colombian gasoline projects it as one of the best in world (regular gasoline, 20 % and Premium 22 %. On the other hand, even

  7. Development and testing of synthetic riprap constructed from coal combustion products (CCPs).

    Science.gov (United States)

    2014-07-01

    Even with an increase in the amount of coal combustion products (CCPs) used in concrete con-struction, soil stabilization, and other : applications, the coal power industry must dispose of a sig-nificant amount of fly ash and bottom ash. One potentia...

  8. 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,

  9. 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

  10. Fuels and Combustion | Transportation Research | NREL

    Science.gov (United States)

    Fuels and Combustion Fuels and Combustion This is the March 2015 issue of the Transportation and , combustion strategy, and engine design hold the potential to maximize vehicle energy efficiency and performance of low-carbon fuels in internal combustion engines with a whole-systems approach to fuel chemistry

  11. Emulsified fuels. Its use in stationary sources; Combustibles emulsionados. Su utilizacion en fuentes estacionarias

    Energy Technology Data Exchange (ETDEWEB)

    Campos Morales, Gilberto; Magdaleno Molina, Moises; Vargas Y, Victor M; Gavira D, A [Instituto Mexicano del Petroleo, Mexico, D. F. (Mexico)

    1993-12-31

    Basic aspects are set forth of the heavy hydrocarbon fuels, the principles, preparation and particularities of the combustion with emulsions, that currently represent one option, either by themselves or in combination with other technologies to utilize heavy hydrocarbons, obtaining advantages in the reduction of polluting emissions, particulate matter and NOx, which allow continuing operating the operation within the limits established by the technical ecological standards. [Espanol] Se exponen aspectos basicos de los combustibles de hidrocarburos pesados (HC), los principios, preparacion y particularidades de la combustion con emulsiones, que actualmente representan una alternativa por si solos o en combinacion con otras tecnologias para utilizar hidrocarburos pesados, obteniendose ventajas en la reduccion de emisiones de contaminantes de particulas y NOx, lo cual permite continuar operando dentro de los limites que establecen las normas tecnicas ecologicas.

  12. Emulsified fuels. Its use in stationary sources; Combustibles emulsionados. Su utilizacion en fuentes estacionarias

    Energy Technology Data Exchange (ETDEWEB)

    Campos Morales, Gilberto; Magdaleno Molina, Moises; Vargas Y, Victor M.; Gavira D, A. [Instituto Mexicano del Petroleo, Mexico, D. F. (Mexico)

    1992-12-31

    Basic aspects are set forth of the heavy hydrocarbon fuels, the principles, preparation and particularities of the combustion with emulsions, that currently represent one option, either by themselves or in combination with other technologies to utilize heavy hydrocarbons, obtaining advantages in the reduction of polluting emissions, particulate matter and NOx, which allow continuing operating the operation within the limits established by the technical ecological standards. [Espanol] Se exponen aspectos basicos de los combustibles de hidrocarburos pesados (HC), los principios, preparacion y particularidades de la combustion con emulsiones, que actualmente representan una alternativa por si solos o en combinacion con otras tecnologias para utilizar hidrocarburos pesados, obteniendose ventajas en la reduccion de emisiones de contaminantes de particulas y NOx, lo cual permite continuar operando dentro de los limites que establecen las normas tecnicas ecologicas.

  13. Empleo de combustibles alternativos en la fabricación de cemento. Efecto en las características y propiedades de los clínkeres y cementos

    OpenAIRE

    Puertas, F.; Blanco-Varela, M. T.

    2004-01-01

    [ES] Se han estudiado clínkeres y cementos obtenidos en procesos industriales que han utilizado combustibles convencionales y combustibles alternativos (harinas cárnicas, neumáticos usados y mezclas de ambos). Los resultados obtenidos han demostrado que los clínkeres fabricados con los combustibles alternativos no presentan diferencias significativas en la composición mineralógica respecto a los obtenidos con combustibles convencionales. Los contenidos de metales pesados en los clínkeres proc...

  14. Combustion modeling in waste tanks

    International Nuclear Information System (INIS)

    Mueller, C.; Unal, C.; Travis, J.R.; Forschungszentrum Karlsruhe

    1997-01-01

    This paper has two objectives. The first one is to repeat previous simulations of release and combustion of flammable gases in tank SY-101 at the Hanford reservation with the recently developed code GASFLOW-II. The GASFLOW-II results are compared with the results obtained with the HMS/TRAC code and show good agreement, especially for non-combustion cases. For combustion GASFLOW-II predicts a steeper pressure rise than HMS/TRAC. The second objective is to describe a so-called induction parameter model which was developed and implemented into GASFLOW-II and reassess previous calculations of Bureau of Mines experiments for hydrogen-air combustion. The pressure time history improves compared with the one-step model, and the time rate of pressure change is much closer to the experimental data

  15. Environmental sensing and combustion diagnostics

    International Nuclear Information System (INIS)

    Santoleri, J.J.

    1991-01-01

    This book contains proceedings of Environmental Sensing and Combustion Diagnostics. Topics covered include: Incineration Systems Applications, Permitting, And Monitoring Overview; Infrared Techniques Applied to Incineration Systems; Continuous Emission Monitors; Analyzers and Sensors for Process Control And Environmental Monitoring

  16. Sodium nitrate combustion limit tests

    International Nuclear Information System (INIS)

    Beitel, G.A.

    1976-04-01

    Sodium nitrate is a powerful solid oxidant. Energetically, it is capable of exothermically oxidizing almost any organic material. Rate-controlling variables such as temperature, concentration of oxidant, concentration of fuel, thermal conductivity, moisture content, size, and pressure severely limit the possibility of a self-supported exothermic reaction (combustion). The tests reported in this document were conducted on one-gram samples at atmospheric pressure. Below 380 0 C, NaNO 3 was stable and did not support combustion. At moisture concentrations above 22 wt percent, exothermic reactions did not propagate in even the most energetic and reactive compositions. Fresh resin and paraffin were too volatile to enable a NaNO 2 -supported combustion process to propagate. Concentrations of NaNO 3 above 95 wt percent or below 35 wt percent did not react with enough energy release to support combustion. The influence of sample size and confining pressure, both important factors, was not investigated in this study

  17. 75 FR 3881 - Combustible Dust

    Science.gov (United States)

    2010-01-25

    ..., rubber, drugs, dried blood, dyes, certain textiles, and metals (such as aluminum and magnesium..., furniture manufacturing, metal processing, fabricated metal products and machinery manufacturing, pesticide... standard that will comprehensively address the fire and explosion hazards of combustible dust. The Agency...

  18. Modeling of microgravity combustion experiments

    Science.gov (United States)

    Buckmaster, John

    1995-01-01

    This program started in February 1991, and is designed to improve our understanding of basic combustion phenomena by the modeling of various configurations undergoing experimental study by others. Results through 1992 were reported in the second workshop. Work since that time has examined the following topics: Flame-balls; Intrinsic and acoustic instabilities in multiphase mixtures; Radiation effects in premixed combustion; Smouldering, both forward and reverse, as well as two dimensional smoulder.

  19. Quantifying emissions from spontaneous combustion

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-09-01

    Spontaneous combustion can be a significant problem in the coal industry, not only due to the obvious safety hazard and the potential loss of valuable assets, but also with respect to the release of gaseous pollutants, especially CO2, from uncontrolled coal fires. This report reviews methodologies for measuring emissions from spontaneous combustion and discusses methods for quantifying, estimating and accounting for the purpose of preparing emission inventories.

  20. Combustion means for solid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Murase, D.

    1987-09-23

    A combustion device for solid fuel, suitable for coal, coke, charcoal, coal-dust briquettes etc., comprising:- a base stand with an opening therein, an imperforate heat resistant holding board locatable to close said opening; a combustion chamber standing on the base stand with the holding board forming the base of the combustion chamber; a wiper arm pivoted for horizontal wiping movement over the upper surface of the holding board; an inlet means at a lower edge of said chamber above the base stand, and/or in a surrounding wall of said chamber, whereby combustion air may enter as exhaust gases leave the combustion chamber; an exhaust pipe for the exhaust gases; generally tubular gas-flow heat-exchange ducting putting the combustion chamber and exhaust pipe into communication; and means capable of moving the holding board into and out of the opening for removal of ash or other residue. The invention can be used for a heating system in a house or in a greenhouse or for a boiler.

  1. 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

  2. Giochiamo con i robot

    Directory of Open Access Journals (Sweden)

    Andrea Bonarini

    2009-01-01

    Full Text Available "Giochiamo con i robot" e' un laboratorio interattivo per grandi e piccini realizzato per l'edizione 2007 del Festival della Scienza di Genova. Lungo un percorso che va dalla telerobotica alla robotica evolutiva, il laboratorio sviluppa il tema di dare intelligenza ai robot. Questo percorso, le cui tappe sono le varie installazioni, si conclude nella "bottega" dove e' possibile costruire e programmare i propri robot o smontare e modificare quelli esposti durante il percorso didattico. I visitatori sono coinvolti in attivita' ludiche grazie alle quali possonoentrare in contatto con alcune delle idee potenti della robotica,

  3. disegnare con ... Alberto Pratelli

    Directory of Open Access Journals (Sweden)

    Roberto Mingucci

    2017-12-01

    Full Text Available Con questa breve intervista ad Alberto Pratelli, (non a caso scelto per aprire questa nuova rubrica intendia-mo inaugurare un dialogo con personalità significati-ve del Disegno di Architettura, che consenta riflessioni dedicate alle sue varie dimensioni, oggi più che mai da approfondire. La suggestione a farlo, viene da un’idea di Pablo Rodri-guez Navarro ed abbiamo quindi pensato di avviarla proprio in questo numero, che Pablo ha accettato di curare su un tema a lui particolarmente caro.

  4. 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

  5. HERCULES Advanced Combustion Concepts Test Facility: Spray/Combustion Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Herrmann, K. [Eidgenoessische Technische Hochschule (ETH), Labor fuer Aerothermochemie und Verbrennungssysteme, Zuerich (Switzerland)

    2004-07-01

    This yearly report for 2004 on behalf of the Swiss Federal Office of Energy (SFOE) at the Laboratory for Aero-thermochemistry and Combustion Systems at the Federal Institute of Technology ETH in Zurich, Switzerland, presents a review of work being done within the framework of HERCULES (High Efficiency R and D on Combustion with Ultra Low Emissions for Ships) - the international R and D project concerning new technologies for ships' diesels. The work involves the use and augmentation of simulation models. These are to be validated using experimental data. The report deals with the development of an experimental set-up that will simulate combustion in large two-stroke diesel engines and allow the generation of reference data. The main element of the test apparatus is a spray / combustion chamber with extensive possibilities for optical observation under variable flow conditions. The results of first simulations confirm concepts and shall help in further work on the project. The potential offered by high-speed camera systems was tested using the institute's existing HTDZ combustion chamber. Further work to be done is reviewed.

  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. Twenty-fifth symposium (international) on combustion

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    Approximately two-thirds of the papers presented at this conference are contained in this volume. The other one-third appear in special issues of ''Combustion and Flame'', Vol. 99, 1994 and Vol. 100, 1995. Papers are divided into the following sections: Supersonic combustion; Detonations and explosions; Internal combustion engines; Practical aspects of combustion; Incineration and wastes; Sprays and droplet combustion; Coal and organic solids combustion; Soot and polycyclic aromatic hydrocarbons; Reaction kinetics; NO x ; Turbulent flames; Turbulent combustion; Laminar flames; Flame spread, fire and halogenated fire suppressants; Global environmental effects; Ignition; Two-phase combustion; Solid propellant combustion; Materials synthesis; Microgravity; and Experimental diagnostics. Papers have been processed separately for inclusion on the data base

  8. Conversando con Oriol Bohigas

    OpenAIRE

    Redondo Domínguez, Ernesto; Moya Sala, Joaquim

    2015-01-01

    [EN] Interview with Oriol Bohigas [ES] Entrevista con Oriol Bohigas Redondo Domínguez, E.; Moya Sala, J. (2015). Conversando con… Oriol Bohigas. EGA. Revista de Expresión Gráfica Arquitectónica. 20(26):22-35. doi:10.4995/ega.2015.4061 22 35 20 26

  9. DR Con o:

    African Journals Online (AJOL)

    which could fall under the Ugandan influence. The con-. flict in the ..... The Congolese people and international community within SADC, the AU ..... ments and make peace among themselves. However, one ... friends overnight.There is a great ...

  10. fertilizada con diferentes abonos

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Elizondo-Salazar

    2007-01-01

    Full Text Available Producción y calidad de la biomasa de morera (Morus alba fertilizada con diferentes abonos. Se llevó a cabo un experimento en la Estación Experimental “Alfredo Volio Mata” de la Universidad de Costa Rica con el fi n de evaluar la aplicación de 150 kg de N/ha/año proveniente de dos abonos orgánicos: lombriabono y compostaje; y de un fertilizante químico, sobre la producción y calidad de la biomasa de morera. El periodo experimental comprendió un ciclo de 12 meses, iniciando en julio del 2003 y fi nalizando en julio del 2004. Se utilizó una plantación de morera de 12 años de establecida con una densidad de siembra de 27.777 plantas/ ha. Se empleó un diseño de bloques completos al azar con cuatro tratamientos: dos abonos orgánicos, nitrato de amonio (33,5% N y un control. Las plantas se podaron a 0,6 m sobre el nivel del suelo al inicio del ensayo. Durante el periodo experimental, las plantas fueron podadas consecutivamente cada 90 días. Las hojas y los tallos fueron separados y analizados para determinar el contenido de materia seca y proteína cruda. La producción de materia seca fue 23% superior y el contenido de proteína cruda fue signifi cativamente mayor con el nitrógeno químico, mientras que el contenido de materia seca fue menor. No se encontraron diferencias signifi cativas entre el tratamiento control y los tratamientos orgánicos.

  11. Comportamento ingestivo de vacas leiteiras alimentadas com dietas à base de cana-de-açúcar ou silagem de milho Ingestive behavior in dairy cows fed sugar cane or corn silage based diets

    Directory of Open Access Journals (Sweden)

    Sandro de Souza Mendonça

    2004-06-01

    Full Text Available Doze vacas da raça Holandesa, puras e mestiças, foram distribuídas em três quadrados latinos 4 X 4, balanceados de acordo com o período de lactação, com o objetivo de avaliar parâmetros do comportamento ingestivo. As dietas experimentais foram à base de silagem de milho com relação volumoso:concentrado de 60:40, com base na matéria seca, ou à base de cana-de-açúcar, com relação volumoso:concentrado de 60:40 ou 50:50. As vacas foram submetidas à observação visual para avaliação do comportamento ingestivo. Os animais foram observados a cada dez minutos, durante 24 horas, para determinação do tempo despendido em alimentação, ruminação e ócio. Não houve diferença para os tempos médios despendidos com alimentação e ruminação entre as dietas experimentais. Entretanto, na dieta à base de silagem de milho, os animais ficaram menos tempo no ócio, quando comparados àqueles alimentados com cana-de-açúcar. Com relação à eficiência de alimentação, expressa em gFDN/h, não houve diferença entre as dietas experimentais. A eficiência de ruminação, expressa em gMS/h, foi semelhante para as diferentes dietas. A eficiência de ruminação, expressa em gFDN/h (ERU FDN foi maior para a dieta à base de silagem de milho. Não houve diferença na ERU FDN entre dietas à base de cana-de-açúcar. Vacas alimentadas com dietas à base de cana-de-açúcar apresentaram maior tempo despendido em ócio e menor consumo de MS, quando comparadas àquelas alimentadas com dietas à base de silagem de milhoTwelve purebred and crossbred Holstein cows were assigned to three Latin squares 4 X 4, balanced according to the lactating period, to evaluate the ingestive behavior parameters. The experimental diets were based on corn silage with 60:40 forage:concentrate ratio, in dry matter (DM basis, or based on sugar cane with 60:40 or 50:50 forage:concentrate. The cows were submitted to visual observation for ingestive behavior evaluation

  12. Desempenho e qualidade do ovo de codornas japonesas alimentadas com rações contendo sorgo Performance and egg quality of laying Japanese quails fed rations with different sorghum levels

    Directory of Open Access Journals (Sweden)

    Adolpho Marlon Antoniol de Moura

    2010-12-01

    Full Text Available Objetivou-se com este estudo avaliar o desempenho e a qualidade dos ovos de codornas japonesas (Coturnix japonica alimentadas com rações cotendo sorgo de baixo tanino em substituição ao milho. Foram utilizadas 210 codornas japonesas fêmeas com 65 dias de idade, distribuídas em delineamento inteiramente casualizado com cinco rações experimentais (0; 25; 50; 75 e 100% de sorgo em substituição ao milho e seis repetições de sete aves. No experimento, cuja duração foi de 112 dias, não houve efeito significativo dos níveis de sorgo nas rações sobre nenhuma das características de produção. Com aumento dos níveis de sorgo na ração, houve redução linear da cor da gema e do custo da ração. O sorgo de baixo tanino pode substituir totalmente o milho em rações para codornas japonesas em postura.The aim of this study was to evaluate performance and egg quality of Japanese quails (Coturnix japonica fed rations with low-tannin sorghum replacing corn. Two hundred and ten 65-d female Japanese quails were distributed in a complete random design with five experimental rations (0, 25, 50, 75 and 100% replacement of corn by sorghum and six replicates with seven birds. There was no significant effect of sorghum levels in the diets on any of the production characteristics in this experiment, which lasted for 112 days. As the levels of sorghum in the ration increased, yolk color and ration cost were reduced. Low-tannin sorghum can completely replace corn in rations for laying Japanese quails.

  13. Comparativo Do Potencial De Produção De Metano Utilizando Glicerol E Sacarose Como Substrato Orgânico, Em Reatores Operados De Forma Descontínua Alimentada

    Directory of Open Access Journals (Sweden)

    Indianara Cataneo

    2016-10-01

    Full Text Available A crise energética que vem preocupando, não só o Brasil, mas todo o mundo, traz a necessidade da busca por fontes energéticas alternativas, ou seja, energias que causem menos impacto ao meio ambiente. Outro problema enfrentado atualmente é a geração de resíduos e efluentes, que demandam tratamentos e controles adequados. A utilização de biogás como fonte renovável de energia vem se mostrando atrativa, considerando a utilização de resíduos e efluentes como substrato orgânico, com produção energética através de processos de digestão anaeróbia. O objetivo deste trabalho foi comparar o potencial de geração de biogás e metano gerado pelo glicerol, subproduto oriundo de indústrias de fabricação de biodiesel, e sacarose, caracterizada por possuir fácil degradabilidade. Foram testados sistemas de digestão anaeróbia de operação descontínua alimentada em reatores de bancada (19,2L de volume útil. Três situações foram avaliadas, 3, 6 e 9% de matéria orgânica em relação ao volume útil dos reatores. O tempo de detenção hidráulica foi de 15 dias para cada situação proposta. Finalizado os experimentos, verificou-se que o glicerol possui maior potencial para a geração de biogás e metano em relação à sacarose, nas concentrações de alimentação utilizadas.

  14. Characterisation of wood combustion ashes

    DEFF Research Database (Denmark)

    Maresca, Alberto

    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...... 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...

  15. 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.

  16. Developments in the technology for the combustion of water emulsions in Mexican fuel oil; Desarrollos en la tecnologia para la combustion de emulsiones agua en combustoleo mexicano

    Energy Technology Data Exchange (ETDEWEB)

    Diego, Antonio Marin; Martinez Flores, Marco A.; Tamayo Flores, Gustavo; Alarcon Quiroz, Ernesto; Melendez Cervantes, Carlos [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    2001-07-01

    The residual petroleum oil (fuel oil) is the most used fuel in boilers of electrical and industrial power stations. Nevertheless, the use of this fuel can generate diverse problems such as the elevated particle emissions, that affect the boiler efficiency, darken the visibility by the smoke that leaves the chimneys and is emitted to the Environment. In addition, sulfur trioxide is produced, which reacts with the water present in the combustion gases, forming sulfuric acid that, when emitted, also affects the visibility of the plume and can be condensed, originating corrosion and increased accumulation of deposits in the boilers. The experimental research was made in a comparative base, between combustion tests of fuel oil, with emulsions where the water concentration and the size of the drops of this one was varied. A diagram of the supply of fuel and preparation of emulsions in a pilot furnace is shown. The article contains graphs of the effect of the water concentration of the emulsions in the particulate emission. The article contains figures of the cenospheres produced by the fuel oil combustion (500 x) and the ones produced by the combustion with 5% of water (500 x). Also shows graphs of the effect of the water drop size of emulsions in the particulate emission, of the reduction of the sulfur trioxide with soluble magnesium products in the water of emulsions, and of the free particle acidity with neutralizers of water emulsions of soluble magnesium. [Spanish] El aceite residual de petroleo (combustoleo) es el combustible mas utilizado en calderas de centrales electricas e industriales. Sin embargo, el uso de este combustible puede generar diverso problemas como las emisiones elevadas de particulas, que afectan la eficiencia de una caldera, obscurecen la visibilidad pero el humo que sale de las chimeneas y se emiten al medio ambiente. Ademas se produce trioxido de azufre, el cual reacciona con el vapor de agua presente en los gases de combustion, formado acido

  17. 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); Sheppard, E.J. [Tuskeggee Univ., Tuskegee, AL (United States). Dept. of Aerospace Engineering

    1995-12-31

    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. 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. The present study represents a coordinated effort between industry, government and academia to investigate gas turbine combustion dynamics. Specific study areas include development of advanced diagnostics, definition of controlling phenomena, advancement of analytical and numerical modeling capabilities, and assessment of the current status of our ability to apply these tools to practical gas turbine combustors. The present work involves four tasks which address, respectively, (1) the development of a fiber-optic probe for fuel-air ratio measurements, (2) the study of combustion instability using laser-based diagnostics in a high pressure, high temperature flow reactor, (3) the development of analytical and numerical modeling capabilities for describing combustion instability which will be validated against experimental data, and (4) the preparation of a literature survey and establishment of a data base on practical experience with combustion instability.

  18. The atomization and the flame structure in the combustion of residual fuel oils; La atomizacion y estructura de flama en la combustion de combustibles residuales

    Energy Technology Data Exchange (ETDEWEB)

    Bolado Estandia, Ramon [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1986-12-31

    In this article a research on the combustion of heavy residual fuel oils is presented. The type of flames studied were obtained by means of the burning of sprays produced by an atomizer designed and calibrated specially for the research purpose. The flame characteristics that were analyzed are its length, its luminosity, the temperature, the distribution of the droplets size and mainly the burning regime of the droplets in the flame. The experimental techniques that were used for these studies were shadow micro-photography, suction pyrometry and of total radiation, laser diffraction, 35 mm photography, and impact push. The analysis of the experimental results, together with the results of the application of a mathematical model, permitted to establish two parameters, that quantitatively related determine the burning regime of the droplets in a flame of sprays of residual heavy fuel oil. [Espanol] En este articulo se presenta una investigacion sobre la combustion de combustibles residuales pesados. El tipo de flamas estudiadas se obtuvieron mediante el quemado de sprays producidos por un atomizador disenado y calibrado especialmente para el proposito de la investigacion. Las caracteristicas de flama que se analizaron son la longitud, la luminosidad, la temperatura, la distribucion de tamano de gotas y, principalmente, el regimen de quemado de gotas en la flama. Las tecnicas experimentales que se usaron para estos estudios fueron microfotografia de sombras, pirometria de succion y de radiacion total, difraccion laser, fotografia de 35 mm y empuje de impacto. El analisis de resultados experimentales, junto con los resultados de la aplicacion de un modelo matematico, permitio establecer dos parametros, que relacionados cuantitativamente, determinan el regimen de quemado de gotas en una flama de sprays de combustible residual pesado.

  19. The atomization and the flame structure in the combustion of residual fuel oils; La atomizacion y estructura de flama en la combustion de combustibles residuales

    Energy Technology Data Exchange (ETDEWEB)

    Bolado Estandia, Ramon [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1985-12-31

    In this article a research on the combustion of heavy residual fuel oils is presented. The type of flames studied were obtained by means of the burning of sprays produced by an atomizer designed and calibrated specially for the research purpose. The flame characteristics that were analyzed are its length, its luminosity, the temperature, the distribution of the droplets size and mainly the burning regime of the droplets in the flame. The experimental techniques that were used for these studies were shadow micro-photography, suction pyrometry and of total radiation, laser diffraction, 35 mm photography, and impact push. The analysis of the experimental results, together with the results of the application of a mathematical model, permitted to establish two parameters, that quantitatively related determine the burning regime of the droplets in a flame of sprays of residual heavy fuel oil. [Espanol] En este articulo se presenta una investigacion sobre la combustion de combustibles residuales pesados. El tipo de flamas estudiadas se obtuvieron mediante el quemado de sprays producidos por un atomizador disenado y calibrado especialmente para el proposito de la investigacion. Las caracteristicas de flama que se analizaron son la longitud, la luminosidad, la temperatura, la distribucion de tamano de gotas y, principalmente, el regimen de quemado de gotas en la flama. Las tecnicas experimentales que se usaron para estos estudios fueron microfotografia de sombras, pirometria de succion y de radiacion total, difraccion laser, fotografia de 35 mm y empuje de impacto. El analisis de resultados experimentales, junto con los resultados de la aplicacion de un modelo matematico, permitio establecer dos parametros, que relacionados cuantitativamente, determinan el regimen de quemado de gotas en una flama de sprays de combustible residual pesado.

  20. Improvement of fuel combustion technologies

    Energy Technology Data Exchange (ETDEWEB)

    Tumanovskii, A.G.; Babii, V.I.; Enyakin, Y.P.; Kotler, V.R.; Ryabov, G.V.; Verbovetskii, E.K.; Nadyrov, I.I. [All-Russian Thermal Engineering Institute, Moscow (Russian Federation)

    1996-07-01

    The main problems encountered in the further development of fuel combustion technologies at thermal power stations in Russia are considered. Experience is generalized and results are presented on the efficiency with which nitrogen oxide emissions are reduced by means of technological methods when burning natural gas, fuel oil, and coal. The problems that arise in the introduction of new combustion technologies and in using more promising grades of coal are considered. The results studies are presented that show that low grade Russian coals can be burnt in circulating fluidized bed boilers. 14 refs., 5 figs., 4 tabs.

  1. 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.

  2. 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

  3. Development of a Premixed Combustion Capability for Scramjet Combustion Experiments

    Science.gov (United States)

    Rockwell, Robert D.; Goyne, Christopher P.; Rice, Brian E.; Chelliah, Harsha; McDaniel, James C.; Edwards, Jack R.; Cantu, Luca M. L.; Gallo, Emanuela C. A.; Cutler, Andrew D.; Danehy, Paul M.

    2015-01-01

    Hypersonic air-breathing engines rely on scramjet combustion processes, which involve high speed, compressible, and highly turbulent flows. The combustion environment and the turbulent flames at the heart of these engines are difficult to simulate and study in the laboratory under well controlled conditions. Typically, wind-tunnel testing is performed that more closely approximates engine testing rather than a careful investigation of the underlying physics that drives the combustion process. The experiments described in this paper, along with companion data sets being developed separately, aim to isolate the chemical kinetic effects from the fuel-air mixing process in a dual-mode scramjet combustion environment. A unique fuel injection approach is taken that produces a nearly uniform fuel-air mixture at the entrance to the combustor. This approach relies on the precombustion shock train upstream of the dual-mode scramjet combustor. A stable ethylene flame anchored on a cavity flameholder with a uniformly mixed combustor inflow has been achieved in these experiments allowing numerous companion studies involving coherent anti-Stokes Raman scattering (CARS), particle image velocimetry (PIV), and planar laser induced fluorescence (PLIF) to be performed.

  4. Analysis regarding steam generator furnace's incident heat, temperature and composition of combustion gases; Analisis de calor incidente, temperatura y composicion de gases de combustion en hornos de generadores de vapor

    Energy Technology Data Exchange (ETDEWEB)

    Diego Marin, Antonio [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2006-07-01

    In order to obtain more precise evaluations of the combustion process in the furnace of a steam generator a suction pyrometer has been integrated to measure the temperature of the combustion gases; an ellipsoidal radiometer to measure the incident heat by thermal radiation in the water walls; a water cooled probe to determine the particle concentration, as well as a water cooled probe to determine the composition of the combustion gases present. This document clarifies the form of use of these instruments and their engineering specifications, simultaneously presenting an analysis that considers, unlike others, the internal conditions of the furnace to obtain a more precise evaluation of the efficiency that the combustion process presents and bases for the taking of preventive actions in specific zones of the furnace. Thus, the present work exhibits instruments and techniques of analysis to study the phenomena occurring within a steam generator. [Spanish] Con el fin de obtener evaluaciones mas precisas del proceso de combustion en el horno de un generador de vapor, se ha integrado un pirometro de succion para medir la temperatura de los gases de combustion; un radiometro elipsoidal para medir el calor incidente por radiacion termica en las paredes del agua; una sonda enfriada con agua para determinar la concentracion de particulas, asi como una sonda refrigerada con agua para determinar la composicion de los gases de combustion presentes. Este documento aclara la forma de uso de estos instrumentos y sus especificaciones tecnicas, a la vez que presenta un analisis que considera, a diferencia de otros, las condiciones internas del horno para obtener una evaluacion mas precisa sobre la eficiencia del proceso de combustion y bases para la toma de acciones preventivas en zonas especificas del horno. Asi, el presente trabajo exhibe instrumentos y tecnicas de analisis para estudiar los fenomenos que ocurren dentro de un generador de vapor.

  5. pacientes con falla cardiaca

    Directory of Open Access Journals (Sweden)

    Diana Marcela Achury Saldaña

    2007-01-01

    Full Text Available Objetivo: determinar la adherencia al tratamiento de pacientes con falla cardiaca hospitalizados, al aplicar un plan educativo quefomenta el autocuidado.Método: estudio cuasiexperimental (entrevistas enfermera-paciente realizado entre diciembre de 2004 y mayo de 2006, con unamuestra de 50 pacientes seleccionados por conveniencia. Se diseñó un instrumento para evaluar los comportamientos de los pacientes,con base en algunos resultados de la adherencia y sus respectivos indicadores de la taxonomía NOC (Nursing out comes classification. Laadherencia al tratamiento fue medida en dos momentos: el primero durante la hospitalización, seguido de la aplicación del plan educativoantes del alta, que proporcionaba información en el manejo de su enfermedad desde una dimensión física, psicológica y social quepromueve el autocuidado; y el segundo un mes después del alta en su domicilio.Resultados: diferencias estadísticamente significativas (P=0,0001 que demuestran cómo mediante la capacitación al paciente enel manejo de su tratamiento farmacológico y no farmacológico, el establecimiento de una sana relación entre el profesional de enfermeríay el paciente, y la participación de la familia, se logra una total adherencia al tratamiento.Conclusiones: para lograr una adherencia total del paciente con falla cardiaca al tratamiento es necesario un proceso educativo y unseguimiento continuo y personalizado que motive permanentemente al paciente y se le reconozca el papel protagónico en su cuidado y manejo de la enfermedad.

  6. Interactive wood combustion for botanical tree models

    KAUST Repository

    Pirk, Sö ren; Jarząbek, Michał; Hadrich, Torsten; Michels, Dominik L.; Palubicki, Wojciech

    2017-01-01

    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

  7. 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.

  8. Method for storing radioactive combustible waste

    Science.gov (United States)

    Godbee, H.W.; Lovelace, R.C.

    1973-10-01

    A method is described for preventing pressure buildup in sealed containers which contain radioactively contaminated combustible waste material by adding an oxide getter material to the container so as to chemically bind sorbed water and combustion product gases. (Official Gazette)

  9. Scramjet Combustion Stability Behavior Modeling, Phase II

    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...

  10. Scramjet Combustion Stability Behavior Modeling, Phase I

    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...

  11. Publication sites productive uses of combustion ash

    Science.gov (United States)

    Publication Sites Productive Uses of Combustion Ash For more information contact: e:mail: Public waste combustion ash in landfills. The new technology brief describes recent studies where ash was used

  12. Combustion Research Facility | A Department of Energy Office of Science

    Science.gov (United States)

    Collaborative Research Facility Back to Sandia National Laboratory Homepage Combustion Research Search the CRF Combustion Chemistry Flame Chemistry Research.Combustion_Chemistry.Flame_Chemistry Theory and Modeling Theory and Modeling Combustion Kinetics High Pressure Chemistry Chemistry of Autoignition

  13. Fuel Combustion and Engine Performance | Transportation Research | NREL

    Science.gov (United States)

    Fuel Combustion and Engine Performance Fuel Combustion and Engine Performance Photo of a gasoline emissions in advanced engine technologies. Photo by Dennis Schroeder, NREL NREL's combustion research and combustion and engine research activities include: Developing experimental and simulation research platforms

  14. Impacto del uso de combustibles alternativos sobre la reactividad del clínker

    OpenAIRE

    Serrano-González, K.; Reyes-Valdez, A.; Chowaniec, O.

    2017-01-01

    El uso de combustibles alternativos en la industria cementera ha ido en incremento en las últimas décadas debido a su beneficio ecológico y económico. En línea con los esfuerzos enfocados en incrementar su uso, se han realizado distintos estudios enfocados en determinar su impacto potencial en la reactividad del clínker y en cómo pueden afectar sus propiedades físicas y mecánicas. Este trabajo estudia el efecto de cinco combustibles alternos sobre la reactividad de ocho muestras industriales ...

  15. 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

  16. 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...

  17. An incinerator for combustable radwastes

    International Nuclear Information System (INIS)

    Li Jingquan; Jiang Yun; Zhang Yinsheng; Chen Boling; Zhang Shihang

    1989-01-01

    An incinerator has been built up in Shanghai. In this paper, the devices of the incinerator, main parameters of the process, and the results of non-radioactive waste and simulated radwaste combustion tests were contributed. That provides reference information for radwaste treatment with incineration process

  18. 75 FR 32142 - Combustible Dust

    Science.gov (United States)

    2010-06-07

    .... Contact Mat Chibbaro, P.E., Fire Protection Engineer, Office of Safety Systems, OSHA Directorate of..., and metals (such as aluminum and magnesium). Industries that may have combustible dust hazards include..., chemical manufacturing, textile manufacturing, furniture manufacturing, metal processing, fabricated metal...

  19. 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...

  20. Multi-zone modelling of PCCI combustion

    NARCIS (Netherlands)

    Egüz, U.; Somers, L.M.T.; Leermakers, C.A.J.; Goey, de L.P.H.

    2011-01-01

    Early Direct Injection Premixed Charge Compression Ignition (EDI PCCI) combustion is a promising concept for the diesel combustion. Although EDI PCCI assures very low soot and NO xemission levels, the injection is uncoupled from combustion, which narrows down the operating conditions. The main

  1. Electrodo biológico con la enzima hidrogenasa, procedimiento de obtención y sus aplicaciones

    OpenAIRE

    Fernández López, Víctor Manuel; López de Lacey, Antonio; Rüdiger Ortiz, Olaf

    2005-01-01

    Electrodo biológico con la enzima hidrogenasa, procedimiento de obtención y sus aplicaciones. En la presente invención se protegen electrodos biológicos modificados con enzimas hidrogenasas (ánodos) mediante los cuales es posible obtener energía eléctrica del hidrógeno en una configuración típica de pilas de combustible; asimismo, con estos electrodos modificados con hidrogenasa (cátodos) es posible producir hidrógeno a partir de agua en una configuración típica de cél...

  2. 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.

  3. 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

  4. Cementos con cenizas volantes

    Directory of Open Access Journals (Sweden)

    Ossa M., Mauricio

    1984-03-01

    additions of 20 and 30% .

    Casi la generalidad de los estudios realizados sobre cementos con adición de cenizas volantes se refieren a sus características y comportamiento en pastas, morteros y hormigones, siempre en relación con aquéllos del cemento portland. Esta vez, se desarrolló un trabajo experimental orientado a relacionar entre sí los cementos con adiciones de cenizas volantes y de puzolana natural. Para ello se fabricaron a escala de laboratorio cementos de ambos tipos, empleando como materias primas comunes clinker y yeso y, como variables, diferentes porcentajes de las dos adiciones, que cumplieron previamente los requisitos normalizados en cuanto a sus actividades puzolánicas. La calidad de los cementos fabricados resultó adecuada y concordante con la del cemento portland-puzolánico obtenido a escala industrial con los mismos clinker, yeso y puzolana natural de este estudio. Posteriormente, se determinaron las características de los cementos experimentales y se confeccionaron morteros normales para la realización de ensayos físicos y mecánicos. Los resultados de ensayos indicaron que los cementos con adición de cenizas volantes (CCV requieren menos agua para consistencia normal, presentan tiempos de fraguado mayores y expansiones en autoclave menores que los cementos con adición de puzolana (CP. Los calores de hidratación a 7 y 28 días de edad fueron aproximadamente similares para ambos tipos de cemento. En morteros normales, los cementos CCV mostraron menor retracción de secado, mayor retentividad y mayor fluidez (para igual cantidad de agua que los cementos CP. En los ensayos de exudación se observó que ésta depende más de la finura que el tipo de adición. Finalmente, los ensayos mecánicos señalaron que las resistencias a compresión y flexotracción de los morteros con cementos CCV son menores a edades inferiores que 14 días (del orden de 5 a 10% a un día de edad, pero que a partir de entonces pasan a ser mayores que las de

  5. Combustor nozzle for a fuel-flexible combustion system

    Science.gov (United States)

    Haynes, Joel Meier [Niskayuna, NY; Mosbacher, David Matthew [Cohoes, NY; Janssen, Jonathan Sebastian [Troy, NY; Iyer, Venkatraman Ananthakrishnan [Mason, OH

    2011-03-22

    A combustor nozzle is provided. The combustor nozzle includes a first fuel system configured to introduce a syngas fuel into a combustion chamber to enable lean premixed combustion within the combustion chamber and a second fuel system configured to introduce the syngas fuel, or a hydrocarbon fuel, or diluents, or combinations thereof into the combustion chamber to enable diffusion combustion within the combustion chamber.

  6. Coal combustion waste management study

    International Nuclear Information System (INIS)

    1993-02-01

    Coal-fired generation accounted for almost 55 percent of the production of electricity in the United States in 1990. Coal combustion generates high volumes of ash and flue gas desulfurization (FGD) wastes, estimated at almost 90 million tons. The amount of ash and flue gas desulfurization wastes generated by coal-fired power plants is expected to increase as a result of future demand growth, and as more plants comply with Title IV of the 1990 Clean Air Act Amendments. Nationwide, on average, over 30 percent of coal combustion wastes is currently recycled for use in various applications; the remaining percentage is ultimately disposed in waste management units. There are a significant number of on-site and off-site waste management units that are utilized by the electric utility industry to store or dispose of coal combustion waste. Table ES-1 summarizes the number of disposal units and estimates of waste contained at these unites by disposal unit operating status (i.e, operating or retired). Further, ICF Resources estimates that up to 120 new or replacement units may need to be constructed to service existing and new coal capacity by the year 2000. The two primary types of waste management units used by the industry are landfills and surface impoundments. Utility wastes have been exempted by Congress from RCRA Subtitle C hazardous waste regulation since 1980. As a result of this exemption, coal combustion wastes are currently being regulated under Subtitle D of RCRA. As provided under Subtitle D, wastes not classified as hazardous under Subtitle C are subject to State regulation. At the same time Congress developed this exemption, also known as the ''Bevill Exclusion,'' it directed EPA to prepare a report on coal combustion wastes and make recommendations on how they should be managed

  7. Modeling of Plasma Assisted Combustion

    Science.gov (United States)

    Akashi, Haruaki

    2012-10-01

    Recently, many experimental study of plasma-assisted combustion has been done. However, numerous complex reactions in combustion of hydrocarbons are preventing from theoritical study for clarifying inside the plasma-assisted combustion, and the effect of plasma-assist is still not understood. Shinohara and Sasaki [1,2] have reported that the shortening of flame length by irradiating microwave without increase of gas temperature. And they also reported that the same phenomena would occur when applying dielectric barrier discharges to the flame using simple hydrocarbon, methane. It is suggested that these phenomena may result by the electron heating. To clarify this phenomena, electron behavior under microwave and DBD was examined. For the first step of DBD plasma-assisted combustion simulation, electron Monte Carlo simulation in methane, oxygen and argon mixture gas(0.05:0.14:0.81) [2] has been done. Electron swarm parameters are sampled and electron energy distribution function (EEDF)s are also determined. In the combustion, gas temperature is higher(>1700K), so reduced electric field E/N becomes relatively high(>10V/cm/Torr). The electrons are accelerated to around 14 eV. This result agree with the optical emission from argon obtained by the experiment of reference [2]. Dissociation frequency of methane and oxygens are obtained in high. This might be one of the effect of plasma-assist. And it is suggested that the electrons should be high enough to dissociate methane, but plasma is not needed.[4pt] [1] K. Shinohara et al, J. Phys. D:Appl. Phys., 42, 182008 (1-7) (2009).[0pt] [2] K. Sasaki, 64th Annual Gaseous Electronic Conference, 56, 15 CT3.00001(2011).

  8. Combustive management of oil spills

    International Nuclear Information System (INIS)

    1992-01-01

    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

  9. Performance of dairy cows fed rations produced with sugarcane silages treated with additives or fresh sugarcane Desempenho de vacas leiteiras alimentadas com rações produzidas com silagens de cana-de-açúcar tratadas com aditivos ou cana-de-açúcar fresca

    Directory of Open Access Journals (Sweden)

    André de Faria Pedroso

    2010-09-01

    Full Text Available An experiment was performed aiming at evaluating the performance of dairy cows fed sugarcane silages treated with additives compared to cows fed fresh forage. Twenty-four Holstein cows were grouped in blocks of three cows, according to parity order and milk production level, in multiple 3 x 3 Latin Square design to evaluate three types of ration (63% roughage and 37% concentrate in dry matter - DM: ration with silage treated with urea (5.0 g/kg of fresh forage - FF + sodium benzoate (0.5 g/kg FF; ration with silage inoculated with Lactobacillus buchneri (5 x 10(4 cfu/g FF; ration with fresh sugarcane. Each evaluation period consisted of two weeks for adaptation and one week for data collection. Cows fed rations with silages treated with urea + benzoate and L. buchneri showed lower DM intake (18.5 vs 21.4 kg/day and lower milk production (17.4 vs 18.6 kg/day in comparison to those fed fresh forage ration. Fat content was higher in the milk of cows fed silage inoculated with L. buchneri compared to cows in the fresh forage group resulting in similar 3.5% fat corrected milk (FCM among cows in both groups. Cows fed ration with silage treated with urea + benzoate presented intermediate fat content in milk but inferior FCM production compared to animals fed fresh sugarcane. Feed efficiency (kg FCM/kg DMI was higher for cows fed ration produced with the inoculated silage (0.95, intermediate for cows that received silage treated with the combination of chemical additives (0.91 and lower for cows fed the ration with fresh sugarcane (0.83.Um experimento foi realizado com o objetivo de avaliar o desempenho de vacas leiteiras alimentadas com silagens de cana-de-açúcar tratadas com aditivos em comparação ao de vacas alimentadas com a forragem fresca. Vinte e quatro vacas holandesas foram agrupadas em blocos de três vacas, de acordo com a ordem do parto e com o nível de produção de leite, em um delineamento quadrado latino múltiplo 3 x 3, para avalia

  10. competencia con China

    Directory of Open Access Journals (Sweden)

    Elena de la Paz Hernández Águila

    2007-01-01

    Full Text Available El artículo ofrece un diagnóstico del desempeño de la industria mexicana del calzado desde la década de los ochenta hasta la actualidad. Analiza la problemática que ha enfrentado esta rama industrial a partir del proceso de apertura comercial y de la competencia en su mercado interno con productos provenientes de países asiáticos, particularmente China. Problematiza al respecto los retos y las perspectivas que a mediano plazo enfrentará este sector empresarial y sobre las posibilidades de competir en el mercado globalizado.

  11. Construir con Madera

    OpenAIRE

    Olabe-Velasco, F. (Fermín); Val-Hernández, Y. (Yolanda); Varela-de-la-Cruz, P. (Perla); Cabrero-Ballarín, J.M. (José Manuel)

    2010-01-01

    Guía divulgativa ‘Construir con madera’, elaborada por la Cátedra Madera de la Universidad de Navarra y el Gobierno de Navarra. La publicación pretende explicar de forma sencilla los beneficios y posibilidades de este material en la construcción, tanto en lo que respecta a su resistencia, comportamiento frente al fuego, durabilidad, capacidad de aislamiento, propiedades acústicas, estética, respeto al medio ambiente y sostenibilidad como fuente de energía. A modo de ejemplo, en la ...

  12. Evaluación del funcionamiento de motores de combustión interna trabajando con biodiesel.

    Directory of Open Access Journals (Sweden)

    R. Piloto Rodríguez

    2008-09-01

    Full Text Available En el presente trabajo se determinó la característica exterior de velocidad para dos motores de combustión interna trabajando con combustible biodiesel procedente de varias fuentes naturales y se comparó con la característica exterior de velocidad de los motores originalmente trabajando con combustible diesel. Los motores fueron evaluados con variaciones de carga y velocidad. En uno de los motores ensayados fue determinada la presión en el interior de la cámara de combustión con el objetivo de evaluar el retardo de ignición. Fue observado que los motores trabajando con combustible biodiesel presentaban una disminución de la potencia efectiva y un aumento del consumo especifico de combustible. Se observó una disminución del retardo de ignición cuando fue empleado el combustible biodiesel. También fue observado que los gases contaminantes, excepto las emisiones de NOx y CO, disminuyen o permanecen constantes con el uso del biocombustible. The engine outer velocity characterization for two engines was made working with biodiesel from different natural sources, and its performance was compared with the engine parameters using reference diesel. The engines were used varying load and velocity. The ignition delay was obtained by measurement of in-cylinder pressure. A decrease in the effective power and increase in the effective fuel consumption were observed in the engines when biodiesel is used. Biodiesel samples shown shorter ignition delay than diesel. The pollutants emitted for the engine using biodiesel was lower than diesel, with the exception of NOx and CO emissions.

  13. Use of combustible wastes as fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kotler, V.R.; Salamov, A.A.

    1983-01-01

    Achievements of science and technology in creating and using units for combustion of wastes with recovery of heat of the escaping gases has been systematized and generalized. Scales and outlooks are examined for the use of general, industrial and agricultural waste as fuel, composition of the waste, questions of planning and operating units for combustion of solid refuse, settling of waste water and industrial and agricultural waste. Questions are covered for preparing them for combustion use in special units with recovery of heat and at ES, aspects of environmental protection during combustion of waste, cost indicators of the employed methods of recovering the combustible waste.

  14. Distributed Low Temperature Combustion: Fundamental Understanding of Combustion Regime Transitions

    Science.gov (United States)

    2016-09-07

    behaviour as compared to ethanol. The latter fuel has also been considered along with methane. Work has also been performed on the further assessment of... behaviour as compared to ethanol. The latter fuel has also been considered along with methane. Work has also been performed on the further assess- ment of...identification of various combustion gas states. A range of Damköhler numbers (Da) from the conventional propagating flamelet regime well into the distributed

  15. Entrevista con Giovanni Levi

    Directory of Open Access Journals (Sweden)

    Monica Oliveira

    2017-06-01

    Full Text Available En esta entrevista, Giovanni Levi - como un conocedor del tema de Familia - realiza una importante evaluación sobre el actual estado de las investigaciones realizadas en el Brasil y em el exterior. Con estilo franco, agudo y lucido critica las visiones tradicionales y sus ilusiones ypropone nuevos conceptos y métodos. La historia de la familia debería ceder espacio para el estudio de las redes relacionales o de los mundos relacionales. De la misma forma, la historia cuantitativa debería abrir espacio para el estudio de las cualidades. Ya con relación a la historia de las elites, tan estudiada y reproducida en una diversidad de trabajos, que deberíase mirar en otra perspectiva. Es decir, no mirar a las reglas sociales predeterminadas, sino a los desvíos y a las variaciones. Levi defiende que los historiadores deben trascender a los documentos que se encuentran fácilmente y que pueden fortalecer perspectivas deformadas y esequilibradas de la sociedad. Para él, los historiadores deben esforzarse por estudiar a aquellos grupos que dejaron pocos rastros documentales. En ese esfuerzo existiría una nueva mirada sobre la historia de la familia.

  16. Entrevista con Patricia Ariza

    Directory of Open Access Journals (Sweden)

    Esperanza Londoño La Rotta

    2017-01-01

    Full Text Available Pensamiento, Palabra y Obra entrevista a una artista, feminista y activista política, quien como mujer y artista ha permitido pensar el arte más allá de un simple espectáculo. Toda una vida dedicada al teatro y a darle voz, a través de sus obras, a víctimas del conflicto colombiano, defensora de derechos humanos; además de hacer evidente en su vida y a través de la plataforma “Artistas por la paz”, las múltiples relaciones que se pueden establecer entre el arte, la construcción de paz y la resolución de conflictos. Hablamos en su casa, en medio del calor de la bienvenida con Patricia Ariza, directora del festival alternativo de teatro, de Mujeres en Escena y de la Corporación Colombiana de Teatro, entre otras muchas actividades que voluntariamente su espíritu libertario ha asumido. Esta entrevista se realizó antes del 2 de octubre, pero con la revisión de los acuerdos que propició el plebiscito ganado por una ínfima minoría por el no, sigue siendo vigente este planteamiento.

  17. Molten salt combustion of radioactive wastes

    International Nuclear Information System (INIS)

    Grantham, L.F.; McKenzie, D.E.; Richards, W.L.; Oldenkamp, R.D.

    1976-01-01

    The Atomics International Molten Salt Combustion Process reduces the weight and volume of combustible β-γ contaminated transuranic waste by utilizing air in a molten salt medium to combust organic materials, to trap particulates, and to react chemically with any acidic gases produced during combustion. Typically, incomplete combustion products such as hydrocarbons and carbon monoxide are below detection limits (i.e., 3 ) is directly related to the sodium chloride vapor pressure of the melt; >80% of the particulate is sodium chloride. Essentially all metal oxides (combustion ash) are retained in the melt, e.g., >99.9% of the plutonium, >99.6% of the europium, and >99.9% of the ruthenium are retained in the melt. Both bench-scale radioactive and pilot scale (50 kg/hr) nonradioactive combustion tests have been completed with essentially the same results. Design of three combustors for industrial applications are underway

  18. Produção e qualidade do leite de vacas da raça Holandesa alimentadas com silagens de grama estrela (Cynodon nlemfuensis Vanderyst = Production and quality of milk from Holstein cows fed stargrass silages (Cynodon nlemfuensis Vanderyst

    Directory of Open Access Journals (Sweden)

    Valter Harry Bumbieris Junior

    2007-01-01

    Full Text Available Objetivou-se avaliar o desempenho e a qualidade do leite produzido por vacas da raça Holandesa no terço final da lactação, alimentadas com silagens de grama estrela com aplicação de inoculante ou uréia em relação à silagem de milho. Foram avaliadas silagens de grama estrela com aplicação de aditivo enzimo-bacteriano na dosagem de 80 g deinoculante/tonelada, uréia na dosagem de 7 kg t-1 e silagem de milho. Para avaliação do desempenho produtivo e digestibilidade foram utilizadas seis vacas da raça Holandesas com peso médio de 480 kg distribuídas em delineamento (duplo quadrado latino (3 x 3. Asdigestibilidades da MS, PB e FDN foram maiores para a silagem de milho. O fornecimento de silagens de grama estrela com aditivo e com uréia não interferiu na produção e qualidade do leite, mostrando-se como alternativa para sistemas de produção animal com base emvolumosos conservados mediante a análise econômica da substituição da silagem de milho.The study aimed to evaluate animal performance and quality of milk from Holstein cows during the final third period of lactation fed stargrass silages supplied with inoculant or urea in relation to corn silage. Stargrass silages with enzymatic-bacterial inoculant (80 g of additive/ton of silage, urea supply (7 kg t-1 and corn silage were evaluated. Six Holstein cows with an average body weight of 480 kg were allocated in a double Latin square design (3 x 3. Corn silagepresented the highest values of DM, CP and NDF digestibility when compared to stargrass silages. Supplying Holstein cows with stargrass silages with additive and urea did not promote any effect on production and milk quality. Thus, it can be an alternative in animalproduction systems based on conserved roughage, depending on economical analysis for the replacement of corn silage.

  19. Desempenho produtivo de tilápia do Nilo alimentada com níveis de colina na dieta = Growth performance of Nile tilapia fed graded choline levels in the diet

    Directory of Open Access Journals (Sweden)

    Ademir Calvo Fernandes Junior

    2010-04-01

    Full Text Available Este estudo foi realizado com o objetivo de avaliar o desempenho produtivo da tilápia do Nilo (Oreochromis niloticus alimentada com níveis de colina na dieta pelo período de 109 dias. Foram utilizados 192 alevinos com 4,0 ± 0,15 g de peso médio, distribuídos em 32 tanques-rede de 200 L, na densidade de seis peixes por tanque-rede, dispostos em aquários de 1.000 L. O delineamento experimental foi inteiramente casualizado com oito tratamentos e quatro repetições. As rações foram suplementadas com 0, 100, 200, 400, 600, 800, 1.000 e 1.200 mg de colina kg-1 de ração. Não foram observadas diferenças para ganho de peso, taxa de sobrevivência, conversão alimentar aparente, porcentagem de extrato etéreo do filé e do fígado, índice hepatossomático e concentração de lipídeos no plasma. Concluiuseque os diferentes níveis de colina não melhoraram o desempenho produtivo dos peixes nestas condições, pois a dieta basal supostamente supriu a exigência do peixe para colina.A 109-day feeding trial was undertaken aiming to evaluate the growth performance of Nile tilapia fed graded choline levels. One hundred and ninety-two (initial weight 4.0 ± 0.15 g fingerlings were distributed into 32 net cages (200 L each, four cages per treatmentand six fish per cage, placed in eight 1000L aquaria in a closed recirculation system. The treatments were assigned to the tanks comprising eight treatments and four replications arranged in a completely randomized experimental design. Diets were supplemented with choline chloride to provide 100, 200, 400, 600, 800, 1000, 1200 mg of choline per kg of feed and an unsupplemented diet. No significant differences were observed in growth performance, survival, apparent feed conversion, liver and fillet ether extract, hepatosomatic index and plasma lipid concentration, among treatments. Choline levels did not improve growth performance, possibly because the amount of choline in the diet had already met fish

  20. 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

  1. 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...

  2. Combustion process science and technology

    Science.gov (United States)

    Hale, Robert R.

    1989-01-01

    An important and substantial area of technical work in which noncontact temperature measurement (NCTM) is desired is that involving combustion process research. In the planning for this workshop, it was hoped that W. Serignano would provide a briefing regarding the experimental requirements for thermal measurements to support such research. The particular features of thermal measurement requirements included those describing the timeline for combustion experiments, the requirements for thermal control and diagnostics of temperature and other related thermal measurements and the criticality to the involved science to parametric features of measurement capability including precision, repeatability, stability, and resolution. In addition, it was hoped that definitions could be provided which characterize the needs for concurrent imaging as it relates to science observations during the conduct of experimentation.

  3. Dynamical issues in combustion theory

    International Nuclear Information System (INIS)

    Fife, P.C.; Williams, F.

    1991-01-01

    This book looks at the world of combustion phenomena covering the following topics: modeling, which involves the elucidation of the essential features of a given phenomenon through physical insight and knowledge of experimental results, devising appropriate asymptotic and computational methods, and developing sound mathematical theories. Papers in this book describe how all of these challenges have been met for particular examples within a number of common combustion scenarios: reactive shocks, low Mach number premixed reactive flow, nonpremixed phenomena, and solid propellants. The types of phenomena examined are also diverse: the stability and other properties of steady structures, the long time dynamics of evolving solutions, properties of interfaces and shocks, including curvature effects, and spatio-temporal patterns

  4. SPECIFIC EMISSIONS FROM BIOMASS COMBUSTION

    Directory of Open Access Journals (Sweden)

    Pavel Skopec

    2014-02-01

    Full Text Available This paper deals with determining the specific emissions from the combustion of two kinds of biomass fuels in a small-scale boiler. The tested fuels were pellets made of wood and pellets made of rape plant straw. In order to evaluate the specific emissions, several combustion experiments were carried out using a commercial 25 kW pellet-fired boiler. The specific emissions of CO, SO2 and NOx were evaluated in relation to a unit of burned fuel, a unit of calorific value and a unit of produced heat. The specific emissions were compared with some data acquired from the reference literature, with relatively different results. The differences depend mainly on the procedure used for determining the values, and references provide no information about this. Although some of our experimental results may fit with one of the reference sources, they do not fit with the other. The reliability of the references is therefore disputable.

  5. Steady state HNG combustion modeling

    Energy Technology Data Exchange (ETDEWEB)

    Louwers, J.; Gadiot, G.M.H.J.L. [TNO Prins Maurits Lab., Rijswijk (Netherlands); Brewster, M.Q. [Univ. of Illinois, Urbana, IL (United States); Son, S.F. [Los Alamos National Lab., NM (United States); Parr, T.; Hanson-Parr, D. [Naval Air Warfare Center, China Lake, CA (United States)

    1998-04-01

    Two simplified modeling approaches are used to model the combustion of Hydrazinium Nitroformate (HNF, N{sub 2}H{sub 5}-C(NO{sub 2}){sub 3}). The condensed phase is treated by high activation energy asymptotics. The gas phase is treated by two limit cases: the classical high activation energy, and the recently introduced low activation energy approach. This results in simplification of the gas phase energy equation, making an (approximate) analytical solution possible. The results of both models are compared with experimental results of HNF combustion. It is shown that the low activation energy approach yields better agreement with experimental observations (e.g. regression rate and temperature sensitivity), than the high activation energy approach.

  6. 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.

  7. Coal combustion technology in China

    International Nuclear Information System (INIS)

    Huang, Z.X.

    1994-01-01

    Coal is the most important energy source in China, the environmental pollution problem derived from coal burning is rather serious in China. The present author discusses coal burning technologies both in boilers and industrial furnaces and their relations with environmental protection problems in China. The technological situations of Circulating Fluidized Bed Coal Combustor, Pulverized Coal Combustor with Aerodynamic Flame Holder and Coal Water Slurry Combustion have been discussed here as some of the interesting problems in China only. (author). 3 refs

  8. Example Problems in LES Combustion

    Science.gov (United States)

    2016-09-26

    Lesieur, M., Turbulence in Fluids , 2nd Revised Ed., Fluid Mechanics and Its Applications, Vol. 1, Kluwer Academic Publishers, Boston, Massachusetts, 1990...34, Journal of Fluid Mechanics , Vol. 238, 1992, pp. 155-185. 5. Hirsch, C., Numerical Computation of Internal and External Flows, Vol. 2, Computational...reaction mechanisms for the oxidation of hydrocarbon fuels in flames", Combustion Science and Technology, Vol. 27, 1981, pp. 31-43. 14. Spalding, D.B

  9. 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.

  10. Combustion char characterisation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, P; Ingermann Petersen, H; Sund Soerensen, H; Thomsen, E; Guvad, C

    1996-06-01

    The aim was to correlate reactivity measures of raw coals and the maceral concentrates of the coals obtained in a previous project with the morphology of the produced chars by using a wire grid devolatilization method. Work involved determination of morphology, macroporosity and a detailed study by Scanning Electron Microscopy (SEM). Systematic variations in the texture of chars produced in different temperature domains and heating rates were demonstrated by using incident light microscopy on polished blocks and by SEM studies directly on the surfaces of untreated particles. Results suggest that work in the field of char reactivity estimates and correlations between char morphology and coal petrography can be accomplished only on chars produced under heating rates and temperatures comparable to those for the intended use of coal. A general correlation between the coals` petrography and the the morphology of high temperature chars was found. The SEM study of the chars revealed that during the devolatilization period the particles fuse and the macroporosity and thus the morphotypes are formed. After devolatilization ceases, secondary micropores are formed. These develop in number and size throughout the medium combustion interval. At the end of the combustion interval the macrostructure breaks down, caused by coalescence of the increased number of microspores. This can be observed as a change in the morphology and the macroporosity of the chars. Results indicate that char reactivity is a function of the macroporosity and thus the morphology of combustion chars. (AB) 34 refs.

  11. Management of coal combustion wastes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-02-01

    It has been estimated that 780 Mt of coal combustion products (CCPs) were produced worldwide in 2010. Only about 53.5% were utilised, the rest went to storage or disposal sites. Disposal of coal combustion waste (CCW) on-site at a power plant may involve decades-long accumulation of waste, with hundreds of thousands, if not millions, of tonnes of dry ash or wet ash slurry being stored. In December 2008, a coal combustion waste pond in Kingston, Tennessee, USA burst. Over 4 million cubic metres of ash sludge poured out, burying houses and rivers in tonnes of toxic waste. Clean-up is expected to continue into 2014 and will cost $1.2 billion. The incident drew worldwide attention to the risk of CCW disposal. This caused a number of countries to review CCW management methods and regulations. The report begins by outlining the physical and chemical characteristics of the different type of ashes generated in a coal-fired power plant. The amounts of CCPs produced and regulations on CCW management in selected countries have been compiled. The CCW disposal methods are then discussed. Finally, the potential environmental impacts and human health risks of CCW disposal, together with the methods used to prevent them, are reviewed.

  12. 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.

  13. Design and construction of a new furnace combustion pilot in IIE; Diseno y construccion de un nuevo horno experimental de combustion en el IIE

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Flores, Marco Antonio; Tamayo Flores, G. A. [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: mamf@iie.org.mx; gatamayo@iie.org.mx

    2010-11-15

    To expand the scope of studies and technological developments in the Laboratory of Combustion of the Thermal Process Management a new experimental furnace with a capacity of 1.5 MWt was designed and built. Spray design studies with real operational evaluation (comparison of emission of Combustion products and thermal behavior) as well as information on the behavior of the NO{sub x} emissions will be produced. An automatic control system using a water cooling jacket provides the cooling of the furnace. The furnace design is modular, consisting of six sections. Currently three trials to its maximum load of operation have been performed. The results show that the global energy balance of the furnace matches the design. The flue gas residence time and temperature also match those at the exit of steam generators of big capacity. [Spanish] Para ampliar las posibilidades de estudios y desarrollos tecnologicos del laboratorio de combustion de la Gerencia de Procesos Termicos, se diseno y construyo un nuevo horno experimental con capacidad maxima de 1.5 MegaWatts termicos (MWt). Este horno permitira realizar estudios de diseno de atomizadores con evaluacion de operacion real (comparacion de emision de productos de combustion y comportamiento termico), asi como ampliar la informacion que se tiene en el comportamiento de la emision de los oxidos de nitrogeno (NO{sub x}) que se producen en el horno. El diseno del horno es modular, compuesto por seis secciones, las cuales se enfrian de forma independiente a traves de un sistema de control automatico, empleando una chaqueta de enfriamiento por la cual circula agua. Actualmente se han realizado tres encendidos hasta alcanzar su carga maxima de operacion, los resultados obtenidos muestran que el balance de energia global del horno experimental es practicamente el de diseno y cumple con las caracteristicas de tiempo de residencia y temperatura de gases a la salida del horno de Generadores de Vapor de gran capacidad.

  14. LES of explosions in venting chamber: A test case for premixed turbulent combustion models

    OpenAIRE

    Vermorel , Olivier; Quillatre , Pierre; Poinsot , Thierry

    2017-01-01

    International audience; This paper presents a new experimental and Large Eddy Simulation (LES) database to study upscaling effects in vented gas explosions. The propagation of premixed flames in three setups of increasing size is investigated experimentally and numerically. The baseline model is the well-known laboratory-scale combustion chamber from Sydney (Kent et al., 2005; Masri et al., 2012); two exact replicas at scales 6 and 24.4 were set up by GexCon (Bergen, Norway). The volume ratio...

  15. 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.

  16. 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

  17. preescolares desnutridos con madres con obesidad y sin obesidad

    Directory of Open Access Journals (Sweden)

    Viridiana Vanessa Conzuelo-González

    2009-01-01

    Full Text Available El primer objetivo fue conocer cuántos menores de cinco años con diferentes grados de desnutrición tienen una madre con sobrepeso/obesidad/ en una comunidad indígena que vive en extrema pobreza y bajo condiciones de migración masculina internacional. El segundo fue comparar tres variables socionutricionales (ingreso familiar, educación de la madre y adecuación nutrimental de la dieta diaria entre estos hogares y los hogares con desnutrición infantil y madres sin obesidad. Se realizó un estudio transversal (2006-2007, en la comunidad mazahua de San Francisco Tepeolulco, Municipio de Temascalcingo; que incluyó a 85 hogares integrados por preescolares con desnutrición inscritos al programa Oportunidades. Se determinó el estado nutrición de los preescolares con indicadores antropométricos y se obtuvo el IMC de las madres de estos infantes. Se aplicó una encuesta socionutricional, incluida el recordatorio de 24 horas, y complementado con la observación participante (cualitativa. Se encontró que 83% de las madres mazahuas presentaron sobrepeso u obesidad. El estado de nutrición de los preescolares con madres con obesidad presentó un porcentaje mayor de desnutrición (76%. En la variable género, se encontró que 54% de los niños con madres con obesidad tenía baja talla. Al relacionar el nivel educativo de la madre, esta variable resultó ser estadísticamente significativa (p=0.015, donde el analfabetismo está más relacionado con la desnutrición infantil que tienen madres de bajo y/o peso normal. La elevada prevalencia de hogares conformados con preescolares con desnutrición y madres con obesidad, es un síntoma más de la pobreza en zonas indígenas en México, con bajo índice de desarrollo humano.

  18. IEA combustion agreement : a collaborative task on alternative fuels in combustion

    International Nuclear Information System (INIS)

    Larmi, M.

    2009-01-01

    The focus of the alternative fuels in combustion task of the International Energy Agency is on high efficiency engine combustion, furnace combustion, and combustion chemistry. The objectives of the task are to develop optimum combustion for dedicated fuels by fully utilizing the physical and chemical properties of synthetic and renewable fuels; a significant reduction in carbon dioxide, NOx and particulate matter emissions; determine the minimum emission levels for dedicated fuels; and meet future emission standards of engines without or with minimum after-treatment. This presentation discussed the alternative fuels task and addressed issues such as synthetic fuel properties and benefits. The anticipated future roadmap was presented along with a list of the synthetic and renewable engine fuels to be studied, such as neat oxygenates like alcohols and ethers, biogas/methane and gas combustion, fuel blends, dual fuel combustion, high cetane number diesel fuels like synthetic Fischer-Tropsch diesel fuel and hydrogenated vegetable oil, and low CN number fuels. Implementation examples were also discussed, such as fuel spray studies in optical spray bombs; combustion research in optical engines and combustion chambers; studies on reaction kinetics of combustion and emission formation; studies on fuel properties and ignition behaviour; combustion studies on research engines; combustion optimization; implementing the optimum combustion in research engines; and emission measurements. Overall milestone examples and the overall schedule of participating countries were also presented. figs.

  19. Catalizadores anodicos basados en platino para celdas de combustible de etanol

    Directory of Open Access Journals (Sweden)

    BIBIAN HOYOS

    2007-01-01

    Full Text Available Se estudió el comportamiento electro catalítico de platino puro y aleaciones basadas en él con Ru, Sn, Ir y Os soportados en carbón para la electro oxidación de etanol con el propósito de desarrollar catalizadores anódicos para celdas de combustible directas de etanol. Adicionalmente, se construyeron electrodos porosos y ensambles electrodo-membrana para celdas de combustible poliméricas, en las cuales se probaron los ánodos. La caracterización de los catalizadores se realizó mediante voltametría cíclica, mientras que las pruebas del desempeño de las celdas se realizaron mediante pruebas de polarización corriente-potencial. En general, todas las aleaciones mostraron un menor potencial de inicio de la reacción y mayor actividad catalítica que el platino puro. Sin embargo en la zona de altos sobre potenciales, el platino puro tiene mayor actividad catalítica que las aleaciones. De acuerdo con estos resultados, las aleaciones estudiadas podrían ser útiles en celdas de combustible operando a corrientes moderadas y bajas

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

    Science.gov (United States)

    1991-07-01

    the of ether and ethyl alcohol and removing objective of these lectures to give a this solvent. Instead of having a fibrous comprehensive understanding...do cetto esrne do Les propergols composites, A matrice confifrences une description tout A fait A polymarique charg~o pst, un oxydant at un jour des...rusa., De nouveaux souvant suppos6 qua la vitesa des gaz de oxydes de for ultrafirts mont aujourd’hui combustion est n~gligeable at qua d~velopps pour

  1. 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......-column’’ approach and includes the energy equations for both the fuel and the gas accounting for heat transfer between the two phases. The model gives important insight into the combustion process and provides inlet conditions for a computational fluid dynamics analysis of the freeboard. The model predictions...... indicate the existence of two distinct combustion modes. Combustion air temperature and mass flow-rate are the two parameters determining the mode. There is a significant difference in reaction rates (ignition velocity) and temperature levels between the two modes. Model predictions were compared...

  2. 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...

  3. Utilización de la proteína dietaría por alevinos de la gamitana, Colossoma macropomum, alimentados con dietas isocalóricas

    Directory of Open Access Journals (Sweden)

    Félix Walter Gutiérrez

    2011-05-01

    Full Text Available Un experimento fue conducido para evaluar los efectos de cinco niveles de proteína (25,27, 29, 31 y 33% sobre el comportamiento productivo de alevinos de la gamitana, Colossoma macropomum Cuvier 1818, alimentados con dietas isocalóricas (2,7 kcal de ED/g. Los parámetros medidos fueron ganancia de peso (GP, conversión alimenticia (CA, proteína retenida (PR, razón de eficiencia proteica (REP y energía retenida (ER. En la preparación de las dietas experimentales se utilizaron como fuentes de proteína harina de anchoveta y harina de torta de soya y como fuentes de energía maíz amarillo duro, subproducto de trigo y aceite de pescado. Se encontraron diferencias significativas (P<0,05 entre tratamientos para los parámetros GP, PR, REP y ER. No se encontraron diferencias significativas para la CA. Los mejores rendimientos fueron obtenidos cuando las gamitanas fueron alimentadas con niveles dietarios de 25, 27 y 33% de proteína cruda. También se encontró que a medida que se elevó el nivel de proteína de la dieta, la REP decreció significativamente. Tomando en cuenta el costo de la proteína en la dieta, se concluye que la alimentación de la gamitana con niveles dietarios de 25 ó 27% de proteína cruda y 2,7 kcal de ED/g, garantizarán su exitoso crecimiento.

  4. Numerical investigation of biogas flameless combustion

    International Nuclear Information System (INIS)

    Hosseini, Seyed Ehsan; Bagheri, Ghobad; Wahid, Mazlan Abdul

    2014-01-01

    Highlights: • Fuel consumption decreases from 3.24 g/s in biogas conventional combustion to 1.07 g/s in flameless mode. • The differences between reactants and products temperature intensifies irreversibility in traditional combustion. • The temperature inside the chamber is uniform in biogas flameless mode and exergy loss decreases in this technique. • Low O 2 concentration in the flameless mode confirms a complete and quick combustion process in flameless regime. - Abstract: The purpose of this investigation is to analyze combustion characteristics of biogas flameless mode based on clean technology development strategies. A three dimensional (3D) computational fluid dynamic (CFD) study has been performed to illustrate various priorities of biogas flameless combustion compared to the conventional mode. The effects of preheated temperature and wall temperature, reaction zone and pollutant formation are observed and the impacts of combustion and turbulence models on numerical results are discussed. Although preheated conventional combustion could be effective in terms of fuel consumption reduction, NO x formation increases. It has been found that biogas is not eligible to be applied in furnace heat up due to its low calorific value (LCV) and it is necessary to utilize a high calorific value fuel to preheat the furnace. The required enthalpy for biogas auto-ignition temperature is supplied by enthalpy of preheated oxidizer. In biogas flameless combustion, the mean temperature of the furnace is lower than traditional combustion throughout the chamber. Compared to the biogas flameless combustion with uniform temperature, very high and fluctuated temperatures are recorded in conventional combustion. Since high entropy generation intensifies irreversibility, exergy loss is higher in biogas conventional combustion compared to the biogas flameless regime. Entropy generation minimization in flameless mode is attributed to the uniform temperature inside the chamber

  5. 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

  6. autorregulado con estudiantes universitarios

    Directory of Open Access Journals (Sweden)

    Jairo Andrés Montes

    2005-01-01

    Full Text Available El propósito del presente estudio es describir la forma en la que se presentan los procesos de aprendizaje autorregulado con un grupo de estudiantes (22 estudiantes de tercer semestre de Psicología de la PUJ, Cali, en el evento de preparación para la presentación un examen. Asimismo se describen las correlaciones que ocurren entre las distintas fases de dicho proceso de autorregulación del aprendizaje. Para conseguir los objetivos propuestos se ha hecho uso de una observación de desempeño en tiempo real, es decir, de la observación durante una sesión de preparación de examen de los estudiantes, en la cual se emplearon protocolos verbales para dar cuenta de lo que «pasaba por su mente» mientras estudiaban. Una entrevista semi-estructurada y una prueba objetiva. Los resultados fueron analizados a la luz del modelo mixto de procesamiento de información y constructivismo abordado por Winne(1998. Como resultado se encontró una relación significativa entre los niveles de desempeño en el proceso de ARR y el resultado del examen. Igualmente se encontraron bajos niveles de regulación en una parte importante de la muestra y un desfase significativo entre conocimiento declarativo de ARR y desempeño en el mismo

  7. Turbine Burners: Turbulent Combustion of Liquid Fuels

    National Research Council Canada - National Science Library

    Sirignano, William A; Liu, Feng; Dunn-Rankin, Derek

    2006-01-01

    The proposed theoretical/computational and experimental study addresses the vital two-way coupling between combustion processes and fluid dynamic phenomena associated with schemes for burning liquid...

  8. Pressurized Fluidized Bed Combustion of Sewage Sludge

    Science.gov (United States)

    Suzuki, Yoshizo; Nojima, Tomoyuki; Kakuta, Akihiko; Moritomi, Hiroshi

    A conceptual design of an energy recovering system from sewage sludge was proposed. This system consists of a pressurized fluidized bed combustor, a gas turbine, and a heat exchanger for preheating of combustion air. Thermal efficiency was estimated roughly as 10-25%. In order to know the combustion characteristics of the sewage sludge under the elevated pressure condition, combustion tests of the dry and wet sewage sludge were carried out by using laboratory scale pressurized fluidized bed combustors. Combustibility of the sewage sludge was good enough and almost complete combustion was achieved in the combustion of the actual wet sludge. CO emission and NOx emission were marvelously low especially during the combustion of wet sewage sludge regardless of high volatile and nitrogen content of the sewage sludge. However, nitrous oxide (N2O) emission was very high. Hence, almost all nitrogen oxides were emitted as the form of N2O. From these combustion tests, we judged combustion of the sewage sludge with the pressurized fluidized bed combustor is suitable, and the conceptual design of the power generation system is available.

  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. 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.

  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. Modeling nitrogen chemistry in combustion

    DEFF Research Database (Denmark)

    Glarborg, Peter; Miller, James A.; Ruscic, Branko

    2018-01-01

    the accuracy of engineering calculations and thereby the potential of primary measures for NOx control. In this review our current understanding of the mechanisms that are responsible for combustion-generated nitrogen-containing air pollutants is discussed. The thermochemistry of the relevant nitrogen...... via NNH or N2O are discussed, along with the chemistry of NO removal processes such as reburning and Selective Non-Catalytic Reduction of NO. Each subset of the mechanism is evaluated against experimental data and the accuracy of modeling predictions is discussed....

  13. Experimental validation for combustion analysis of GOTHIC code in 2-dimensional combustion chamber

    International Nuclear Information System (INIS)

    Lee, J. W.; Yang, S. Y.; Park, K. C.; Jung, S. H.

    2002-01-01

    In this study, the prediction capability of GOTHIC code for hydrogen combustion phenomena was validated with the results of two-dimensional premixed hydrogen combustion experiment executed by Seoul National University. The experimental chamber has about 24 liter free volume (1x0.024x1 m 3 ) and 2-dimensional rectangular shape. The test were preformed with 10% hydrogen/air gas mixture and conducted with combination of two igniter positions (top center, top corner) and two boundary conditions (bottom full open, bottom right half open). Using the lumped parameter and mechanistic combustion model in GOTHIC code, the SNU experiments were simulated under the same conditions. The GOTHIC code prediction of the hydrogen combustion phenomena did not compare well with the experimental results. In case of lumped parameter simulation, the combustion time was predicted appropriately. But any other local information related combustion phenomena could not be obtained. In case of mechanistic combustion analysis, the physical combustion phenomena of gas mixture were not matched experimental ones. In boundary open cases, the GOTHIC predicted very long combustion time and the flame front propagation could not simulate appropriately. Though GOTHIC showed flame propagation phenomenon in adiabatic calculation, the induction time of combustion was still very long compare with experimental results. Also, it was found that the combustion model of GOTHIC code had some weak points in low concentration of hydrogen combustion simulation

  14. Engine combustion network (Ecn) : characterization and comparison of boundary conditions for different combustion vessels

    NARCIS (Netherlands)

    Meijer, M.; Somers, L.M.T.; Johnson, J.; Naber, J.; Lee, S.Y.; Malbec, L.M.; Bruneaux, G.; Pickett, L.M.; Bardi, M.; Payri, R.; Bazyn, T.

    2012-01-01

    The Engine Combustion Network (ECN) is a worldwide group of institutions using combustion vessels and/or performing computational fluid dynamics (CFD) simulation, whose aim is to advance the state of spray and combustion knowledge at engine-relevant conditions. A key activity is the use of spray

  15. Puentes con vigas pretensadas

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1965-07-01

    Full Text Available This paper describes one of the three bridges which Hidrocivil, S. A., has built in Catalonia (northern Spain, over the river Ripoll. The other two bridges are very similar to this one, both in construction and design, and show only minor adjustments to the local topography. The contracting firm proposed several alterations in the prefabrication and constructional procedure, in relation to the initial project, and these changes were accepted. The main feature of these projects is the use of prestressed beams, built at the workshop in sections, and joined together by means of sixty 7 mm cables in each beam. As the shear forces are more acute at the joints, the end of each section has a kind of diaphragm, to provide a large contact area, and hence greater surface to transmit the shear forces. The methods of construction are also of interest. Briefly, they involve building the bridge piles, and use these to support a provisional structure with transversal movement. This provisional structure, in turn, served as platform for two bridge cranes, which lifted the girders to their final location. After the first span was completed, the deck was concreted and the auxiliary structure pushed forward to the next span, to repeat the same operations. This arrangement saved the use of provisional framework.En este trabajo se describe uno de los tres puentes que Hidrocivil, S. A., ha construido.—previo concurso— en la región catalana; concretamente, el que salva el río Ripoll. Los otros dos no han sido objeto de descripción general por ser muy similares, en lo que a ejecución y concepción se refiere, con la única variante que presentan las características topográficas locales. La empresa propuso ciertas variantes— que fueron aceptadas— en la prefabricación y métodos de construcción. El interés de estas obras se centra en el empleo de vigas pretensadas, prefabricadas en taller por trozos, y solidarizados en el mismo mediante las operaciones

  16. Violencia con el anciano

    Directory of Open Access Journals (Sweden)

    Rita Campillo Motilva

    2002-08-01

    Full Text Available La violencia doméstica es tan antigua como la humanidad misma y se reconocen la violencia infantil, contra la mujer y al anciano, fundamentalmente; siendo este último grupo una población en ascenso por las mayores expectativas de vida de los últimos años. Como resultado de ello, el número de casos de abuso en el anciano se incrementará y el impacto de este abuso sobre la salud debe ser considerado de forma adecuada. La gama de maltratos es variadísima e incluye el abuso físico, emocional, financiero, sexual, por negligencia, negación a brindarle ayuda y otras formas más. Los ancianos con deterioro cognitivo son los más vulnerables. El médico en la atención primaria de salud es un pilar importante en la prevención y educación de este problema.Domestic violence is as old as humanity itself. Child, women and elderly abuse are mainly recognized. The elderly group is increasing due to the higher life expectancy experimented during the last years. As a result, the number of battered elderly will grow and the impact of this abuse on health should be adequately considered. The range of abuse is very wide and it includes physical, emotional, financial and sexual abuse, negligence, rejection to give assistance and others. The elderly with cognitive deterioration are the most vulnerable. The physician at the primary health care level is an important milestone in the prevention and education of this problem.

  17. Crescimento e estruturas do sistema digestório de larvas de pacu alimentadas com dieta microencapsulada produzida experimentalmente Growth and structure of the digestive system of pacu larvae fed microencapsulated diet produced experimentally

    Directory of Open Access Journals (Sweden)

    Olívia Cristina Camilo Menossi

    2012-01-01

    Full Text Available Foram comparados os efeitos de diferentes dietas e da transição alimentar sobre o desempenho zootécnico e a morfologia do trato digestório de larvas de pacu alimentadas com duas dietas comerciais e uma dieta experimental microencapsulada produzida por gelificação interna. Larvas com quatro dias de vida receberam os seguintes protocolos alimentares: somente náuplios de artêmia em quantidades crescentes (controle positivo; larvas mantidas em jejum (controle negativo; três tipos de alimento formulado durante todo o experimento (dieta experimental microencapsulada, dieta comercial NRD1.2/2.0, Inve, USA, e dieta Poli-Peixe 450F, PoliNutri, Brasil; e três protocolos de transição alimentar com náuplios de artêmia durante os seis primeiros dias, seis dias de coalimentação, e somente as respectivas dietas formuladas após esse período. O experimento foi conduzido por 23 dias em delineamento inteiramente casualizado, com avaliações periódicas do crescimento e do sistema digestório. A taxa de sobrevivência foi determinada ao final do experimento. Os melhores desempenhos de crescimento e sobrevivência, assim como mais acelerada organogênese do sistema digestório, foram verificados entre os animais que receberam alimento vivo. As larvas que passaram pela transição alimentar apresentaram médias intermediárias de crescimento e sobrevivência e não diferiram entre si. Entre os grupos que receberam apenas dieta inerte, somente naquele alimentado com a dieta nacional houve sobrevivência até o final do experimento. Nenhuma das dietas formuladas é adequada para uso como alimento exclusivo para larvas de pacu. Na fase de transição alimentar, a dieta experimental microencapsulada proporciona resultados de sobrevivência e crescimento semelhantes aos obtidos com dietas comerciais.The effects of different diets and dietary transition on the performance and morphology of the digestive tract of pacu larvae fed two commercial formulated

  18. Rastreabilidade da farinha de carne e ossos bovinos em ovos de poedeiras alimentadas com ingredientes alternativos Traceability of bovine meat and bone meal in eggs from laying hens fed with alternative ingredients

    Directory of Open Access Journals (Sweden)

    Juliana Célia Denadai

    2009-01-01

    Full Text Available O objetivo deste trabalho foi detectar traços de farinha de carne e ossos bovinos, em ovos de poedeiras alimentadas com dietas comerciais com inclusão de ingredientes vegetais alternativos e leveduras. A detecção foi feita pela técnica dos isótopos estáveis do carbono e do nitrogênio. Foram utilizadas 384 poedeiras, distribuídas aleatoriamente em oito tratamentos. Os tratamentos consistiram de uma dieta-controle - à base de milho e farelo de soja - e sete dietas com inclusão de farinha de carne e ossos bovinos, acrescidas ou não de outros ingredientes (farelo de trigo, quirera de arroz, farelo de algodão, glúten de milho, levedura de cana e levedura de cerveja. No 35º dia, foram tomados aleatoriamente 24 ovos por tratamento: 12 para análise de ovo e 12 para análise de gema e albúmen, em separado. Após análise isotópica de carbono e nitrogênio, os resultados foram submetidos à análise multivariada de variância. As médias dos pares isotópicos dos ovos, gema e albúmen, em todos os tratamentos, diferiram daquelas do tratamento-controle. A técnica dos isótopos estáveis permite detectar, nos ovos, gema e albúmen, a farinha de carne e ossos bovinos utilizada na dieta de poedeiras, mesmo com a inclusão de outros ingredientes vegetais e leveduras.The objective of this work was to detect traces of the bovine meat and bones meal in eggs of laying hens fed on commercial diets including alternative plant ingredients and yeast. The bovine meal detection was performed through carbon and nitrogen stable isotope technique. Three hundred eighty-four laying hens were randomly distributed in eight treatments. Treatments consisted of one control diet - a corn-and-soybean based meal - and seven diets with bovine meat and bone meal, including or not other ingredients (wheat bran, rice, cottonseed meal, corn gluten meal, sugarcane yeast and brewer yeast. At the 35th day, 24 eggs per treatment were randomly collected, 12 for egg analyses

  19. Pigmentação de gemas de ovos de codornas japonesas alimentadas com rações contendo colorífico Egg yolk colour of japanese quail fed on diets with spice

    Directory of Open Access Journals (Sweden)

    Newton Tavares Escocard de Oliveira

    2007-10-01

    Full Text Available Objetivou-se neste trabalho avaliar, semanalmente, o grau de pigmentação de gemas de ovos de codornas japonesas alimentadas com rações contendo diferentes níveis de colorífico (163,8 mg bixina/100 g, no decorrer de quatro semanas. Utilizaram-se 240 codornas japonesas (Coturnix japonica fêmeas, em delineamento experimental em blocos inteiramente casualizados, com oito tratamentos, cinco repetições e seis codornas por unidade experimental. Os tratamentos, constituídos por oito rações experimentais resultantes da combinação de quatro níveis de colorífico na ração (0; 1,5; 3,0 e 4,5% e duas fontes energéticas (milho e quirera de arroz, foram distribuídos nas parcelas, enquanto que os quatro dias experimentais (7º, 14º, 21º e 28º constituíram as subparcelas. A equação de regressão estimada com o uso do modelo logarítmico explicou 96% da variação dos dados de escore colorimétrico das gemas. No 7º e 14º dia do experimento, os níveis de colorífico estimados que promoveram escores colorimétricos de gemas com padrão caipira (8,5 a 9,0 pontos foram de 1,5%, em rações à base de milho, e 3,0%, em rações à base de quirera de arroz. No 21º e 28º dia experimental, os valores estimados foram de 0,75% (rações com milho e 2,25% (rações com quirera. Em rações com 46,0% de milho ou quirera de arroz, o uso de níveis superiores a 3,0% de colorífico promoveu aumento das perdas de pigmento, pelas excretas, e conseqüente redução da capacidade de deposição de pigmentos nas gemas.One aimed in this work to evaluate , weekly, the egg yolk colour grade of japanese quails fed on diets with different levels of spice (163.8 mg bixin/100 g, in course of four weeks. Two hundred and forty japanese female quails (Coturnix japonica were used in a completely randomized block outline, with eight treatments, five replicates and six quails per experimental unit. The treatments, consisted of eight experimental diets resultant from

  20. Combustion Sensors: Gas Turbine Applications

    Science.gov (United States)

    Human, Mel

    2002-01-01

    This report documents efforts to survey the current research directions in sensor technology for gas turbine systems. The work is driven by the current and future requirements on system performance and optimization. Accurate real time measurements of velocities, pressure, temperatures, and species concentrations will be required for objectives such as combustion instability attenuation, pollutant reduction, engine health management, exhaust profile control via active control, etc. Changing combustor conditions - engine aging, flow path slagging, or rapid maneuvering - will require adaptive responses; the effectiveness of such will be only as good as the dynamic information available for processing. All of these issues point toward the importance of continued sensor development. For adequate control of the combustion process, sensor data must include information about the above mentioned quantities along with equivalence ratios and radical concentrations, and also include both temporal and spatial velocity resolution. Ultimately these devices must transfer from the laboratory to field installations, and thus must become low weight and cost, reliable and maintainable. A primary conclusion from this study is that the optics-based sensor science will be the primary diagnostic in future gas turbine technologies.

  1. 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.)

  2. Low NOx combustion technologies for high-temperature natural gas combustion

    International Nuclear Information System (INIS)

    Flamme, Michael

    1999-01-01

    Because of the high process temperature which is required for some processes like glass melting and the high temperature to which the combustion air is preheated, NOx emission are extremely high. Even at these high temperatures, NOx emissions could be reduced drastically by using advanced combustion techniques such as staged combustion or flame-less oxidation, as experimental work has shown. In the case of oxy-fuel combustion, the NOx emission are also very high if conventional burners are used. The new combustion techniques achieve similar NOx reductions. (author)

  3. Advisable alternative fuels for Mexico; Combustibles alternativos convenientes para Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar Gonzalez, Jorge Luis [ICA Fluor (Mexico)

    2007-07-15

    The alternative fuels are born with the goal of not damaging the environment; biodiesel, electricity, ethanol, hydrogen, methanol, natural gas, LP gas, are the main alternative fuels. However, the biodiesel and bioetanol are the only completely renewable ones, this makes them ideal to be developed in Mexico, since the agricultural sector could be fortified, the technological independence be favored, improve the conservation of the oil resources and by all means not to affect the environment. On the other hand, also efficient cultivation techniques should be developed to guarantee the economy of the process. [Spanish] Los combustibles alternativos nacen con la meta de no danar el medio ambiente; el biodiesel, electricidad, etanol, hidrogeno, metanol, gas natural, gas LP, son los principales combustibles alternativos. No obstante, el biodiesel y el bioetanol son los unicos completamente renovables, esto los hace ideales para desarrollarse en Mexico, ya que se podria fortalecer el sector agricola, favorecer la independencia tecnologica, mejorar la administracion de los recursos petroleros y por supuesto no afectar al medio ambiente. Por otro lado tambien se tendrian que desarrollar tecnicas de cultivo eficientes para garantizar la economia del proceso.

  4. Study of mechanically activated coal combustion

    Directory of Open Access Journals (Sweden)

    Burdukov Anatolij P.

    2009-01-01

    Full Text Available Combustion and air gasification of mechanically activated micro-ground coals in the flux have been studied. Influence of mechanically activated methods at coals grinding on their chemical activeness at combustion and gasification has been determined. Intense mechanical activation of coals increases their chemical activeness that enables development of new highly boosted processing methods for coals with various levels of metamorphism.

  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. Flue Gas Emissions from Fluidized Bed Combustion

    NARCIS (Netherlands)

    Bramer, E.A.; Valk, M.

    1995-01-01

    During the past decades fluidized bed coal combustion was developed as a technology for burning coal in an effective way meeting the standards for pollution control. During the earlier years of research on fluidized bed combustion, the potential for limiting the S02 emission by adding limestone to

  7. Combustion and extinction of magnesium fires

    International Nuclear Information System (INIS)

    Malet, J.C.; Duverger de Cuy, G.

    1988-01-01

    The studies made in France on magnesium combustion and extinguishing means are associated at the nuclear fuel of the graphite-gas reactor. Safety studies are made for ameliorate our knowledge on: - magnesium combustion - magnesium fire propagation - magnesium fire extinguishing [fr

  8. Coal combustion ashes: A radioactive Waste?

    International Nuclear Information System (INIS)

    Michetti, F.P.; Tocci, M.

    1992-01-01

    The radioactive substances naturally hold in fossil fuels, such as Uranium and Thorium, after the combustion, are subjected to an increase of concentration in the residual combustion products as flying ashes or as firebox ashes. A significant percentage of the waste should be classified as radioactive waste, while the political strategies seems to be setted to declassify it as non-radioactive waste. (Author)

  9. 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)

  10. 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...

  11. 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.

  12. Ultra-low pollutant emission combustion method and apparatus

    International Nuclear Information System (INIS)

    Khinkis, M.J.

    1992-01-01

    This patent describes a method for ultra-low pollutant emission combustion of fossil fuel. It comprises: introducing into a primary combustion chamber a first fuel portion of about 1 percent to about 20 percent of a total fuel to be combusted; introducing primary combustion air into the primary combustion chamber; introducing a first portion of water into the primary combustion chamber, having a first water heat capacity equivalent to a primary combustion air heat capacity of one of a primary combustion air amount of about 10 percent to about 60 percent of the first stoichiometirc requirement for complete combustion of the first fuel portion and an excess primary combustion air amount of about 20 percent to about 150 percent of the first stoichiometric requirement for complete combustion of the first fuel portion; burning the first fuel portion with the primary combustion air in the primary combustion chamber at a temperature abut 2000 degrees F to about 2700 degrees F producing initial combustion products; passing the initial combustion products into a secondary combustion chamber; introducing into the secondary combustion chamber a second fuel portion of about 80 percent to about 99 percent of the total fuel to be combusted; introducing secondary combustion air into the secondary combustion chamber in an amount of about 105 percent to about 130 percent of a second stoichiometric requirement for complete combustion of the second fuel portion; introducing a second portion of water into the secondary combustion chamber; burning the second fuel portion and any remaining fuel in the initial combustion products; passing the final combustion products into a dilution chamber; introducing dilution air into the dilution chamber; discharging the ultra-low pollutant emission vitiated air form the dilution chamber

  13. Estudio calorimétrico de los cambios en la cristalinidad de membranas

    OpenAIRE

    Salla Tarragó, José María; Cadenato Matia, Ana María; Morancho Llena, José María; Fernández Francos, Xavier; Ramis Juan, Xavier

    2011-01-01

    En este trabajo se analizan los cambios en el grado de cristalización y en los hábitos cristalinos que el ácido sulfosuccínico (SSA) produce en membranas de polivinil alcohol (PVA). Las membranas resultantes del entrecruzamiento del PVA con SSA, un agente que incorpora además grupos sulfónicos que hacen al conjunto un buen conductor protónico, pueden utilizarse como electrolito en pilas de combustible alimentadas directamente con metanol (DMFC). Por medio de ensayos dinámicos d...

  14. 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

  15. 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.

  16. Experimental study on fuel oil combustion in circulating fluidized bed; Estudio experimental sobre la combustion de combustoleo en lecho fluidizado circulante

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Rangel, Ricardo [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1996-12-31

    The Instituto de Investigaciones Electricas (IIE) developed a circulating fluidized bed combustor of 0.5 thermal MW unique in its type in Latin America. The Bachelor`s thesis entitled ``Experimental Study on Fuel Oil Combustion in Circulating Fluidized Bed`` was performed operating this combustor with the purpose of determining the feasibility of burning heavy fuel oil in a stable and sustained form, as well as the effect of the addition of calcium carbonate to the combustor. The results of the experimental trials showed heavy fuel oil can be burned in a circulating fluidized bed, with low sulfur dioxide emissions. During the conduction of the experiments a sulfur retention of 43% was achieved with a Ca/S relationship of 4.5. [Espanol] El Instituto de Investigaciones Electricas (IIE) desarrollo un combustor de lecho fluidizado circulante de 0.5 MW termicos de potencia, unico en su tipo en Latinoamerica. La tesis de licenciatura titulada Estudio Experimental sobre la Combustion de Combustoleo en Lecho Fluidizado Circulante se realizo operando dicho combustor, con el proposito de determinar la factibilidad de quemar combustoleo pesado en forma estable y autosostenida, asi como la influencia que tiene la adicion de carbonato de calcio al lecho. Los resultados de los ensayos experimentales mostraron que se puede quemar combustoleo pesado en un lecho fluidizado circulante, con bajas emisiones de bioxido de azufre. Durante la experimentacion se logro una retencion de azufre del 43%, con una relacion Ca/S de 4.5.

  17. Experimental study on fuel oil combustion in circulating fluidized bed; Estudio experimental sobre la combustion de combustoleo en lecho fluidizado circulante

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Rangel, Ricardo [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    The Instituto de Investigaciones Electricas (IIE) developed a circulating fluidized bed combustor of 0.5 thermal MW unique in its type in Latin America. The Bachelor`s thesis entitled ``Experimental Study on Fuel Oil Combustion in Circulating Fluidized Bed`` was performed operating this combustor with the purpose of determining the feasibility of burning heavy fuel oil in a stable and sustained form, as well as the effect of the addition of calcium carbonate to the combustor. The results of the experimental trials showed heavy fuel oil can be burned in a circulating fluidized bed, with low sulfur dioxide emissions. During the conduction of the experiments a sulfur retention of 43% was achieved with a Ca/S relationship of 4.5. [Espanol] El Instituto de Investigaciones Electricas (IIE) desarrollo un combustor de lecho fluidizado circulante de 0.5 MW termicos de potencia, unico en su tipo en Latinoamerica. La tesis de licenciatura titulada Estudio Experimental sobre la Combustion de Combustoleo en Lecho Fluidizado Circulante se realizo operando dicho combustor, con el proposito de determinar la factibilidad de quemar combustoleo pesado en forma estable y autosostenida, asi como la influencia que tiene la adicion de carbonato de calcio al lecho. Los resultados de los ensayos experimentales mostraron que se puede quemar combustoleo pesado en un lecho fluidizado circulante, con bajas emisiones de bioxido de azufre. Durante la experimentacion se logro una retencion de azufre del 43%, con una relacion Ca/S de 4.5.

  18. 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.

  19. Solid waste combustion for alpha waste incineration

    International Nuclear Information System (INIS)

    Orloff, D.I.

    1981-02-01

    Radioactive waste incinerator development at the Savannah River Laboratory has been augmented by fundamental combustion studies at the University of South Carolina. The objective was to measure and model pyrolysis and combustion rates of typical Savannah River Plant waste materials as a function of incinerator operating conditions. The analytical models developed in this work have been incorporated into a waste burning transient code. The code predicts maximum air requirement and heat energy release as a function of waste type, package size, combustion chamber size, and temperature. Historically, relationships have been determined by direct experiments that did not allow an engineering basis for predicting combustion rates in untested incinerators. The computed combustion rates and burning times agree with measured values in the Savannah River Laboratory pilot (1 lb/hr) and full-scale (12 lb/hr) alpha incinerators for a wide variety of typical waste materials

  20. Final report: Prototyping a combustion corridor; FINAL

    International Nuclear Information System (INIS)

    Rutland, Christopher J.; Leach, Joshua

    2001-01-01

    The Combustion Corridor is a concept in which researchers in combustion and thermal sciences have unimpeded access to large volumes of remote computational results. This will enable remote, collaborative analysis and visualization of state-of-the-art combustion science results. The Engine Research Center (ERC) at the University of Wisconsin - Madison partnered with Lawrence Berkeley National Laboratory, Argonne National Laboratory, Sandia National Laboratory, and several other universities to build and test the first stages of a combustion corridor. The ERC served two important functions in this partnership. First, we work extensively with combustion simulations so we were able to provide real world research data sets for testing the Corridor concepts. Second, the ERC was part of an extension of the high bandwidth based DOE National Laboratory connections to universities

  1. Estabilidad oxidativa de huevos enriquecidos con ácidos grasos poliinsaturados omega 3, frente a antioxidantes naturales Estabilidade oxidativa de ovos enriquecidos com ácidos graxos poliinsaturados ômega 3, frente a antioxidantes naturais

    Directory of Open Access Journals (Sweden)

    María Elena Bernal Gómez

    2003-12-01

    Full Text Available Fueron alimentadas 192 gallinas ponedoras de 22 semanas de edad, de linaje comercial Babcock, durante 30 días con dietas de 0 (cero y 12,7% de semilla de linaza molida que corresponde a 0 y 5% de aceite de linaza, respectivamente. Fueron definidos 8 tratamientos: 4 grupos con 12,7% de semilla de linaza (control/sin antioxidante; BHA+BHT, 100+100 ppm; orégano, 200 ppm; romero, 200 ppm y 4 grupos sin semilla de linaza, pero utilizando los mismos antioxidantes. Este estudio fue realizado con el objetivo de verificar la eficacia del uso de antioxidantes naturales provenientes del orégano y del romero en la protección contra el deterioro oxidativo de la fracción lipídica de las yemas de los huevos enriquecidos con ácidos grasos poliinsaturados omega 3 (PUFA É-3. El grado de oxidación lipídica fue determinado a través de la prueba TBARS (substancias reactivas con ácido tiobarbitúrico. Según los resultados obtenidos, fue verificada diferencia significativa en la reducción del grado de oxidación lipídica de las yemas de huevo en todos los tratamientos con antioxidantes, cuando se compara con el control. Por lo tanto, los extratos de los condimentos, romero y orégano, pueden ser utilizados satisfactoriamente para obtener huevos enriquecidos con PUFA É-3, mejorando la estabilidad lipídica.Foram alimentadas 192 galinhas poedeiras de 22 semanas de idade da linhagem comercial Babcock, durante 30 dias com dietas constituídas de 0 (zero e 12,7% de semente de linhaça moída correspondente a 0 e 5% de óleo de linhaça, respectivamente. Foram definidos 8 tratamentos: 4 grupos com 5% de óleo de linhaça (controle/sem antioxidante; BHA+BHT, 100+100 ppm; orégano, 200 ppm; alecrim, 200 ppm e 4 grupos sem óleo de linhaça, mas utilizando os mesmos antioxidantes. Este estudo foi realizado com o objetivo de verificar a eficácia do uso de antioxidantes naturais provenientes do orégano e do alecrim, na proteção contra a deteriora

  2. Modeling and simulating combustion and generation of NOx

    International Nuclear Information System (INIS)

    Lazaroiu, Gheorghe

    2007-01-01

    This paper deals with the modeling and simulation of combustion processes and generation of NO x in a combustion chamber and boiler, with supplementary combustion in a gas turbine installation. The fuel burned in the combustion chamber was rich gas with a chemical composition more complex than natural gas. Pitcoal was used in the regenerative boiler. From the resulting combustion products, 17 compounds were retained, including nitrogen and sulphur compounds. Using the developed model, the simulation resulted in excess air for a temperature imposed at the combustion chamber exhaust. These simulations made it possible to determine the concentrations of combustion compounds with a variation in excess combustion. (author)

  3. Retardo de crecimiento intrauterino: relación con la gonadectomía y la hormona de crecimiento durante el crecimiento postnatal

    Directory of Open Access Journals (Sweden)

    Quintero, Fabián

    2003-01-01

    Full Text Available Los resultados de la terapia con hormona de crecimiento (HC en niños con retardo del crecimiento intrauterino (RCI no son conclusivos y plantean la necesidad de analizar la posible interacción de la HC con otras hormonas. El objetivo de este trabajo es analizar el efecto de la castración y la administración de HC en animales con RCI experimental. Se conformaron los siguientes grupos experimentales: Control, Sham, RCI, RCI gonadectomizadas y RCI gonadectomizadas y tratadas con HC. El retardo de crecimiento intrauterino (RCI fue inducido por obstrucción parcial de la circulación uterina el día 14 de gestación. Al nacimiento las crías de los grupos Sham y RCI fueron transferidas a madres control. Al destete, fueron alimentadas con dieta stock ad libitum. Se calculó el consumo alimentario de cada animal y se registró semanalmente el peso corporal. Los datos fueron procesados por análisis de varianza y pruebas post hoc LSD. Los resultados obtenidos indicaron que la rehabilitación nutricional lactacional y postlactacional no es suficiente para revertir los efectos del estrés intrauterino. La ausencia de testosterona parece inhibir la ganancia de peso corporal, de tal modo que aún cuando la administración de HC promueve la ganancia de peso corporal, éste no alcanza los valores control. Contrariamente la ausencia de estrógenos promueve el catch up del peso corporal. Esta compensación es más temprana en presencia de HC. Se concluye que existiría una interacción entre las hormonas sexuales y la HC: mientras la HC induce un efecto catabólico en ausencia de testosterona (mayor consumo-menor peso, en ausencia de estrógenos induce un efecto anabólico (menor consumo-mayor peso.

  4. Dry low NOx combustion system with pre-mixed direct-injection secondary fuel nozzle

    Science.gov (United States)

    Zuo, Baifang; Johnson, Thomas; Ziminsky, Willy; Khan, Abdul

    2013-12-17

    A combustion system includes a first combustion chamber and a second combustion chamber. The second combustion chamber is positioned downstream of the first combustion chamber. The combustion system also includes a pre-mixed, direct-injection secondary fuel nozzle. The pre-mixed, direct-injection secondary fuel nozzle extends through the first combustion chamber into the second combustion chamber.

  5. 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...

  6. Radiation treatment of combustion gases

    International Nuclear Information System (INIS)

    Machi, S.; Tokunaga, O.; Nishimura, K.; Hasimoto, S.; Kawakami, W.; Washino, M.; Kawamura, K.; Aoki, S.; Adachi, K.

    1977-01-01

    A pilot plant for the radiation treatment of combustion gas in a flow-system was planned and completed in 1974 at the Abara Mfg. Co. Ltd., Central Laboratory in Fujisawa. The plant has been successfully operated for more than one year. The capacity of the pilot plant is 1000 Nm 3 per hour of the gas with the use of an electron accelerator of 60 mA and 0.75 MeV. The objective of this paper is to review a series of the researches including recent unpublished results, and to discuss the characteristics of the process. The outline and typical results of the pilot plant are first reported here. (author)

  7. Ignition circuit for combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Becker, H W

    1977-05-26

    The invention refers to the ignition circuit for combustion engines, which are battery fed. The circuit contains a transistor and an oscillator to produce an output voltage on the secondary winding of an output transformer to supply an ignition current. The plant is controlled by an interrupter. The purpose of the invention is to form such a circuit that improved sparks for ignition are produced, on the one hand, and that on the other hand, the plant can continue to function after loss of the oscillator. The problem is solved by the battery and the secondary winding of the output transformers of the oscillator are connected via a rectifier circuit to produce a resultant total voltage with the ignition coil from the battery voltage and the rectified pulsating oscillator output.

  8. Trace emissions from gaseous combustion

    Energy Technology Data Exchange (ETDEWEB)

    Seebold, J.G. [Chevron Research and Technology Co., Richmond, CA (United States)

    2000-07-01

    The U.S. Clean Air Act (CAA) was amended in 1990 to include the development of maximum achievable control technology (MACT) emission standards for hazardous air pollutants (HAPs) for certain stationary sources by November 2000. MACT emissions standards would affect process heaters and industrial boilers since combustion processes are a potential source for many air toxins. The author noted that one of the problems with MACT is the lack of a clear solid scientific footing which is needed to develop environmentally responsible regulations. In order to amend some of these deficiencies, a 4-year, $7 million research project on the origin and fate of trace emissions in the external combustion of gaseous hydrocarbons was undertaken in a collaborative effort between government, universities and industry. This collaborative project entitled the Petroleum Environmental Research Forum (PERF) Project 92-19 produced basic information and phenomenological understanding in two important areas, one basic and one applied. The specific objectives of the project were to measure emissions while operating different full-scale burners under various operating conditions and then to analyze the emission data to identify which operating conditions lead to low air toxic emissions. Another objective was to develop new chemical kinetic mechanisms and predictive models for the formation of air toxic species which would explain the origin and fate of these species in process heaters and industrial boilers. It was determined that a flame is a very effective reactor and that trace emissions from a typical gas-fired industry burner are very small. An unexpected finding was that trace emissions are not affected by hydrocarbon gaseous fuel composition, nor by the use of ultra low nitrous oxide burners. 2 refs., 8 figs.

  9. Acne polimorfo: tratamiento con Implacen

    Directory of Open Access Journals (Sweden)

    Rubén Pérez Armas

    1995-06-01

    Full Text Available Se realiza el estudio de 40 pacientes con acné polimorfo, los que fueron atendidos en la Consulta de Dermatología del Hospital Provincial Clinicoquirúrgico Docente "Celia Sánchez Manduley", en el período comprendido de enero de 1988 a diciembre de 1989. Se revisa la literatura médica sobre los diversos métodos y medicamentos utilizados en la terapéutica de esta dermatosis. Se describe el esquema de tratamiento empleado con implacén en 30 pacientes; los 10 restantes se trataron con placebo; se compara dicho esquema con los tradicionales y se observan mejores resultados con nuestro estudio. Se destaca la ausencia de recaídas, así como el resultado del tratamiento de acuerdo con el sexo.A study was performed in 40 patients presenting with polymorphic acne who were attended in the Dermatology Department of "Celia Sánchez Manduley" Clinicosurgical and Teaching Hospital from January, 1988 to December, 1989. A review of the literature was made seeking for the different methods and drugs used for the treatment of this dermatosis. The treatment schedule with the use of implacen in 30 patients is described. Such therapeutic schedule was compared with traditional ones and better results were observed with the use of implacen. The fact that there were no relapses is highlighted, as well as the result of treatment according to sex.

  10. Effect of Variant End of Injection Period on Combustion Process of Biodiesel Combustion

    Directory of Open Access Journals (Sweden)

    Khalid Amir

    2016-01-01

    Full Text Available Biodiesel is an alternative fuel as a replacement to the standard diesel fuel in combustion diesel engine. The biodiesel fuel has a significantly influences throughout the combustion process and exhaust emission. The purpose of this research is to investigate the combustion process behavior during the End of Injection (EOI period and operates under variant conditions using Rapid Compression Machine (RCM. Experimental of RCM is used to simulate a combustion process and combustion characteristics of diesel engine combustion. Three types of biodiesel blend which are B5, B10 and B15 were tested at several injection pressures of 80 MPa, 90 MPa and 130 MPa under different ambient temperatures, 750 K to 1100 K. The results of this study showed that the ignition delay slightly reduced with increasing the content of biodiesel blends from B5, B10 and B15 and became more shorten as the injection pressure been enhanced. As the injection pressure increased, the behavior of combustion pressure at end of injection is reduced, radically increased the NOX emission. It is noted that the process of combustion at the end of injection increased as the ambient temperature is rising. In fact, higher initial ambient temperature improved the fuel atomization and mixing process. Under the biodiesel combustion with higher ambient temperature condition, the exhaust emission of CO, O2, and HC became less but increased in NOX emission. Besides, increased in blends of biodiesel ratio are found to enhance the combustion process, resulted a decreased in HC emissions.

  11. 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.

  12. Bifurcation, pattern formation and chaos in combustion

    International Nuclear Information System (INIS)

    Bayliss, A.; Matkowsky, B.J.

    1991-01-01

    In this paper problems in gaseous combustion and in gasless condensed phase combustion are studied both analytically and numerically. In gaseous combustion we consider the problem of a flame stabilized on a line source of fuel. The authors find both stationary and pulsating axisymmetric solutions as well as stationary and pulsating cellular solutions. The pulsating cellular solutions take the form of either traveling waves or standing waves. Transitions between these patterns occur as parameters related to the curvature of the flame front and the Lewis number are varied. In gasless condensed phase combustion both planar and nonplanar problems are studied. For planar condensed phase combustion we consider two models: accounts for melting and does not. Both models are shown to exhibit a transition from uniformly to pulsating propagating combustion when a parameter related to the activation energy is increased. Upon further increasing this parameter both models undergo a transition to chaos: by intermittency and by a period doubling sequence. In nonplanar condensed phase combustion the nonlinear development of a branch of standing wave solutions is studied and is shown to lead to relaxation oscillations and subsequently to a transition to quasi-periodicity

  13. Thermogravimetric analysis of biowastes during combustion

    International Nuclear Information System (INIS)

    Otero, M.; Sanchez, M.E.; Gomez, X.; Moran, A.

    2010-01-01

    The combustion of sewage sludge (SS), animal manure (AM) and the organic fraction of municipal solid waste (OFMSW) was assessed and compared with that of a semianthracite coal (SC) and of a PET waste by thermogravimetric (TG) analysis. Differences were found in the TG curves obtained for the combustion of these materials accordingly to their respective proximate analysis. Non-isothermal thermogravimetric data were used to assess the kinetics of the combustion of these biowastes. The present paper reports on the application of the Vyazovkin model-free isoconversional method for the evaluation of the activation energy necessary for the combustion of these biowastes. The activation energy related to SS combustion (129.1 kJ/mol) was similar to that corresponding to AM (132.5 kJ/mol) while the OFMSW showed a higher value (159.3 kJ/mol). These values are quite higher than the one determined in the same way for the combustion of SC (49.2 kJ/mol) but lower than that for the combustion of a PET waste (165.6 kJ/mol).

  14. 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.)

  15. Catalytic combustion in small wood burning appliances

    Energy Technology Data Exchange (ETDEWEB)

    Oravainen, H [VTT Energy, Jyvaeskylae (Finland)

    1997-12-31

    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.)

  16. El biodiesel de aceite de higuerilla como combustible alternativo para motores diesel

    Directory of Open Access Journals (Sweden)

    ALIRIO BENAVIDES

    2007-01-01

    Full Text Available En este artículo se presenta un estudio experimental sobre la producción y utilización del biodiesel de aceite de higuerilla. El máximo rendimiento de metilésteres en la reacción de transesterificación del aceite de higuerilla usado se obtiene bajo las siguientes condiciones: temperatura ambiente, una relación molar metanol/aceite de 9 y una concentración de catalizador de 0.8%. El biodiesel de aceite de higuerilla puede ser mezclado con el combustible diesel convencional derivado del petróleo en proporciones hasta del 15%, sin que la mezcla resultante se salga de las especificaciones de calidad estipuladas en los estándares nacionales e internacionales para combustibles diesel. La mayor dificultad para el uso del biodiesel de aceite de higuerilla en motores es su alta viscosidad. Sin embargo este biocombustible presenta excelentes propiedades de flujo a baja temperatura (valores bajos para los puntos de nube y fluidez. Las pruebas en motor con mezclas biodiesel de higuerilla/diesel convencional, en el rango de proporciones de biodiesel ensayadas, muestran que ha medida que se incrementa la proporción de biodiesel en la mezcla aumenta el consumo específico de combustible, disminuye el dosado relativo, la opacidad de humos se disminuye levemente, mientras que el rendimiento efectivo y las emisiones de CO y CO2 prácticamente permanecen constantes

  17. Estudio comparativo de clinkers producidos con diferentes reemplazos de combustibles residuales

    Directory of Open Access Journals (Sweden)

    Trezza Mónica Adriana

    2003-01-01

    Full Text Available In the last decades the cement industry has used, as a partial substitute for traditional fuel, different industrial wastes in order to profit their residuals energy. In the present work the physicochemical characteristics of clinker, obtained using trade marked alternative fuel for clinker kiln, were evaluated. X-ray diffraction (XRD, Blaine specific surface, pyrometric cone equivalent (PCE, differential thermal analysis-thermal gravimetry simultaneous (DTA-TG, differential calorimetry, porosimetry and mechanical strength were used as the main evaluation techniques of the characteristic of clinker and their behaviors in the early hydration. The additions of the wastes, within the percentages and under the conditions of this test, does no significantly alter the clinker properties but generates a greater crystallinity of the principal clinker phases.

  18. 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.

  19. 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

  20. Characteristic of combustion of Colombian gases

    International Nuclear Information System (INIS)

    Gil B, Edison; Maya, Ruben; Andres, Amel A.

    1996-01-01

    The variety of gas locations in the country, makes that the gas that will be distributed by the net of present gas pipeline a very different composition, what bears to that these they behave in a different way during its use. In this work the main characteristics of the combustion are calculated for the Colombian gases, basically the properties of the combustion and the characteristics of the smoke, as basic information for the design and operation of the gas teams and their certification. These properties were calculated with the special help software for combustion developed by the authors

  1. Combustion of fuels with low sintering temperature

    Energy Technology Data Exchange (ETDEWEB)

    Dalin, D

    1950-08-16

    A furnace for the combustion of low sintering temperature fuel consists of a vertical fuel shaft arranged to be charged from above and supplied with combustion air from below and containing a system of tube coils extending through the fuel bed and serving the circulation of a heat-absorbing fluid, such as water or steam. The tube-coil system has portions of different heat-absorbing capacity which are so related to the intensity of combustion in the zones of the fuel shaft in which they are located as to keep all parts of the fuel charge below sintering temperature.

  2. 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.

  3. 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.

  4. 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.

  5. Plasma assisted combustion of parafin mixture

    International Nuclear Information System (INIS)

    Nedybaliuk, O.A.; Chernyak, V.Ya.; Martysh, E.V.; Lisitchenko, T.E.; Vergun, O.Yu.; Orlovska, S.G.

    2013-01-01

    In this work the results of solid paraffin combustion with the aid of the plasma of transverse and rotational gliding arc studies are represented. The question of the additional activation of paraffin based solid fuels is examined. The mixture of n-paraffin and stearin in the solid state as the model of the solid paraffin based fuel is used. The plasma assisted combustion of this model is experimentally investigated. The voltage-current characteristics of discharge at the different regimes are measured. The population temperatures of excited rotational levels are determined. The flame temperature during the combustion of solid paraffin containing mixture is calculated

  6. Chaotic combustion in spark ignition engines

    International Nuclear Information System (INIS)

    Wendeker, Miroslaw; Czarnigowski, Jacek; Litak, Grzegorz; Szabelski, Kazimierz

    2003-01-01

    We analyse the combustion process in a spark ignition engine using the experimental data of an internal pressure during the combustion process and show that the system can be driven to chaotic behaviour. Our conclusion is based on the observation of unperiodicity in the time series, suitable stroboscopic maps and a complex structure of a reconstructed strange attractor. This analysis can explain that in some circumstances the level of noise in spark ignition engines increases considerably due to nonlinear dynamics of a combustion process

  7. con mala calidad de vida

    Directory of Open Access Journals (Sweden)

    Agustín Martín-Rodríguez

    2007-01-01

    Full Text Available En este estudio ex post facto se ha analizado si los familiares de pacientes con mala calidad de vida presentan diferencias en las variables clínicas de personalidad y relaciones familiares en función de que el paciente haya estado o no ingresado en una Unidad de Cuidados Intensivos. Seleccionamos dos grupos: 29 familiares de pacientes traumatizados graves transcurridos cuatro años de su ingreso en una UCI de Traumatología y con mala calidad de vida (debido a secuelas físicas y/o psicológicas tras el ingreso, tales como traumatismos craneoencefálicos, politraumatismos y tetraplejias traumáticas y 32 familiares de pacientes con mala calidad de vida con cuatro años de evolución de su enfermedad física (hipertensión, diabetes, artritis reumatoide y síndrome de intestino irritable que no han estado ingresados en la UCI. Para alcanzar nuestro objetivo empleamos una Encuesta Psicosocial y los siguientes instrumentos: Cuestionario de Análisis Clínico, Escala de Clima Social en la Familia y Escala de Adaptación Psicosocial de la Enfermedad. Los resultados mostraron que los familiares de pacientes con mala calidad de vida que estuvieron ingresados en la UCI hace cuatro años, presentan diferencias significativas en las variables agitación y expresividad comparados con los familiares de pacientes con mala calidad de vida que no han estado ingresados en la UCI.

  8. Gradual combustion - method for nitrogen oxide suppression during brown coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Kotler, V.P.; Verzakov, V.N.; Lobov, T.V.

    1990-10-01

    Discusses combustion of brown coal in BKZ-500-140-1 boilers and factors that influence emission of nitrogen oxides. Temperature distribution in the furnace was evaluated. Effects of burner position, burner number and burner type as well as air excess ratio on chemical reactions during brown coal combustion, formation of nitrogen oxides and their emission were comparatively evaluated. Analyses showed that by optimum arrangement of burners and selecting the optimum air excess ratio a part of nitrogen oxides formed during the initial phase of combustion was reduced to molecular nitrogen in the second phase. On the basis of evaluations the following recommendations for furnace design are made: use of straight-flow burners characterized by a reduced mixing ratio with secondary air, parallel arrangement of burners which guarantees mixing of the combustion products from the burners with stable and unstable combustion (products of incomplete coal combustion), reducing the air excess ratio to below 1.0. 5 refs.

  9. 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.

  10. 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.

  11. Comparison of different chemical kinetic mechanisms of methane combustion in an internal combustion engine configuration

    OpenAIRE

    Ennetta Ridha; Hamdi Mohamed; Said Rachid

    2008-01-01

    Three chemical kinetic mechanisms of methane combustion were tested and compared using the internal combustion engine model of Chemkin 4.02 [1]: one-step global reaction mechanism, four-step mechanism, and the standard detailed scheme GRIMECH 3.0. This study shows good concordances, especially between the four-step and the detailed mechanisms in the prediction of temperature and main species profiles. But reduced schemes were incapables to predict pollutant emissions in an internal combustion...

  12. 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

  13. 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.

  14. Distillation of combustibles at temperatures below fusion

    Energy Technology Data Exchange (ETDEWEB)

    Dalin, D

    1946-09-26

    A process is described for combustion and distillation for dry fuels, such as bituminous shales, below the temperature of fusion of the ash, for the production of heat, in which the temperature in the charge of fuel forming a vertical column is maintained beneath the temperature of fusion of the ash by a withdrawal of the heat from the combustible charge by means of a fluid absorbing this heat. This fluid being constituted, for example, by water in a suitable form, so that it can be circulated through a convenient cooling system, extending through the different parts of the charge. The fluid circulating also through the desired parts of the charge and absorbing the heat, the quantity of fluid or the surface of absorption increasing with the intensity of the combustion in the part of the combustible charge traversed by the fluid.

  15. 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...

  16. 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...

  17. CloudFlame: Cyberinfrastructure for combustion research

    KAUST Repository

    Goteng, Gokop; Nettyam, Naveena; Sarathy, Mani

    2013-01-01

    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

  18. Flex-flame burner and combustion method

    Science.gov (United States)

    Soupos, Vasilios; Zelepouga, Serguei; Rue, David M.; Abbasi, Hamid A.

    2010-08-24

    A combustion method and apparatus which produce a hybrid flame for heating metals and metal alloys, which hybrid flame has the characteristic of having an oxidant-lean portion proximate the metal or metal alloy and having an oxidant-rich portion disposed above the oxidant lean portion. This hybrid flame is produced by introducing fuel and primary combustion oxidant into the furnace chamber containing the metal or metal alloy in a substoichiometric ratio to produce a fuel-rich flame and by introducing a secondary combustion oxidant into the furnace chamber above the fuel-rich flame in a manner whereby mixing of the secondary combustion oxidant with the fuel-rich flame is delayed for a portion of the length of the flame.

  19. System and method for engine combustion

    Science.gov (United States)

    Sczomak, David P.; Gallon, Robert J.; Solomon, Arun S.

    2018-03-13

    A combustion system for use with one or more cylinder bores of an internal combustion engine includes at least one cylinder head defining first and second intake ports in fluid communication with the one or more cylinder bores. A flap is adjustably connected to the at least one cylinder head. The flap includes a first flap portion cooperating with the first intake port extending from an arm and a second flap portion cooperating with the second intake port extending from the arm and disposed adjacent the first flap portion. A controller in electrical communication with an actuator monitors the condition of the engine and actuates the flap to position the first and second flap portions between first and second positions to create a first combustion condition and a second combustion condition.

  20. Engine combustion control via fuel reactivity stratification

    Science.gov (United States)

    Reitz, Rolf Deneys; Hanson, Reed M; Splitter, Derek A; Kokjohn, Sage L

    2013-12-31

    A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choose the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).

  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, 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....

  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, 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....

  3. 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.

  4. Produção de proteína microbiana e parâmetros ruminais em vacas leiteiras alimentadas com farelo de trigo Microbial protein production and ruminal parameters in dairy cows fed wheat middlings

    Directory of Open Access Journals (Sweden)

    Carla Aparecida Soares

    2005-02-01

    Full Text Available Doze vacas Holandesas foram distribuídas em três quadrados latinos 4 x 4, balanceados de acordo com o período de lactação, com o objetivo de estimar a produção de proteína microbiana, utilizando-se a excreção total de derivados de purinas (DP a partir de coletas spot de urina, as concentrações de nitrogênio (N-uréia no plasma, no leite e na urina, o pH e a concentração de amônia ruminal. As quatro rações experimentais foram formuladas para conter na base da matéria seca 70% de silagem de milho e 30% de concentrado. Foram utilizados níveis crescentes de farelo de trigo no concentrado (0, 33, 67 e 100% em substituição ao fubá de milho. As concentrações de uréia (38,8 mg/dL e N-uréia (18,1 mg/dL no leite não foram afetados pelos níveis de farelo de trigo, assim como as concentrações plasmáticas de uréia (51,1 mg/dL e N-uréia (23,8 mg/dL. As excreções urinárias de uréia, N-uréia, alantoína, DP, purinas absorvidas, N-microbiano e concentração de alantoína no leite não foram alteradas. Entretanto, a excreção de ácido úrico apresentou comportamento quadrático, com valor máximo de 40,03 mmol/dia no nível de 36% de farelo de trigo. O pH e a concentração de amônia ruminal antes e após a alimentação também não foram afetados pelos níveis de farelo de trigo. O fubá de milho pode ser substituído integralmente pelo farelo de trigo no concentrado de vacas leiteiras, com produção de leite média de 20 kg/dia, alimentadas com dietas à base de silagem de milho, sem que ocorra alteração na produção de proteína microbiana e no pH e concentração de amônia ruminal.Twelve Holstein cows were allotted to four 4 x 4 Latin square balanced in accordance with the lactation period, with the objective of evaluating the protein production, using the total purine derivatives (PD excretion, obtained from spot urine collection, the plasma and milk urea and nitrogen(N-urea, pH and ruminal ammonia

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. COMBUSTION OPTIMIZATION IN SPARK IGNITION ENGINES

    OpenAIRE

    Barhm Mohamad; Gabor Szebesi; Betti Bollo

    2017-01-01

    The blending technique used in internal combustion engines can reduce emission of toxic exhaust components and noises, enhance overall energy efficiency and reduce fuel costs. The aim of the study was to compare the effects of dual alcohols (methanol and ethanol) blended in gasoline fuel (GF) against performance, combustion and emission characteristics. Problems arise in the fuel delivery system when using the highly volatile methanol - gasoline blends. This problem is reduced by using specia...

  10. 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.

  11. 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.

  12. LES and RANS modeling of pulverized coal combustion in swirl burner for air and oxy-combustion technologies

    International Nuclear Information System (INIS)

    Warzecha, Piotr; Boguslawski, Andrzej

    2014-01-01

    Combustion of pulverized coal in oxy-combustion technology is one of the effective ways to reduce the emission of greenhouse gases into the atmosphere. The process of transition from conventional combustion in air to the oxy-combustion technology, however, requires a thorough investigations of the phenomena occurring during the combustion process, that can be greatly supported by numerical modeling. The paper presents the results of numerical simulations of pulverized coal combustion process in swirl burner using RANS (Reynolds-averaged Navier–Stokes equations) and LES (large Eddy simulation) methods for turbulent flow. Numerical simulations have been performed for the oxyfuel test facility located at the Institute of Heat and Mass Transfer at RWTH Aachen University. Detailed analysis of the flow field inside the combustion chamber for cold flow and for the flow with combustion using different numerical methods for turbulent flows have been done. Comparison of the air and oxy-coal combustion process for pulverized coal shows significant differences in temperature, especially close to the burner exit. Additionally the influence of the combustion model on the results has been shown for oxy-combustion test case. - Highlights: • Oxy-coal combustion has been modeled for test facility operating at low oxygen ratio. • Coal combustion process has been modeled with simplified combustion models. • Comparison of oxy and air combustion process of pulverized coal has been done. • RANS (Reynolds-averaged Navier–Stokes equations) and LES (large Eddy simulation) results for pulverized coal combustion process have been compared

  13. Tratamiento con implantes Leader-Nano en paciente con oligodoncia

    Directory of Open Access Journals (Sweden)

    Salvador Javier Santos Medina

    2015-03-01

    Full Text Available Los implantes dentales de titanio han revolucionado el mundo de la rehabilitación desde su surgimiento. De manera particular, el empleo de implantes de carga inmediata acorta el tiempo quirúrgico y protésico, con el consiguiente bienestar estético. Se presenta el caso de una paciente femenina de 32 años de edad, con antecedentes de oligodoncia de ambos incisivos laterales superiores y portadora de prótesis parcial acrílica. Fue atendida por el equipo multidisciplinario de implantes en la Clínica Estomatológica Docente “3 de Octubre” y se le realizó tratamiento de rehabilitación integral con implantes Leader-Nano y prótesis fija con corona acrílica sobre dichos implantes. La implantología fue satisfactoria en la paciente; la mejoría estética y funcional, así como la satisfacción de la paciente, fueron los principales logros obtenidos

  14. 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.)

  15. Science review of internal combustion engines

    International Nuclear Information System (INIS)

    Taylor, Alex M.K.P.

    2008-01-01

    Internal combustion engines used in transportation produce about 23% of the UK's carbon dioxide emission, up from 14% in 1980. The current science described in this paper suggests that there could be 6-15% improvements in internal combustion fuel efficiency in the coming decade, although filters to meet emission legislation reduce these gains. Using these engines as hybrids with electric motors produces a reduction in energy requirements in the order of 21-28%. Developments beyond the next decade are likely to be dominated by four topics: emission legislation and emission control, new fuels, improved combustion and a range of advanced concepts for energy saving. Emission control is important because current methods for limiting nitrogen oxides and particulate emissions imply extra energy consumption. Of the new fuels, non-conventional fossil-derived fuels are associated with larger greenhouse gas emissions than conventional petroleum-based fuels, while a vehicle propelled by fuel cells consuming non-renewable hydrogen does not necessarily offer an improvement in emissions over the best hybrid internal combustion engines. Improved combustion may be developed for both gasoline and diesel fuels and promises better efficiency as well as lower noxious emissions without the need for filtering. Finally, four advanced concepts are considered: new thermodynamic cycles, a Rankine bottoming cycle, electric turbo-compounding and the use of thermoelectric devices. The latter three all have the common theme of trying to extract energy from waste heat, which represents about 30% of the energy input to an internal combustion engine

  16. Control device for combustible gas concentration

    International Nuclear Information System (INIS)

    Osawa, Yasuo.

    1988-01-01

    Purpose: To control the concentration of combustible gases such as hydrogen evolved in a reactor container upon loss-of-coolant accidents. Constitution: Combustible gases evolved from the lower area of a drywell in which a combustible atmosphere is liable to be formed locally are taken out through a take-out pipeway to the outside of a reactor container and processed by a hydrogen-oxygen recombiner. Combustible gases in other areas of the drywell are also introduced to the lower area of the drywell and then taken-out externally for procession. Further, combustible gases in the suppression chamber are introduced by the opening of a vacuum breaking valve through a gas supply pipe to the lower area of the drywell and fluids in the drywell are stirred and diluted with fluids exhausted from the gas supply pipe. Disposition of such take-out pipeway and gas supply pipe can reduce the possibility of forming local combustible atmosphere to improve the integrity of the reactor container. (Kamimura, M.)

  17. Low emission turbulent technology for fuel combustion

    International Nuclear Information System (INIS)

    Finker, F. Z.; Kubyshkin, I. B.; Zakharov, B. Yu.; Akhmedov, D. B.; Sobchuk, Ch.

    1997-01-01

    The company 'POLITEKHENERGO' in co-operation and the Russian-Poland firm 'EnergoVIR' have performed investigations for modernization of the current existing boilers. A low emission turbulent technology has been used for the modernization of 10 industrial boilers. The reduction of NO x emissions is based on the following processes: 1) multistage combustion assured by two counter-deviated fluxes; 2) Some of the combustion facilities have an abrupt slope and a reduced air supply which leads to an intense separation of the fuel in the bottom part and a creation of a low-temperature combustion zone where the active restoration of the NO x takes part; 3) The influence of the top high-temperature zone on the NO x formation is small. Thus the 'sandwich' consisting of 'cold' and'hot' combustion layers provides a full rate combustion. This technique permits to: decrease of the NO x and CO x down to the European standard values;increase of the efficiency in 1-2%; obtain a stable coal combustion up to 97-98%; assure the large loading range (30 -100%); modernize and use the old boilers

  18. Sulfur equilibrium desulfurization of sulfur containing products of combustion

    International Nuclear Information System (INIS)

    Woodroffe, J.A.; Abichandani, J.S.

    1990-01-01

    This patent describes the method for the combustion of a carbon- and sulfur-containing fuel for substantially reducing emission of gaseous sulfur compounds formed during combustion of the fuel in a combustion zone. The zone having one or more fuel inlets and one or more oxidizer inlets, and having a combustion products outlet spaced therefrom, and having one or more inorganic sorbent inlets downstream of the fuel inlet(s) and oxidizer inlet(s) and upstream of the combustion products outlet

  19. Emission and combustion characteristics of multiple stage diesel combustion; Nidan nensho ni yoru diesel kikan no nensho to haishutsubutsu tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Hashizume, T; Miyamoto, T; Tsujimura, K [New A.C.E. Institute Co. Ltd., Tokyo (Japan); Kobayashi, S; Shimizu, K [Japan Automobile Research Institute, Tsukuba (Japan)

    1997-10-01

    A new concept of multiple stage diesel combustion was studied by means of engine test, combustion observation and numerical simulation, in order to reduce NOx emissions at high load conditions. With this concept, the premixed combustion occurs under the fuel lean conditions and the diffusion combustion occurs under the high temperature conditions. As seen in the result of combustion observation, a first stage combustion occurs with no luminous flame. A second stage combustion occurs with a luminous flame after very short ignition delay period. However the luminous flame is disappeared immediately. Because cylinder temperature is high, and hence soot oxidizes immediately. 5 refs., 11 figs., 1 tab.

  20. Combustion, detonation, shock waves. Proceedings of the Zel'dovich memorial - International conference on combustion. Volume 1

    International Nuclear Information System (INIS)

    Merzhanov, A.G.; Frolov, S.M.

    1995-01-01

    This book contains lectures by the experts in various fields of modern research in combustion, detonation and shock waves, presented at the Zel'dovich memorial - International conference on combustion dedicated to the 80-th birthday of academician Ya.B. Zel'dovich. There are eight chapters discussing the state-of-the-art in combustion kinetics, ignition and steady-state flame propagation, diffusion and heterogeneous combustion, turbulent combustion, unsteady combustion, detonation, combustion and detonation analogies, intense shock waves and extreme states of matter [ru

  1. con dietas suplementadas con Cromo-L-metionina

    Directory of Open Access Journals (Sweden)

    Ram\\u00F3n Garc\\u00EDa-Castillo

    2006-01-01

    Full Text Available Un total de 48 cerdos (Sus scrofa domesticus; 24 machos castrados y 24 hembras cruzados (Yorkshire, Hampshire, Duroc y Landrace de 3,5 a 4,0 meses de edad y 60,0 ± 5,0 kg PV en finalización. Se alimentaron con dietas isoproteícas (14,5 % PC e isoenergéticas (3.400 kcal EM/kg de MS, adicionadas con Cr-L-metionina (MiCroPlex® (0, 200, 400 y 600 ppb. El experimento tuvo una duración de 45 días y se realizó de agosto a noviembre del 2002 en las instalaciones de la Universidad Autónoma Agraria Antonio Narro, localizada en Saltillo, Coahuila, México. Al tener los animales aproximadamente 95 kg PV, se tomó muestra de 15 ml de sangre por cada animal para determinar la concentración de glucosa, ácido úrico, creatinina, urea, proteinas totales y colesterol. Se aplicó un diseño completamente al azar con arreglo factorial 2 x 4; dos para el factor sexo y cuatro para nivel de cromo. Los metabolitos en suero no fueron afectados (P>0,05 por el factor sexo. La glucosa en suero disminuyó (P<0,05 y el colesterol incrementó (P<0,05 con cromo en la dieta. Se concluye que el Cr incrementa el metabolismo de glucosa y disminuye el de colesterol, con lo cual puede haber energía disponible para síntesis de proteína la cual es necesaria para el crecimiento de los animales

  2. Rendimento, composição e análise sensorial do queijo minas frescal fabricado com leite de vacas mestiças alimentadas com diferentes volumosos Yield, composition and sensory analysis of Minas cheese made with milk from crossbred cows fed different roughages

    Directory of Open Access Journals (Sweden)

    Susi Cristina dos Santos Guimarães Martins

    2012-04-01

    Full Text Available Objetivou-se com este trabalho avaliar a qualidade físico-química e sensorial e o perfil de ácidos graxos do queijo minas frescal produzido com o leite de vacas mestiças alimentadas com dietas contendo quatro volumosos: canade-açúcar, silagem de sorgo, silagem de girassol e pastagem de Panicum maximum cv. Tanzânia. Foram avaliados o rendimento, a composição físico-química e o perfil de ácidos graxos. Também foi realizada a análise sensorial do queijo minas frescal e da composição físico-química do leite. Utilizaram-se oito vacas mestiças 1/2 Holandês/Gir, com período de lactação de 180 ± 12 dias, distribuídas em dois quadrados latinos 4 × 4, com quatro animais, quatro dietas e quatro períodos. Os períodos foram de 18 dias, sendo 15 dias de adaptação e três dias de coletas de dados. Após o processamento do queijo, foi feita análise microbiológica, físico-química e posteriormente análise sensorial. Amostras do queijo foram congeladas e analisadas quanto ao perfil de ácidos graxos. O teor de gordura do queijo foi maior para as dietas com cana-de-açúcar e silagem de girassol em relação à silagem de sorgo e ao pasto de Panicum maximum cv. Tanzânia, que não diferiram entre si. O queijo produzido a partir do leite de vacas alimentadas com silagem de girassol apresentou melhor perfil de ácidos graxos e índices de qualidade nutricional, maior proporção e melhor perfil de ácidos graxos insaturados. O rendimento do queijo foi igual para todas as dietas, independentemente do volumoso utilizado em sua composição. O queijo produzido com o leite de vacas alimentadas com silagem de girassol tem maior preferência pelos julgadores no teste de análise sensorial, especialmente quanto ao atributo aparência.The objective of this study was to evaluate the physical-chemical and sensory quality and fatty acid profile of Minas cheese produced from milk from crossbred cows fed diets with four roughages (sugar cane

  3. Recubrimiento de acero con polidopamina

    OpenAIRE

    Carrasco Rodríguez, Javier

    2013-01-01

    Se ha obtenido recubrimientos de polidopamina en acero mecánicamente resistentes y con tiempos de obtención relativamente pequeños a través de la polimerización de la dopamina bajo diferentes condiciones.

  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. Combustion and co-combustion of biomass in a bubbling fluidized bed boiler

    NARCIS (Netherlands)

    Khan, A.A.

    2007-01-01

    This PhD dissertation concerns the study of different aspects of biomass (co)-combustion in small-scale fluidized bed boilers for heat generation. The most renowned gaseous emissions from fluidized bed combustion, namely, CO and NO, are investigated with the help of experimental and theoretical

  6. Spray combustion of Jet-A and diesel fuels in a constant volume combustion chamber

    KAUST Repository

    Jing, Wei; Roberts, William L.; Fang, Tiegang

    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

  7. 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.

  8. The combustion behavior of diesel/CNG mixtures in a constant volume combustion chamber

    Science.gov (United States)

    Firmansyah; Aziz, A. R. A.; Heikal, M. R.

    2015-12-01

    The stringent emissions and needs to increase fuel efficiency makes controlled auto-ignition (CAI) based combustion an attractive alternative for the new combustion system. However, the combustion control is the main obstacles in its development. Reactivity controlled compression ignition (RCCI) that employs two fuels with significantly different in reactivity proven to be able to control the combustion. The RCCI concept applied in a constant volume chamber fuelled with direct injected diesel and compressed natural gas (CNG) was tested. The mixture composition is varied from 0 - 100% diesel/CNG at lambda 1 with main data collection are pressure profile and combustion images. The results show that diesel-CNG mixture significantly shows better combustion compared to diesel only. It is found that CNG is delaying the diesel combustion and at the same time assisting in diesel distribution inside the chamber. This combination creates a multipoint ignition of diesel throughout the chamber that generate very fast heat release rate and higher maximum pressure. Furthermore, lighter yellow color of the flame indicates lower soot production in compared with diesel combustion.

  9. Combustion tests with different pellet qualities

    International Nuclear Information System (INIS)

    Bachs, A.; Dahlstroem, J.E.; Persson, Henrik; Tullin, C.

    1999-05-01

    Eight different pellet qualities with the diameters 6, 8 and 10 mm, from eight different producers has been tested in three pellet burners and two pellet stoves. The objective was to investigate how different diameter affect the emissions of CO, OGC and NO x . Previous experience has indicated that the pellet diameter could have significant importance for the combustion. This was not verified in the study. It showed contradictory that the diameter has a minor effect on the combustion result. The study shows that different combustion equipment give different emission. For e g hydrocarbon emissions the difference is a factor 2.2 between the 'best' and the 'worst' equipment fired on full load. The difference increases to 2.7 with lower load. The choice of fuel has a big importance for the quality of the combustion. For hydrocarbons the emissions could in an extreme situation differ with a factor 25 between 'best' and 'worst' fuel. More normally the difference is about a factor of five. Nitrogen oxide emissions are to a major part related to the nitrogen contents in the fuel. The difference between the 'best' and 'worst' fuel is in the range of a factor two. Tests with the same fuel in different equipment gives a variation of 20-30%. The combustion result depends on both the pellet quality and the equipment and there is no fuel that is good in all equipment. The big variation in combustion results shows that there is a big indifference between fuels used for small scale heating Project report from the program: Small scale combustion of biofuels. 2 refs, 15 figs, 5 tabs

  10. Internal Heterogeneous Processes in Aluminum Combustion

    Science.gov (United States)

    Dreizin, E. L.

    1999-01-01

    This paper discusses the aluminum particle combustion mechanism which has been expanded by inclusion of gas dissolution processes and ensuing internal phase transformations. This mechanism is proposed based on recent normal and microgravity experiments with particles formed and ignited in a pulsed micro-arc. Recent experimental findings on the three stages observed in Al particle combustion in air and shows the burning particle radiation, trajectory (streak), smoke cloud shapes, and quenched particle interiors are summarized. During stage I, the radiation trace is smooth and the particle flame is spherically symmetric. The temperature measured using a three-color pyrometer is close to 3000 K. Because it exceeds the aluminum boiling point (2730 K), this temperature most likely characterizes the vapor phase flame zone rather than the aluminum surface. The dissolved oxygen content within particles quenched during stage I was below the detection sensitivity (about 1 atomic %) for Wavelength Dispersive Spectroscopy (WDS). After an increase in the radiation intensity (and simultaneous decrease in the measured color temperature from about 3000 to 2800 K) indicative of the transition to stage II combustion, the internal compositions of the quenched particles change. Both oxygen-rich (approx. 10 atomic %) and oxygen-lean (combustion behavior and the evolution of its internal composition, the change from the spherically symmetric to asymmetric flame shape occurring upon the transition from stage I to stage II combustion could not be understood based only on the fact that dissolved oxygen is detected in the particles. The connection between the two phenomena appeared even less significant because in earlier aluminum combustion studies carried in O2/Ar mixtures, flame asymmetry was not observed as opposed to experiments in air or O2/CO mixtures. It has been proposed that the presence of other gases, i.e., hydrogen, or nitrogen causes the change in the combustion regime.

  11. Large-eddy simulation of ethanol spray combustion using a finite-rate combustion model

    Energy Technology Data Exchange (ETDEWEB)

    Li, K.; Zhou, L.X. [Tsinghua Univ., Beijing (China). Dept. of Engineering Mechanics; Chan, C.K. [Hong Kong Polytechnic Univ. (China). Dept. of Applied Mathematics

    2013-07-01

    Large-eddy simulation of spray combustion is under its rapid development, but the combustion models are less validated by detailed experimental data. In this paper, large-eddy simulation of ethanol-air spray combustion was made using an Eulerian-Lagrangian approach, a subgrid-scale kinetic energy stress model, and a finite-rate combustion model. The simulation results are validated in detail by experiments. The LES obtained statistically averaged temperature is in agreement with the experimental results in most regions. The instantaneous LES results show the coherent structures of the shear region near the high-temperature flame zone and the fuel vapor concentration map, indicating the droplets are concentrated in this shear region. The droplet sizes are found to be in the range of 20-100{mu}m. The instantaneous temperature map shows the close interaction between the coherent structures and the combustion reaction.

  12. The Evaluation of Solid Wastes Reduction with Combustion System in the Combustion Chamber

    International Nuclear Information System (INIS)

    Prayitno; Sukosrono

    2007-01-01

    The evaluation of solid wastes reduction with combustion system is used for weight reduction factor. The evaluation was done design system of combustion chamber furnace and the experiment was done by burning a certain weight of paper, cloth, plastic and rubber in the combustion chamber. The evaluation of paper wastes, the ratio of wastes (paper, cloth, plastic and rubber) against the factor of weight reduction (%) were investigated. The condition was dimension of combustion chamber furnace = 0.6 X 0.9 X 1.20 X 1 m with combustion chamber and gas chamber and reached at the wastes = 2.500 gram, oxygen pressure 0.5 Bar, wastes ratio : paper : cloth : plastic : rubber = 55 : 10 : 30 : 5, the reduction factor = 6.36 %. (author)

  13. 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.

  14. 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.

  15. New technologies reducing emissions from combustion of biofuels

    International Nuclear Information System (INIS)

    Oravainen, H.

    1997-01-01

    In reducing CO 2 emissions, bioenergy will be the most important source of renewable energy in the next few decades. In principle, combustion of biomass is friendly to the environment because CO 2 released during combustion is recycled back into natural circulation. Biofuels normally contain little nitrogen and sulphur. However, depending on the combustion technology used, emissions may be quite high. This is true of combustion of biomass fuels in small appliances like wood stoves, fireplaces, small boilers etc. When fuels having high content of volatile matter are burnt in appliances using batch type combustion, the process is rather an unsteady-state combustion. Emissions of carbon monoxide, other combustible gases and particulates are quite difficult to avoid. With continuous combustion processes this is not normally a problem. This conference paper presents some means of reducing emissions from combustion of biofuels. 5 refs., 4 figs

  16. Plan de manejo ambiental planta distribuidora de combustibles líquidos derivados de los hidrocarburos

    OpenAIRE

    Gómez De La Torre Kusianovich, Raúl Tomás; Gómez De La Torre Kusianovich, Raúl Tomás

    2014-01-01

    Bachiller en Ingeniería Industrial graduado en la Universidad Nacional de Ingeniería, especializado en el área Producción Industrial en la fábrica de cubiertos, herramientas y autopartes INOXA SA con dos plantas industriales. Importante experiencia en Plantas de Ventas y Operaciones Comerciales en compañías del rubro de Hidrocarburos como Emcopesac, Petróleos del Perú, Mobil Oil del Perú, Multicamps y otras. Importante experiencia en Marketing y Ventas de combustibles y lubricantes. Amplia...

  17. Electrocatalizadores para pilas de combustible de membrana de intercambio protónico

    OpenAIRE

    Lázaro Elorri, María Jesús; Moliner Álvarez, Rafael; Calvillo Lamana, Laura; Pastor Ferrer, Elsa

    2008-01-01

    Electrocatalizadores para pilas de combustible de membrana de intercambio protónico. Procedimiento de obtención de un material de carbono mesoporoso (SMC) que comprende: la adición de sílice coloidal a un precursor polimérico de carbono; el curado térmico; el carbonizado del compuesto obtenido; lavado del compuesto carbonizado con ácido fluorhídrico (HF) o NaOH; y la oxidación del material lavado. Además la invención se refiere a un catalizador para pilas de combustibl...

  18. Viabilidad financiera de una estación de combustibles carretera a Cartago

    OpenAIRE

    Gatica Duarte, Mario Alberto

    2013-01-01

    Tesis de maestría -- Universidad de Costa Rica. Posgrado en Administración y Dirección de Empresas. Maestría Profesional en Administración y Dirección de Empresas con énfasis en Finanzas, 2013 Gatica Duarte, Mario Alberto VIABILIDAD FINANCIERA DE UNA ESTACIÓN DE COMBUSTIBLES CARRETERA A CARTAGO Programa de Posgrado en Administración y Dirección de Empresas.-San José, CR.: M. A. Gatica D., 2013. 158 h.- 33 il.- 46 refs. El objetivo general del trabajo es determinar si e...

  19. El biodiesel de aceite de higuerilla como combustible alternativo para motores diesel

    OpenAIRE

    ALIRIO BENAVIDES; PEDRO BENJUMEA; VESELINA PASHOVA

    2007-01-01

    En este artículo se presenta un estudio experimental sobre la producción y utilización del biodiesel de aceite de higuerilla. El máximo rendimiento de metilésteres en la reacción de transesterificación del aceite de higuerilla usado se obtiene bajo las siguientes condiciones: temperatura ambiente, una relación molar metanol/aceite de 9 y una concentración de catalizador de 0.8%. El biodiesel de aceite de higuerilla puede ser mezclado con el combustible diesel convencional derivado del petróle...

  20. EL BIODIESEL DE ACEITE DE HIGUERILLA COMO COMBUSTIBLE ALTERNATIVO PARA MOTORES DIESEL

    OpenAIRE

    BENAVIDES, ALIRIO; BENJUMEA, PEDRO; PASHOVA, VESELINA

    2007-01-01

    En este artículo se presenta un estudio experimental sobre la producción y utilización del biodiesel de aceite de higuerilla. El máximo rendimiento de metilésteres en la reacción de transesterificación del aceite de higuerilla usado se obtiene bajo las siguientes condiciones: temperatura ambiente, una relación molar metanol/aceite de 9 y una concentración de catalizador de 0.8%. El biodiesel de aceite de higuerilla puede ser mezclado con el combustible diesel convencional derivado del petróle...

  1. Prevention of criticality accidents. Fuel elements storage; Prevencion de accidentes de criticidad. Almacenamiento de elementos combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Canavese, S I; Capadona, N M

    1991-12-31

    Before the need to store fuel elements of the plate type MTR (Materials Testing Reactors), produced with enriched uranium at 20% in U235 for research reactors, it requires the design of a deposit for this purpose, which will give intrinsic security at a great extent and no complaints regarding its construction, is required. (Author). [Espanol] Partiendo de la necesidad de almacenar elementos combustibles tipo placa MTR (Materials Testing Reactors), producidos con uranio enriquecido al 20% en U235 para reactores de investigacion, se requiere el diseno de un deposito para tal fin que brinde esencialmente un alto grado de seguridad intrinseca y que no ofrezca complicaciones en cuanto a su construccion. (Autor).

  2. Impacts of Combustion Conditions and Photochemical Processing on the Light Absorption of Biomass Combustion Aerosol.

    Science.gov (United States)

    Martinsson, J; Eriksson, A C; Nielsen, I Elbæk; Malmborg, V Berg; Ahlberg, E; Andersen, C; Lindgren, R; Nyström, R; Nordin, E Z; Brune, W H; Svenningsson, B; Swietlicki, E; Boman, C; Pagels, J H

    2015-12-15

    The aim was to identify relationships between combustion conditions, particle characteristics, and optical properties of fresh and photochemically processed emissions from biomass combustion. The combustion conditions included nominal and high burn rate operation and individual combustion phases from a conventional wood stove. Low temperature pyrolysis upon fuel addition resulted in "tar-ball" type particles dominated by organic aerosol with an absorption Ångström exponent (AAE) of 2.5-2.7 and estimated Brown Carbon contributions of 50-70% to absorption at the climate relevant aethalometer-wavelength (520 nm). High temperature combustion during the intermediate (flaming) phase was dominated by soot agglomerates with AAE 1.0-1.2 and 85-100% of absorption at 520 nm attributed to Black Carbon. Intense photochemical processing of high burn rate flaming combustion emissions in an oxidation flow reactor led to strong formation of Secondary Organic Aerosol, with no or weak absorption. PM1 mass emission factors (mg/kg) of fresh emissions were about an order of magnitude higher for low temperature pyrolysis compared to high temperature combustion. However, emission factors describing the absorption cross section emitted per kg of fuel consumed (m(2)/kg) were of similar magnitude at 520 nm for the diverse combustion conditions investigated in this study. These results provide a link between biomass combustion conditions, emitted particle types, and their optical properties in fresh and processed plumes which can be of value for source apportionment and balanced mitigation of biomass combustion emissions from a climate and health perspective.

  3. Evaluación del funcionamiento de motores de combustión interna trabajando con biodiesel. // Evaluation of engine performance working with biodiesel.

    Directory of Open Access Journals (Sweden)

    R. Piloto Rodríguez

    2008-09-01

    Full Text Available En el presente trabajo se determinó la característica exterior de velocidad para dos motores de combustión internatrabajando con combustible biodiesel procedente de varias fuentes naturales y se comparó con la característica exterior develocidad de los motores originalmente trabajando con combustible diesel. Los motores fueron evaluados con variacionesde carga y velocidad. En uno de los motores ensayados fue determinada la presión en el interior de la cámara decombustión con el objetivo de evaluar el retardo de ignición. Fue observado que los motores trabajando con combustiblebiodiesel presentaban una disminución de la potencia efectiva y un aumento del consumo especifico de combustible. Seobservó una disminución del retardo de ignición cuando fue empleado el combustible biodiesel. También fue observadoque los gases contaminantes, excepto las emisiones de NOx y CO, disminuyen o permanecen constantes con el uso delbiocombustible.Palabras claves: Motores de combustión interna, biodiesel, emisiones, característica exterior de velocidad,retardo de ignición._____________________________________________________________________________Abstract:The engine outer velocity characterization for two engines was made working with biodiesel from different natural sources,and its performance was compared with the engine parameters using reference diesel. The engines were used varying loadand velocity. The ignition delay was obtained by measurement of in-cylinder pressure. A decrease in the effective powerand increase in the effective fuel consumption were observed in the engines when biodiesel is used. Biodiesel samplesshown shorter ignition delay than diesel. The pollutants emitted for the engine using biodiesel was lower than diesel, withthe exception of NOx and CO emissions.Key words: engine, biodiesel, emissions, outer velocity characteristic, ignition delay.

  4. Diffusion Driven Combustion Waves in Porous Media

    Science.gov (United States)

    Aldushin, A. P.; Matkowsky, B. J.

    2000-01-01

    Filtration of gas containing oxidizer, to the reaction zone in a porous medium, due, e.g., to a buoyancy force or to an external pressure gradient, leads to the propagation of Filtration combustion (FC) waves. The exothermic reaction occurs between the fuel component of the solid matrix and the oxidizer. In this paper, we analyze the ability of a reaction wave to propagate in a porous medium without the aid of filtration. We find that one possible mechanism of propagation is that the wave is driven by diffusion of oxidizer from the environment. The solution of the combustion problem describing diffusion driven waves is similar to the solution of the Stefan problem describing the propagation of phase transition waves, in that the temperature on the interface between the burned and unburned regions is constant, the combustion wave is described by a similarity solution which is a function of the similarity variable x/square root of(t) and the wave velocity decays as 1/square root of(t). The difference between the two problems is that in the combustion problem the temperature is not prescribed, but rather, is determined as part of the solution. We will show that the length of samples in which such self-sustained combustion waves can occur, must exceed a critical value which strongly depends on the combustion temperature T(sub b). Smaller values of T(sub b) require longer sample lengths for diffusion driven combustion waves to exist. Because of their relatively small velocity, diffusion driven waves are considered to be relevant for the case of low heat losses, which occur for large diameter samples or in microgravity conditions, Another possible mechanism of porous medium combustion describes waves which propagate by consuming the oxidizer initially stored in the pores of the sample. This occurs for abnormally high pressure and gas density. In this case, uniformly propagating planar waves, which are kinetically controlled, can propagate, Diffusion of oxidizer decreases

  5. Santiago, una ciudad con temor

    Directory of Open Access Journals (Sweden)

    Enrique Oviedo S.

    1999-04-01

    Full Text Available El objetivo general de este artículo es evaluar los efectos de la inseguridad ciudadana en el uso del espacio público. Dicha evaluación exige analizar dos relaciones que se establecen en el ámbito de la violencia: la relación entre victimización y percepción de inseguridad; y la que se establece entre actitudes sociales y resolución pacífica de conflictos nacionales. Para ello, se analizaron las variables victimización, percepción de inseguridad, uso del espacio físico, actitudes hacia el sistema institucional político y social y hacia la resolución de conflictos nacionales, y las posibles relaciones entre ellas. Los datos para realizar el estudio se obtuvieron por medio de una encuesta que se llevó a cabo con 1 200 personas de 18 y 70 años de edad residentes en la ciudad de Santiago. Los resultados indican que Santiago es una ciudad de habitantes con temor y que el aumento de la percepción de inseguridad de sus habitantes contrasta con el hecho de que las tasas de victimización se hayan mantenido, más o menos, constantes en los años que precedieron a la encuesta. El temor se relaciona con el abandono del espacio público físico y sociopolítico, así como con el refugio en los espacios y la vida privados. La actitud de resolver los conflictos por medios no pacíficos es frecuente y se asocia en mayor medida con la inseguridad, la actitud negativa hacia la democracia y la falta de expectativas sobre el futuro del país. Los resultados de este estudio respaldan la idea de que para superar el temor la gente tiende a adaptarse a la realidad adoptando una postura conformista, homogeneizando las creencias y los comportamientos, y sobreestimando la fuerza como medio para resolver las diferencias.

  6. Santiago, una ciudad con temor

    Directory of Open Access Journals (Sweden)

    Oviedo S. Enrique

    1999-01-01

    Full Text Available El objetivo general de este artículo es evaluar los efectos de la inseguridad ciudadana en el uso del espacio público. Dicha evaluación exige analizar dos relaciones que se establecen en el ámbito de la violencia: la relación entre victimización y percepción de inseguridad; y la que se establece entre actitudes sociales y resolución pacífica de conflictos nacionales. Para ello, se analizaron las variables victimización, percepción de inseguridad, uso del espacio físico, actitudes hacia el sistema institucional político y social y hacia la resolución de conflictos nacionales, y las posibles relaciones entre ellas. Los datos para realizar el estudio se obtuvieron por medio de una encuesta que se llevó a cabo con 1 200 personas de 18 y 70 años de edad residentes en la ciudad de Santiago. Los resultados indican que Santiago es una ciudad de habitantes con temor y que el aumento de la percepción de inseguridad de sus habitantes contrasta con el hecho de que las tasas de victimización se hayan mantenido, más o menos, constantes en los años que precedieron a la encuesta. El temor se relaciona con el abandono del espacio público físico y sociopolítico, así como con el refugio en los espacios y la vida privados. La actitud de resolver los conflictos por medios no pacíficos es frecuente y se asocia en mayor medida con la inseguridad, la actitud negativa hacia la democracia y la falta de expectativas sobre el futuro del país. Los resultados de este estudio respaldan la idea de que para superar el temor la gente tiende a adaptarse a la realidad adoptando una postura conformista, homogeneizando las creencias y los comportamientos, y sobreestimando la fuerza como medio para resolver las diferencias.

  7. 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

  8. Simulation of lean premixed turbulent combustion

    International Nuclear Information System (INIS)

    Bell, J; Day, M; Almgren, A; Lijewski, M; Rendleman, C; Cheng, R; Shepherd, I

    2006-01-01

    There is considerable technological interest in developing new fuel-flexible combustion systems that can burn fuels such as hydrogen or syngas. Lean premixed systems have the potential to burn these types of fuels with high efficiency and low NOx emissions due to reduced burnt gas temperatures. Although traditional Scientific approaches based on theory and laboratory experiment have played essential roles in developing our current understanding of premixed combustion, they are unable to meet the challenges of designing fuel-flexible lean premixed combustion devices. Computation, with its ability to deal with complexity and its unlimited access to data, has the potential for addressing these challenges. Realizing this potential requires the ability to perform high fidelity simulations of turbulent lean premixed flames under realistic conditions. In this paper, we examine the specialized mathematical structure of these combustion problems and discuss simulation approaches that exploit this structure. Using these ideas we can dramatically reduce computational cost, making it possible to perform high-fidelity simulations of realistic flames. We illustrate this methodology by considering ultra-lean hydrogen flames and discuss how this type of simulation is changing the way researchers study combustion

  9. Miniaturization limitations of rotary internal combustion engines

    International Nuclear Information System (INIS)

    Wang, Wei; Zuo, Zhengxing; Liu, Jinxiang

    2016-01-01

    Highlights: • Developed a phenomenological model for rotary internal combustion engines. • Presented scaling laws for the performance of micro rotary engines. • Adiabatic walls can improve the cycle efficiency but result in higher charge leakage. • A lower compression ratio can increase the efficiency due to lower mass losses. • Presented possible minimum engine size of rotary internal combustion engines. - Abstract: With the rapid development of micro electro-mechanical devices, the demands for micro power generation systems have significantly increased in recent years. Traditional chemical batteries have energy densities much lower than hydrocarbon fuels, which makes internal-combustion-engine an attractive technological alternative to batteries. Micro rotary internal combustion engine has drawn great attractions due to its planar design, which is well-suited for fabrication in MEMS. In this paper, a phenomenological model considering heat transfer and mass leakage has been developed to investigate effects of engine speed, compression ratio, blow-by and heat transfer on the performance of micro rotary engine, which provide the guidelines for preliminary design of rotary engine. The lower possible miniaturization limits of rotary combustion engines are proposed.

  10. Combustion of environmentally altered molybdenum trioxide nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Kevin; Pantoya, Michelle L. [Mechanical Engineering Department, Texas Tech University, 2500 Broadway, Lubbock, TX 79409 (United States)

    2006-06-15

    Nanocomposite thermite mixtures are currently under development for many primer applications due to their high energy densities, high ignition sensitivity, and low release of toxins into the environment. However, variability and inconsistencies in combustion performance have not been sufficiently investigated. Environmental interactions with the reactants are thought to be a contributing factor to these variabilities. Combustion velocity experiments were conducted on aluminum (Al) and molybdenum trioxide (MoO{sub 3}) mixtures to investigate the role of environmental interactions such as light exposure and humidity. While the Al particles were maintained in an ambient, constant environment, the MoO{sub 3} particles were exposed to UV or fluorescent light, and highly humid environments. Results show that UV and fluorescent lighting over a period of days does not significantly contribute to performance deterioration. However, a humid environment severely decreases combustion performance if the oxidizer particles are not heat-treated. Heat treatment of the MoO{sub 3} greatly increases the material's ability to resist water absorption, yielding more repeatable combustion performance. This work further quantifies the role of the environment in the decrease of combustion performance of nanocomposites over time. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  11. Fuel and Additive Characterization for HCCI Combustion

    International Nuclear Information System (INIS)

    Aceves, S M; Flowers, D; Martinez-Frias, J; Espinosa-Loza, F; Pitz, W J; Dibble, R

    2003-01-01

    This paper shows a numerical evaluation of fuels and additives for HCCl combustion. First, a long list of candidate HCCl fuels is selected. For all the fuels in the list, operating conditions (compression ratio, equivalence ratio and intake temperature) are determined that result in optimum performance under typical operation for a heavy-duty engine. Fuels are also characterized by presenting Log(p)-Log(T) maps for multiple fuels under HCCl conditions. Log(p)-Log(T) maps illustrate important processes during HCCl engine operation, including compression, low temperature heat release and ignition. Log(p)-Log(T) diagrams can be used for visualizing these processes and can be used as a tool for detailed analysis of HCCl combustion. The paper also includes a ranking of many potential additives. Experiments and analyses have indicated that small amounts (a few parts per million) of secondary fuels (additives) may considerably affect HCCl combustion and may play a significant role in controlling HCCl combustion. Additives are ranked according to their capability to advance HCCl ignition. The best additives are listed and an explanation of their effect on HCCl combustion is included

  12. 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.

  13. Neutrophil Leukocyte: Combustive Microbicidal Action and Chemiluminescence

    Directory of Open Access Journals (Sweden)

    Robert C. Allen

    2015-01-01

    Full Text Available Neutrophil leukocytes protect against a varied and complex array of microbes by providing microbicidal action that is simple, potent, and focused. Neutrophils provide such action via redox reactions that change the frontier orbitals of oxygen (O2 facilitating combustion. The spin conservation rules define the symmetry barrier that prevents direct reaction of diradical O2 with nonradical molecules, explaining why combustion is not spontaneous. In burning, the spin barrier is overcome when energy causes homolytic bond cleavage producing radicals capable of reacting with diradical O2 to yield oxygenated radical products that further participate in reactive propagation. Neutrophil mediated combustion is by a different pathway. Changing the spin quantum state of O2 removes the symmetry restriction to reaction. Electronically excited singlet molecular oxygen (O2*1 is a potent electrophilic reactant with a finite lifetime that restricts its radius of reactivity and focuses combustive action on the target microbe. The resulting exergonic dioxygenation reactions produce electronically excited carbonyls that relax by light emission, that is, chemiluminescence. This overview of neutrophil combustive microbicidal action takes the perspectives of spin conservation and bosonic-fermionic frontier orbital considerations. The necessary principles of particle physics and quantum mechanics are developed and integrated into a fundamental explanation of neutrophil microbicidal metabolism.

  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. 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.

  16. 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.

  17. Evaluación del consumo de los combustibles (GM, E-10 y GNC en un vehículo de combustión interna de servicio público en la ciudad de Cali - Colombia

    Directory of Open Access Journals (Sweden)

    Luis Felipe Granada Aguirre

    2006-01-01

    Full Text Available En este documento se muestran los rendimientos (consumo de combustible obtenidos por un vehículo de combustión interna de servicio público que fue adaptado para funcionar con diferentes tipos de combustibles como Gasolina Motor (GM, mezcla de GM con 10% de etanol (E-10 y Gas Natural Comprimido (GNC. El vehículo utilizado fue un HYUNDAI ATOS modelo 2005, motor 1000 cc, conducido por un adulto de 23 años de edad. El periodo de evaluación fue entre junio 13 de 2005 y abril 13 de 2006.

  18. SCR at bio fuel combustion

    International Nuclear Information System (INIS)

    Andersson, Christer; Odenbrand, I.; Andersson, L.H.

    1998-10-01

    In this project the cause for and the extent of catalyst deactivation has been investigated when using 100 % wood as fuel. The trend of deactivation has been studied as a function of the flue gas temperature, the type of catalyst and the type of combustion technique used. The field tests have been performed in the CFB boiler in Norrkoeping, firing forest residues, and in the boiler in Jordbro, firing pulverized wood (PC). Samples of four different commercial catalyst types have been exposed to flue gas in a test rig connected to the convection section of the boiler. The samples have been analysed at even time intervals. The results after 2 100 hours show a large difference in deactivation trend between the two plants; when using a conventional honeycomb catalyst 80 % of the original activity remains in the CFB boiler but only 20 % remains in the PC boiler. The deactivation in the CFB boiler is about 3 - 4 times faster than what is expected for a conservative design for a coal fired boiler. The results show that the general deactivation trend is similar for the plate and the honeycomb catalyst types. With a catalyst optimised for bio fuels the deactivation rate was about 2/3 compared with a conventional catalyst. At an operating temperature of 315 deg C the deactivation was not as rapid as at 370 deg C. The amount of easily dissolved potassium increases on the surface of the catalyst, especially in the PC boiler, and this is probably the reason for the deactivation. The total amount of potassium in the flue gas is about 5 times higher in the CFB boiler compared with the PC boiler. This indicates that only a certain form of potassium attacks the catalyst and that the total alkali content of the fuel is not a good indicator of the deactivation tendency. The potassium on the catalyst dissolves easily in both water and sulphuric acid. A wash of deactivated catalyst samples with water resulted in higher activity than for the fresh samples if the washing was supplemented

  19. 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. .

  20. Effects of stepwise gas combustion on NOx generation

    International Nuclear Information System (INIS)

    Woperane Seredi, A.; Szepesi, E.

    1999-01-01

    To decrease NO x emission from gas boilers, the combustion process of gas has been modified from continuous combustion to step-wise combustion. In this process the combustion temperature, the temperature peaks in the flame, the residence time of combustion products in the high-temperature zone and the oxygen partial pressure are changed advantageously. Experiments were performed using multistage burners, and the NO x emission was recorded. It was found that the air factor of the primary combustion space has a determining effect on the NO x reduction. (R.P.)

  1. Identification of combustion intermediates in low-pressure premixed pyridine/oxygen/argon flames.

    Science.gov (United States)

    Tian, Zhenyu; Li, Yuyang; Zhang, Taichang; Zhu, Aiguo; Qi, Fei

    2008-12-25

    Combustion intermediates of two low-pressure premixed pyridine/oxygen flames with respective equivalence ratios of 0.56 (C/O/N = 1:4.83:0.20) and 2.10 (C/O/N = 1:1.29:0.20) have been identified with tunable synchrotron vacuum ultraviolet (VUV) photoionization and molecular-beam mass spectrometry techniques. About 80 intermediates in the rich flame and 60 intermediates in the lean flame, including nitrogenous, oxygenated, and hydrocarbon intermediates, have been identified by measurements of photoionization mass spectra and photoionization efficiency spectra. Some radicals and new nitrogenous intermediates are identified in the present work. The experimental results are useful for studying the conversion of volatile nitrogen compounds and understanding the formation mechanism of NO(x) in flames of nitrogenous fuels.

  2. 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.

  3. Understanding Combustion Processes Through Microgravity Research

    Science.gov (United States)

    Ronney, Paul D.

    1998-01-01

    A review of research on the effects of gravity on combustion processes is presented, with an emphasis on a discussion of the ways in which reduced-gravity experiments and modeling has led to new understanding. Comparison of time scales shows that the removal of buoyancy-induced convection leads to manifestations of other transport mechanisms, notably radiative heat transfer and diffusional processes such as Lewis number effects. Examples from premixed-gas combustion, non-premixed gas-jet flames, droplet combustion, flame spread over solid and liquid fuels, and other fields are presented. Promising directions for new research are outlined, the most important of which is suggested to be radiative reabsorption effects in weakly burning flames.

  4. Starting procedure for internal combustion vessels

    Science.gov (United States)

    Harris, Harry A.

    1978-09-26

    A vertical vessel, having a low bed of broken material, having included combustible material, is initially ignited by a plurality of ignitors spaced over the surface of the bed, by adding fresh, broken material onto the bed to buildup the bed to its operating depth and then passing a combustible mixture of gas upwardly through the material, at a rate to prevent back-firing of the gas, while air and recycled gas is passed through the bed to thereby heat the material and commence the desired laterally uniform combustion in the bed. The procedure permits precise control of the air and gaseous fuel mixtures and material rates, and permits the use of the process equipment designed for continuous operation of the vessel.

  5. Processing of hydroxyapatite obtained by combustion synthesis

    International Nuclear Information System (INIS)

    Canillas, M.; Rivero, R.; García-Carrodeguas, R.; Barba, F.; Rodríguez, M.A.

    2017-01-01

    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. [es

  6. 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....

  7. 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....

  8. 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...

  9. Numerical simulation of turbulent combustion: Scientific challenges

    Science.gov (United States)

    Ren, ZhuYin; Lu, Zhen; Hou, LingYun; Lu, LiuYan

    2014-08-01

    Predictive simulation of engine combustion is key to understanding the underlying complicated physicochemical processes, improving engine performance, and reducing pollutant emissions. Critical issues as turbulence modeling, turbulence-chemistry interaction, and accommodation of detailed chemical kinetics in complex flows remain challenging and essential for high-fidelity combustion simulation. This paper reviews the current status of the state-of-the-art large eddy simulation (LES)/prob-ability density function (PDF)/detailed chemistry approach that can address the three challenging modelling issues. PDF as a subgrid model for LES is formulated and the hybrid mesh-particle method for LES/PDF simulations is described. Then the development need in micro-mixing models for the PDF simulations of turbulent premixed combustion is identified. Finally the different acceleration methods for detailed chemistry are reviewed and a combined strategy is proposed for further development.

  10. 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.

  11. pacientes con insuficiencia renal terminal

    Directory of Open Access Journals (Sweden)

    Karen Herrera Herrera

    2011-01-01

    Full Text Available La presente investigación fundamenta en la clínica psicoanalítica el estudio de dos casos de tres personas diagnosticadas con IRT que reciben tratamiento de hemodiálisis, en razón a que dadas las características y el aumento de los reportes que se presentan, ya esto se considera un problema de salud pública. El objetivo principal es describir las características dinámicas del proceso de duelo en pacientes con IRT en un centro de terapia renal de la ciudad de Cartagena. El procedimiento metodológico empleó un diseño de tipo cualitativo; la investigación se desarrolló con un diseño clínico mediante el estudio de casos, y fundamentada en la hermenéutica psicoanalítica. Todo esto respaldado en la historia clínica, la entrevista semiestructurada individual y familiar, los test proyectivos, test del dibujo de la figura humana Machover y TAT de Murray, para la debida integración de los análisis. Se concluye que predominan funciones fallidas de los progenitores y que son individuos provenientes de familias psicosomáticas, que utilizan la enfermedad para obtener un beneficio secundario.

  12. con bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Adriana Mora Antó

    2005-01-01

    Full Text Available Esta investigación dio cuenta de la relación entre el estilo de funcionamiento familiar, los patrones de crianza y las edades de desarrollo evolutivo en niños, nacidos con bajo peso. El estudio descriptivo correlacional se realizó con 41 niños y sus madres, aplicándose cuestionarios sobre funcionamiento familiar, prácticas de crianza y desarrollo infantil. Los resultados señalaron la existencia de un funcionamiento familiar caracterizado por una cohesión amalgamada y una adaptabilidad caótica, una disciplina complaciente, falta de control y de límites claros en la díada madre-hijo. Se trataba de familias monoparentales, donde la temprana edad de concepción, el madresolterismo y el apoyo de la familia extensa eran constantes. Las edades evolutivas registradas indicaron un desarrollo inferior a la edad cronológica, en la mayor parte de los casos; sin embargo, éstas tendieron a ser superiores al compararlas con la edades reales de los infantes. No se encontró una correlación estadísticamente significativa entre la edad de desarrollo y los diferentes factores del funcionamiento familiar para algunos de los rangos de edad considerados; sin embargo, no se lo descartó por completo, especialmente en lo referente al optimismo familiar

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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)

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

    KAUST Repository

    An, Yanzhao; Jaasim, Mohammed; Vallinayagam, R.; Vedharaj, S.; Im, Hong G.; Johansson, Bengt.

    2017-01-01

    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.

  19. Heavy metals behaviour during mono-combustion and co-combustion of sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, M. Helena; Abelha, Pedro; Olieveira, J.F. Santos; Gulyurtlu, Ibrahim; Cabrita, Isabel [INETI-DEECA, Lisboa (Portugal)

    2005-03-01

    This paper presents the study of the combustion of granular dry sewage sludge performed on a pilot fluidized bed system. The results of mono-combustion of sludge and co-combustion with coal were compared with those of coal combustion for ash partitioning, the formation of gaseous pollutants and heavy metals behaviour. It was found that the mineral matter of sludge was essentially retained as bottom ashes. The production of fines ashes was small during the mono-combustion due to the tendency of coal to produce fine ashes which also contained unburned char. The degree of heavy metal volatilization was found to be slightly higher during co-combustion than in mono-combustion; however, most of them were retained in ashes and their emissions were found to be below the regulated levels. Hg was completely volatilized; however, during combustion trials involving coal it was captured by cyclone ashes at temperatures below 300 deg C. During sludge mono-combustion the retention of Hg in cyclone ashes containing low LOI was not enough to decrease emissions below the regulated levels; hence, it is necessary to install dedicated flue gas treatment for Hg removal. The leachability and ecotoxicity of sludge and ashes was compared with the new regulatory limits for landfill disposal in the EU. It was found that the release of organic matter and heavy metals found in the sludge was low from granular bed ashes; hence, except for sulphate release, bed ashes were converted into inert and non-ecotoxic materials. Ashes from test with limestone and cyclone ashes seemed to be more problematic because of pH effects and contamination with steel corrosion products. The recovery and reutilization of sludge bed ashes could, therefore, be possible, as long as the release of sulphate do not interfere with the process.

  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. Nordic seminar on biomass gasification and combustion

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    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.

  2. Effects of combustible stacking in large compartments

    DEFF Research Database (Denmark)

    Gentili, Filippo; Giuliani, Luisa; Bontempi, Franco

    2013-01-01

    This paper focuses on the modelling of fire in case of various distributions of combustible materials in a large compartment. Large compartments often represent a challenge for structural fire safety, because of lack of prescriptive rules to follow and difficulties of taking into account the effect...... 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...

  3. Reaction-diffusion pulses: a combustion model

    International Nuclear Information System (INIS)

    Campos, Daniel; Llebot, Josep Enric; Fort, Joaquim

    2004-01-01

    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

  4. 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.

  5. Thermogravimetric analysis of combustible waste components

    DEFF Research Database (Denmark)

    Munther, Anette; Wu, Hao; Glarborg, Peter

    In order to gain fundamental knowledge about the co-combustion of coal and waste derived fuels, the pyrolytic behaviors of coal, four typical waste components and their mixtures have been studied by a simultaneous thermal analyzer (STA). The investigated waste components were wood, paper, polypro......In order to gain fundamental knowledge about the co-combustion of coal and waste derived fuels, the pyrolytic behaviors of coal, four typical waste components and their mixtures have been studied by a simultaneous thermal analyzer (STA). The investigated waste components were wood, paper...

  6. 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.

  7. Selected parameters of maize straw briquettes combustion

    Directory of Open Access Journals (Sweden)

    Kraszkiewicz Artur

    2018-01-01

    Full Text Available An analysis of the process of burning briquettes made of maize straw was performed. A number of traits have been evaluated, including physical characteristics of the fuel through parameters describing combustion kinetics as well as products and combustion efficiency. The study was conducted in a grate boiler, during which the differentiating factor was the air velocity flowing to the boiler. It was observed that the obtained values of the considered parameters were different, particularly temperature of the flue gas and the amount of CO and SO2 in the flue gas.

  8. Nordic seminar on biomass gasification and combustion

    International Nuclear Information System (INIS)

    1993-01-01

    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

  9. THE COMBUSTION CHARACTERISTICS OF LIGNITE BLENDS

    Institute of Scientific and Technical Information of China (English)

    Cheng Jun; Zhou Junhu; Cao Xinyu; Cen Kefa

    2000-01-01

    The combustion characteristics of lignite blends were studied with a thermogravimetric analyzer (t.g.a.), at constant heating rate.The characteristic temperatures were determined from the burning profiles.It was found that the characteristic times of combustion reaction moved forward, the ignition temperature dropped and the burnout efficiency slightly changed when blending lignites.The characteristic parameters of blends could not be predicted as a linear function of the average values of the individual lignites.when blending with less reactive coal, the ignition and burnout characteristics of lignite turned worse.

  10. Gas Emissions in Combustion of Biofuel

    Directory of Open Access Journals (Sweden)

    Vitázek Ivan

    2014-10-01

    Full Text Available Nowadays, biomass or more precisely biofuel is more and more being exploited as a substitute for fossil fuels for heating as well as for example for heating a drying environment. This contribution focuses on assessing a heat source by combusting various types of solid biofuels. It is a boiler VIGAS 25 with AK 2000 regulation for heating a family house. Gaseous emissions were measured using a device TESTO 330-2LL. Firewood, peat briquettes, bark briquettes and hardwood briquettes were burnt. Results of experimental measurements concerning the production of gaseous emissions are processed in tables and graphs depending on boiler performance and combustion time.

  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...

  12. Fundamental Study of Single Biomass Particle Combustion

    DEFF Research Database (Denmark)

    Momenikouchaksaraei, Maryam

    This thesis is a comprehensive study of single biomass particle combustion. The effect of particle shape and size and operating conditions on biomass conversion characteristics were investigated experimentally and theoretically. The experimental samples were divided in two groups: particles...... well-defined conditions, and the complete combustion processes were recorded as video sequences by a CCD camera installed in the set-up. One of the project objectives is to simulate conditions reasonably close to the conditions in a power plant boiler, i.e., reasonably high temperatures (up to 1600°C...

  13. 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...

  14. 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.

  15. Efficient catalytic combustion in integrated micropellistors

    International Nuclear Information System (INIS)

    Bársony, I; Ádám, M; Fürjes, P; Dücső, Cs; Lucklum, R; Hirschfelder, M; Kulinyi, S

    2009-01-01

    This paper analyses two of the key issues of the development of catalytic combustion-type sensors: the selection and production of active catalytic particles on the micropellistor surface as well as the realization of a reliable thermal conduction between heater element and catalytic surface, for the sensing of temperature increase produced by the combustion. The report also demonstrates that chemical sensor product development by a MEMS process is a continuous struggle for elimination of all uncertainties influencing reliability and sensitivity of the final product

  16. 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.

  17. Estudio comparativo de las diferentes tecnologías de celdas de combustible

    Directory of Open Access Journals (Sweden)

    Alvarado-Flores, J.

    2013-06-01

    combustible. Además, se comparan las características tecno-económicas de los vehículos que funcionan con celdas de combustible a partir de hidrógeno (Fuel Cell Vehicle, FVC y vehículos con motor de combustión interna (Internal Combustion Engine Vehicle, ICEV. Los resultados indican que los sistemas de celdas de combustibles tienen un diseño simple, confiabilidad alta, funcionamiento silencioso, alta eficiencia y menor impacto ambiental. El objetivo de este artículo, es servir de una conveniente referencia sobre la generación de energía a partir de las celdas de combustible.

  18. Transesterificación del aceite de palma con metanol por medio de una catálisis heterogénea empleando un catalizador ácido

    Directory of Open Access Journals (Sweden)

    Lina Marcela Riveros Santamaría

    2006-11-01

    Full Text Available La transesterificación del aceite de palma crudo con metanol se llevó a cabo en un reactor Batch bajo un rango de temperatura de 129-140°C y una presión manométrica de 6.4-9.4 bares, en presencia de Oxido de Zinc. Los factores estudiados fueron la cantidad de catalizador y la relación molar aceite:metanol alimentadas a la reacción La producción de esteres metílicos se incrementó al aumentar la cantidad de Óxido de Zinc, mientras que la relación aceite:metanol óptima fue de 1:30. El mayor rendimiento de esteres alcanzado fue de 38.75%. Los valores de Densidad, Viscosidad y Punto de nube determinados más cercanos a los estándar para Biodiesel fueron 0.871 gr/ml, 3.77 cSt y 12°C respectivamente./ Transesterification of crude palm oil with methanol was carried out using a Batch reactor under a range of temperature from 129 to 140°C, and a manometric pressure of 6.4-9.4 bars, in the presence of Zinc Oxide. The studied factors were the amount of catalyst and the molar relation of oil:methanol in the reaction. The production of methyl esters was increased with the amount of Zinc Oxide, while the optimal molar relation oil:methanol was 1:30. The greatest yield of methyl esters achieved was 38.75%. The closest Density, Viscosity and Cloud point values to Biodiesel standard values were 0.871 gr/ml, 3.77 cSt y 12°C respectively.

  19. Combustion synthesis and structural characterization of Li–Ti mixed

    Indian Academy of Sciences (India)

    Combustion synthesis and structural characterization of Li–Ti mixed nanoferrites ... were prepared by combustion method at lower temperatures compared to the ... first time at low temperatures, using PEG which acts as a new fuel and oxidant.

  20. combustion properties of briquettes produced from maize cob

    African Journals Online (AJOL)

    joke

    2014-03-01

    Mar 1, 2014 ... were densified into briquettes using starch as binder. Combustion related ... Keywords: Briquette, maize cob, combustion properties, mesh sizes, binding agent ... smaller space requirement for storage (Yaman et al., 2000 and ...

  1. 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.

  2. Combustion synthesis and structural characterization of Li–Ti mixed ...

    Indian Academy of Sciences (India)

    pared by combustion method at lower temperatures compared to the conventional high temperature sintering for ... Li–Ti mixed ferrites; combustion synthesis; hysteresis. 1. ... Quantum model - VSM 6000) at an applied field of ±10 kOe.

  3. Improved Combustion Products Monitor for the ISS, Phase II

    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...

  4. Improved Combustion Products Monitor for the ISS, Phase I

    Data.gov (United States)

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

  5. Determination of (BTEX) of the gasoline's combustion in Ecuador

    International Nuclear Information System (INIS)

    Garcia, Nelson; Insuasti, Alicia

    1998-01-01

    The contents of benzene, toluene, ethyl benzene and xylenes (BTEX) were determined and quantified in the gasoline's combustion on an internal combustion engine. Gas chromatography with flame ionization detector were used for chemical determinations

  6. 78 FR 54606 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2013-09-05

    ... Combustion Engines; New Source Performance Standards for Stationary Internal Combustion Engines AGENCY... hazardous air pollutants for stationary reciprocating internal combustion engines and the standards of performance for stationary internal combustion engines. Subsequently, the EPA received three petitions for...

  7. Observación de la fracción de agua líquida en pilas de combustible tipo PEM de cátodo abierto

    OpenAIRE

    Luna, Julio; Costa Castelló, Ramón

    2017-01-01

    En este trabajo se diseña un observador no-lineal basado en modos deslizantes para la estimación de la fracción de agua líquida en una pila de combustible tipo PEM de cátodo abierto. La pila de combustible se modela con dos estados dinámicos: la temperatura de la pila y la saturación de agua líquida. La estrategia de observación se valida en simulación mediante un ciclo de conducción ARTEMIS.

  8. Biorremediación para la degradación de hidrocarburos totales presentes en los sedimentos de una estación de servicio de combustible

    OpenAIRE

    Ñustez Cuartas, Diana Cristina

    2012-01-01

    En la presente investigación se evaluó el efecto de la Bioaumentación y Bioestimulación de sedimentos contaminados con hidrocarburos de la Estación de Servicio de Combustible INTEGRA de Dosquebradas – Risaralda - Colombia, estos sedimentos son producto del mantenimiento de las unidades de tratamiento de aguas residuales industriales, como son: la trampa de grasa, canales perimetrales de la zona de distribución y/o venta del combustible, canales perimetrales de la zona de llenado de tanques de...

  9. 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.

  10. Furnace for degasification and gasification of combustibles rich in ashes

    Energy Technology Data Exchange (ETDEWEB)

    1952-05-13

    A furnace is described for the degasification and the gasification of combustibles rich in ashes with continuous-functioning vertical chambers of transversal rectangular sections in which the washing gas flows from one side to the other, traversing the combustible, characterized by the fact that the height of the combustible surrounded by the washing gas stays in a proportion higher than 10:1 to the thickness of the width of combustible.

  11. 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.)

  12. 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

  13. Boris Novozhilov: Life and contribution to the physics of combustion

    Science.gov (United States)

    Novozhilov, Vasily

    2018-04-01

    Professor Boris Novozhilov (1930-2017) passed away on February 19th, 2017 in Moscow. The present paper provides brief account of his life and contributions to the physics of combustion. From extensive scientific legacy left by Boris, several major achievements are discussed here: Zeldovich-Novozhilov (ZN) theory of unsteady solid propellant combustion, contributions to thermal explosion theory, the theory of spin combustion, discovery of propellant combustion transition to chaotic regimes through Feigenbaum period bifurcation scenario.

  14. Combustion and Ignition Studies of Nanocomposite Energetic Materials

    Science.gov (United States)

    2010-12-14

    Characterization of a gas burner to simulate a propellant flame and evaluate aluminum particle combustion,” M. Jackson, M. L. Pantoya and W. Gill, Combustion...of a gas burner to simulate a propellant flame and evaluate aluminum particle combustion,” M. Jackson, M. L. Pantoya and W. Gill, Combustion and...changes in parameters such as particle size. The LFA measures these properties for bulk powders, consolidated pellets or even liquid mediums and is

  15. Development of a NO/x/-free combustion system

    Science.gov (United States)

    Sadakata, M.; Furusawa, T.; Kunii, D.; Imagawa, M.; Nawada, M.

    1980-04-01

    The development of a NO(x)-free combustion-heating system realizing both pollution control and energy savings is described. An experiment was carried out by using a small model plant. The system consists of a combustion furnace and a new-type multifunctional heat exchanger. The heat exchanger is a rotary continuous type designed for soot collection and for catalytic combustion of CO and H2 as well as for preheating combustion air.

  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. 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.

  18. NITROUS OXIDE EMISSIONS FROM FOSSIL FUEL COMBUSTION

    Science.gov (United States)

    The role of coal combustion as a significant global source of nitrous oxide (N2O) emissions was reexamined through on-line emission measurements from six pulverized-coal-fired utility boilers and from laboratory and pilot-scale combustors. The full-scale utility boilers yielded d...

  19. NOx Emission Reduction by Oscillating Combustion

    Energy Technology Data Exchange (ETDEWEB)

    None

    2005-09-01

    This project focuses on a new technology that reduces NOx emissions while increasing furnace efficiency for both air- and oxygen-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.

  20. Plutonium, nuclear fuel; Le plutonium, combustible nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Grison, E [Commissariat a l' Energie Atomique, Fontenay aux Roses (France). Centre d' Etudes Nucleaires, Saclay

    1960-07-01

    A review of the physical properties of metallic plutonium, its preparation, and the alloys which it forms with the main nuclear metals. Appreciation of its future as a nuclear fuel. (author) [French] Apercu sur les proprietes physiques du plutonium metallique, sa preparation, ses alliages avec les principaux metaux nucleaires. Consideration sur son avenir en tant que combustible nucleaire. (auteur)

  1. Steam-moderated oxy-fuel combustion

    International Nuclear Information System (INIS)

    Seepana, Sivaji; Jayanti, Sreenivas

    2010-01-01

    The objective of the present paper is to propose a new variant of the oxy-fuel combustion for carbondioxide (CO 2 ) sequestration in which steam is used to moderate the flame temperature. In this process, pure oxygen is mixed with steam and the resulting oxidant mixture is sent to the boiler for combustion with a fossil fuel. The advantage of this method is that flue gas recirculation is avoided and the volumetric flow rates through the boiler and auxiliary components is reduced by about 39% when compared to the conventional air-fired coal combustion power plant leading to a reduction in the size of the boiler. The flue gas, after condensation of steam, consists primarily of CO 2 and can be sent directly for compression and sequestration. Flame structure analysis has been carried out using a 325-step reaction mechanism of methane-oxidant combustion to determine the concentration of oxygen required to ensure a stable flame. Thermodynamic exergy analysis has also been carried out on SMOC-operated CO 2 sequestration power plant and air-fired power plant, which shows that though the gross efficiency increases the absolute power penalty of ∼8% for CO 2 sequestration when compared to air-fired power plant.

  2. On the influence of steam on combustion

    NARCIS (Netherlands)

    Derksen, M.A.F.

    2005-01-01

    In this thesis, a numerical simulation study is presented of the influence of steam on premixed and partially premixed combustion. Both laminar (premixed) and turbulent (partially premixed) calculations are presented. The laminar calculations were performed using a detailed chemical mechanism and

  3. Quality Determination of Biomass for Combustion

    DEFF Research Database (Denmark)

    Liu, Na; Jørgensen, Uffe; Lærke, Poul Erik

    2013-01-01

    A high content of minerals in biomass feedstock may cause fouling, slagging, and corrosion in the furnace during combustion. Here, a new pressurized microwave digestion method for biomass digestion prior to elemental analysis is presented. This high-throughput method is capable of processing...

  4. Combustion Kinetic Studies of Gasolines and Surrogates

    KAUST Repository

    Javed, Tamour

    2016-01-01

    . These measurements were performed in shock tubes and rapid compression machines over a wide range of experimental conditions (650 – 1250 K, 10 – 40 bar) relevant to internal combustion engines. Using the measured the data and chemical kinetic analyses, the surrogate

  5. Internal combustion engines history - a review

    International Nuclear Information System (INIS)

    Gaviria Rios, Jorge Enrique; Mora Guzman, Jorge Hernan; Agudelo, John Ramiro

    2002-01-01

    In this article, a chronological analysis of the technologies and events that any way influenced in the evolution of the internal combustion engine is done everything it through the observation of the works carried out for scientific empiric and engineers whose technical and conceptual value meant the motivation of other people for the search of a better development in this engineering field

  6. Wood combustion and NOx formation control

    International Nuclear Information System (INIS)

    Tewksbury, C.

    1991-01-01

    The control of wood combustion on stoker fed grates for optimum efficiency and the limiting of NO x (oxides of nitrogen) formation are not necessarily contradictory. This paper presents a matrix of air/fuel ratio control options, then discusses simple on-line monitoring techniques and the importance of operator training and alertness. The significance of uniform fuel feed and air distribution is emphasized. The relationships between combustion control and NO x formation are outlined both in theory and as tested. The experience of the McNeil Generating Station (the largest wood-fired, single boiler, stoker grate, utility electric generating station in the world) is used to demonstrate the theoretical principles. It has been observed that NO x emissions firing 100% whole tree chips with moisture contents as low as 40% by weight can be as low as 0.13 lb/MMBtu (MMBtu = 10 6 Btu) while still achieving a boiler efficiency in the range of 68% to 73% (in the high end of the design range) without the use of post-combustion treatment or flue gas recirculation (FGR). Problems of combustion and emissions control at steaming rates other than normal full-load are also examined. 2 figs., 4 tabs

  7. Heater for Combustible-Gas Tanks

    Science.gov (United States)

    Ingle, Walter B.

    1987-01-01

    Proposed heater for pressurizing hydrogen, oxygen, or another combustible liquid or gas sealed in immersion cup in pressurized tank. Firmly supported in finned cup, coiled rod transfers heat through liquid metal to gas tank. Heater assembly welded or bolted to tank flange.

  8. Homogeneous charge combustion of aqueous ethanol

    Science.gov (United States)

    2001-02-01

    The goal of this research is to reduce nitrous oxide (NOx) and carbon monoxide (CO) emissions and to retain the performance characteristics of a diesel engine by modifying the in-cylinder combustion process. To accomplish this goal, a direct-injected...

  9. Combustion of metals, prevention and fire fighting

    International Nuclear Information System (INIS)

    Mellottee, H.

    1991-01-01

    The paper reviews the knowledge on metal combustion. Few works are devoted on metals such as magnesium or titanium. On the contrary liquid metals used as coolants, especially sodium, are much more studied. Results obtained on pool fires and spray fires are briefly given for global safety analysis of LMFBR. 11 refs

  10. TOPICAL REVIEW: Plasma assisted ignition and combustion

    Science.gov (United States)

    Starikovskaia, S. M.

    2006-08-01

    In recent decades particular interest in applications of nonequilibrium plasma for the problems of plasma-assisted ignition and plasma-assisted combustion has been observed. A great amount of experimental data has been accumulated during this period which provided the grounds for using low temperature plasma of nonequilibrium gas discharges for a number of applications at conditions of high speed flows and also at conditions similar to automotive engines. The paper is aimed at reviewing the data obtained and discusses their treatment. Basic possibilities of low temperature plasma to ignite gas mixtures are evaluated and historical references highlighting pioneering works in the area are presented. The first part of the review discusses plasmas applied to plasma-assisted ignition and combustion. The paper pays special attention to experimental and theoretical analysis of some plasma parameters, such as reduced electric field, electron density and energy branching for different gas discharges. Streamers, pulsed nanosecond discharges, dielectric barrier discharges, radio frequency discharges and atmospheric pressure glow discharges are considered. The second part depicts applications of discharges to reduce the ignition delay time of combustible mixtures, to ignite transonic and supersonic flows, to intensify ignition and to sustain combustion of lean mixtures. The results obtained by different authors are cited, and ways of numerical modelling are discussed. Finally, the paper draws some conclusions on the main achievements and prospects of future investigations in the field.

  11. 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.

  12. 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 ...

  13. Premixed combustion on ceramic foam burners

    NARCIS (Netherlands)

    Bouma, P.H.; Goey, de L.P.H.

    1999-01-01

    Combustion of a lean premixed methane–air mixture stabilized on a ceramic foam burner has been studied. The stabilization of the flame in the radiant mode has been simulated using a one-dimensional numerical model for a burner stabilized flat-flame, taking into account the heat transfer between the

  14. 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.

  15. 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

  16. 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 ...

  17. Steam-moderated oxy-fuel combustion

    Energy Technology Data Exchange (ETDEWEB)

    Seepana, Sivaji; Jayanti, Sreenivas [Department of Chemical Engineering, IIT Madras, Adyar, Chennai 600 036 (India)

    2010-10-15

    The objective of the present paper is to propose a new variant of the oxy-fuel combustion for carbondioxide (CO{sub 2}) sequestration in which steam is used to moderate the flame temperature. In this process, pure oxygen is mixed with steam and the resulting oxidant mixture is sent to the boiler for combustion with a fossil fuel. The advantage of this method is that flue gas recirculation is avoided and the volumetric flow rates through the boiler and auxiliary components is reduced by about 39% when compared to the conventional air-fired coal combustion power plant leading to a reduction in the size of the boiler. The flue gas, after condensation of steam, consists primarily of CO{sub 2} and can be sent directly for compression and sequestration. Flame structure analysis has been carried out using a 325-step reaction mechanism of methane-oxidant combustion to determine the concentration of oxygen required to ensure a stable flame. Thermodynamic exergy analysis has also been carried out on SMOC-operated CO{sub 2} sequestration power plant and air-fired power plant, which shows that though the gross efficiency increases the absolute power penalty of {proportional_to}8% for CO{sub 2} sequestration when compared to air-fired power plant. (author)

  18. 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.

  19. 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...

  20. Combustion characteristics of the mustard methyl esters

    International Nuclear Information System (INIS)

    Bannikov, M.G.; Vasilev, I.P.

    2011-01-01

    Mustard Methyl Esters (further bio diesel) and regular diesel fuel were tested in direct injection diesel engine. Analysis of experimental data was supported by an analysis of fuel injection and combustion characteristics. Engine fuelled with bio diesel had increased brake specific fuel consumption, reduced nitrogen oxides emission and smoke opacity, moderate increase in carbon monoxide emission with essentially unchanged unburned hydrocarbons emission. Increase in fuel consumption was attributed to lesser heating value of bio diesel and partially to decreased fuel conversion efficiency. Analysis of combustion characteristics revealed earlier start of injection and shorter ignition delay period of bio diesel. Resulting decrease in maximum rate of heat release and cylinder pressure was the most probable reason for reduced emission of nitrogen oxides. Analysis of combustion characteristics also showed that cetane index determined by ASTM Method D976 is not a proper measure of ignition quality of bio diesel. Conclusion was made on applicability of mustard oil as a source for commercial production of bio diesel in Pakistan. Potentialities of on improving combustion and emissions characteristics of diesel engine by reformulating bio diesel were discussed. (author)

  1. 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...

  2. 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.

  3. Exhaust gas afterburner for internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Haertel, G

    1977-05-12

    The invention pertains to an exhaust gas afterburner for internal combustion engines, with an auxiliary fuel device arranged upstream from the afterburner proper and controlled by the rotational speed of the engine, which is additionally controlled by an oxygen or carbon monoxide sensor. The catalytic part of the afterburner, together with a rotochamber, is a separate unit.

  4. IMPROVED COMBUSTION PROCESSES IN MEDICAL WASTES ...

    African Journals Online (AJOL)

    A small rig was designed for conducting tests on the incineration of rural clinical wastes in Botswana. Experimental results showed that if proper combustion conditions are applied to low technology rural clinical waste incinerators, the operating temperatures could increase from around 400 to above 850oC. It was ...

  5. 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.

  6. Stoichiometric calculations of combustion of Lakhra lignite

    International Nuclear Information System (INIS)

    Ali, I.; Ali, M.M.

    2002-01-01

    Lakhra coal field is largest productive coal field of Pakistan. About 1.5 millions tonne of this coal is, annually, mined and transported daily to various parts of the country in 500 trucks each of 10 tonnes of coal. The major consumers of this coal are brick kilns located in Sindh and Punjab. It is available at Rs. 500/- per tonne at mine head. A number of attempts were made for the production of power (electricity) by foreign companies. Feasibility studies were undertaken but no one set up power plant. It may be due to inferior quality of coal as it is lignitic in nature with high ash and sulfur contents. This coal is also, very sensitive to spontaneous combustion. Spontaneous combustion is the auto-ignition of coal at ambient conditions. Hence there are storage problems. In spite of these drawbacks, a 3(50) Mega Watt (3 units of each 50 mega watt power generation capacity) power plant, based on atmospheric fluidized bed combustion of coal technology (AFBC), was setup in early nineties. The performance of this plant remained poor. The main reasons might be poor quality of coal and limestone. Limestone is used with high sulfur Lakhra lignite, in fluidized bed combustor, to arrest sulfur of the coal, fixing sulfur as calcium sulfate to minimize hazardous emissions of sulfur dioxide (SO/sub 2/). Spontaneous combustion of Lakhra lignite is responsible for each fire of coal and conveyor belt etc. (author)

  7. 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 ...

  8. 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.

  9. 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.

  10. 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...

  11. 40 CFR 74.16 - Application requirements for combustion sources.

    Science.gov (United States)

    2010-07-01

    ... combustion sources. 74.16 Section 74.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... for combustion sources. (a) Opt-in permit application. Each complete opt-in permit application for a combustion source shall contain the following elements in a format prescribed by the Administrator: (1...

  12. 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...

  13. 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...

  14. 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...

  15. 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. [Amdt. 25-72, 55 FR 29783, July 20, 1990...

  16. 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

  17. Multi-stage combustion using nitrogen-enriched air

    Science.gov (United States)

    Fischer, Larry E.; Anderson, Brian L.

    2004-09-14

    Multi-stage combustion technology combined with nitrogen-enriched air technology for controlling the combustion temperature and products to extend the maintenance and lifetime cycles of materials in contact with combustion products and to reduce pollutants while maintaining relatively high combustion and thermal cycle efficiencies. The first stage of combustion operates fuel rich where most of the heat of combustion is released by burning it with nitrogen-enriched air. Part of the energy in the combustion gases is used to perform work or to provide heat. The cooled combustion gases are reheated by additional stages of combustion until the last stage is at or near stoichiometric conditions. Additional energy is extracted from each stage to result in relatively high thermal cycle efficiency. The air is enriched with nitrogen using air separation technologies such as diffusion, permeable membrane, absorption, and cryogenics. The combustion method is applicable to many types of combustion equipment, including: boilers, burners, turbines, internal combustion engines, and many types of fuel including hydrogen and carbon-based fuels including methane and coal.

  18. 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. 1209.7 Section 1209.7 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY... for smoldering combustion. This section provides the test method for determining smoldering combustion...

  19. 24 CFR 3280.710 - Venting, ventilation and combustion air.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Venting, ventilation and combustion... Fuel Burning Systems § 3280.710 Venting, ventilation and combustion air. (a) The venting as required by... appliance listing and the appliance manufacturer's instructions. (b) Venting and combustion air systems...

  20. 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.