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Sample records for biomasa utilizando cfd

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

    Energy Technology Data Exchange (ETDEWEB)

    Rogel Ramirez, Alejandro

    2007-07-01

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

  2. CFD modelling of an open core downdraft moving bed biomass gasifier; Modelado de un gasificador estratificado de lecho movil de biomasa, utilizando CFD

    Energy Technology Data Exchange (ETDEWEB)

    Rogel-Ramirez, A [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)]. E-mail: ARogelR@iingen.unam.mx

    2008-10-15

    This paper contains the description of a bidimensional Computational Fluid Dynamics (CFD), model Developer to simulate the flow and reaction in a stratified downdraft biomass gasifier, whereby Eulerian conservation equations are solved for particle and gas phase components, velocities and specific enthalpies. The model is based on the PHOENICS package and represents a tool which can be used in gasifier analysis and design. Contributions of chemical kinetics and the mixing rate using the EBU approach are considered in the gas phase global homogeneous reactions. The harmonic blending of chemical kinetics and mass transfer effects, determine the global heterogeneous reactions between char and O{sub 2}, CO{sub 2} and H{sub 2}O. The turbulence effect in the gas phase is accounted by the standard {kappa}-{epsilon} approach. The model provides information of the producer gas composition, velocities and temperature at the outlet, and allows different operating parameters and feed properties to be changed. Finally, a comparison with experimental data available in literature was done, which showed satisfactory agreement from a qualitative point of view, though further validation is required. [Spanish] Este estudio describe un modelo numerico bidimensional, basado en Dinamica de Fluidos Computacional (CFD), desarrollado para simular el flujo y las reacciones que ocurren en un gasificador estratificado de flujos paralelos, en el que se resuelven ecuaciones de conservacion Eulerianas para los componentes de la fase gaseosa, la fase solida, velocidades y entalpias especificas. El modelo esta basado en el codigo PHOENICS y representa una herramienta que puede ser utilizada en el analisis y diseno de gasificadores. En las reacciones globales homogeneas se consideran las contribuciones de la cinetica quimica y la rapidez de mezclado, usando el modelo Eddy Brake-UP (EBU). La medida harmonica de la cinetica quimica y la transferencia de masa, determinan las velocidades globales de

  3. Producción de ácido láctico a partir de biomasa de origen vegetal

    OpenAIRE

    Fernández Díez, Laura

    2014-01-01

    Se va a estudiar la conversión a ácido láctico de distintos tipos de biomasa, siendo necesario que la biomasa presente fructosa en su composición. Las biomasas que se utilizarán serán: sacarosa, melaza de caña, melaza de remolacha e inulina. Para ello se empleará una planta piloto con unas condiciones de trabajo de 400 ºC y 25 MPa, con un tiempo de residencia de 3 segundos, utilizando un catalizador con grupos hidroxilo. Una vez efectuada la reacción, los productos se llevarán a una cámara fl...

  4. Flow prediction and heat transfer in a cooling square duch of a gas turbine blade using CFD; Predicciones de flujo y transferencia de calor en un conductor de alabe enfriado de turbina de gas utilizando CFD

    Energy Technology Data Exchange (ETDEWEB)

    Urquiza B, Gustavo [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Sierra E, Fernando [Universidad Nacional Autonoma de Mexico, Mexico D.F. (Mexico); Kubiak S, Janusz; Campos A, Rafael [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2003-10-15

    A numerical investigation has been conducted to study the turbulent flow and the heat transfer in a blade turbine coolant passage involving a 180 degrees turn. The study provides a comparison test for two turbulence models. The numerical solution was conducted employing two models for turbulence, the renormalization Group Theory (RNG) and the Reynolds Stress Model (RSM), using a refined grid to model with detail the recirculating flow. Computations are performed with a commercial finite volume code which solves three dimensional, incompressible, Navier-Stokes and Energy equations. At the passage turn, significant secondary flows are present, formed by a pair of symmetrical vortices. Results have been compared against published experimental data for Re = 53 000. Very good agreement is achieved for the prediction of the local static pressure distribution along the passage. A strong effect of rotation has been observed mainly in the flow field as described in detail in the paper. [Spanish] En este trabajo se presenta una investigacion numerica para estudiar el flujo turbulento y la transferencia de calor en un conducto de enfriamiento de un alabes de turbina de gas con giro de 180 grados. El estudio proporciona una comparacion de resultados para dos modelos de turbulencia. La solucion numerica emplea dos modelos de turbulencia: el modelo de esfuerzos de Reynolds (RSM) y el modelo de la teoria del grupo de renormalizacion (RNG), utilizando una malla refinada para modelar con detalle el flujo de recirculacion. Los calculos fueron realizados con un codigo comercial de volumenes finitos el cual resuelve las ecuaciones tridimensionales de Navier-Stoke y de energia para flujo incompresible. En la seccion de giro del conductor, aparecen flujos secundarios significativos, formados por un par de celulas simetricas. Los resultados han sido comparados contra datos experimentales de la literatura para Re = 53 000. se obtuvo un buen acuerdo para la prediccion de la distribucion de

  5. Piloto de gasificador downdraft operado con biomasa

    OpenAIRE

    Cuba Arroyo, Carlos Guillermo

    2011-01-01

    En este Proyecto Final de Carrera se lleva a cabo la ingeniería básica de un piloto de gasificación de biomasa, en el contexto de la producción de energía eléctrica, a partir de fuentes renovables de energía. Primeramente se realiza un estudio bibliográfico y la revisión del estado actual de la tecnología de los gasificadores para detectar a los posibles fabricantes de este sistema. A nivel comercial y en Catalunya se ha detectado a uno solo, que es la empresa Logic-energy S...

  6. Selección de una levadura para la producción de biomasa: crecimiento en suero de queso

    Directory of Open Access Journals (Sweden)

    Wendy Zumbado-Rivera

    2006-01-01

    Full Text Available El presente proyecto se realizó con el objetivo de recomendar una especie de levadura para la producción de biomasa, utilizando como sustrato el suero de leche del proceso de elaboración de queso blanco tipo Turrialba. Se compararon las especies Kluyveromyces marxianus, Candida kefyr y Saccharomyces cerevisiae por medio de su crecimiento en un sistema de fermentación por lotes. Se determinó el tiempo de fermentación, la productividad total y el contenido de proteína de la biomasa. Al comparar la variación en el tiempo según la levadura utilizada, se obtuvo diferencias significativas (p ≤ 0,05. Las levaduras K. marxianus y C. kefyr presentaron un tiempo de 19 y 18 horas, respectivamente y S. cerevisiae, un tiempo de 24 horas. Con respecto a la productividad total de biomasa, la especie K. marxianus presentó un valor de 0,22 g/lxh, resultando significativamente diferente (p ≤ 0,05 a las especies C. kefyr y S. cerevisiae, para las cuales se obtuvieron productividades de 0,14 y 0,13 g/lxh. La variación en el contenido de proteína de acuerdo con la levadura utilizada no resultó significativo (p ≥ 0,05. Para la especie K. marxianus se obtuvo un contenido de proteína de 32%, 34% para C. kefyr y 35% para S. cerevisiae. Se seleccionó la especie de levadura Kluyveromyces marxianus para la producción de proteína unicelular, por presentar un menor tiempo de fermentación, mayor productividad e igual contenido proteico de la biomasa que las otras levaduras, además de facilidades de utilización

  7. RELACIÓN BIOMASA DE RAÍZ/BIOMASA TOTAL DE SOJA (Glycine max EN DOS SISTEMAS DE LABRANZA

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    Mónica Beatriz Barrios

    2014-06-01

    Full Text Available La soja es el principal cultivo en Argentina debido a su adaptación a los suelos, la incorporación de tecnología con el empleo de la siembra directa y el precio del mercado internacional. Las propiedades físicas, químicas y biológicas de cada suelo se ven modificadas por el tipo de sistema de laboreo empleado. El entorno generado por la labranza altera el crecimiento y el equilibrio funcional de los cultivos herbáceos. En el año 2006, se instaló un ensayo en el Partido de Ezeiza (Pampa Ondulada, con el objetivo de evaluar los efectos del sistema de laboreo en el equilibrio funcional entre biomasa de raíces/biomasa total en soja (Glycine max durante la campaña 2012/2013. Se utilizó un diseño de bloques completos al azar con dos tratamientos que consistieron en: labranza convencional (LC y siembra directa (SD, con cuatro repeticiones. Se midió: peso de biomasa aérea, área foliar, rendimiento en grano, peso de raíces de 0-10 y 10-20 cm de profundidad, y se calculó biomasa total y la relación biomasa de raíces/biomasa total. El peso de raíces se determinó con el método del cilindro, el área foliar con el paquete estadístico Iproplus y el rendimiento con el cuadrado de corte. Los datos obtenidos fueron sometidos a análisis de varianza y las medias de los tratamientos fueron comparadas según Tukey (P < 0.05. El efecto del sistema de labranza generó diferentes respuestas en función de la variable evaluada y la fecha de muestreo. LC resultó significativamente superior (P < 0.05 respecto a SD en biomasa total y biomasa aérea en las etapas fenológicas R3 y R5; biomasa de raíces en R1 y R3; IAF en R2, R3 y R5. El rendimiento en grano fue mayor en LC respecto de SD, sin embargo el sistema de labranza no afectó la relación biomasa de raíz/biomasa total.

  8. Potencial generador de biomasa como fuente renovable a escala local

    OpenAIRE

    PERELLÓ GUARRO, PAULA ISABEL

    2013-01-01

    Gran parte de los residuos agrícolas y forestales pueden ser utilizados como biomasa. El aprovechamiento de estos recursos como fuente de energía renovable puede ser la solución a muchos de los problemas medioambientales y económicos que existen actualmente. El objeto del presente proyecto es realizar un inventario del potencial generador de biomasa como fuente renovable a escala local. El trabajo ha sido estructurado en dos grandes partes. La primera contiene, a modo de preliminares, aquello...

  9. ESTUDIO CINÉTICO DEL PROCESO DE DEVOLATILIZACIÓN DE BIOMASA LIGNOCELULÓSICA MEDIANTE ANÁLISIS TERMOGRAVIMÉTRICO PARA TAMAÑOS DE PARTÍCULA DE 2 A 19 mm

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    ANDRÉS MELGAR

    2008-01-01

    Full Text Available Con el objetivo de proporcionar herramientas que mejoren el diseño de los sistemas de gasificación/combustión de biomasa, y los modelos cinético-químicos de dichos procesos, se presenta un estudio de la cinética química asociada al proceso de devolatilización de biomasa mediante pruebas de termogravimetría utilizando tamaños de partícula que varían de 2 a 19 mm, y tasas de calentamiento de 10, 15 y 20 K/min. El desarrollo de este trabajo se justifica debido a que no hay resultados disponibles en la bibliografía que estudien tamaños superiores a 1 mm. Mediante el ajuste de los puntos experimentales utilizando un modelo de primer orden se determinan los parámetros de las constantes cinéticas (forma de Arrhenius. El estudio muestra que la energía de activación es directamente proporcional a la tasa de calentamiento y al tamaño de partícula, se comprueba que el proceso de descomposición térmica de la biomasa se da a temperaturas más altas con el aumento del tamaño de las partículas, debido a la importancia que toman los procesos de transferencia calor y masa. Los parámetros cinéticos calculados pueden ser utilizados en los modelos dimensionales del proceso de gasificación-combustión de biomasa, considerando el tamaño de las partículas intrínseco en la cinética.

  10. Aprovechamiento energético de la biomasa

    OpenAIRE

    Velo García, Enrique

    2006-01-01

    A diferencia de otras fuentes potenciales de energía como el sol, el viento o el agua, la biomasa (cualquier tipo de materia orgánica cuyo origen inmediato sea un proceso biológico, vegetal o animal) presenta una gran diversidad de vías o procesos a partir de los cuales se puede obtener energía. Si a esta diversidad le añadimos la gran variedad de la materia orgánica en cuanto a orígenes, composición y modos de recolección y tratamiento, nos encontramos con un amplio y variado esc...

  11. Proyecto de una central eléctrica de biomasa

    OpenAIRE

    Valentín Botija, Sergio

    2011-01-01

    El presente Proyecto de fin de carrera pretende dar una respuesta técnica a la necesidad de abastecimiento e independencia energética mediante una solución basada en las energías renovables y en combustibles vegetales, en concreto aquella basada en la biomasa; así como profundizar en el conocimiento de las mismas y realizar un estudio de viabilidad de estas técnicas en una zona determinada de Castilla-La Mancha. De modo, que mediante este PFC se trata de analizar la viabilidad técnica y econó...

  12. Valorización de derivados de biomasa: producción de levulinato de etilo con bajo impacto ambiental empleando un heteropoliácido de estuctura Preyssler

    OpenAIRE

    Pasquale, Gustavo Antonio; Ruiz, Diego Manuel; Sathicq, Ángel Gabriel; Baronetti, Graciela T.; Gustavo P. Romanelli

    2015-01-01

    El ácido levulínico (LA), derivado de la catálisis ácida de la biomasa lignocelulósica, uno de los pilares del top-twelve building blocks, es potencialmente una molécula versátil para la síntesis de sustancias químicas para aplicaciones como aditivos de combustibles, precursores de polímeros y resinas. Por ejemplo, el levulinato de etilo (EL), obtenido por esterificación del LA con etanol, puede utilizarse como un aditivo en combustibles.Por otro lado, los procesos catalíticos utilizando hete...

  13. Enriquecimiento de biomasa de levadura con micronutrientes esenciales

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    Miguel A. Otero

    2008-01-01

    Full Text Available Se estudian las potencialidades de enriquecimiento de la biomasa de levaduras GRAS a partir de medios de cultivo ricos en micronutrientes de interés, básicamente, cromo y selenio. La levadura tiene la propiedad de incorporar a su biomasa cantidades elevadas de componentes del medio aún cuando no se utilicen metabólicamente. Las dietas diarias actuales, incluso en los países desarrollados, son regularmente deficitarias en Se y Cr, elementos esenciales para el comportamiento metabólico estable. El Cr es un componente del Factor de Tolerancia a la Glucosa (GTF que facilita las funciones de la insulina. Por medio de las técnicas del batch incrementado se puede llegar a concentraciones de Cr y Se de hasta 1000 ppm. Los productos puede ser empleado en la prevención y profilaxis de la Diabetes mellitus, en su variante senil, en tanto que el Se juega un rol antioxidante primordial.

  14. BIOMASA EN PLANTACIONES DE Eucalyptus viminalis Labill. DE LA PROVINCIA DE BUENOS AIRES, ARGENTINA

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    Paula Ferrere

    2008-01-01

    Full Text Available El presente trabajo se desarrolló en el oeste de la provincia de Buenos Aires, Argentina con el objetivo de ajustar funciones de biomasa de árboles individuales y determinar la biomasa en diferentes compartimientos de la planta y el sotobosque. Se identificaron rodales de Eucalyptus viminalis Labill. cuyas edades oscilaron entre 4 y 14 años. Se apearon 21 árboles con diámetros entre 9,2 y 32,5 cm. Se desarrollaron regresiones simples y múltiples y se estimó el volumen, la biomasa en ramas, hojas y fuste. Las ecuaciones de volumen de mejor comportamiento son basadas en modelos lineales en su forma normal, y el modelo más adecuado fue el que incorporó al d2 (R2 = 0,92. Para la estimación de la biomasa en hojas, ramas, copa y fuste se recomienda los modelos ln-ln que consideran el d y h o solo el d. El componente de la biomasa en hojas presentó una estimación más débil. La distribución de la biomasa en los individuos sigue el patrón de desarrollo que se encuentra en la bibliografía. La proporción de la biomasa en la copa disminuye con la edad, contrariamente a lo sucedido con el fuste.

  15. Efectos de vinazas sobre bacterias rizosféricas y en la actividad-CO2 y biomasa-C microbiana de un suelo Pachic Haplustoll

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    Miriam Rosero G

    2013-04-01

    Full Text Available En condiciones de casa de malla de la Universidad Nacional de Colombia sede Palmira se estudió los efectos de la aplicación de vinaza, un subproducto de la industria de alcohol carburante, sobre las bacterias rizosféricas Pseudomonas fluorescens y Bacillus subtilis promotoras de crecimiento, la actividad-CO2, biomasa microbiana-C y el cociente metabólico-qCO2 en un suelo Pachic Haplustoll y su relación con el rendimiento de habichuela (Phaseolus vulgaris L.. Se utilizó un diseño completamente al azar con siete tratamientos y cinco repeticiones. Los tratamientos se seleccionaron con base en los requerimientos de K del cultivo (150 kg/ha K2O utilizando como fuentes KCl y vinaza solos y en mezclas. Los tratamientos evaluados y la época de muestreo influyeron (P < 0.05 en la actividad y biomasa microbiana. Los menores valores de estas variables se presentaron en la época de floración del cultivo cuando la demanda de nutrientes es alta. La mezcla en partes iguales de vinaza y KCl favorece la mayor producción de habichuela sin afectar la actividad microbiana; el cociente metabólico indicó estabilidad del sistema en el tiempo y las bacterias rizosféricas presentaron el mejor crecimiento en la mezcla 75% de potasio como vinaza y 25% como KCl.

  16. Existencias y tasas de incremento neto de la biomasa y del carbono en bosques primarios y secundarios de Colombia

    OpenAIRE

    Orrego Suaza, Sergio Alonso; Del Valle Arango, Jorge Ignacio

    2002-01-01

    En 33 parcelas permanentes de 1000 m2 (0,1 ha) en bosques primarios y 77 parcelas permanentes de 500 m (0,05 ha) en bosques secundarios, para un área de muestreo de 7,15 ha, se estimaron las existencias de biomasa y del carbono almacenado en los siguientes compartimientos: biomasa aérea, necromasa, biomasa subterránea y suelo. La biomasa aérea total viva en los bosques primarios promedió 246,542 t/ha, representada 92,42% por árboles y arbustos dicotiledóneos, 5,93% en palmas (3,58% la pa...

  17. CFD and Ventilation Research

    DEFF Research Database (Denmark)

    Li, Y.; Nielsen, Peter V.

    2011-01-01

    of scientific research and engineering development of complex air distribution and ventilation systems in buildings. This review discusses the major and specific challenges of CFD in terms of turbulence modelling, numerical approximation, and boundary conditions relevant to building ventilation. We emphasize...... the growing need for CFD verification and validation, suggest on-going needs for analytical and experimental methods to support the numerical solutions, and discuss the growing capacity of CFD in opening up new research areas. We suggest that CFD has not become a replacement for experiment and theoretical......There has been a rapid growth of scientific literature on the application of computational fluid dynamics (CFD) in the research of ventilation and indoor air science. With a 1000–10,000 times increase in computer hardware capability in the past 20 years, CFD has become an integral part...

  18. Calefaccion centralizada por biomasa, Cuéllar

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    Verdú Pérez, Jesús

    2001-10-01

    Full Text Available A plant of municipal central heating feeded with residual biomass, has been created in Cuéllar (Segovia, Spain, in order to demostrate its technical viability and to make more confortable the life of village inhabitants. Those residual biomass used as combustible, comes from the pine seeds, the key industry in the area. The calorific energy generated by combustion of those pine seeds, serves to heat the water to be send later through different pipes crossing the village. So, heating services and sanitary hot water are used according to the moment of the year. The study of the operative plant, allow us to discern the more adecuated operation parameters. reaching a total thermical yield of 60%. So its technical and economical viability concerning other traditional combustibles, its big environmental contribution to the production of energy, in addition to the social advantages -1ike the creation of new working jobs and the development of alternative activities in agricultura1 and forest areas- have contributed to present this plant as a model to be extended to other areas with potential biomass.Con el fin de demostrar su viabilidad técnica y económica y dar servicio a los habitantes de la localidad, se ha instalado en Cuéllar (Segovia, España, una planta de calefacción municipal alimentada con biomasa residual. Como combustible utiliza los residuos biomásicos procedentes de la industria piñonera de la zona. La energía calorífica generada por el proceso de combustión de éstos, calienta agua que es distribuida a través de un circuito de tuberías aisladas a través de la ciudad. Se proporcionan así los servicios de calefacción y agua caliente sanitaria según la época del año. El estudio de la operación de la planta, ha permitido caracterizar los parámetros de funcionamiento más adecuados. habiéndose obtenido un rendimiento térmico total de la instalación del 60%. quedando justificada su viabilidad técnica y econ

  19. LA BIOMASA DE LOS CULTIVOS EN EL AGROECOSISTEMA. SUS BENEFICIOS AGROECOLÓGICOS

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    Anirebis Martínez Romero

    2014-01-01

    Full Text Available La biomasa es el resultado de la transformación de la energía solar en energía química. El hombre a través de la historia la ha utilizado no solo para su alimentación sino también para la alimentación de sus animales. Los avances de la ciencia promovieron el desarrollo agrario basado en la revolución verde, la cual solo promueve la producción de alimentos ya sea de uso humano o animal, marginando la importancia de la biomasa como enriquecedor del recurso suelo al disponerse de los insumos necesarios para sustituir su fertilidad natural. En la actualidad la producción y conservación de la biomasa de cualquier cultivo cobra una importancia trascendente; porque ello contribuye, además, a la protección medioambiental a través de la captura de carbono. El presente trabajo tuvo como objetivo demostrar la importancia que proporciona la biomasa generalmente no alimenticia para los humanos, a fin de emplearla no solo como alimento animal, sino también como enriquecedora del recurso natural suelo. Las investigaciones realizadas en Cuba sobre el tema es pobre, aun cuando en la actualidad resulta de gran importancia encontrar variantes que permitan profundizar en la producción de biomasa en su relación con el medio ambiente. Finalmente se exponen los resultados preliminares sobre producción de biomasa a partir de la agrobiodiversidad presente en los escenarios productivos, a la vez que se reflexiona sobre la importancia del tema para futuras investigaciones.

  20. Estudio cinético de una fermentación alcohólica utilizando miel de abejas como sustrato

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    José Ángel Gómez

    2011-06-01

    Full Text Available El artículo describe un estudio cinético de una fermentación alcohólica utilizando miel de abejas como sustrato; para este efecto se realizaron nueve fermentaciones en proceso discontinuo con un volumen, de 10 L, siguiendo el comportamiento de las concentraciones de sustrato, biomasa y producto en el tiempo. Se evaluó la conveniencia de factores como la agitación y la adición de nutrientes, además, se observa el efecto de las concentraciones iniciales de sustrato e inocula y el tipo de miel.

  1. Productividad y biomasa fitoperifítica en los Lagos Tarapoto y Yahuarcaca, Amazonas, Colombia Productividad y biomasa fitoperifítica en los lagos Yahuarcaca y Tarapoto (Amazonas - Colombia

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    Duque Escobar Santiago R.

    2000-06-01

    Full Text Available In the littoral zone, near of the matrix the macrophytes, main for Paspalum spp the lake Yahuarcaca and Tarapoto; the floodplain of the Amazon River-Colombia, through were designed system of artificial substratum, using slips and rods we quantify the productivity primary phytoperiphyton for clorophyl a, through method espectrophotometric and the biomass for ash free dry weight; in three periods hidrology low water, filling water and high water; for two, four and eigh day the colonization; four deep levels and radial position the substratum. The factors that has mayor effect over the primary productivity and the biomass phytoperiphytic are the hidrobiology periods, the colonization of the substratum and deep. The productivity and biomass from the lake is reationship with the mineralization of the water, with the tramsportation of nutrients of afluents, macrophytes, the flood forest, decomposition and the recirculation of nutrients in the water column.En la zona litorial, cerca de la matriz de macrófitas conformadas principalmente por Paspalum spp de los lagos Yahuarcaca y Tarapoto, del plano de inundación del Río Amazonas-Colombia, mediante el diseño de un sistema de substratos artificiales, utilizando láminas portaobjetos y tubos de vidrio, se cuantificó la productividad primaria fitoperifítica por clorofila a, mediante el método espectrofotométrico y la biomasa por peso seco libre de cenizas (PSLC, en tres períodos hidrológicos, aguas bajas, ascenso y altas o desborde; a los 2, 4 y 8 días de colonización; cuatro niveles de profundidad (cada 10

  2. Enfermedad pulmonar obstructiva crónica por exposición al humo de biomasa

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    Matías Lopez

    2014-03-01

    Full Text Available En este artículo se discute la relación existente entre la enfermedad pulmonar obstructiva crónica (EPOC y el humo de biomasa. Más de la mitad de la población utiliza biomasa como combustible principal, sobre todo en áreas rurales y en países en vías de desarrollo donde su uso llega hasta el 80%. La inhalación del humo de biomasa crea un estado inflamatorio crónico, que se acompaña de una activación de metaloproteinasas y una reducción de la movilidad mucociliar. Esto podría explicar la gran asociación existente entre la exposición a biomasa y EPOC, revelada por estudios observacionales y epidemiológicos provenientes de países en vías de desarrollo y de países desarrollados. En esta revisión exploramos también las diferencias entre la EPOC causada por tabaco y por biomasa, y encontramos que, a pesar de las diferencias fisiopatológicas, la mayoría de las características clínicas, calidad de vida y mortalidad fueron parecidas. En los últimos diez años se han realizado intervenciones para disminuir la exposición a biomasa mediante el uso de cocinas mejoradas y combustibles limpios, sin embargo, estas estrategias todavía no han sido exitosas debido a su incapacidad para reducir los niveles de contaminación a niveles recomendados por la Organización Mundial de la Salud, y por su falta de uso. Por lo tanto, hay una necesidad urgente de ensayos de campo aleatorios, cuidadosamente realizados, para determinar la verdadera gama de reducciones de contaminación potencialmente alcanzables, la probabilidad de su uso y los beneficios a largo plazo en la reducción de la gran carga mundial de EPOC

  3. MOŽE LI BIOMASA POKRENUTI ENERGIJSKU TRANZICIJU U HRVATSKOJ I JUGOISTOČNOJ EUROPI?

    OpenAIRE

    Domac, Julije; Risović, Stjepan; Šegon, Velimir; Pentek, Tibor; Šafran, Branimir; Papa, Ivica

    2015-01-01

    Šumska biomasa predstavlja važan izvor energije, čijem bi se korištenju u budućnosti trebalo posvetiti znatno više pozornosti. Biomasa u svojim tradicionalnim oblicima je i dalje vrlo važan izvor energije u većini zemalje Jugoistočne Europe, te će u doglednoj budućnosti i dalje biti tako. Međutim, sve se više koristi ne samo za proizvodnju toplinske energije, već za proizvodnju električne i rashladne energije, i to se smatra kao važan dio energijske tranzicije koja je obećavajući model ...

  4. Modelos matemáticos y experimentales sobre el secado de biomasa

    Directory of Open Access Journals (Sweden)

    Jorge Armando Villalba Vidales

    2015-01-01

    Full Text Available El secado de biomasa como proceso previo a la combustión se ha convertido en la actualidad en un factor decisivo para mejorar la eficiencia de dichos procesos en los sectores industrial y residencial. Debido a la creciente importancia de este proceso, los investigadores han desarrollado una gran cantidad de modelos, tanto teóricos como experimentales, que buscan predecir la cinética de secado de diferentes tipos de biomasa. Si bien se han logrado grandes avances en el desarrollo de modelos, aún no existe un modelo unificado que permita predecir los perfiles de temperatura y humedad para diversos materiales. Dichas dificultades se generan fundamentalmente por la amplia diversidad de biomateriales y las grandes diferencias entre los procesos existentes. El propósito de este artículo es brindar una panorámica sobre el estado del arte relativo a modelos, tanto matemáticos como experimentales, utilizados en la actualidad para simular procesos de secado de la biomasa. Asimismo, proponer los elementos fundamentales que deberá poseer un modelo de secado unificado.

  5. Dicty_cDB: CFD579 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD579 (Link to dictyBase) - - - Contig-U16381-1 CFD579P (Link to Original site) CFD...579F 129 CFD579Z 319 CFD579P 448 - - Show CFD579 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-D/CFD579Q.Seq.d/ Representative seq. ID CFD...579P (Link to Original site) Representative DNA sequence >CFD579 (CFD579Q) /CSM/CF/CFD5-D/CFD5...alignments: (bits) Value CFD579 (CFD579Q) /CSM/CF/CFD5-D/CFD579Q.Seq.d/ 220 1e-56 CFD769 (CFD769Q) /CSM/CF/CFD7-C/CFD

  6. Dicty_cDB: CFD557 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD557 (Link to dictyBase) - - - Contig-U16450-1 CFD557E (Link to Original site) CFD...557F 601 CFD557Z 707 CFD557P 1308 CFD557E 1253 Show CFD557 Library CF (Link to library) Clone ID CFD...ginal site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-C/CFD557Q.Seq.d/ Representative seq. ID CFD...557E (Link to Original site) Representative DNA sequence >CFD557 (CFD557Q) /CSM/CF/CFD5-C/CFD...ragtvsfyl spkmtsdapadpsqdvffqnsihsspfgnctkyyentnnatctacfdlpmdispglyilq ffwefnpkgi

  7. Estudio: cantidad y costes de aprovechamiento de la biomasa existente en el T.M. de Carcaixent y el estudio de viabilidad para la ejecución de una Planta de Biomasa

    OpenAIRE

    MARTÍNEZ ABARCA, MARÍA BELINDA

    2013-01-01

    El objetivo general que se plantea en el presente trabajo es la evaluación de la disponibilidad de recursos y determinar la cantidad de la biomasa extraíble procedentes de las plantaciones de naranjos y otros cultivos existentes en el Término Municipal de Carcaixent. Se pretende estudiar la viabilidad económica de la extracción de biomasa de zonas forestales, agrícolas y zonas verdes del municipio mediante tratamientos selvícolas adecuados. El aprovechamiento de estos res...

  8. Efecto de nutrientes sobre la producción de biomasa del hongo medicinal Ganoderma lucidum

    Directory of Open Access Journals (Sweden)

    Ana María Torres López

    2011-04-01

    Full Text Available  Effect of nutrients in the biomass production of the medicinal mushroom Ganoderma lucidum Título corto: Efecto de nutrientes sobre la producción de G. lucidumResumen El hongo Ganoderma lucidum, en los constituyentes de su biomasa, tiene compuestos con propiedades benéficas para la salud; es por esto que el conocimiento de las condiciones nutricionales adecuadas para su crecimiento permitirá su producción industrial y a bajo costo. En este trabajo se evaluó a nivel de matraz el efecto de la relación C/N, y la presencia de diferentes fuentes de carbono, nitrógeno y micronutrientes sobre la producción de biomasa. Empleando glucosa y peptona como fuentes de carbono y nitrógeno, respectivamente, se encontró una relación C/N óptima de 16,7:1 para la cual la máxima producción de biomasa fue de 25 g/L. Manteniendo esta relación C/N, y sustituyendo la glucosa por lactosa o harina de cebada y la peptona por extracto de levadura, la producción de biomasa se incrementó a 35 g/L. En presencia de harina de cebada la adición al medio de cultivo de sales de Mg y K, y de tiamina, no generó un mayor incremento en la producción de biomasa. La producción de biomasa de G. lucidum se ve favorecida por la presencia en el medio de cultivo de relaciones C/N cercanas a las reportadas conforme a la composición típica de los hongos, así como por la presencia de sustratos complejos como la harina de cebada que le aportan además de la fuente de carbono micronutrientes necesarios para su desarrollo. Palabras clave: harina de cebada, relación C/N, micronutrientes, fuentes de carbono, fuentes de nitrógeno.  AbstractGanoderma lucidum fungus has some biomass components with beneficial health properties. The knowledge about its nutritionals requirements for growing will favor its industrial production at lower cost. In this work, the effect of C/N ratio, the presence of different carbon, nitrogen and micronutrients sources, on fungal biomass

  9. Método basado en teledetección para estimar la emisión de gases efecto invernadero por quema de biomasa A remote sensing method to estimate greenhouse gas emissions from biomass burning

    Directory of Open Access Journals (Sweden)

    Jesús Adolfo Anaya Acevedo

    2011-01-01

    Full Text Available La quema de biomasa es una fuente importante de gases efecto invernadero en países en vías de desarrollo. En Colombia, el cambio de uso del suelo, la silvicultura y el sector agropecuario superan el 50% de las emisiones totales de efecto invernadero. El fuego se utiliza con frecuencia como un mecanismo para cambiar el uso del suelo. Los Llanos orientales y la Amazonía colombiana están sometidos todos los años a la quema de biomasa, especialmente entre enero y marzo. Los estudios en la distribución espacial y temporal de las emisiones son importantes de cara a los informes en el ámbito nacional. Este artículo de revisión describe el método para hacer estas estimaciones utilizando teledetección y algunos de los resultados disponibles para Colombia.Biomass burning is a major source of greenhouse gas emissions in developing countries. In Colombia, land use change, forestry and agriculture are responsible for more than 50% of the total greenhouse gas emissions. Fire is commonly used as a mechanism for land use change. In Colombia the Llanos Orientales and the Amazonia are subject to biomass burning every year during the dry season, especially from January to March. Studies of the spatial and temporal distribution of emissions are required for emissions report at a national level. The goal of this state of the art article is to describe a method to estimate emissions with a remote sensing approach and to present some of the variables already measured in Colombia.

  10. La biomasa en la producción de electricidad en España

    Directory of Open Access Journals (Sweden)

    Espejo Marín, Cayetano

    2005-06-01

    Full Text Available The generation of electricity using biomass began in Spain in the mid-1990s. In this paper, we examine the combustible products used in the generation of this type of electricity, the legal framework protecting its production, the evolution of the installed power and its territorial distribution, the environmental impact of biomass as a renewable energy, the energy policy supporting this technology and the problems for the development of biomass as a energy source in Spain.

    [es] La producción de electricidad con biomasa comienza su desarrollo en España a mediados de los años noventa. En este artículo se analizan los productos combustibles de biomasa destinados a la generación de electricidad, el marco legal que protege esta producción, la evolución de la potencia instalada y su distribución territorial, el impacto ambiental de la biomasa como energía renovable, la política energética de apoyo a esta tecnología, y los problemas para el desarrollo de la biomasa como fuente energética en España. [fr] La biomasse dans la production d´électricité en Espagne. La production d'électricité avec biomasse commence son développement en Espagne vers le milieu des années quatre-vingt-dix. Dans cet article nous analysons les produits combustibles de biomasse destines à engendrer de l'électricité, le cadre légal qui protégé cette production, l'évolution de la puissance installée, la répercussion de l'environnement de la biomasse comme énergie renouvelable, la politique énergétique de soutien à cette technologie et les problèmes pour le développement de la biomasse comme source énergétique en Espagne.

  11. Avances en el modelado de la combustión de biomasa en spouted bed cónico

    OpenAIRE

    Saldarriaga Elorza, Juan Fernando

    2015-01-01

    290 p. En aras del desarrollo de un modelo riguroso para la combustión de biomasa vegetal en lecho en surtidor, en este Trabajo se ha avanzado en cuatro pilares fundamentales cuya implementación en el futuro permitirá desarrollar una herramienta que simule el comportamiento en la cámara de combustión de distintas formas de biomasa vegetal. Esta herramienta facilitará la labor de diseño de futuras plantas y permitirá evaluar y adaptar el funcionamiento de las mismas a cada alimentación, lo ...

  12. Factores de expansión de biomasa en comunidades forestales templadas del norte de Durango, México

    OpenAIRE

    Flor María Silva-Arredondo; José de Jesús Návar-Cháidez

    2010-01-01

    La biomasa forestal, por lo general, es cuantificada en kilogramos por árbol o en toneladas por hectárea de peso verde o de peso seco. En un bosque es un elemento ambiental clave para calcular los montos de carbono que puedan liberarse a la atmósfera o bien fijarse, cuando estos ecosistemas son manejados para mitigar los gases de efecto invernadero. El presente trabajo se llevó a cabo en el norte del estado de Durango, México, con el objetivo de estimar la biomasa arbórea aérea (M) y los fact...

  13. CFD methods for wind turbines

    Science.gov (United States)

    Suatean, Bogdan; Colidiuc, Alexandra; Galetuse, Slelian

    2012-11-01

    The purpose of this paper is to present different CFD models used to determine the aerodynamic performance of horizontal axis wind turbine (HAWT). The models presented have various levels of complexity to calculate the aerodynamic performances of HAWT, starting with a simple model, the actuator line method, and ending with a CFD approach.

  14. Dicty_cDB: CFD434 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD434 (Link to dictyBase) - - - Contig-U14176-1 CFD434E (Link to Original site) CFD...434F 639 CFD434Z 499 CFD434P 1138 CFD434E 968 Show CFD434 Library CF (Link to library) Clone ID CFD...inal site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-B/CFD434Q.Seq.d/ Representative seq. ID CFD...434E (Link to Original site) Representative DNA sequence >CFD434 (CFD434Q) /CSM/CF/CFD4-B/CFD...0.0 CFK424 (CFK424Q) /CSM/CF/CFK4-A/CFK424Q.Seq.d/ 1003 0.0 CFD434 (CFD434Q) /CSM/CF/CFD4-B/CFD

  15. Hidrodinámica y Combustión de Biomasa Vegetal Residual en Spouted Bed Cónico

    OpenAIRE

    Achutegui Narbona, Aitor

    2014-01-01

    En este trabajo se ha analizado la fluidodinámica de diferentes biomasas en spouted bed ademas de la combustión de algunas de ellas. La fluidodínamica también se ha efectuado con diferentes dispositivos internos

  16. OBTENCIÓN DE UNA BEBIDA FERMENTADA A PARTIR DE SUERO DE QUESO UTILIZANDO CÉLULAS INMOVILIZADAS DE KLUYVEROMYCES MARXIANUS

    OpenAIRE

    Rocío Cóndor G.; Víctor Meza C.; Fanny Ludeña U.

    2014-01-01

    El presente estudio tuvo como objetivo principal optimizar la tecnología de producción de una bebida fermentada de suero de queso, utilizando Kluyveromyces marxianus e inmovilización de células. En el biorreactor de lecho empacado, se obtuvo el mayor rendimiento (11,46±0,81 oGL) con un flujo de 140-150 mL. h-1, una biomasa inmovilizada de 10% (v/v), una relación de columna de 1:12 (diámetro: longitud), tamaño de perlas de 3 mm de diámetro, adición de metabisulfito de sodio (100 pg. mL-1) y c...

  17. ESTIMACIÓN DE LA BIOMASA FORESTAL PARA LAS ESPECIES QUERCUS ROTUNDIFOLIA Y QUERCUS SUBER BASADA EN IMÁGENES DEL SATÉLITE QUICKBIRD

    OpenAIRE

    Sousa, Adélia; Marques da Silva, José; Gonçalves, Ana Cristina; Mesquita, Paulo; Silva, Luis; Baptista, F.J.

    2013-01-01

    para una buena gestión. Actualmente las técnicas de inventario y monitoreo de biomasa forestal son usualmente lentas, muy trabajosas y de elevado coste, verificándose así la necesidad de desarrollar otras técnicas, que sean fiables y con costes relativamente reducidos. El objetivo de este estudio es desarrollar una metodología para estimar la biomasa forestal de las especies Quercus rotundifolia y Quercus suber basada en imágenes del satélite QuickBird. La estimación de la biomasa...

  18. Produccion de Biomasa de Scenedesmus Obliquus en diferentes medios de cultivo.

    Directory of Open Access Journals (Sweden)

    V. Martínez

    2005-01-01

    Full Text Available Los nutrientes son factores fundamentales que afectan el rendimiento de los cultivos de microalgas, de ahí la importancia de llevar a cabo estudios a escala de laboratorio con cepas de interés científico y comercial. El objetivo del trabajo fue investigar la producción de biomasa de Scenedesmus obliquus en diferentes medios de cultivo. Se utilizaron dos reactores tipo columnas de 2 L de capacidad empleando medio Extracto de Suelo, y medio Albañal Sintético respectivamente, a los cuales se les adicionó el inóculo del cultivo (1%, en la fase logarítmica de crecimiento. Para mantener agitado y homogéneo el sistema, se suministró aire a razón de 100 L/h, que fue medido con un regulador de flujo y se colocaron en un local cuya temperatura media era de 29,7 o C. Los reactores trabajaron en modo discontinuo (batch. Se mantuvieron con un régimen de luz/oscuridad de 8/16 horas durante 18 días. Para seguir el comportamiento del cultivo se determinó la Densidad óptica, la clorofila a, los sólidos suspendidos volátiles, se midió el pH y la producción de biomasa en el sistema. La velocidad de crecimiento específico fue ¿ = 0,16 d-1 para el cultivo en el medio Agar extracto de suelo y ¿ = 0,33 d-1 para el cultivo en medio Albañal sintético. El tiempo de duplicación fue de 4,33 d'-1 para el cultivo en medio AES y 2,10 d-1 para el medio de Albañal Sintético. Se alcanzaron los valores más altos en la producción de biomasa en el medio Albañal, lo que demostró un mejor desarrollo de la microalga investigada en este medio.

  19. Dicty_cDB: CFD333 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD333 (Link to dictyBase) - - - Contig-U16560-1 CFD333P (Link to Original site) CFD...333F 126 CFD333Z 727 CFD333P 853 - - Show CFD333 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-B/CFD333Q.Seq.d/ Representative seq. ID CFD...333P (Link to Original site) Representative DNA sequence >CFD333 (CFD333Q) /CSM/CF/CFD3-B/CFD3...kiqd k*rl Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD333 (CFD333Q) /CSM/CF/CFD3-B/CFD

  20. Dicty_cDB: CFD143 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD143 (Link to dictyBase) - - - Contig-U12897-1 CFD143P (Link to Original site) CFD...143F 637 CFD143Z 415 CFD143P 1052 - - Show CFD143 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD1-B/CFD143Q.Seq.d/ Representative seq. ID CFD...143P (Link to Original site) Representative DNA sequence >CFD143 (CFD143Q) /CSM/CF/CFD1-B/CFD...equences producing significant alignments: (bits) Value CFD143 (CFD143Q) /CSM/CF/CFD1-B/CFD143Q.Seq.d/ 1491

  1. Dicty_cDB: CFD372 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD372 (Link to dictyBase) - - - Contig-U16560-1 CFD372P (Link to Original site) CFD...372F 119 CFD372Z 734 CFD372P 853 - - Show CFD372 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-C/CFD372Q.Seq.d/ Representative seq. ID CFD...372P (Link to Original site) Representative DNA sequence >CFD372 (CFD372Q) /CSM/CF/CFD3-C/CFD3...ki qdkegip Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD372 (CFD372Q) /CSM/CF/CFD3-C/CFD

  2. Dicty_cDB: CFD389 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD389 (Link to dictyBase) - - - Contig-U13875-1 CFD389P (Link to Original site) CFD...389F 614 CFD389Z 228 CFD389P 842 - - Show CFD389 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-D/CFD389Q.Seq.d/ Representative seq. ID CFD...389P (Link to Original site) Representative DNA sequence >CFD389 (CFD389Q) /CSM/CF/CFD3-D/CFD3...-cDNA Score E Sequences producing significant alignments: (bits) Value CFD389 (CFD389Q) /CSM/CF/CFD3-D/CFD38

  3. Dicty_cDB: CFD207 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD207 (Link to dictyBase) - - - Contig-U16560-1 CFD207P (Link to Original site) CFD...207F 120 CFD207Z 579 CFD207P 699 - - Show CFD207 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-A/CFD207Q.Seq.d/ Representative seq. ID CFD...207P (Link to Original site) Representative DNA sequence >CFD207 (CFD207Q) /CSM/CF/CFD2-A/CFD2...t alignments: (bits) Value CFD207 (CFD207Q) /CSM/CF/CFD2-A/CFD207Q.Seq.d/ 1088 0.0 CHD396 (CHD396Q) /CSM/CH/

  4. Dicty_cDB: CFD536 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD536 (Link to dictyBase) - - - Contig-U16361-1 CFD536P (Link to Original site) CFD...536F 552 CFD536Z 517 CFD536P 1069 - - Show CFD536 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-B/CFD536Q.Seq.d/ Representative seq. ID CFD...536P (Link to Original site) Representative DNA sequence >CFD536 (CFD536Q) /CSM/CF/CFD5-B/CFD...xsyhahniv Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD536 (CFD536Q) /CSM/CF/CFD5-B/CFD

  5. Dicty_cDB: CFD408 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD408 (Link to dictyBase) - - - Contig-U16243-1 CFD408P (Link to Original site) CFD...408F 596 CFD408Z 618 CFD408P 1214 - - Show CFD408 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-A/CFD408Q.Seq.d/ Representative seq. ID CFD...408P (Link to Original site) Representative DNA sequence >CFD408 (CFD408Q) /CSM/CF/CFD4-A/CFD...significant alignments: (bits) Value CFD408 (CFD408Q) /CSM/CF/CFD4-A/CFD408Q.Seq.

  6. Dicty_cDB: CFD208 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD208 (Link to dictyBase) - - - Contig-U15889-1 CFD208P (Link to Original site) CFD...208F 620 CFD208Z 562 CFD208P 1182 - - Show CFD208 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-A/CFD208Q.Seq.d/ Representative seq. ID CFD...208P (Link to Original site) Representative DNA sequence >CFD208 (CFD208Q) /CSM/CF/CFD2-A/CFD...DNA Score E Sequences producing significant alignments: (bits) Value CFD208 (CFD208Q) /CSM/CF/CFD2-A/CFD208Q

  7. Dicty_cDB: CFD247 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD247 (Link to dictyBase) - - - Contig-U16273-1 CFD247P (Link to Original site) CFD...247F 623 CFD247Z 396 CFD247P 1019 - - Show CFD247 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-B/CFD247Q.Seq.d/ Representative seq. ID CFD...247P (Link to Original site) Representative DNA sequence >CFD247 (CFD247Q) /CSM/CF/CFD2-B/CFD... Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD247 (CFD247Q) /CSM/CF/CFD2-B/CFD

  8. Dicty_cDB: CFD446 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD446 (Link to dictyBase) - - - Contig-U16560-1 CFD446P (Link to Original site) CFD...446F 119 CFD446Z 725 CFD446P 844 - - Show CFD446 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-B/CFD446Q.Seq.d/ Representative seq. ID CFD...446P (Link to Original site) Representative DNA sequence >CFD446 (CFD446Q) /CSM/CF/CFD4-B/CFD4...s CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD446 (CFD446Q) /CSM/CF/CFD4-B/CFD

  9. Dicty_cDB: CFD483 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD483 (Link to dictyBase) - - - Contig-U16339-1 CFD483P (Link to Original site) CFD...483F 622 CFD483Z 379 CFD483P 1001 - - Show CFD483 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-D/CFD483Q.Seq.d/ Representative seq. ID CFD...483P (Link to Original site) Representative DNA sequence >CFD483 (CFD483Q) /CSM/CF/CFD4-D/CFD...ducing significant alignments: (bits) Value CFD483 (CFD483Q) /CSM/CF/CFD4-D/CFD483Q.Seq.d/ 1717 0.0 SFJ650 (

  10. Dicty_cDB: CFD270 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD270 (Link to dictyBase) - - - Contig-U16560-1 CFD270P (Link to Original site) CFD...270F 119 CFD270Z 712 CFD270P 831 - - Show CFD270 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-C/CFD270Q.Seq.d/ Representative seq. ID CFD...270P (Link to Original site) Representative DNA sequence >CFD270 (CFD270Q) /CSM/CF/CFD2-C/CFD2...cing significant alignments: (bits) Value CFD270 (CFD270Q) /CSM/CF/CFD2-C/CFD270Q.Seq.d/ 1328 0.0 AFB143 (AF

  11. Dicty_cDB: CFD349 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD349 (Link to dictyBase) - - - Contig-U15323-1 CFD349P (Link to Original site) CFD...349F 461 CFD349Z 643 CFD349P 1104 - - Show CFD349 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-C/CFD349Q.Seq.d/ Representative seq. ID CFD...349P (Link to Original site) Representative DNA sequence >CFD349 (CFD349Q) /CSM/CF/CFD3-C/CFD...-cDNA Score E Sequences producing significant alignments: (bits) Value CFD349 (CFD349Q) /CSM/CF/CFD3-C/CFD

  12. Dicty_cDB: CFD223 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD223 (Link to dictyBase) - - - Contig-U16452-1 CFD223P (Link to Original site) CFD...223F 595 CFD223Z 416 CFD223P 1011 - - Show CFD223 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-A/CFD223Q.Seq.d/ Representative seq. ID CFD...223P (Link to Original site) Representative DNA sequence >CFD223 (CFD223Q) /CSM/CF/CFD2-A/CFD...DNA Score E Sequences producing significant alignments: (bits) Value CFD223 (CFD223Q) /CSM/CF/CFD2-A/CFD223Q

  13. Dicty_cDB: CFD216 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD216 (Link to dictyBase) - - - Contig-U16368-1 CFD216P (Link to Original site) CFD...216F 604 CFD216Z 406 CFD216P 1010 - - Show CFD216 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-A/CFD216Q.Seq.d/ Representative seq. ID CFD...216P (Link to Original site) Representative DNA sequence >CFD216 (CFD216Q) /CSM/CF/CFD2-A/CFD...Score E Sequences producing significant alignments: (bits) Value CFD216 (CFD216Q) /CSM/CF/CFD2-A/CFD216Q.Seq

  14. Dicty_cDB: CFD244 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD244 (Link to dictyBase) - - - Contig-U16511-1 CFD244P (Link to Original site) CFD...244F 686 CFD244Z 674 CFD244P 1360 - - Show CFD244 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-B/CFD244Q.Seq.d/ Representative seq. ID CFD...244P (Link to Original site) Representative DNA sequence >CFD244 (CFD244Q) /CSM/CF/CFD2-B/CFD...FG6-D/SFG691Q.Seq.d/ 759 0.0 CFD244 (CFD244Q) /CSM/CF/CFD2-B/CFD244Q.Seq.d/ 759 0

  15. Dicty_cDB: CFD741 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD741 (Link to dictyBase) - - - Contig-U11551-1 CFD741P (Link to Original site) CFD...741F 646 CFD741Z 330 CFD741P 976 - - Show CFD741 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD7-B/CFD741Q.Seq.d/ Representative seq. ID CFD...741P (Link to Original site) Representative DNA sequence >CFD741 (CFD741Q) /CSM/CF/CFD7-B/CFD7...re E Sequences producing significant alignments: (bits) Value CFD741 (CFD741Q) /CSM/CF/CFD7-B/CFD

  16. Dicty_cDB: CFD229 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD229 (Link to dictyBase) - - - Contig-U16287-1 CFD229P (Link to Original site) CFD...229F 583 CFD229Z 668 CFD229P 1251 - - Show CFD229 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-B/CFD229Q.Seq.d/ Representative seq. ID CFD...229P (Link to Original site) Representative DNA sequence >CFD229 (CFD229Q) /CSM/CF/CFD2-B/CFD...cing significant alignments: (bits) Value CFD229 (CFD229Q) /CSM/CF/CFD2-B/CFD229Q.Seq.d/ 2381 0.0 SLB722 (SL

  17. Dicty_cDB: CFD380 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD380 (Link to dictyBase) - - - Contig-U16381-1 CFD380P (Link to Original site) CFD...380F 124 CFD380Z 580 CFD380P 704 - - Show CFD380 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-D/CFD380Q.Seq.d/ Representative seq. ID CFD...380P (Link to Original site) Representative DNA sequence >CFD380 (CFD380Q) /CSM/CF/CFD3-D/CFD3...g significant alignments: (bits) Value CFD380 (CFD380Q) /CSM/CF/CFD3-D/CFD380Q.Seq.d/ 684 0.0 SLH820 (SLH820

  18. Dicty_cDB: CFD650 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD650 (Link to dictyBase) - - - Contig-U13873-1 CFD650P (Link to Original site) CFD...650F 516 CFD650Z 631 CFD650P 1147 - - Show CFD650 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-C/CFD650Q.Seq.d/ Representative seq. ID CFD...650P (Link to Original site) Representative DNA sequence >CFD650 (CFD650Q) /CSM/CF/CFD6-C/CFD...klkk Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD650 (CFD650Q) /CSM/CF/CFD6-C/CFD

  19. Dicty_cDB: CFD471 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD471 (Link to dictyBase) - - - Contig-U16241-1 CFD471P (Link to Original site) CFD...471F 641 CFD471Z 497 CFD471P 1138 - - Show CFD471 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-C/CFD471Q.Seq.d/ Representative seq. ID CFD...471P (Link to Original site) Representative DNA sequence >CFD471 (CFD471Q) /CSM/CF/CFD4-C/CFD...cDNA Score E Sequences producing significant alignments: (bits) Value CFD471 (CFD471Q) /CSM/CF/CFD4-C/CFD471

  20. Dicty_cDB: CFD826 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD826 (Link to dictyBase) - - - Contig-U14187-1 CFD826P (Link to Original site) CFD...826F 546 CFD826Z 289 CFD826P 835 - - Show CFD826 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-B/CFD826Q.Seq.d/ Representative seq. ID CFD...826P (Link to Original site) Representative DNA sequence >CFD826 (CFD826Q) /CSM/CF/CFD8-B/CFD8...quences producing significant alignments: (bits) Value CFD826 (CFD826Q) /CSM/CF/CFD8-B/CFD826Q.Seq.d/ 985 0.

  1. Respirómetro con biomasa fija sobre soporte permeable a gases.

    OpenAIRE

    Tejero Monzón, Juan Ignacio; Osa Olaizola, Juan José; Gómez Fuentes, Claudio

    1997-01-01

    Dispositivo para la realización de medidas respirométricas de líquidos que contengan materia orgánica, caracterizado por el empleo de membranas permeables a gases como soporte para la biomasa y como parte del sistema de oxigenación. La oxigenación se produce a través de la membrana directamente a la biopelícula adherida a la misma. La determinación de la tasa de respiración se realiza midiendo la cantidad de oxígeno que se transfiere a través de la membrana y corrigiendo el efecto del oxígeno...

  2. Perspectivas del potencial energético de la biomasa en el marco global y latinoamericano

    OpenAIRE

    Julián Rodrigo Quintero González; Laura Estefanía Quintero González

    2015-01-01

    El calentamiento global y los cambios climáticos que éste conlleva han fomentado desde hace algunos años la exploración de otros tipos de obtención energética para disminuir el uso del combustible fósil, siendo éste último uno de los principales causantes de dicho problema ambiental. El presente artículo expone algunas investigaciones recientes sobre la bioenergía u obtención de energía a partir de biomasa, considerada como energía limpia. Se abarcan temáticas como la bioenergía y sus posibil...

  3. Dicty_cDB: CFD543 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD543 (Link to dictyBase) - - - Contig-U16450-1 CFD543F (Link to Original site) CFD...543F 628 - - - - - - Show CFD543 Library CF (Link to library) Clone ID CFD543 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-B/CFD543Q.Seq.d/ Representative seq. ID CFD54...3F (Link to Original site) Representative DNA sequence >CFD543 (CFD543Q) /CSM/CF/CFD5-B/CFD543Q.Seq.d/ GTTTT...*ihktipn*igsimwpstkkkffnyqsl*fktsngkfpswskdlptwparnhatal ragtvsfylspkmtsdapadpsrdvffqnsihsspfgnctkyyentnnatctacfd

  4. Dicty_cDB: CFD460 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD460 (Link to dictyBase) - - - Contig-U16450-1 CFD460F (Link to Original site) CFD...460F 627 - - - - - - Show CFD460 Library CF (Link to library) Clone ID CFD460 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-C/CFD460Q.Seq.d/ Representative seq. ID CFD46...0F (Link to Original site) Representative DNA sequence >CFD460 (CFD460Q) /CSM/CF/CFD4-C/CFD460Q.Seq.d/ AAATA...PQWPARNHATAL RAGTVSFYLSPKMTSDAPADPSQDVFFQNSIHSSPFGNCTKYYENTNNATCTACFDLPMD ISPGLYI

  5. Dicty_cDB: CFD525 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD525 (Link to dictyBase) - - - Contig-U16366-1 CFD525P (Link to Original site) CFD5...25F 531 CFD525Z 540 CFD525P 1071 - - Show CFD525 Library CF (Link to library) Clone ID CFD5...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-B/CFD525Q.Seq.d/ Representative seq. ID CFD5...25P (Link to Original site) Representative DNA sequence >CFD525 (CFD525Q) /CSM/CF/CFD5-B/CFD5...kfqhlnllrvi pp Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD525 (CFD525Q) /CSM/CF/CFD5

  6. Dicty_cDB: CFD791 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD791 (Link to dictyBase) - - - Contig-U16368-1 CFD791P (Link to Original site) CFD...791F 599 CFD791Z 357 CFD791P 956 - - Show CFD791 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD7-D/CFD791Q.Seq.d/ Representative seq. ID CFD...791P (Link to Original site) Representative DNA sequence >CFD791 (CFD791Q) /CSM/CF/CFD7-D/CFD7...lasmic reticulum >> prediction for CFD791 is exc 5' end seq. ID CFD791F 5' end seq. >CFD

  7. Dicty_cDB: CFD250 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD250 (Link to dictyBase) - - - Contig-U16455-1 CFD250P (Link to Original site) CFD...250F 566 CFD250Z 716 CFD250P 1282 - - Show CFD250 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-C/CFD250Q.Seq.d/ Representative seq. ID CFD...250P (Link to Original site) Representative DNA sequence >CFD250 (CFD250Q) /CSM/CF/CFD2-C/CFD...hqinrqespr*sr**ercccxskxeinx*k k Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD250 (CFD

  8. Dicty_cDB: CFD196 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD196 (Link to dictyBase) - - - Contig-U15664-1 CFD196Z (Link... to Original site) - - CFD196Z 567 - - - - Show CFD196 Library CF (Link to library) Clone ID CFD196 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD1-D/CFD196Q.Seq.d/ Representative seq. ID CFD19...6Z (Link to Original site) Representative DNA sequence >CFD196 (CFD196Q) /CSM/CF/CFD1-D/CFD196Q.Seq.d/ XXXXX...lenkv Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD196 (CFD196Q) /CSM/CF/CFD1-D/CFD

  9. Dicty_cDB: CFD743 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD743 (Link to dictyBase) - - - Contig-U11615-1 CFD743F (Link to Original site) CFD...743F 655 - - - - - - Show CFD743 Library CF (Link to library) Clone ID CFD743 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD7-B/CFD743Q.Seq.d/ Representative seq. ID CFD74...3F (Link to Original site) Representative DNA sequence >CFD743 (CFD743Q) /CSM/CF/CFD7-B/CFD743Q.Seq.d/ ATGGA...mology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD743 (CFD743Q) /CSM/CF/CFD7-B/CFD

  10. Dicty_cDB: CFD559 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD559 (Link to dictyBase) - - - Contig-U11472-1 CFD559F (Link to Original site) CFD...559F 615 - - - - - - Show CFD559 Library CF (Link to library) Clone ID CFD559 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-C/CFD559Q.Seq.d/ Representative seq. ID CFD55...9F (Link to Original site) Representative DNA sequence >CFD559 (CFD559Q) /CSM/CF/CFD5-C/CFD559Q.Seq.d/ CTAAA...TDQTLDN--- Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD559 (CFD559Q) /CSM/CF/CFD5-C/CFD

  11. Dicty_cDB: CFD107 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD107 (Link to dictyBase) - - - Contig-U16347-1 CFD107Z (Link... to Original site) - - CFD107Z 654 - - - - Show CFD107 Library CF (Link to library) Clone ID CFD107 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD1-A/CFD107Q.Seq.d/ Representative seq. ID CFD10...7Z (Link to Original site) Representative DNA sequence >CFD107 (CFD107Q) /CSM/CF/CFD1-A/CFD107Q.Seq.d/ XXXXX...ogy vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD107 (CFD107Q) /CSM/CF/CFD1-A/CFD

  12. Dicty_cDB: CFD881 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD881 (Link to dictyBase) - - - Contig-U14953-1 CFD881F (Link to Original site) CFD...881F 652 - - - - - - Show CFD881 Library CF (Link to library) Clone ID CFD881 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-D/CFD881Q.Seq.d/ Representative seq. ID CFD88...1F (Link to Original site) Representative DNA sequence >CFD881 (CFD881Q) /CSM/CF/CFD8-D/CFD881Q.Seq.d/ AAATG...s CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD881 (CFD881Q) /CSM/CF/CFD8-D/CFD

  13. Dicty_cDB: CFD843 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD843 (Link to dictyBase) - - - Contig-U15554-1 CFD843P (Link to Original site) CFD...843F 551 CFD843Z 529 CFD843P 1080 - - Show CFD843 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-B/CFD843Q.Seq.d/ Representative seq. ID CFD...843P (Link to Original site) Representative DNA sequence >CFD843 (CFD843Q) /CSM/CF/CFD8-B/CFD...ei*k*mv*i**s*chrtyr*ry*ktfrww*fpyll Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD843 (CFD

  14. Dicty_cDB: CFD440 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD440 (Link to dictyBase) - - - Contig-U10797-1 CFD440P (Link to Original site) CFD...440F 648 CFD440Z 431 CFD440P 1079 - - Show CFD440 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-B/CFD440Q.Seq.d/ Representative seq. ID CFD...440P (Link to Original site) Representative DNA sequence >CFD440 (CFD440Q) /CSM/CF/CFD4-B/CFD...IALVEI SKLNHYTGRNEPNVIT*inkf**tkk Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD440 (CFD

  15. Dicty_cDB: CFD632 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD632 (Link to dictyBase) - - - Contig-U15640-1 CFD632F (Link to Original site) CFD...632F 603 - - - - - - Show CFD632 Library CF (Link to library) Clone ID CFD632 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-B/CFD632Q.Seq.d/ Representative seq. ID CFD63...2F (Link to Original site) Representative DNA sequence >CFD632 (CFD632Q) /CSM/CF/CFD6-B/CFD632Q.Seq.d/ AAAAG....Seq.d/ 66 7e-10 CFH442 (CFH442Q) /CSM/CF/CFH4-B/CFH442Q.Seq.d/ 66 7e-10 CFD632 (CFD632Q) /CSM/CF/CFD6-B/CFD

  16. Dicty_cDB: CFD360 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD360 (Link to dictyBase) - - - Contig-U16465-1 CFD360Z (Link... to Original site) - - CFD360Z 474 - - - - Show CFD360 Library CF (Link to library) Clone ID CFD360 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-C/CFD360Q.Seq.d/ Representative seq. ID CFD36...0Z (Link to Original site) Representative DNA sequence >CFD360 (CFD360Q) /CSM/CF/CFD3-C/CFD360Q.Seq.d/ XXXXX...E Sequences producing significant alignments: (bits) Value CFD360 (CFD360Q) /CSM/CF/CFD3-C/CFD360Q.Seq.d/ 94

  17. Dicty_cDB: CFD318 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD318 (Link to dictyBase) - - - Contig-U11167-1 CFD318F (Link to Original site) CFD...318F 611 - - - - - - Show CFD318 Library CF (Link to library) Clone ID CFD318 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-A/CFD318Q.Seq.d/ Representative seq. ID CFD31...8F (Link to Original site) Representative DNA sequence >CFD318 (CFD318Q) /CSM/CF/CFD3-A/CFD318Q.Seq.d/ TAAAT...- Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD318 (CFD318Q) /CSM/CF/CFD3-A/CFD

  18. Dicty_cDB: CFD648 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD648 (Link to dictyBase) - - - Contig-U16368-1 CFD648F (Link to Original site) CFD...648F 552 - - - - - - Show CFD648 Library CF (Link to library) Clone ID CFD648 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-B/CFD648Q.Seq.d/ Representative seq. ID CFD64...8F (Link to Original site) Representative DNA sequence >CFD648 (CFD648Q) /CSM/CF/CFD6-B/CFD648Q.Seq.d/ ATTCA...Sequences producing significant alignments: (bits) Value CFD648 (CFD648Q) /CSM/CF/CFD6-B/CFD648Q.Seq.d/ 954

  19. Dicty_cDB: CFD860 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD860 (Link to dictyBase) - - - Contig-U11146-1 CFD860F (Link to Original site) CFD...860F 608 - - - - - - Show CFD860 Library CF (Link to library) Clone ID CFD860 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-C/CFD860Q.Seq.d/ Representative seq. ID CFD86...0F (Link to Original site) Representative DNA sequence >CFD860 (CFD860Q) /CSM/CF/CFD8-C/CFD860Q.Seq.d/ AAAAA...ogy vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD860 (CFD860Q) /CSM/CF/CFD8-C/CFD

  20. Dicty_cDB: CFD696 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD696 (Link to dictyBase) - - - Contig-U15456-1 CFD696F (Link to Original site) CFD...696F 553 - - - - - - Show CFD696 Library CF (Link to library) Clone ID CFD696 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-D/CFD696Q.Seq.d/ Representative seq. ID CFD69...6F (Link to Original site) Representative DNA sequence >CFD696 (CFD696Q) /CSM/CF/CFD6-D/CFD696Q.Seq.d/ AATTT...F810Q) /CSM/CF/CFF8-A/CFF810Q.Seq.d/ 1055 0.0 CFD696 (CFD696Q) /CSM/CF/CFD6-D/CFD696Q.Seq.d/ 1055 0.0 CFB887

  1. Dicty_cDB: CFD785 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD785 (Link to dictyBase) - - - Contig-U15635-1 CFD785F (Link to Original site) CFD...785F 595 - - - - - - Show CFD785 Library CF (Link to library) Clone ID CFD785 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD7-D/CFD785Q.Seq.d/ Representative seq. ID CFD78...5F (Link to Original site) Representative DNA sequence >CFD785 (CFD785Q) /CSM/CF/CFD7-D/CFD785Q.Seq.d/ AAAAT...F/SFB4-D/SFB492Q.Seq.d/ 1066 0.0 CHA557 (CHA557Q) /CSM/CH/CHA5-C/CHA557Q.Seq.d/ 1066 0.0 CFD785 (CFD785Q) /CSM/CF/CFD7-D/CFD

  2. Dicty_cDB: CFD371 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD371 (Link to dictyBase) - - - Contig-U15889-1 CFD371Z (Link... to Original site) - - CFD371Z 550 - - - - Show CFD371 Library CF (Link to library) Clone ID CFD371 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-C/CFD371Q.Seq.d/ Representative seq. ID CFD37...1Z (Link to Original site) Representative DNA sequence >CFD371 (CFD371Q) /CSM/CF/CFD3-C/CFD371Q.Seq.d/ XXXXX...nces producing significant alignments: (bits) Value CFD371 (CFD371Q) /CSM/CF/CFD3-C/CFD371Q.Seq.d/ 1049 0.0

  3. Dicty_cDB: CFD619 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD619 (Link to dictyBase) - - - Contig-U10064-1 CFD619F (Link to Original site) CFD...619F 692 - - - - - - Show CFD619 Library CF (Link to library) Clone ID CFD619 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-A/CFD619Q.Seq.d/ Representative seq. ID CFD61...9F (Link to Original site) Representative DNA sequence >CFD619 (CFD619Q) /CSM/CF/CFD6-A/CFD619Q.Seq.d/ AGCTA...M/VF/VFD7-C/VFD756Q.Seq.d/ 1372 0.0 VFB639 (VFB639Q) /CSM/VF/VFB6-B/VFB639Q.Seq.d/ 1372 0.0 CFD619 (CFD619Q) /CSM/CF/CFD6-A/CFD

  4. Dicty_cDB: CFD711 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD711 (Link to dictyBase) - - - Contig-U15331-1 CFD711P (Link to Original site) CFD...711F 573 CFD711Z 239 CFD711P 812 - - Show CFD711 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD7-A/CFD711Q.Seq.d/ Representative seq. ID CFD...711P (Link to Original site) Representative DNA sequence >CFD711 (CFD711Q) /CSM/CF/CFD7-A/CFD7...logy vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD711 (CFD

  5. Dicty_cDB: CFD882 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD882 (Link to dictyBase) - - - Contig-U16511-1 CFD882Z (Link... to Original site) - - CFD882Z 315 - - - - Show CFD882 Library CF (Link to library) Clone ID CFD882 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-D/CFD882Q.Seq.d/ Representative seq. ID CFD88...2Z (Link to Original site) Representative DNA sequence >CFD882 (CFD882Q) /CSM/CF/CFD8-D/CFD882Q.Seq.d/ XXXXX...Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD882 (CFD882Q) /CSM/CF/CFD8-D/CFD

  6. Dicty_cDB: CFD586 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD586 (Link to dictyBase) - - - Contig-U12859-1 CFD586F (Link to Original site) CFD...586F 579 - - - - - - Show CFD586 Library CF (Link to library) Clone ID CFD586 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-D/CFD586Q.Seq.d/ Representative seq. ID CFD58...6F (Link to Original site) Representative DNA sequence >CFD586 (CFD586Q) /CSM/CF/CFD5-D/CFD586Q.Seq.d/ AATTT...FE647 (CFE647Q) /CSM/CF/CFE6-B/CFE647Q.Seq.d/ 1082 0.0 CFD586 (CFD586Q) /CSM/CF/CFD5-D/CFD586Q.Seq.d/ 1082 0

  7. Dicty_cDB: CFD456 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD456 (Link to dictyBase) - - - Contig-U15606-1 CFD456F (Link to Original site) CFD...456F 553 - - - - - - Show CFD456 Library CF (Link to library) Clone ID CFD456 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-C/CFD456Q.Seq.d/ Representative seq. ID CFD45...6F (Link to Original site) Representative DNA sequence >CFD456 (CFD456Q) /CSM/CF/CFD4-C/CFD456Q.Seq.d/ ATTAT...E Sequences producing significant alignments: (bits) Value CFD456 (CFD456Q) /CSM/CF/CFD4-C/CFD456Q.Seq.d/ 86

  8. Dicty_cDB: CFD319 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD319 (Link to dictyBase) - - - Contig-U16511-1 CFD319Z (Link... to Original site) - - CFD319Z 485 - - - - Show CFD319 Library CF (Link to library) Clone ID CFD319 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-A/CFD319Q.Seq.d/ Representative seq. ID CFD31...9Z (Link to Original site) Representative DNA sequence >CFD319 (CFD319Q) /CSM/CF/CFD3-A/CFD319Q.Seq.d/ XXXXX...mology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD319 (CFD319Q) /CSM/CF/CFD3-A/CFD

  9. Dicty_cDB: CFD113 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD113 (Link to dictyBase) - - - Contig-U15664-1 CFD113Z (Link... to Original site) - - CFD113Z 542 - - - - Show CFD113 Library CF (Link to library) Clone ID CFD113 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD1-A/CFD113Q.Seq.d/ Representative seq. ID CFD11...3Z (Link to Original site) Representative DNA sequence >CFD113 (CFD113Q) /CSM/CF/CFD1-A/CFD113Q.Seq.d/ XXXXX...ificant alignments: (bits) Value CFD113 (CFD113Q) /CSM/CF/CFD1-A/CFD113Q.Seq.d/ 1063 0.0 AFA127 (AFA127Q) /C

  10. Dicty_cDB: CFD459 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD459 (Link to dictyBase) - - - Contig-U16368-1 CFD459F (Link to Original site) CFD...459F 356 - - - - - - Show CFD459 Library CF (Link to library) Clone ID CFD459 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-C/CFD459Q.Seq.d/ Representative seq. ID CFD45...9F (Link to Original site) Representative DNA sequence >CFD459 (CFD459Q) /CSM/CF/CFD4-C/CFD459Q.Seq.d/ ATTCA... vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD459 (CFD459Q) /CSM/CF/CFD4-C/CFD

  11. Dicty_cDB: CFD442 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD442 (Link to dictyBase) - - - Contig-U16447-1 CFD442F (Link to Original site) CFD...442F 629 - - - - - - Show CFD442 Library CF (Link to library) Clone ID CFD442 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-B/CFD442Q.Seq.d/ Representative seq. ID CFD44...2F (Link to Original site) Representative DNA sequence >CFD442 (CFD442Q) /CSM/CF/CFD4-B/CFD442Q.Seq.d/ AATTC.../CSM/CF/CFK2-D/CFK279Q.Seq.d/ 1247 0.0 CFD442 (CFD442Q) /CSM/CF/CFD4-B/CFD442Q.Seq.d/ 1247 0.0 own update 20

  12. Dicty_cDB: CFD847 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD847 (Link to dictyBase) - - - Contig-U16254-1 CFD847P (Link to Original site) CFD...847F 645 CFD847Z 133 CFD847P 778 - - Show CFD847 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-B/CFD847Q.Seq.d/ Representative seq. ID CFD...847P (Link to Original site) Representative DNA sequence >CFD847 (CFD847Q) /CSM/CF/CFD8-B/CFD8...igslvgly*elsqaissnv Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD847 (CFD

  13. Dicty_cDB: CFD588 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD588 (Link to dictyBase) - - - Contig-U11056-1 CFD588F (Link to Original site) CFD...588F 564 - - - - - - Show CFD588 Library CF (Link to library) Clone ID CFD588 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-D/CFD588Q.Seq.d/ Representative seq. ID CFD58...8F (Link to Original site) Representative DNA sequence >CFD588 (CFD588Q) /CSM/CF/CFD5-D/CFD588Q.Seq.d/ ATATT...omology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD588 (CFD588Q) /CSM/CF/CFD5-D/CFD

  14. Dicty_cDB: CFD331 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD331 (Link to dictyBase) - - - Contig-U16347-1 CFD331Z (Link... to Original site) - - CFD331Z 589 - - - - Show CFD331 Library CF (Link to library) Clone ID CFD331 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-B/CFD331Q.Seq.d/ Representative seq. ID CFD33...1Z (Link to Original site) Representative DNA sequence >CFD331 (CFD331Q) /CSM/CF/CFD3-B/CFD331Q.Seq.d/ XXXXX...gnificant alignments: (bits) Value CFD331 (CFD331Q) /CSM/CF/CFD3-B/CFD331Q.Seq.d/ 1098 0.0 CFE201 (CFE201Q)

  15. Dicty_cDB: CFD616 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD616 (Link to dictyBase) - - - Contig-U12597-1 CFD616F (Link to Original site) CFD...616F 105 - - - - - - Show CFD616 Library CF (Link to library) Clone ID CFD616 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-A/CFD616Q.Seq.d/ Representative seq. ID CFD61...6F (Link to Original site) Representative DNA sequence >CFD616 (CFD616Q) /CSM/CF/CFD6-A/CFD616Q.Seq.d/ AATAA...M/CF/CFH8-C/CFH861Q.Seq.d/ 82 2e-15 CFG565 (CFG565Q) /CSM/CF/CFG5-C/CFG565Q.Seq.d/ 82 2e-15 CFD616 (CFD616Q) /CSM/CF/CFD6-A/CFD

  16. Dicty_cDB: CFD831 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD831 (Link to dictyBase) - - - Contig-U07842-1 CFD831F (Link to Original site) CFD...831F 597 - - - - - - Show CFD831 Library CF (Link to library) Clone ID CFD831 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-B/CFD831Q.Seq.d/ Representative seq. ID CFD83...1F (Link to Original site) Representative DNA sequence >CFD831 (CFD831Q) /CSM/CF/CFD8-B/CFD831Q.Seq.d/ ATTTA...quences producing significant alignments: (bits) Value CFD831 (CFD831Q) /CSM/CF/CFD8-B/CFD831Q.Seq.d/ 1183 0

  17. CFD analysis of turbopump volutes

    Science.gov (United States)

    Ascoli, Edward P.; Chan, Daniel C.; Darian, Armen; Hsu, Wayne W.; Tran, Ken

    1993-07-01

    An effort is underway to develop a procedure for the regular use of CFD analysis in the design of turbopump volutes. Airflow data to be taken at NASA Marshall will be used to validate the CFD code and overall procedure. Initial focus has been on preprocessing (geometry creation, translation, and grid generation). Volute geometries have been acquired electronically and imported into the CATIA CAD system and RAGGS (Rockwell Automated Grid Generation System) via the IGES standard. An initial grid topology has been identified and grids have been constructed for turbine inlet and discharge volutes. For CFD analysis of volutes to be used regularly, a procedure must be defined to meet engineering design needs in a timely manner. Thus, a compromise must be established between making geometric approximations, the selection of grid topologies, and possible CFD code enhancements. While the initial grid developed approximated the volute tongue with a zero thickness, final computations should more accurately account for the geometry in this region. Additionally, grid topologies will be explored to minimize skewness and high aspect ratio cells that can affect solution accuracy and slow code convergence. Finally, as appropriate, code modifications will be made to allow for new grid topologies in an effort to expedite the overall CFD analysis process.

  18. CFD Analysis of an Aerofoil

    Directory of Open Access Journals (Sweden)

    Karna S. Patel

    2014-03-01

    Full Text Available In this report we have obtained the drag and lift forces using CFD which can also be determined through experiments using wind tunnel testing. In experimental setup, the design model has to be placed in the test section. This process is quite laborious & (surely cost more than CFD techniques cost for the same. Thus we have gone through analytical method then it can be validated by experimental testing. The analysis of the two dimensional subsonic flow over a NACA 0012 airfoil at various angles of attack and operating at a Reynolds number of 3×E+06 is presented. The CFD simulation results show close agreement with those of the experiments, thus suggesting a reliable alternative to experimental method in determining drag and lift.

  19. CFD Analysis of Centrifugal Pump: A Review

    OpenAIRE

    Narayan P. Jaiswal

    2014-01-01

    The main objective of this work is to understand role of the computational fluid dynamics (CFD) technique in analyzing and predicting the performance of centrifugal pump. Computational Fluid Dynamics (CFD) is the present day state-of-art technique for fluid flow analysis. The critical review of CFD analysis of CFD analysis of centrifugal pump along with future scope for further improvement is presented in this paper. Different solver like ANSYS-CFX, FLUENT etc can be used for ...

  20. Dicty_cDB: CFD155 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD155 (Link to dictyBase) - - - Contig-U16255-1 CFD155Z (Link... to Original site) - - CFD155Z 527 - - - - Show CFD155 Library CF (Link to library) Clone ID CFD155 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD1-C/CFD155Q.Seq.d/ Representative seq. ID CFD15...5Z (Link to Original site) Representative DNA sequence >CFD155 (CFD155Q) /CSM/CF/CFD1-C/CFD155Q.Seq.d/ XXXXX... CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD155 (CFD155Q) /CSM/CF/CFD

  1. Dicty_cDB: CFD833 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD833 (Link to dictyBase) - - - Contig-U16560-1 CFD833F (Link to Original site) CFD...833F 120 - - - - - - Show CFD833 Library CF (Link to library) Clone ID CFD833 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-B/CFD833Q.Seq.d/ Representative seq. ID CFD83...3F (Link to Original site) Representative DNA sequence >CFD833 (CFD833Q) /CSM/CF/CFD8-B/CFD833Q.Seq.d/ AAAAT...4.0 %: peroxisomal >> prediction for CFD833 is cyt 5' end seq. ID CFD833F 5' end seq. >CFD

  2. Dicty_cDB: CFD283 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD283 (Link to dictyBase) - - - Contig-U10672-1 CFD283P (Link to Original site) CFD...283F 569 CFD283Z 547 CFD283P 1116 - - Show CFD283 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-D/CFD283Q.Seq.d/ Representative seq. ID CFD...283P (Link to Original site) Representative DNA sequence >CFD283 (CFD283Q) /CSM/CF/CFD2-D/CFD...GXSYFISTIN *fit Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD

  3. Dicty_cDB: CFD409 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD409 (Link to dictyBase) - - - Contig-U12865-1 CFD409Z (Link... to Original site) - - CFD409Z 196 - - - - Show CFD409 Library CF (Link to library) Clone ID CFD409 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-A/CFD409Q.Seq.d/ Representative seq. ID CFD40...9Z (Link to Original site) Representative DNA sequence >CFD409 (CFD409Q) /CSM/CF/CFD4-A/CFD409Q.Seq.d/ XXXXX...kx*cqtkny sr*ip** Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD409 (CFD409Q) /CSM/CF/CFD

  4. Dicty_cDB: CFD327 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD327 (Link to dictyBase) - - - Contig-U16560-1 CFD327F (Link to Original site) CFD...327F 113 - - - - - - Show CFD327 Library CF (Link to library) Clone ID CFD327 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-B/CFD327Q.Seq.d/ Representative seq. ID CFD32...7F (Link to Original site) Representative DNA sequence >CFD327 (CFD327Q) /CSM/CF/CFD3-B/CFD327Q.Seq.d/ ATTTT....0 %: peroxisomal >> prediction for CFD327 is cyt 5' end seq. ID CFD327F 5' end seq. >CFD

  5. Dicty_cDB: CFD580 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD580 (Link to dictyBase) - - - Contig-U16368-1 CFD580F (Link to Original site) CFD...580F 516 - - - - - - Show CFD580 Library CF (Link to library) Clone ID CFD580 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-D/CFD580Q.Seq.d/ Representative seq. ID CFD58...0F (Link to Original site) Representative DNA sequence >CFD580 (CFD580Q) /CSM/CF/CFD5-D/CFD580Q.Seq.d/ AAATA...: vacuolar 4.0 %: mitochondrial 4.0 %: nuclear >> prediction for CFD580 is exc 5' end seq. ID CFD580F 5' end seq. >CFD

  6. Dicty_cDB: CFD807 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD807 (Link to dictyBase) - - - Contig-U10800-1 CFD807F (Link to Original site) CFD...807F 570 - - - - - - Show CFD807 Library CF (Link to library) Clone ID CFD807 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-A/CFD807Q.Seq.d/ Representative seq. ID CFD80...7F (Link to Original site) Representative DNA sequence >CFD807 (CFD807Q) /CSM/CF/CFD8-A/CFD807Q.Seq.d/ ATTAA...pisiillsl--- Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD807 (CFD807Q) /CSM/CF/CFD

  7. Dicty_cDB: CFD654 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD654 (Link to dictyBase) - - - Contig-U16602-1 CFD654F (Link to Original site) CFD...654F 570 - - - - - - Show CFD654 Library CF (Link to library) Clone ID CFD654 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-C/CFD654Q.Seq.d/ Representative seq. ID CFD65...4F (Link to Original site) Representative DNA sequence >CFD654 (CFD654Q) /CSM/CF/CFD6-C/CFD654Q.Seq.d/ AATTC... system 4.0 %: peroxisomal >> prediction for CFD654 is cyt 5' end seq. ID CFD654F 5' end seq. >CFD

  8. Dicty_cDB: CFD623 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD623 (Link to dictyBase) - - - Contig-U16450-1 CFD623P (Link to Original site) CFD...623F 533 CFD623Z 404 CFD623P 937 - - Show CFD623 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-A/CFD623Q.Seq.d/ Representative seq. ID CFD...623P (Link to Original site) Representative DNA sequence >CFD623 (CFD623Q) /CSM/CF/CFD6-A/CFD6...luding cell wall 24.0 %: cytoplasmic 16.0 %: mitochondrial 8.0 %: vacuolar 8.0 %: nuclear 4.0 %: cytoskeletal >> prediction for CFD

  9. Dicty_cDB: CFD726 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD726 (Link to dictyBase) - - - Contig-U11642-1 CFD726P (Link to Original site) CFD...726F 545 CFD726Z 570 CFD726P 1115 - - Show CFD726 Library CF (Link to library) Clone ID CFD...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD7-B/CFD726Q.Seq.d/ Representative seq. ID CFD...726P (Link to Original site) Representative DNA sequence >CFD726 (CFD726Q) /CSM/CF/CFD7-B/CFD...x *ncflcxqlin* Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD

  10. Dicty_cDB: CFD508 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD508 (Link to dictyBase) - - - Contig-U15817-1 CFD508F (Link to Original site) CFD...508F 516 - - - - - - Show CFD508 Library CF (Link to library) Clone ID CFD508 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-A/CFD508Q.Seq.d/ Representative seq. ID CFD50...8F (Link to Original site) Representative DNA sequence >CFD508 (CFD508Q) /CSM/CF/CFD5-A/CFD508Q.Seq.d/ ATAGT...ic reticulum >> prediction for CFD508 is cyt 5' end seq. ID CFD508F 5' end seq. >CFD508F.Seq ATAGTTATTTAAATA

  11. Dicty_cDB: CFD130 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD130 (Link to dictyBase) - G03006 DDB0191258 Contig-U16598-1 CFD...130P (Link to Original site) CFD130F 529 CFD130Z 445 CFD130P 974 - - Show CFD130 Library CF (Link to library) Clone ID CFD...ontig-U16598-1 Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD1-B/CFD...130Q.Seq.d/ Representative seq. ID CFD130P (Link to Original site) Representative DNA sequence >CFD130 (CFD130Q) /CSM/CF/CFD...Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD130 (CFD

  12. Dicty_cDB: CFD684 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD684 (Link to dictyBase) - - - Contig-U12597-1 CFD684F (Link to Original site) CFD...684F 128 - - - - - - Show CFD684 Library CF (Link to library) Clone ID CFD684 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-D/CFD684Q.Seq.d/ Representative seq. ID CFD68...4F (Link to Original site) Representative DNA sequence >CFD684 (CFD684Q) /CSM/CF/CFD6-D/CFD684Q.Seq.d/ ATATA...: cytoskeletal 8.0 %: mitochondrial 8.0 %: cytoplasmic >> prediction for CFD684 is nuc 5' end seq. ID CFD684F 5' end seq. >CFD

  13. Dicty_cDB: CFD758 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD758 (Link to dictyBase) - - - Contig-U16455-1 CFD758F (Link to Original site) CFD...758F 570 - - - - - - Show CFD758 Library CF (Link to library) Clone ID CFD758 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD7-C/CFD758Q.Seq.d/ Representative seq. ID CFD75...8F (Link to Original site) Representative DNA sequence >CFD758 (CFD758Q) /CSM/CF/CFD7-C/CFD758Q.Seq.d/ AAATT...qrsfifh*k--- Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD758 (CFD758Q) /CSM/CF/CFD

  14. Dicty_cDB: CFD131 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD131 (Link to dictyBase) - - - Contig-U09897-1 CFD131P (Link to Original site) CFD...131F 581 CFD131Z 205 CFD131P 786 - - Show CFD131 Library CF (Link to library) Clone ID CFD... URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD1-B/CFD131Q.Seq.d/ Representative seq. ID CFD...131P (Link to Original site) Representative DNA sequence >CFD131 (CFD131Q) /CSM/CF/CFD1-B/CFD1...QKKLIXFKVPKKIIITDNFPKTASGKIQRR FIADXLLKQQ Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD

  15. Integrating CFD and building simulation

    DEFF Research Database (Denmark)

    Bartak, M.; Beausoleil-Morrison, I.; Clarke, J.A.;

    2002-01-01

    To provide practitioners with the means to tackle problems related to poor indoor environments, building simulation and computational 3uid dynamics can usefully be integrated within a single computational framework. This paper describes the outcomes from a research project sponsored by the European...... Commission, which furthered the CFD modelling aspects of the ESP-r system. The paper summarises the form of the CFD model, describes the method used to integrate the thermal and 3ow domains and reports the outcome from an empirical validation exercise. © 2002 Published by Elsevier Science Ltd....

  16. Perspectivas del potencial energético de la biomasa en el marco global y latinoamericano

    Directory of Open Access Journals (Sweden)

    Julián Rodrigo Quintero González

    2015-06-01

    Full Text Available El calentamiento global y los cambios climáticos que éste conlleva han fomentado desde hace algunos años la exploración de otros tipos de obtención energética para disminuir el uso del combustible fósil, siendo éste último uno de los principales causantes de dicho problema ambiental. El presente artículo expone algunas investigaciones recientes sobre la bioenergía u obtención de energía a partir de biomasa, considerada como energía limpia. Se abarcan temáticas como la bioenergía y sus posibilidades desde el punto de vista energético, teniendo en cuenta las expectativas de producción según su potencial o productividad energética, además del aporte que este tipo de tecnología hace a la disminución de la huella ecológica.

  17. Obtención de etanol a partir de biomasa lignocelulósica

    Directory of Open Access Journals (Sweden)

    Mabel Viñals-Verde

    2012-01-01

    Full Text Available Se muestra el estado de la literatura en cuanto a la obtención de etanol a partir de hidrolizados lignocelulósicos, una alternativa muy estudiada en la actualidad en el mundo con vistas a disminuir el costo del etanol combustible. Se reportan los materiales lignocelulósicos que están en estudio siendo el bagazo de caña de azúcar y los derivados del maíz los más utilizados. Se presentan los métodos de pre-tratamiento, purificación del hidrolizado, fraccionamiento de la celulosa, obtención de microorganismos geneticamente modificados y producción a nivel de planta piloto e industrial. Los métodos de pretratamiento por explosión por vapor y de purificación por "overliming" son los más estudiados con resultados satisfactorios. Entre los métodos de fraccionamiento de la celulosa, la sacarificación y fermentación simultáneas (SSF se reporta como el proceso más novedoso y eficiente para la obtención de etanol a partir de biomasa aunque a nivel de planta piloto e industrial se continúa trabajando con el sistema de hidrólisis ácida. Se muestran algunos resultados obtenidos con microorganismos genéticamente modificados como la levadura Saccharomyces y la bacteria Escherichia coli.

  18. Dicty_cDB: CFD641 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD641 (Link to dictyBase) - - - - CFD641P (Link to Original site) CFD641F 591 CFD...641Z 405 CFD641P 996 - - Show CFD641 Library CF (Link to library) Clone ID CFD641 (Link ...to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig - Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD...6-B/CFD641Q.Seq.d/ Representative seq. ID CFD641P (Link to ...Original site) Representative DNA sequence >CFD641 (CFD641Q) /CSM/CF/CFD6-B/CFD641Q.Seq.d/ ATTATTGTTAAAATAAG

  19. Dicty_cDB: CFD217 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD217 (Link to dictyBase) - - - - CFD217P (Link to Original site) CFD217F 882 CFD...217Z 869 CFD217P 1751 - - Show CFD217 Library CF (Link to library) Clone ID CFD217 (Link... to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig - Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD...2-A/CFD217Q.Seq.d/ Representative seq. ID CFD217P (Link to... Original site) Representative DNA sequence >CFD217 (CFD217Q) /CSM/CF/CFD2-A/CFD217Q.Seq.d/ TTTACATATTAATTAA

  20. Dicty_cDB: CFD665 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD665 (Link to dictyBase) - - - Contig-U16255-1 CFD665Z (Link... to Original site) - - CFD665Z 426 - - - - Show CFD665 Library CF (Link to library) Clone ID CFD665 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-C/CFD665Q.Seq.d/ Representative seq. ID CFD66...5Z (Link to Original site) Representative DNA sequence >CFD665 (CFD665Q) /CSM/CF/CFD6-C/CFD665Q.Seq.d/ XXXXX...oskeletal >> prediction for CFD665 is nuc 5' end seq. ID - 5' end seq. - Length of 5' end seq. - 3' end seq. ID CFD

  1. Dicty_cDB: CFD710 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD710 (Link to dictyBase) - - - Contig-U16381-1 CFD710F (Link to Original site) CFD...710F 121 - - - - - - Show CFD710 Library CF (Link to library) Clone ID CFD710 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD7-A/CFD710Q.Seq.d/ Representative seq. ID CFD71...0F (Link to Original site) Representative DNA sequence >CFD710 (CFD710Q) /CSM/CF/CFD7-A/CFD710Q.Seq.d/ GTAGT...233,276 protein update 2009. 5.13 PSORT - 5' end seq. ID CFD710F 5' end seq. >CFD710F.Seq GTAGTATTTTGTTCATAT

  2. Dicty_cDB: CFD302 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD302 (Link to dictyBase) - - - Contig-U16381-1 CFD302F (Link to Original site) CFD...302F 124 - - - - - - Show CFD302 Library CF (Link to library) Clone ID CFD302 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-A/CFD302Q.Seq.d/ Representative seq. ID CFD30...2F (Link to Original site) Representative DNA sequence >CFD302 (CFD302Q) /CSM/CF/CFD3-A/CFD302Q.Seq.d/ ATTGT...3 PSORT - 5' end seq. ID CFD302F 5' end seq. >CFD302F.Seq ATTGTAGTATTTTGTTCATATTCAAATTAAATATCAATACAATTAAAAAA

  3. Dicty_cDB: CFD509 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD509 (Link to dictyBase) - G22822 DDB0188045 Contig-U14185-1 CFD...509Z (Link to Original site) - - CFD509Z 312 - - - - Show CFD509 Library CF (Link to library) Clone ID CFD...riginal site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-A/CFD509Q.Seq.d/ ...Representative seq. ID CFD509Z (Link to Original site) Representative DNA sequence >CFD509 (CFD509Q) /CSM/CF/CFD5-A/CFD...YMMKKDTRLKQNK*inkitk Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD509 (CFD

  4. Dicty_cDB: CFD856 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD856 (Link to dictyBase) - G21749 DDB0218152 Contig-U03176-1 CFD...856F (Link to Original site) CFD856F 237 - - - - - - Show CFD856 Library CF (Link to library) Clone ID CFD...riginal site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-C/CFD856Q.Seq.d/ ...Representative seq. ID CFD856F (Link to Original site) Representative DNA sequence >CFD856 (CFD856Q) /CSM/CF/CFD8-C/CFD...n*k*k*klc** kikkrtkkkgtkgnqkpk--- Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD856 (CFD

  5. Dicty_cDB: CFD316 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD316 (Link to dictyBase) - - - Contig-U16358-1 CFD316F (Link to Original site) CFD...316F 585 - - - - - - Show CFD316 Library CF (Link to library) Clone ID CFD316 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-A/CFD316Q.Seq.d/ Representative seq. ID CFD31...6F (Link to Original site) Representative DNA sequence >CFD316 (CFD316Q) /CSM/CF/CFD3-A/CFD316Q.Seq.d/ ACAAA...lular, including cell wall 4.0 %: cytoskeletal 4.0 %: vacuolar >> prediction for CFD316 is cyt 5' end seq. ID CFD

  6. Dicty_cDB: CFD455 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD455 (Link to dictyBase) - G21745 DDB0216753 Contig-U11207-1 | Contig-U15871-1 CFD...455P (Link to Original site) CFD455F 581 CFD455Z 154 CFD455P 735 - - Show CFD455 Libra...ry CF (Link to library) Clone ID CFD455 (Link to dictyBase) Atlas ID - NBRP ID G21745 dictyBase ID DDB021675...cdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-C/CFD455Q.Seq.d/ Representative seq. ID CFD455P (Link to Original site) R...epresentative DNA sequence >CFD455 (CFD455Q) /CSM/CF/CFD4-C/CFD455Q.Seq.d/ AACAACAATAATACCAACAATAATAATCAAAGA

  7. Dicty_cDB: CFD642 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD642 (Link to dictyBase) - - - Contig-U12597-1 CFD642F (Link to Original site) CFD...642F 130 - - - - - - Show CFD642 Library CF (Link to library) Clone ID CFD642 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-B/CFD642Q.Seq.d/ Representative seq. ID CFD64...2F (Link to Original site) Representative DNA sequence >CFD642 (CFD642Q) /CSM/CF/CFD6-B/CFD642Q.Seq.d/ ATATA...ear 8.0 %: cytoskeletal 8.0 %: mitochondrial 8.0 %: cytoplasmic >> prediction for CFD642 is nuc 5' end seq. ID CFD

  8. Dicty_cDB: CFD837 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD837 (Link to dictyBase) - - - Contig-U10808-1 CFD837F (Link to Original site) CFD...837F 654 - - - - - - Show CFD837 Library CF (Link to library) Clone ID CFD837 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-B/CFD837Q.Seq.d/ Representative seq. ID CFD83...7F (Link to Original site) Representative DNA sequence >CFD837 (CFD837Q) /CSM/CF/CFD8-B/CFD837Q.Seq.d/ AAATT...0.0 SFC341 (SFC341Q) /CSM/SF/SFC3-B/SFC341Q.Seq.d/ 1128 0.0 CFE266 (CFE266Q) /CSM/CF/CFE2-C/CFE266Q.Seq.d/ 1128 0.0 CFD837 (CFD

  9. Dicty_cDB: CFD261 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD261 (Link to dictyBase) - G22821 DDB0191648 Contig-U00762-1 | Contig-U16408-1 CFD...261P (Link to Original site) CFD261F 599 CFD261Z 360 CFD261P 959 - - Show CFD261 Libra...ry CF (Link to library) Clone ID CFD261 (Link to dictyBase) Atlas ID - NBRP ID G22821 dictyBase ID DDB019164...cdb.biol.tsukuba.ac.jp/CSM/CF/CFD2-C/CFD261Q.Seq.d/ Representative seq. ID CFD261P (Link to Original site) R...epresentative DNA sequence >CFD261 (CFD261Q) /CSM/CF/CFD2-C/CFD261Q.Seq.d/ ATACTTACCTGTCAATATTAATATGTGATCACA

  10. Dicty_cDB: CFD339 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD339 (Link to dictyBase) - - - - CFD339P (Link to Original site) CFD339F 636 CFD...339Z 631 CFD339P 1267 - - Show CFD339 Library CF (Link to library) Clone ID CFD339 (Link... to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig - Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD...3-B/CFD339Q.Seq.d/ Representative seq. ID CFD339P (Link to... Original site) Representative DNA sequence >CFD339 (CFD339Q) /CSM/CF/CFD3-B/CFD339Q.Seq.d/ GGTGGTGGTACATTTG

  11. Dicty_cDB: CFD422 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD422 (Link to dictyBase) - - - Contig-U16381-1 CFD422F (Link to Original site) CFD...422F 124 - - - - - - Show CFD422 Library CF (Link to library) Clone ID CFD422 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-A/CFD422Q.Seq.d/ Representative seq. ID CFD42...2F (Link to Original site) Representative DNA sequence >CFD422 (CFD422Q) /CSM/CF/CFD4-A/CFD422Q.Seq.d/ ATTGT...DB: 74,169,940 protein update 2009. 5.13 PSORT - 5' end seq. ID CFD422F 5' end seq. >CFD422F.Seq ATTGTAGTATT

  12. Dicty_cDB: CFD188 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD188 (Link to dictyBase) - - - Contig-U16255-1 CFD188Z (Link... to Original site) - - CFD188Z 198 - - - - Show CFD188 Library CF (Link to library) Clone ID CFD188 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD1-D/CFD188Q.Seq.d/ Representative seq. ID CFD18...8Z (Link to Original site) Representative DNA sequence >CFD188 (CFD188Q) /CSM/CF/CFD1-D/CFD188Q.Seq.d/ XXXXX...****il*vityr yvderkil Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD188 (CFD

  13. Dicty_cDB: CFD875 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD875 (Link to dictyBase) - - - Contig-U16456-1 CFD875F (Link to Original site) CFD...875F 582 - - - - - - Show CFD875 Library CF (Link to library) Clone ID CFD875 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD8-D/CFD875Q.Seq.d/ Representative seq. ID CFD87...5F (Link to Original site) Representative DNA sequence >CFD875 (CFD875Q) /CSM/CF/CFD8-D/CFD875Q.Seq.d/ AAGGA...0 CFK206 (CFK206Q) /CSM/CF/CFK2-A/CFK206Q.Seq.d/ 1112 0.0 CFF387 (CFF387Q) /CSM/CF/CFF3-D/CFF387Q.Seq.d/ 1112 0.0 CFD875 (CFD

  14. Dicty_cDB: CFD815 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD815 (Link to dictyBase) - - - - CFD815P (Link to Original site) CFD815F 638 CFD...815Z 327 CFD815P 965 - - Show CFD815 Library CF (Link to library) Clone ID CFD815 (Link ...to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig - Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CF/CFD...8-A/CFD815Q.Seq.d/ Representative seq. ID CFD815P (Link to ...Original site) Representative DNA sequence >CFD815 (CFD815Q) /CSM/CF/CFD8-A/CFD815Q.Seq.d/ AATATATTCACACAACA

  15. Dicty_cDB: CFD433 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD433 (Link to dictyBase) - - - Contig-U14183-1 CFD433Z (Link... to Original site) - - CFD433Z 329 - - - - Show CFD433 Library CF (Link to library) Clone ID CFD433 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD4-B/CFD433Q.Seq.d/ Representative seq. ID CFD43...3Z (Link to Original site) Representative DNA sequence >CFD433 (CFD433Q) /CSM/CF/CFD4-B/CFD433Q.Seq.d/ XXXXX...ifiyqkiypevlssidfknfkpyqlitnqdln Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD433 (CFD

  16. Dicty_cDB: CFD348 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD348 (Link to dictyBase) - - - Contig-U16347-1 CFD348Z (Link... to Original site) - - CFD348Z 456 - - - - Show CFD348 Library CF (Link to library) Clone ID CFD348 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-B/CFD348Q.Seq.d/ Representative seq. ID CFD34...8Z (Link to Original site) Representative DNA sequence >CFD348 (CFD348Q) /CSM/CF/CFD3-B/CFD348Q.Seq.d/ XXXXX...cytoskeletal 4.0 %: vesicles of secretory system 4.0 %: endoplasmic reticulum >> prediction for CFD348 is cy

  17. Dicty_cDB: CFD668 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD668 (Link to dictyBase) - - - Contig-U16445-1 CFD668F (Link to Original site) CFD...668F 583 - - - - - - Show CFD668 Library CF (Link to library) Clone ID CFD668 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD6-C/CFD668Q.Seq.d/ Representative seq. ID CFD66...8F (Link to Original site) Representative DNA sequence >CFD668 (CFD668Q) /CSM/CF/CFD6-C/CFD668Q.Seq.d/ AATTT...vtl*ef*l*vtqpipth*lppvmhqi ltqnvslp*lv*i--- Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value CFD

  18. Dicty_cDB: CFD596 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD596 (Link to dictyBase) - - - Contig-U14178-1 CFD596F (Link to Original site) CFD...596F 367 - - - - - - Show CFD596 Library CF (Link to library) Clone ID CFD596 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD5-D/CFD596Q.Seq.d/ Representative seq. ID CFD59...6F (Link to Original site) Representative DNA sequence >CFD596 (CFD596Q) /CSM/CF/CFD5-D/CFD596Q.Seq.d/ ATTAA...) /CSM/CH/CHL6-D/CHL689Q.Seq.d/ 539 e-152 CHB303 (CHB303Q) /CSM/CH/CHB3-A/CHB303Q.Seq.d/ 539 e-152 CFD

  19. Dicty_cDB: CFD340 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD340 (Link to dictyBase) - - - Contig-U12597-1 CFD340F (Link to Original site) CFD...340F 113 - - - - - - Show CFD340 Library CF (Link to library) Clone ID CFD340 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD3-B/CFD340Q.Seq.d/ Representative seq. ID CFD34...0F (Link to Original site) Representative DNA sequence >CFD340 (CFD340Q) /CSM/CF/CFD3-B/CFD340Q.Seq.d/ ATTTA...Seq.d/ 90 8e-18 CFJ371 (CFJ371Q) /CSM/CF/CFJ3-C/CFJ371Q.Seq.d/ 90 8e-18 CFG565 (CFG565Q) /CSM/CF/CFG5-C/CFG565Q.Seq.d/ 90 8e-18 CFD

  20. Dicty_cDB: CFD135 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD135 (Link to dictyBase) - - - Contig-U16397-1 CFD135Z (Link... to Original site) - - CFD135Z 519 - - - - Show CFD135 Library CF (Link to library) Clone ID CFD135 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD1-B/CFD135Q.Seq.d/ Representative seq. ID CFD13...5Z (Link to Original site) Representative DNA sequence >CFD135 (CFD135Q) /CSM/CF/CFD1-B/CFD135Q.Seq.d/ XXXXX...vesicles of secretory system >> prediction for CFD135 is nuc 5' end seq. ID - 5' end seq. - Length of 5' end

  1. El potencial de la biomasa en España. Condicionantes para su desarrollo y viabilidad económica

    OpenAIRE

    Gregorio, Marga de

    2012-01-01

    El sector español de la biomasa es tremendamente amplio y heterogéneo, al ser un sector muy vinculado a otros sectores productivos profundamente arraigados en nuestro país, como son el agrícola, el forestal y el ganadero. La cercanía a estos sectores, y en general al medio rural, lo convierten en un sector que despierta gran interés entre los agricultores, los propietarios forestales, los ganaderos y entre los empresarios que gestionan explotaciones agroindustriales, agroganaderas, al...

  2. Estimación de Iluminación en un Fotobiorreactor Productor de Biomasa a Partir de Microalgas

    OpenAIRE

    Carlos Francisco González Hernández; Manuel de Jesús Sol Hernández; Miguel Ángel Franco Nava

    2014-01-01

    En el presente trabajo se realizó el análisis de iluminación artificial para un fotobiorreactor productor de biomasa a partir de microalgas, el cual fue diseñado previamente con fines en aplicación para la producción de biocombustibles. En el análisis, se utilizó como herramienta la técnica de contornos o también conocida como método de superficie de respuesta, para lo cual se establecieron 132 puntos de intensidad luminosa distribuidos de forma simétrica a diferentes alturas del contenedor. ...

  3. Estudio de enzimas oxidorreductasas en la transformación de biomasa lignocelulósica en biocombustibles

    OpenAIRE

    Moreno García, Antonio David

    2013-01-01

    NOTA 520 8 La transformación de la biomasa lignocelulósica mediante procesos bioquímicos consta de una etapa de pretratamiento, una etapa de hidrólisis enzimática y una etapa de fermentación. El material pretratado completo (MPC) normalmente es filtrado y lavado para obtener la fracción de residuos sólidos insolubles (RSI) rica en celulosa y lignina. Esta lignina residual supone una barrera para la hidrólisis enzimática de la celulosa y un proceso de deslignificación podría mejorar los proc...

  4. Factores del manejo para estabilizar la producción de biomasa con leguminosas en el trópico

    OpenAIRE

    T. E. Ruiz; Castillo, E.; J. Alonso; G. Febles

    2006-01-01

    Este material tiene como objetivo abundar acerca de aquellos factores del manejo que conduzcan a estabilizar la producción de biomasa en sistemas ganaderos en el trópico. Es obvio que los sistemas mejorados y bien manejados de pasturas de gramíneas y leguminosas, en cualquiera de sus alternativas, son opciones para lograr la sostenibilidad. Una concepción más amplia y profunda es la relativa a los estudios de pasturas mixtas; éstos, deben tener un enfoque más bio...

  5. Densidad y biomasa de Pterois volitans/miles (Teleostei: Scorpaenidae) en arrecifes del litoral oeste de La Habana, Cuba

    OpenAIRE

    García-Rodríguez, Alain; Chevalier Monteagudo, Pedro P.; Cabrera Sansón, Erlán; Caballero Aragón, Hansel; Luis Hernández López, Jorge

    2015-01-01

    El pez león (Pterois volitans/miles) es la primera especie (s) de pez arrecifal del Indo- Pacífico que invade el Atl{ntico Occidental, constituyendo una de las invasiones de peces marinos m{s r{pida de la historia. El objetivo fue determinar la densidad y biomasa de las poblaciones del pez león y sus posibles variaciones temporales y espaciales en arrecifes del oeste de La Habana, Cuba. Los muestreos fueron realizados mediante censos visuales con buceo autónomo en los períodos ...

  6. Control adaptable utilizando Redes Neuronales Artificiales Polinomiales

    OpenAIRE

    Gómez, E.; A. S. Poznyak; Lozano, R, R.

    2000-01-01

    Existen en la literatura de Control Adaptable, diferentes procedimientos en los que es posible identificar un sistema lineal. El problema fundamental es que una cantidad importante de fenómenos de la vida real son de tipo no lineal y no es tan sencillo el modelar este tipo de dinámicas. En este trabajo se presenta una forma de identificar sistemas no lineales utilizando las propiedades de las Redes Neuronales Artificiales y las técnicas de Algoritmo Genético en la optimización de ...

  7. Experimental Measurements and CFD Simulations

    Directory of Open Access Journals (Sweden)

    Arijit A. Ganguli

    2012-01-01

    Full Text Available Bubble dynamics of a single condensing vapor bubble in a subcooled pool boiling system with a centrally heated cylindrical tank has been studied in the Rayleigh number range 7.9×1012CFD investigation has been performed using Volume of Fluid (VOF method. The heat source has been modeled using simple heat balance. The rise behavior of condensing bubbles (change in size during rise and path tracking was studied and the CFD model was validated both quantitatively and qualitatively.

  8. Aplicación integral en construcción de materiales eco-eficientes con incorporación de cenizas de biomasa

    OpenAIRE

    Jiménez Serrano, Ivelisse

    2016-01-01

    El empleo de biomasa como combustible para la generación de bio-energía va en aumento en la actualidad, debido a su impacto medioambiental nulo en cuanto a las emisiones de CO2. Por lo tanto la generación de cenizas de biomasa, residuo de la producción de esta energía, constituye un problema medioambiental con un claro impacto social y económico. Este tipo de ceniza tiene contenidos en óxidos que la hacen atractiva para su empleo como sustituto parcial del cemento Portland, lo cual proporcion...

  9. Simulación en código Matlab de un reactor para la gasificación de biomasa en lecho fluidizado burbujeante

    OpenAIRE

    Tosina Fernández, Sergio

    2013-01-01

    Este proyecto simula un reactor unidimensional para la gasificación de biomasa supuesto en régimen estacionario, isotérmico y adiabático, con un esquema simplificado de reacciones, en el que se recogen la teoría hidrodinámica de las “Dos Fases” y distintas correlaciones y parámetros que proceden de ensayos y simulaciones de los últimos cincuenta años, aproximadamente. En los primeros capítulos del proyecto se sientan las bases y conceptos relacionados con la biomasa para una...

  10. Efecto del pretatamiento de biomasa procedente de un hábitat eutrofizado sobre la bioadsorción de metales pesados

    OpenAIRE

    Lezcano Valverde, José María

    2008-01-01

    Una vez analizado, en líneas generales, el estado actual de la investigación realizada en el área de bioadsorción, queda patente la existencia de diversos aspectos menos estudiados tales como, por ejemplo, la utilización de biomasas heterogéneas en lugar de biomasas uniespecíficas.. Otros aspectos relativamente poco estudiados, según la bibliografía, han sido los sistemas multimetálicos a pesar de ser lo más habitual en efluentes industriales. Por último, en el caso del pretratamiento de la b...

  11. Modelos para la estimación del carbono en la biomasa de los sistemas forestales : influencia de la selvicultura en los socks de carbono

    OpenAIRE

    Ruiz-Peinado Gertrudix, Ricardo

    2013-01-01

    Es ampliamente conocido y reconocido que los bosques tienen un papel fundamental en la mitigación del cambio climático. Funcionan como almacenes de carbono fijando el carbono que captan de la atmósfera en sus estructuras, conformando biomasa viva. El carbono de esta biomasa, una vez que esta muere, puede pasar de nuevo a la atmósfera o puede seguir almacenado durante años formando parte de productos forestales (madera, corcho, etc.) o en el suelo tras la descomposición de la materia orgánica....

  12. El proceso de quema de biomasa de bosque tropical y de sabanas en la Amazonia Brasilera : experiencias de monitoreo con datos ópticos y de microondas

    OpenAIRE

    dos Santos, Joáo Roberto; Pardi Lacruz, María Silvia; Spinelli de Araujo, Luciana; Magalháes Xaud, Harón Abrahim

    1998-01-01

    El presente trabajo muestra experiencias en el uso de imágenes multisensores (TM/Landsat y JERS-1) para el inventario de biomasa de formaciones forestales y de sabanas, y como herramienta del monitoreo de las quemas que ocurren en estos tipos de vegetación en la región Amazónica. Se describen procedimientos metodológicos de adquisición de datos de biomasa vegetal de porte forestal y de las sabanas. Estos datos son relacionados con las informaciones espectro-texturales de las imágenes de...

  13. Análisis de la viabilidad de una peletizadora de biomasa forestal en la Reserva de la Biosfera de la Sierra del Rincón (Madrid)

    OpenAIRE

    Romero-Calcerrada, Raúl; Manzano-Chicote, Ignacio; Novillo, Carlos J.

    2014-01-01

    En este trabajo se plantea como objetivo el análisis del aprovechamiento de biomasa forestal en la las Reservas de Biosfera (RB) de la Sierra del Rincón (Comunidad de Madrid), determinando la biomasa forestal disponible como materia prima para una planta peletizadora en La Hiruela bajo cuatro escenarios y aplicado sobre distintas áreas de aprovechamiento. Esta metodología se fundamenta en datos del Tercer Inventario Forestal Nacional, el mapa forestal, la Zonificación de la RB, un Modelo Digi...

  14. SLURRY FLOW MODELLING BY CFD

    Directory of Open Access Journals (Sweden)

    K.C. Ghanta

    2010-12-01

    Full Text Available An attempt has been made in the present study to develop a generalized slurry flow model using CFD and utilize the model to predict concentration profile. The purpose of the CFD model is to gain better insight into the solid liquid slur¬ry flow in pipelines. Initially a three-dimensional model problem was developed to understand the influence of the particle drag coefficient on the solid concen¬tration profile. The preliminary simulations highlighted the need for correct mo¬delling of the inter phase drag force. The various drag correlations available in the literature were incorporated into a two-fluid model (Euler-Euler along with the standard k- turbulence model with mixture properties to simulate the tur¬bulent solid-liquid flow in a pipeline. The computational model was mapped on to a commercial CFD solver FLUENT6.2 (of Fluent Inc., USA. To push the en¬velope of applicability of the simulation, recent data from Kaushal (2005 (with solid concentration up to 50% was selected to validate the three dimensional simulations. The experimental data consisted of water-glass bead slurry at 125 and 440-micron particle with different flow velocity (from 1 to 5 m/s and overall concentration up to 10 to 50% by volume. The predicted pressure drop and concentration profile were validated by experimental data and showed excel-lent agreement. Interesting findings came out from the parametric study of ve-locity and concentration profiles. The computational model and results discus¬sed in this work would be useful for extending the applications of CFD models for simulating large slurry pipelines.

  15. CFD ANALYSIS OF FRANCIS TURBINE

    Directory of Open Access Journals (Sweden)

    Ravindra R. Navthar

    2012-07-01

    Full Text Available Hydroelectric power has become the most promising source in power sector to sustain the growth of any nation. In any hydroelectric power plant, hydraulic turbine plays a vital role which affects the overall performance of the plant and if utilized at suboptimal level, may lead to the loss of useful head. So, it becomes vital to predict the behavior of hydro-turbine under actual working conditions. Experimental approach of predicting the performance of hydro turbine is costly and time consuming compared to CFD approach. CFD has emerged out as a powerful tool for predicting the performance of mechanical bodies subjected to dynamic flow conditions. There are ample of evidences where analysts at various levels have taken the advantage of this tool to solve so many problems related to performance analysis. Along with it, simulation technique is key feature. The aim of this paper is to analyze the turbine for mechanical failure along with predicting its performance under actual operating condition by using CFD which is generally constrained by using a prototype. With the technique of simulation we can not only get the values of performance parameters but also the visualization of concentration and distribution of various parameters like pressure, velocity, stress at various locations where we may get versed with critical zones where the failure is supposed to occur.

  16. Progress in application of CFD techniques

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Computational Fluid Dynamics (CFD) is an important branch of fluid mechanics, and will continue to play great roles on the design of aerospace vehicles, explora- tion of new concept vehicles and new aerodynamic technology. This paper will present the progress of CFD from point of view of engineering application in recent years at CARDC, including the software integration, grid technique, speeding up of convergence, unsteady fluid computation,etc., and also give some engineering application examples of CFD at CARDC.

  17. Opstilling af ventilationsarmaturer i CFD-beregninger

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    2009-01-01

    Opstilling af armaturer i CFD-beregninger er et område, hvor ventilationsbranchen skal tilføre CFD-metoderne en specialviden, som ikke på forhånd er indlagt i programmerne. I artiklen bringes nogle eksempler på specificering af en indblæsningsåbning......Opstilling af armaturer i CFD-beregninger er et område, hvor ventilationsbranchen skal tilføre CFD-metoderne en specialviden, som ikke på forhånd er indlagt i programmerne. I artiklen bringes nogle eksempler på specificering af en indblæsningsåbning...

  18. CFD lends the government a hand

    Science.gov (United States)

    Lekoudis, Spiro; Singleton, Robert E.; Mehta, Unmeel B.

    1992-02-01

    The present survey of important and novel CFD applications being developed and implemented by U.S. Government contractors gives attention to naval vessel flow-modeling, Army ballistic and rotary wing aerodynamics, and NASA hypersonic vehicle related applications of CFD. CFD-generated knowledge of numerical algorithms, fluid motion, and supercomputer use is being incorporated into such additional areas as computational electromagnetics and acoustics. Attention is presently given to CFD methods' development status in such fields as submarine boundary layers, hypersonic kinetic energy projectile shock structures, helicopter main rotor tip flows, and National Aerospace Plane aerothermodynamics.

  19. Dicty_cDB: CFD732 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFD732 (Link to dictyBase) - - - Contig-U16560-1 CFD732F (Link to Original site) CFD...732F 113 - - - - - - Show CFD732 Library CF (Link to library) Clone ID CFD732 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/CF/CFD7-B/CFD732Q.Seq.d/ Representative seq. ID CFD73...2F (Link to Original site) Representative DNA sequence >CFD732 (CFD732Q) /CSM/CF/CFD7-B/CFD732Q.Seq.d/ ATTTT...clear 8.0 %: plasma membrane 8.0 %: endoplasmic reticulum 4.0 %: vesicles of secretory system 4.0 %: peroxis

  20. Generación eléctrica a partir de biomasa en una destilería diversificada

    Directory of Open Access Journals (Sweden)

    Pedro A. Rodríguez

    2007-01-01

    Full Text Available La instalación de una destilería de etanol diversificada, como una vía de generación de energía renovable integrada a la producción de alimentos, muestra relevantes ventajas en comparación con las destilerías tradicionales. En particular, para el caso de una planta de producción de etanol de este tipo, de 1200 hL/d, la generación de electricidad, con la biomasa que esta industria genera, alcanza el valor de 15,92 MW de potencia eléctrica excedente para el Sistema Electroenergético Nacional. Constituye un polo de desarrollo económico, social y estratégico, atendiendo al concepto de autosustentación dado por el Protocolo de Kyoto. El concepto de diversificación alcanza a todo el sector productivo. En las destilerías tradicionales la diversificación es incipiente. La biomasa constituye una de las principales fuentes de generación de energía limpia y barata, pasando de ser un subproducto, a un eslabón fundamental del proceso productivo.

  1. Reserva de carbono en biomasa forestal y suelos minerales en el Parque Nacional Malinche (México

    Directory of Open Access Journals (Sweden)

    María Eugenia Valdez Pérez

    2016-01-01

    Full Text Available Las áreas naturales protegidas representan una de las estrategias para la mitigación del cambio climático. El objetivo de esta investigación consistió en estimar el contenido de carbono en biomasa forestal en suelos minerales y calcular las pérdidas de carbono por cambios de uso del suelo en el Parque Nacional Malinche (PNM. La superficie de bosque del PNM es de 17.496,34 ha y almacena 1.544.377,66 mg en bosque y 4.148.985,97 mg en suelos. Para estimar el contenido de biomasa forestal se aplicaron ecuaciones alométricas y se trabajó con la cartografía del Instituto Nacional de Estadística y Geografía (INEGI en el análisis espacio-temporal de los cambios de uso de suelo. Para el carbono en suelos se aplicaron los valores del Panel Intergubernamental de Cambio Climático (IPCC.

  2. Visual Environments for CFD Research

    Science.gov (United States)

    Watson, Val; George, Michael W. (Technical Monitor)

    1994-01-01

    This viewgraph presentation gives an overview of the visual environments for computational fluid dynamics (CFD) research. It includes details on critical needs from the future computer environment, features needed to attain this environment, prospects for changes in and the impact of the visualization revolution on the human-computer interface, human processing capabilities, limits of personal environment and the extension of that environment with computers. Information is given on the need for more 'visual' thinking (including instances of visual thinking), an evaluation of the alternate approaches for and levels of interactive computer graphics, a visual analysis of computational fluid dynamics, and an analysis of visualization software.

  3. Estimación de biomasa residual mediante imágenes de satélite y trabajo de campo: Modelización del potencial energético de los bosques turolenses

    OpenAIRE

    García Martín, Alberto; Riva Fernández, Juan de la; Royo Herrer, Francisco Javier

    2010-01-01

    La utilización de biomasa residual forestal como recurso energético está por debajo de los objetivos fijados en materia de energías renovables dada la inexistencia de una metodología para evaluar la cantidad de residuos en una región. Esta investigación desarrolla una metodología para estimar esta biomasa a escala regional a partir del uso de teledetección y SIG. Para ello, se calcula la biomasa residual (tons/ha) en las parcelas del Segundo Inventario Forestal Nacional de la provincia de Ter...

  4. Empleo de la relación residuo producto para la estimación de biomasa cañera potencial. Caso de estudio

    Directory of Open Access Journals (Sweden)

    Lizet Rodríguez-Machín

    2014-01-01

    Full Text Available El panorama energético de la biomasa va tomando un mayor auge ante el vaticinado agotamiento de los combustibles fósiles, el impacto ambiental que representa y la seguridad energética asociada. El presente trabajo se desarrolla en la Unidad Empresarial de Base (UEB Héctor Rodríguez. Esta unidad emplea el bagazo obtenido en el proceso industrial de producción de azúcar para la generación de calor y de electricidad sin estimar adecuadamente su potencial. El propósito de esta investigación es aplicar las ecuaciones matemáticas para la estimación de la biomasa herbácea potencial al caso de la biomasa cañera (bagazo y conocer su disponibilidad con fines energéticos. Se aplicó el método de evaluación con relación residuo producto (RRP, el valor calculado está dentro del rango de los reportados en la literatura, pero fue preciso emplear el RRP calculado para el país por ser este más representativo que el calculado para la UEB. Se estimó que la biomasa potencial en central azucarero entre 2007 y 2012 fue de 98 856 t de bagazo. El potencial bruto máximo fue de 3 222 MW-h/día, lo cual permite establecer el límite superior a alcanzar en cuanto a potencial de biomasa se refiere en el proceso industrial pero no tiene en cuenta la totalidad de la caña producida en el proceso agrícola.

  5. Variación anual de la biomasa de Nymphoides fallax Ornduff (Menyanthaceae en la Laguna de Tecocomulco, Hidalgo, México

    Directory of Open Access Journals (Sweden)

    Agustin Quiroz-Flores

    2015-07-01

    Full Text Available Durante un ciclo anual se cuantificó la variación en la estratifi cación vertical de la biomasa deNymphoides fallaxy se analizaron las variables físicas y químicas del agua y sedimentos de la laguna de Tecocomulco, Hidalgo. La producción anual neta de N. fallax fue de 3 070.1 g PS m2. En el mes de junio la biomasa alcanzó su máximo (958.4 g PS m2 . La contribución de biomasa foliar de N. fallax a la proporción total de biomasa representa el 10%, la de peciolos alcanza el 40% y la contribución de biomasa subterránea equivale en ocasiones a más del 50%. El nivel de fósforo en los sedimentos se encuentra por arriba de la cantidad necesaria para sostener la producción vegetal (= 0.04%. Por los resultados obtenidos en este estudio, se puede señalar que en aquellas zonas ribereñas de la laguna en donde los agricultores han construido bordos, se propicia que durante la época de lluvias la columna de agua cambie bruscamente sus dimensiones pasando de 10 cm hasta alcanzar los 75 cm de profundidad y se eleven los niveles de fósforo en agua y sedimentos, lo que a su vez induce queNymphoides fallaxse vea estresada, y en un caso extremo, temporalmente sea sustituida por aquellas especies mejor adaptadas a las nuevas condiciones físicas y químicas del medio.

  6. Influencia de la aplicación de vinaza en actividad y biomasa microbiana en un Entic Dystropept y un Fluventic haplustoll del Valle del Cauca, Colombia

    Directory of Open Access Journals (Sweden)

    Sandra Patricia Montenegro Gómez

    2009-01-01

    Full Text Available Con la aplicación de vinaza, residuo de la producción de alcohol carburante a partir de la caña de azúcar, se evaluó el efecto sobre la actividad y biomasa microbiana del suelo y el suministro de K+ al cultivo de maíz dulce (Zea Mays en un Entic Dystropept y un Fluventic Haplustoll del Valle del Cauca, Colombia. Se utilizó un diseño completamente al azar con cuatro tratamientos y cinco repeticiones: T1 (100% requerimiento de K+ con KCl, T2 (100% requerimiento de K+ con vinaza, T3 (50% requerimiento de K+ con KCl +50% con vinaza y T4 (25% requerimiento de K+ con KCl +75% con vinaza. Se estimó biomasa microbiana por el método de fumigación-extracción. Se realizó análisis de varianza, prueba de comparación de medias, regresiones y correlaciones (SAS. Se presentaron diferencias significativas en la actividad y biomasa microbiana por época de muestreo y entre los diferentes muestreos; al final del cultivo el Entic Dystropept presentó el contenido más alto de biomasa microbiana-C en el T2, mientras que en el Fluventic Haplustoll fue en el T1. El menor qCO2 fue para el T2 del Entic Distropept y T1 del Fluventic Haplustoll, estos tratamientos presentaron mayor acumulación de biomasa en cada suelo respectivamente T2 (30 450 kg ha-1 y T1 (21 015.6 kg ha-1.

  7. Factores del manejo para estabilizar la producción de biomasa con leguminosas en el trópico

    Directory of Open Access Journals (Sweden)

    T. E. Ruiz

    2006-01-01

    Full Text Available Este material tiene como objetivo abundar acerca de aquellos factores del manejo que conduzcan a estabilizar la producción de biomasa en sistemas ganaderos en el trópico. Es obvio que los sistemas mejorados y bien manejados de pasturas de gramíneas y leguminosas, en cualquiera de sus alternativas, son opciones para lograr la sostenibilidad. Una concepción más amplia y profunda es la relativa a los estudios de pasturas mixtas; éstos, deben tener un enfoque más biológico por lo que, además de considerar el ambiente en el cual se desarrollan y crecen, hay que incluir la forma en que los componentes vegetales se manifiestan en las especies implicadas del agroecosistema. Aquí no podemos olvidar el efecto del animal. Los problemas asociados con la persistencia se reconocen cada vez más como una preocupación real. Los diversos factores que controlan la permanencia de las especies forrajeras se agrupan en aquellos que pueden ser manejados y controlados por el productor, así como en los que éste no puede intervenir. Es por ello que las producciones animales y de otro tipo, derivados de estos sistemas, varían positivamente en el tiempo, en la medida en que se va consolidando la relación suelo /planta /animal. De esta correspondencia no puede quedar excluido el papel interactuante y modificador del hombre con los elementos antes señalados. La producción de biomasa es una actividad multidisciplinaria; de ahí que el éxito de su funcionamiento esté condicionado al conocimiento de las interacciones entre sus componentes, así como entre éstos y el medio ambiente, lo cual permitirá la generación de estrategias de manejo acordes con la ecología que conduzcan a mejorar la productividad y la sostenibilidad del agroecosistema. Por tanto, la producción de biomasa constituye un elemento determinante en el éxito y la eficiencia de los sistemas con leguminosas.

  8. Revisión sobre la corrosión de tubos sobrecalentadores en plantas de biomasa

    Directory of Open Access Journals (Sweden)

    Berlanga-Labari, C.

    2006-08-01

    Full Text Available The design of new biomass-fired power plants with increased steam temperature raises concerns of high-temperature corrosion. The high potassium and chlorine contents in many biomasses, specially in wheat straw, are potentially harmful elements with regard to corrosion. Chlorine may cause accelerated corrosion resulting in increased oxidation, metal wastage, internal attack, void formations, and loose non-adherent scales. The most severe corrosion problems in biomass-fired systems are expected to occur due to Cl-rich deposits formed on superheater tubes. In the first part of this revision the corrosion mechanism proposed are described in function of the conditions and compounds involved. The second part is focused on the behaviour of the materials tested so far in the boiler and in the laboratory. First the traditional commercial alloys are studied and secondly the new alloys and the coatings

    En el diseño de plantas de biomasa es muy importante tener en cuenta la temperatura del vapor para no tener problemas de corrosión. Esto, es debido al alto contenido de potasio y cloro que tienen la mayoría de los biocombustibles y, en especial, la paja de cereal. El objetivo de esta revisión es condensar el conocimiento actual sobre la corrosión de los sobrecalentadores a altas temperaturas provocada por compuestos clorados en plantas de biomasa. El cloro puede causar corrosión acelerada debido a la pérdida de metal del sobrecalentador, ataque interno y formación de capas de óxidos no adherentes. Los problemas de corrosión más severos en una caldera de biomasa se producen en los depósitos formados sobre los tubos sobrecalentadores. En la primera parte de esta revisión, se describen los mecanismos de corrosión propuestos en función de las condiciones de trabajo predominantes en la caldera. La segunda parte, se centra en revisar los estudios realizados para comprobar el comportamiento de los materiales mediante ensayos realizados en la

  9. Gallinaza: Un residual avícola como fuente alternativa de nutrientes para producción de biomasa microalgal

    Directory of Open Access Journals (Sweden)

    Rosales Loaiza Nestor Luis

    2007-07-01

    Full Text Available La gallinaza puede ser usada como una fuente alternativa de nutrientes para el cultivo de microalgas, proveyendo de biomasa microalgal utilizable como producto final. El objetivo de este trabajo fue evaluar el efecto de la fracción soluble de gallinaza (FSG a tres diferentes concentraciones (6, 18 y 36% sobre el crecimiento, la producción de pigmentos y proteínas de la microalga marina Chroomonas sp. y de la microalga de agua dulce Chlorella sorokiniana. La FSG no biodegradada mostró un efecto letal sobre el crecimiento de ambas microalgas. La FSG tratada aeróbicamente mejoró el crecimiento de Chroomonas sp. a 18% con 131,37 ±13,66 x106 cel mL-1, y a 36% para C. sorokiniana de 228,64 ±4,90 x106 cel mL-1 (p

  10. CFD for Better Understanding of Wind Tunnel Tests

    OpenAIRE

    Qin, N.

    2003-01-01

    In this paper, we discuss how CFD may be used for better understanding of wind tunnel tests. Three examples are used to illustrate the potential use of CFD to help the understanding of phenomena observed in the wind tunnel tests, to extend/derive simple aerodynamic criteria based on CFD, and to use CFD to improve the accuracy of wind tunnel measurements.

  11. CFD Analysis of Centrifugal Pump: A Review

    Directory of Open Access Journals (Sweden)

    Narayan P. Jaiswal

    2014-05-01

    Full Text Available The main objective of this work is to understand role of the computational fluid dynamics (CFD technique in analyzing and predicting the performance of centrifugal pump. Computational Fluid Dynamics (CFD is the present day state-of-art technique for fluid flow analysis. The critical review of CFD analysis of CFD analysis of centrifugal pump along with future scope for further improvement is presented in this paper. Different solver like ANSYS-CFX, FLUENT etc can be used for simulations. Shear stress transport model has been found appropriate as turbulence model. Study of pressure contours, velocity contours, flow streamlines etc can be studied by CFD techniques. Unsteady Reynolds Averaged Navier Stokes (URANS equations are solved by solver to get flow simulation results inside centrifugal pump. CFD results has to be validated with testing results or with performance characteristics curves. Performance prediction at design and off-design conditions, parametric study, cavitation analysis, diffuser pump analysis, performance of pump running in turbine mode etc. are possible with CFD simulation techniques.

  12. CFD for wind and tidal offshore turbines

    CERN Document Server

    Montlaur, Adeline

    2015-01-01

    The book encompasses novel CFD techniques to compute offshore wind and tidal applications. Computational fluid dynamics (CFD) techniques are regarded as the main design tool to explore the new engineering challenges presented by offshore wind and tidal turbines for energy generation. The difficulty and costs of undertaking experimental tests in offshore environments have increased the interest in the field of CFD which is used to design appropriate turbines and blades, understand fluid flow physical phenomena associated with offshore environments, predict power production or characterise offshore environments, amongst other topics.

  13. Improved interpretation and validation of CFD predictions

    DEFF Research Database (Denmark)

    Popiolek, Z.; Melikov, Arsen Krikor

    2004-01-01

    The mean velocity in rooms predicted by CFD simulations based on RANS equations differs from the mean (in time) magnitude of the velocity, i.e. the mean speed, in rooms measured by low velocity thermal anemometers with omnidirectional sensor. This discrepancy results in incorrect thermal comfort...... assessment by the CFD predictions as well as incorrect validation of the predicted velocity field. In this paper the discrepancies are discussed and identified, and a method for estimating of the mean speed based on the CFD predictions of mean velocity and kinetic turbulence energy is suggested. The method...

  14. Progress in application of CFD techniques

    Institute of Scientific and Technical Information of China (English)

    CHEN ZuoBin; JIANG Xiong; ZHOU Zhu; XIAO HanShan; HUANG Yong; MOU Bin; XIAO ZhongYun; LIU Gang; WANG YunTao

    2008-01-01

    Computational Fluid Dynamics (CFD) is an important branch of fluid mechanics,and will continue to play great roles on the design of aerospace vehicles,exploration of new concept vehicles and new aerodynamic technology.This paper will present the progress of CFD from point of view of engineering application in recent years at CARDC,including the software integration,grid technique,speeding up of convergence,unsteady fluid computation,etc.,and also give some engineering application examples of CFD at CARDC.

  15. OBTENCIÓN DE UNA BEBIDA FERMENTADA A PARTIR DE SUERO DE QUESO UTILIZANDO CÉLULAS INMOVILIZADAS DE KLUYVEROMYCES MARXIANUS

    Directory of Open Access Journals (Sweden)

    Rocío Cóndor G.

    2014-06-01

    Full Text Available El presente estudio tuvo como objetivo principal optimizar la tecnología de producción de una bebida fermentada de suero de queso, utilizando Kluyveromyces marxianus e inmovilización de células. En el biorreactor de lecho empacado, se obtuvo el mayor rendimiento (11,46±0,81 oGL con un flujo de 140-150 mL. h-1, una biomasa inmovilizada de 10% (v/v, una relación de columna de 1:12 (diámetro: longitud, tamaño de perlas de 3 mm de diámetro, adición de metabisulfito de sodio (100 pg. mL-1 y células inmovilizadas con 2% (p/v de alginato. Luego de optimizado todos los parámetros de fermentación en el biorreactor, la bebida alcohólica fue sometida a inactivación a 70 oC por 5 minutos (tratamiento térmico y clarificación con tierra de diatomeas (11 kg. M-2. Finalmente, la bebida alcohólica fue evaluada en almacenamiento por 6 meses, durante este período se le hicieron evaluaciones fisicoquímicas, microbiológicas y sensoriales. Se determinó por Escala Hedónica y Ranking que la bebida alcohólica de suero tiene aceptabilidad.

  16. CFD Studies on Biomass Thermochemical Conversion

    Directory of Open Access Journals (Sweden)

    Lifeng Yan

    2008-06-01

    Full Text Available Thermochemical conversion of biomass offers an efficient and economically process to provide gaseous, liquid and solid fuels and prepare chemicals derived from biomass. Computational fluid dynamic (CFD modeling applications on biomass thermochemical processes help to optimize the design and operation of thermochemical reactors. Recent progression in numerical techniques and computing efficacy has advanced CFD as a widely used approach to provide efficient design solutions in industry. This paper introduces the fundamentals involved in developing a CFD solution. Mathematical equations governing the fluid flow, heat and mass transfer and chemical reactions in thermochemical systems are described and sub-models for individual processes are presented. It provides a review of various applications of CFD in the biomass thermochemical process field.

  17. Liquid rocket propulsion impeller CFD modeling

    Science.gov (United States)

    Ratcliff, Mark L.; Athavale, Mahesh M.; Thomas, Matthew E.; Williams, Robert W.

    1993-01-01

    Steady-state impeller geometric modeling and typical Navier-Stokes CFD algorithm analysis procedures are assessed using two benchmark quality impeller data sets. Two geometric modeling and grid generation software packages, ICEM-CFD and PATRAN, are considered. Results show that a significant advantage of PATRAN's open-ended architecture is the potential interaction between CFD and structural/thermal analysts inside the mechanical computer-aided engineering environment. However the time required to construct the inducer grid would be unacceptable in a design and engineering environment. The ICEM-CFD package is considered to be more appropriate for structural grid generation but lacks the mature link to structural/thermal analysis arena as compared to PATRAN.

  18. ARC Code TI: CFD Utility Software Library

    Data.gov (United States)

    National Aeronautics and Space Administration — The CFD Utility Software Library consists of nearly 30 libraries of Fortran 90 and 77 subroutines and almost 100 applications built on those libraries. Many of the...

  19. CFD simulation of neutral ABL flows

    OpenAIRE

    Zhang, Xiaodong

    2009-01-01

    This work is to evaluate the CFD prediction of Atmospheric Boundary Layer flow field over different terrains employing Fluent 6.3 software. How accurate the simulation could achieve depend on following aspects: viscous model, wall functions, agreement of CFD model with inlet wind velocity profile and top boundary condition. Fluent employ wall function roughness modifications based on data from experiments with sand grain roughened pipes and channels, describe wall adjacent zone with Roughness...

  20. Análisis Exergético de la Gasificación de Biomasa Exergy Analysis of Biomass Gasification

    OpenAIRE

    Jorge M Mendoza; Antonio J Bula; Rafael D Gómez; Lesmes A. Corredor

    2012-01-01

    El objetivo de este estudio fue realizar el análisis exergético de la gasificación de biomasa residual con la finalidad de obtener energía útil. Se desarrolló un modelo para la gasificación de biomasa basado en el equilibrio químico de las reacciones. Este modelo permite predecir la evolución de la composición del gas de síntesis en función de la temperatura, las presiones y la composición elemental de los residuos del proceso de extracción de aceite de palma y orujo de lavado de uva (hidroge...

  1. Variabilidad del estado trófico y la biomasa del fitoplancton de Bahía Concepción, Golfo de California (1997-1999)

    OpenAIRE

    López Cortés, David J.; Ismael Gárate Lizárraga; José J. Bustillos Guzmán; Rosalba Alonso Rodríguez; Iban Murillo Murillo

    2003-01-01

    Con el propósito de determinar la variación de la biomasa del fitoplancton (clorofila a) y el estado trófico de Bahía Concepción ubicada en la parte central oeste del Golfo de California, se realizó un estudio hidro-biológico durante el período de 1997 a 1999. Se determinó la temperatura, la concentración del oxígeno disuelto y de nutrientes inorgánicos (nitrato, nitrito, fosfato y silicato), y la biomasa fitoplanctónica (clorofila a). Las condiciones hidrográficas muestran un período de mezc...

  2. Posibilidades técnicas del uso de biomasa no alimentaria para la obtención de energía en España

    OpenAIRE

    Fuertes Sánchez, Alicia

    2009-01-01

    gías renovables dentro de la producción de energía primaria aumentará en los próximos años. La biomasa es una fuente de energía renovable, esta engloba un grupo de productos energéticos y materias primas que se originan a partir de materia orgánica formada por vía biológica. Dentro del consumo de energía primaria en Europa, en el año 2003 las energías renovables representaron un 6% del total según datos de Eurostat. Dentro de este 6%, un 4% corresponde a biomasa seguida de la energía hidráuli...

  3. CFD simulation of coaxial injectors

    Science.gov (United States)

    Landrum, D. Brian

    1993-01-01

    The development of improved performance models for the Space Shuttle Main Engine (SSME) is an important, ongoing program at NASA MSFC. These models allow prediction of overall system performance, as well as analysis of run-time anomalies which might adversely affect engine performance or safety. Due to the complexity of the flow fields associated with the SSME, NASA has increasingly turned to Computational Fluid Dynamics (CFD) techniques as modeling tools. An important component of the SSME system is the fuel preburner, which consists of a cylindrical chamber with a plate containing 264 coaxial injector elements at one end. A fuel rich mixture of gaseous hydrogen and liquid oxygen is injected and combusted in the chamber. This process preheats the hydrogen fuel before it enters the main combustion chamber, powers the hydrogen turbo-pump, and provides a heat dump for nozzle cooling. Issues of interest include the temperature and pressure fields at the turbine inlet and the thermal compatibility between the preburner chamber and injector plate. Performance anomalies can occur due to incomplete combustion, blocked injector ports, etc. The performance model should include the capability to simulate the effects of these anomalies. The current approach to the numerical simulation of the SSME fuel preburner flow field is to use a global model based on the MSFC sponsored FNDS code. This code does not have the capabilities of modeling several aspects of the problem such as detailed modeling of the coaxial injectors. Therefore, an effort has been initiated to develop a detailed simulation of the preburner coaxial injectors and provide gas phase boundary conditions just downstream of the injector face as input to the FDNS code. This simulation should include three-dimensional geometric effects such as proximity of injectors to baffles and chamber walls and interaction between injectors. This report describes an investigation into the numerical simulation of GH2/LOX coaxial

  4. CFD Simulation On CFBC Boiler

    Directory of Open Access Journals (Sweden)

    Amol S. Kinkar

    2015-02-01

    Full Text Available Abstract Heavy industrialization amp modernization of society demands in increasing of power cause to research amp develop new technology amp efficient utilization of existing power units. Variety of sources are available for power generation such as conventional sources like thermal hydro nuclear and renewable sources like wind tidal biomass geothermal amp solar. Out of these most common amp economical way for producing the power is by thermal power stations. Various industrial boilers plays an important role to complete the power generation cycle such as CFBC Circulating Fluidized Bed Combustion FBC Fluidized Bed Combustion AFBC Atmospheric Fluidized Bed Combustion Boiler CO Boiler RG amp WHR Boiler Waster heat recovery Boiler. This paper is intended to comprehensively give an account of knowledge related to refractory amp its failure in CFBC boiler with due effect of flue gas flow during operation on refractory by using latest technology of CAD Computer aided Design amp CAE Computer aided Engineering. By conceptual application of these technology the full scale model is able to analyze in regards the flow of flue gas amp bed material flow inside the CFBC loop via CFD Computational Fluid Dynamics software. The results obtained are helpful to understand the impact of gas amp particles on refractory in different areas amp also helped to choose suitable refractory material in different regions.

  5. ON NUMERICAL TECHNIQUES IN CFD

    Institute of Scientific and Technical Information of China (English)

    Zhuang Fenggan

    2000-01-01

    Numerical techniques play an important role in CFD. Some of them are reviewed in this paper. The necessity of using high order difference scheme is demonstrated for the study of high Reynolds number viscous flow. Physical guide lines are provided for the construction of these high order schemes. To avoid unduly ad hoc treatment in the boundary region the use of compact scheme is recommended because it has a small stencil size compared with the traditional finite difference scheme. Besides preliminary Fourier analysis shows the compact scheme can also yield better space resolution which makes it more suitable to study flow with multiscales e.g. turbulence. Other approaches such as perturbation method and finite spectral method are also emphasized. Typical numerical simulations were carried out. The first deals with Euler equations to show its capabilities to capture flow discontinuity.The second deals with Navier-Stokes equations studying the evolution of a mixing layer, the pertinent structures at different times are shown. Asymmetric break down occurs and also the appearance of small vortices.

  6. Bioadsorción de Cadmio (II en Solución Acuosa por Biomasas Fúngicas Biosorption of Cadmium (II in Aqueous Solutions by Fungal Biomass

    Directory of Open Access Journals (Sweden)

    Ismael Acosta

    2007-01-01

    Full Text Available Se determinó la bioadsorción de Cadmio (II en solución por la biomasa celular de quince hongos, por el método colorimétrico de la ditizona. La biomasa de Mucor rouxii IM-80 fue más eficiente en la remoción de Cadmio (II en solución (8.2 mg/g seguida de M. rouxii mutante (7.1 mg/g, A. flavus I (5.9 mg/g y Helminthosporium sp (5.4 mg/g. Para la biomasa de M. rouxii-IM-80, la mayor bioadsorción fue a pH= 5.0-6.0, a 28ºC durante 40 horas con 1.0 mg/200 mL de concentración inicial de Cadmio (II y 80 mg/200 mL de biomasa celular. Se concluye que algunas biomasas fúngicas remueven eficientemente Cadmio (II en solución y pueden utilizarse para descontaminar nichos acuáticos contaminados con este metalThe biosorption of dissolved Cadmium (II using cellular biomass of 15 fungi, using a dithizone colorimetric method, was determined. The Mucor rouxii IM-80 biomass was more efficient in removing Cadmium (II from solution (8.2 mg/g, followed by the M. rouxii mutant (7.1 mg/g, Aspergillus flavus I (5.9 mg/g and Helminthosporium sp (5.4 mg/g biomasses. The highest biosorption for M. rouxii IM-80 was at pH 5.0-6.0, at 28ºC for 40 h employing 1.0 mg/200mL of Cadmium (II as initial concentration, and 80 mg/200 mL of fungal biomass. It was concluded that some fungal biomass efficiently removed Cadmium (II from solution and could be used for decontamination of aquatic habitats polluted with this metal

  7. Influencia de la aplicación de vinaza en actividad y biomasa microbiana en un Entic Dystropept y un Fluventic haplustoll del Valle del Cauca, Colombia

    Directory of Open Access Journals (Sweden)

    Bonilla Correa Carmen Rosa

    2009-03-01

    Full Text Available Con la aplicación de vinaza, residuo de la producción de alcohol carburante a partir de la caña de azúcar, se evaluó el efecto sobre la actividad y biomasa microbiana del suelo y el suministro de K+ al cultivo de maíz dulce (Zea Mays en un Entic Dystropept y un Fluventic Haplustoll del Valle del Cauca, Colombia. Se utilizó un diseño completamente al azar con cuatro tratamientos y cinco repeticiones: T1 (100% requerimiento de K+ con KCl, T2 (100% requerimiento de K+ con vinaza, T3 (50% requerimiento de K+ con KCl +50% con vinaza y T4 (25% requerimiento de K+ con KCl +75% con vinaza. Se estimó biomasa microbiana por el método de fumigación-extracción. Se realizó análisis de varianza, prueba de comparación de medias, regresiones y correlaciones (SAS. Se presentaron diferencias significativas en la actividad y biomasa microbiana por época de muestreo y entre los diferentes muestreos; al final del cultivo el Entic Dystropept presentó el contenido más alto de biomasa microbiana-C en el T2, mientras que en el Fluventic Haplustoll fue en el T1. El menor qCO2 fue para el T2 del Entic Distropept y T1 del Fluventic Haplustoll, estos tratamientos presentaron mayor acumulación de biomasa en cada suelo respectivamente T2 (30 450 kg ha-1 y T1 (21 015.6 kg ha-1.

  8. TANK48 CFD MODELING ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.

    2011-05-17

    The process of recovering the waste in storage tanks at the Savannah River Site (SRS) typically requires mixing the contents of the tank to ensure uniformity of the discharge stream. Mixing is accomplished with one to four dual-nozzle slurry pumps located within the tank liquid. For the work, a Tank 48 simulation model with a maximum of four slurry pumps in operation has been developed to estimate flow patterns for efficient solid mixing. The modeling calculations were performed by using two modeling approaches. One approach is a single-phase Computational Fluid Dynamics (CFD) model to evaluate the flow patterns and qualitative mixing behaviors for a range of different modeling conditions since the model was previously benchmarked against the test results. The other is a two-phase CFD model to estimate solid concentrations in a quantitative way by solving the Eulerian governing equations for the continuous fluid and discrete solid phases over the entire fluid domain of Tank 48. The two-phase results should be considered as the preliminary scoping calculations since the model was not validated against the test results yet. A series of sensitivity calculations for different numbers of pumps and operating conditions has been performed to provide operational guidance for solids suspension and mixing in the tank. In the analysis, the pump was assumed to be stationary. Major solid obstructions including the pump housing, the pump columns, and the 82 inch central support column were included. The steady state and three-dimensional analyses with a two-equation turbulence model were performed with FLUENT{trademark} for the single-phase approach and CFX for the two-phase approach. Recommended operational guidance was developed assuming that local fluid velocity can be used as a measure of sludge suspension and spatial mixing under single-phase tank model. For quantitative analysis, a two-phase fluid-solid model was developed for the same modeling conditions as the single

  9. Gasificaton Transport: A Multiphase CFD Approach & Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Dimitri Gidaspow; Veeraya Jiradilok; Mayank Kashyap; Benjapon Chalermsinsuwan

    2009-02-14

    The objective of this project was to develop predictive theories for the dispersion and mass transfer coefficients and to measure them in the turbulent fluidization regime, using existing facilities. A second objective was to use our multiphase CFD tools to suggest optimized gasifier designs consistent with aims of Future Gen. We have shown that the kinetic theory based CFD codes correctly compute: (1) Dispersion coefficients; and (2) Mass transfer coefficients. Hence, the kinetic theory based CFD codes can be used for fluidized bed reactor design without any such inputs. We have also suggested a new energy efficient method of gasifying coal and producing electricity using a molten carbonate fuel cell. The principal product of this new scheme is carbon dioxide which can be converted into useful products such as marble, as is done very slowly in nature. We believe this scheme is a lot better than the canceled FutureGen, since the carbon dioxide is safely sequestered.

  10. Coarse Grid CFD for underresolved simulation

    Science.gov (United States)

    Class, Andreas G.; Viellieber, Mathias O.; Himmel, Steffen R.

    2010-11-01

    CFD simulation of the complete reactor core of a nuclear power plant requires exceedingly huge computational resources so that this crude power approach has not been pursued yet. The traditional approach is 1D subchannel analysis employing calibrated transport models. Coarse grid CFD is an attractive alternative technique based on strongly under-resolved CFD and the inviscid Euler equations. Obviously, using inviscid equations and coarse grids does not resolve all the physics requiring additional volumetric source terms modelling viscosity and other sub-grid effects. The source terms are implemented via correlations derived from fully resolved representative simulations which can be tabulated or computed on the fly. The technique is demonstrated for a Carnot diffusor and a wire-wrap fuel assembly [1]. [4pt] [1] Himmel, S.R. phd thesis, Stuttgart University, Germany 2009, http://bibliothek.fzk.de/zb/berichte/FZKA7468.pdf

  11. Asynchronous Parallelization of a CFD Solver

    Directory of Open Access Journals (Sweden)

    Daniel S. Abdi

    2015-01-01

    Full Text Available A Navier-Stokes equations solver is parallelized to run on a cluster of computers using the domain decomposition method. Two approaches of communication and computation are investigated, namely, synchronous and asynchronous methods. Asynchronous communication between subdomains is not commonly used in CFD codes; however, it has a potential to alleviate scaling bottlenecks incurred due to processors having to wait for each other at designated synchronization points. A common way to avoid this idle time is to overlap asynchronous communication with computation. For this to work, however, there must be something useful and independent a processor can do while waiting for messages to arrive. We investigate an alternative approach of computation, namely, conducting asynchronous iterations to improve local subdomain solution while communication is in progress. An in-house CFD code is parallelized using message passing interface (MPI, and scalability tests are conducted that suggest asynchronous iterations are a viable way of parallelizing CFD code.

  12. Efficient Turbulence Modeling for CFD Wake Simulations

    DEFF Research Database (Denmark)

    van der Laan, Paul

    Wind turbine wakes can cause 10-20% annual energy losses in wind farms, and wake turbulence can decrease the lifetime of wind turbine blades. One way of estimating these effects is the use of computational fluid dynamics (CFD) to simulate wind turbines wakes in the atmospheric boundary layer. Since...... wind farm, the simulated results cannot be compared directly with wind farm measurements that have a high uncertainty in the measured reference wind direction. When this uncertainty is used to post-process the CFD results, a fairer comparison with measurements is achieved....... this flow is in the high Reynolds number regime, it is mainly dictated by turbulence. As a result, the turbulence modeling in CFD dominates the wake characteristics, especially in Reynolds-averaged Navier-Stokes (RANS). The present work is dedicated to study and develop RANS-based turbulence models...

  13. CFD simulation of neutral ABL flows

    DEFF Research Database (Denmark)

    Zhang, Xiaodong

    and top boundary condition. Fluent employ wall function roughness modifications based on data from experiments with sand grain roughened pipes and channels, describe wall adjacent zone with Roughness Height (Ks) instead of Roughness Length (z0). In a CFD simulation of ABL flow, the mean wind velocity...... ABL and the measurements are best documented until now. Comparison with measured data shows that the CFD model can well predict the velocity field and relative turbulence kinetic energy field. Furthermore, a series of artificial complex terrains are designed, and some of the main simulation results...

  14. CFD Computations on Multi-GPU Configurations.

    Science.gov (United States)

    Menon, Sandeep; Perot, Blair

    2007-11-01

    Programmable graphics processors have shown favorable potential for use in practical CFD simulations -- often delivering a speed-up factor between 3 to 5 times over conventional CPUs. In recent times, most PCs are supplied with the option of installing multiple GPUs on a single motherboard, thereby providing the option of a parallel GPU configuration in a shared-memory paradigm. We demonstrate our implementation of an unstructured CFD solver using a set up which is configured to run two GPUs in parallel, and discuss its performance details.

  15. CFD simulations of the MEXICO rotor

    DEFF Research Database (Denmark)

    Bechmann, Andreas; Sørensen, Niels N.; Zahle, Frederik

    2011-01-01

    The wake behind a wind turbine model is investigated using Computational Fluid Dynamics (CFD), and results are compared with measurements. The turbine investigated is the three‐bladed test rotor (D = 4.5 m) used in the Model Experiments in Controlled Conditions (MEXICO) wind tunnel experiment....... During the MEXICO experiment, particle image velocimetry measurements of the induction upstream and downstream of the rotor were performed for different operating conditions, giving a unique dataset to verify theoretical models and CFD models. The present paper first describes the efforts in reproducing...

  16. The Brent Contract for Differences (CFD)

    International Nuclear Information System (INIS)

    The market for Brent Contracts-for-Differences (CFDs) emerged as early as 1988 but its significant development did not occur until 1992. By financial market standards, however, this span of life is fairly long. Yet the characteristics and role of this oil trading instrument have not been seriously studied. This study aims at filling a gap in research on the Brent market complex which includes spot trades, a 15-day forward and futures contracts, various derivatives and, finally, the less well documented CFD. Chapters 2 and 3 aim to describe and explain the characteristics of the CFD market, in particular the evolution in contract terms and the composition of participants. (UK)

  17. CFD Simulation of Annular Centrifugal Extractors

    Directory of Open Access Journals (Sweden)

    S. Vedantam

    2012-01-01

    Full Text Available Annular centrifugal extractors (ACE, also called annular centrifugal contactors offer several advantages over the other conventional process equipment such as low hold-up, high process throughput, low residence time, low solvent inventory and high turn down ratio. The equipment provides a very high value of mass transfer coefficient and interfacial area in the annular zone because of the high level of power consumption per unit volume and separation inside the rotor due to the high g of centrifugal field. For the development of rational and reliable design procedures, it is important to understand the flow patterns in the mixer and settler zones. Computational Fluid Dynamics (CFD has played a major role in the constant evolution and improvements of this device. During the past thirty years, a large number of investigators have undertaken CFD simulations. All these publications have been carefully and critically analyzed and a coherent picture of the present status has been presented in this review paper. Initially, review of the single phase studies in the annular region has been presented, followed by the separator region. In continuation, the two-phase CFD simulations involving liquid-liquid and gas-liquid flow in the annular as well as separator regions have been reviewed. Suggestions have been made for the future work for bridging the existing knowledge gaps. In particular, emphasis has been given to the application of CFD simulations for the design of this equipment.

  18. Perspective: Selected benchmarks from commercial CFD codes

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, C.J. [Southwest Research Inst., San Antonio, TX (United States). Computational Mechanics Section

    1995-06-01

    This paper summarizes the results of a series of five benchmark simulations which were completed using commercial Computational Fluid Dynamics (CFD) codes. These simulations were performed by the vendors themselves, and then reported by them in ASME`s CFD Triathlon Forum and CFD Biathlon Forum. The first group of benchmarks consisted of three laminar flow problems. These were the steady, two-dimensional flow over a backward-facing step, the low Reynolds number flow around a circular cylinder, and the unsteady three-dimensional flow in a shear-driven cubical cavity. The second group of benchmarks consisted of two turbulent flow problems. These were the two-dimensional flow around a square cylinder with periodic separated flow phenomena, and the stead, three-dimensional flow in a 180-degree square bend. All simulation results were evaluated against existing experimental data nd thereby satisfied item 10 of the Journal`s policy statement for numerical accuracy. The objective of this exercise was to provide the engineering and scientific community with a common reference point for the evaluation of commercial CFD codes.

  19. Modelling Complex Inlet Geometries in CFD

    DEFF Research Database (Denmark)

    Skovgaard, M.; Nielsen, Peter V.

    field. In order to apply CFD for this purpose it is essential to be able to model the inlet conditions precisely and effectively, in a way which is comprehensible to the manufacturer of inlet devices and in a way which can be coped with by the computer. In this paper a universal method is presented and...

  20. Numerical CFD Comparison of Lillgrund Employing RANS

    DEFF Research Database (Denmark)

    Simisiroglou, N.; Breton, S.-P.; Crasto, G.;

    2014-01-01

    The following article will validate the results obtained using the actuator disc method in the state of the art numerical Computational Fluid Dynamic (CFD) tool WindSim using on-site measurements from the offshore wind farm Lillgrund. WindSim solves the mass, momentum and energy conservation...

  1. Recent Efforts for Credible CFD Simulations in China

    Directory of Open Access Journals (Sweden)

    Li Li

    2011-01-01

    Full Text Available In this paper some recent efforts for credible computational fluid dynamics (CFD simulations in China are reviewed. The most important effort is that, following similar activities in the West such as ECARP and AIAA Drag Prediction Workshops, a series of workshops on credible CFD simulations had been initiated. These workshops were with ambitions to assess the status of CFD in China. Another major effort is an ongoing project to establish a software platform for studying the credibility of CFD solvers and performing credible CFD simulations. The platform, named WiseCFD, was designed to implement a seamless CFD process and to circumvent tedious repeating manual operations. It had also been a powerful job manager for CFD with capabilities to support plug and play (PnP solver integration as well as distributed or parallel computations. Some future work on WiseCFD was proposed, and also envisioned was how WiseCFD and the European QNET-CFD Knowledge Base can benefit mutually.

  2. Estimación de Iluminación en un Fotobiorreactor Productor de Biomasa a Partir de Microalgas

    Directory of Open Access Journals (Sweden)

    Carlos Francisco González Hernández

    2014-01-01

    Full Text Available En el presente trabajo se realizó el análisis de iluminación artificial para un fotobiorreactor productor de biomasa a partir de microalgas, el cual fue diseñado previamente con fines en aplicación para la producción de biocombustibles. En el análisis, se utilizó como herramienta la técnica de contornos o también conocida como método de superficie de respuesta, para lo cual se establecieron 132 puntos de intensidad luminosa distribuidos de forma simétrica a diferentes alturas del contenedor. Se realizaron dos bioensayos uno con la iluminación en la parte inferior del recipiente usando Diodos Emisores de Luz (LED’s, por sus siglas en inglés y el otro adicionando 3 lámparas fluorescentes más, situadas periféricamente a la mitad de la altura total del fotobiorreactor. Los resultados de las mediciones muestran una mejoría en el sistema de iluminac ión que favorece la reproducción continua de las microalgas, cuando se utilizó la combinación de luz emitida por LED’s y por lámparas fluorescentes. Esta combinación de sistemas de iluminación generó las condiciones para poder realizar las funciones metabólicas de las microalgas, quienes necesitan en promedio 2500 lx de forma homogénea.

  3. Estudio de la oxidación a elevada temperatura de ocho aleaciones en atmósferas de combustión de biomasa

    Directory of Open Access Journals (Sweden)

    Berlanga-Labari, C.

    2008-08-01

    Full Text Available The combustion of biomass, especially wheat straw, generates very corrosive media particularly near the superheater tubes. Chlorine is known to be the main corrosive agent in biomass-fired plants. This paper focuses on the study of the corrosivity of such environments composed of gases and ashes, at high temperature, on eight commercial alloys with different chromium and nickel contents. These have been: AISI 347 CG (1.4550, AISI 347 FG(1.4550, AISI 316LN (1.4910, ESSHETE 1250 (1.4982, AC 66 (1.4877, X20CrMoV12:1 (1.4922 and AISI 347 coated with Inconel 625 and Inconel 686. Corrosion tests in the boiler have been performed during 8.000 h and 15.000 h at temperatures between 500 °C y 550 °C in the biomass plant of Sangüesa (Navarra, Spain. Experimental results showed an unacceptable behaviour far the martensitic steel, acceptable far the austenitics and good far the inconels. The appearance of the corrosion attack was also investigated to obtain understanding of the corrosion mechanism. The corrosion mechanism by molten salts has been rejected. The active oxidation corrosion mechanism has been proposed as the most probable in order to interpretate the corrosion behaviour of these materials in these environments.

    La combustión de biomasa, especialmente de paja de cereal, genera un ambiente muy corrosivo, particularmente, cerca de los tubos sobrecalentadores. El cloro es el principal agente corrosivo en las plantas de biomasa. Este trabajo se centra en comprobar el comportamiento de ocho aleaciones comerciales en una ambiente de combustión de biomasa. Los materiales estudiados han sido las siguientes: AISI 347 CG (1.4550, AISI 347 FG (1.4550, AISI 316LN (1.4910, ESSHETE 1250 (1.4982, AC 66 (1.4877, X20CrMoV12:1 (1.4922 y AISI 347 recubiertos con Inconel 625 e Inconel 686. Los ensayos se han realizado en la caldera de la planta de biomasa de Sangüesa (Navarra, España durante 8.000 y 15.000 h a una temperatura de 500-550 °C. Los

  4. Cambio en el PSI y la RAS de un suelo y su influencia en la actividad biológica y la biomasa microbiana

    OpenAIRE

    Gasca Valderrama, Cesar Augusto

    2010-01-01

    Con el objetivo de evaluar los cambios en el PSI, la RAS y su influencia en la actividad y biomasa mircrobiana del suelo, se aplicaron diversos tratamientos con vinaza como enmienda procedente de la industria de alcohol carburante, sobre un suelo afectado por sodicidad con severas limitaciones en las condiciones físicas, químicas y biológicas. Se aplicó diseño en bloques completos al azar con cuatro tratamientos y tres repeticiones, y se evaluaron las propiedades del suelo: Actividad biológic...

  5. Estimación de biomasa fitoplanctónica, derivada de datos de satélite, frente a Baja California Sur

    OpenAIRE

    Saúl Álvarez Borrego; Eduardo Santamaría del Ángel; Iriana Leticia Zuria Jordan; Frank E. Müller Karger

    1995-01-01

    Se utilizaron todas las estimaciones disponibles de la concentración de pigmentos fotosintéticos derivadas de datos generados por el sensor Coastal Zone Color Scanner (CZCS) en el periodo 19781986, para interpretar las variaciones espaciales y temporales de la biomasa de fítoplancton, en un transecto de punta San Hipólito (27”N, ll4”30’0) a cabo Corrientes (20”3O’N, 105”30’0), frente al sur de Baja California, México. Las mayores concentraciones de pigmentos fotosintéticos se presentaron cerc...

  6. Cuantificación de biomasa y carbono en bosques nativos de Prosopis caldenia (Burkart) en la Pampa semiárida, Argentina.

    OpenAIRE

    Risio Allione, Lucía

    2012-01-01

    Los bosques del sur-oeste de la pampa Argentina están dominados por caldén (Prosopis caldenia). En la actualidad resta el 18 % de su superficie original. Existen iniciativas que reconocen a los bosques su rol de oferentes de servicios ambientales pero para alcanzar esta recompensa económica es necesario cuantificar la cantidad de carbono almacenado en ellos. En este trabajo se desarrolló un modelo de estimación de biomasa para caldén a partir de 38 árboles apeados y seccionados. Se ajustó un ...

  7. Análisis de la situación actual del aprovechamiento de la biomasa para producción de electricidad en España

    OpenAIRE

    Varela Antón, Daniel

    2013-01-01

    La actual situación de crisis mundial unido al aumento de precio de los combustibles tradicionales y los efectos sobre el clima que estos suponen, crean la necesidad en la sociedad moderna de encontrar nuevas fuentes de abastecimiento energético. En este proyecto se pretende dar a conocer las tecnologías actuales para la producción eléctrica mediante el empleo de la biomasa en sus diferentes formas, sin olvidar algunas otras aplicaciones como la generación térmica y la automoci...

  8. Uso de la biomasa como fuente de energía para el secado agroindustrial del café: estudio de caso

    OpenAIRE

    Luis Zamora González; Bienvenido Sarría López; Yusleidis Cisnero Reyna

    2005-01-01

    El trabajo trata sobre el análisis de siete variantes de calentamiento del aire que se emplea en el proceso de secado del café, teniendo en cuenta los aspectos térmicos, hidrodinámicos, energéticos, exergéticos y económicos, con la singularidad de que la biomasa se quema en un Horno de Capa Cónica Deslizante (HCCD). Se concluye que la variante número seis reúne las condiciones más atractivas para su utilización en el proceso de calentamiento del aire, utilizado en el secado del café,...

  9. Evaluación del cultivo de la dorada ( Brycon moorei sinuensis en jaulas flotantes utilizando cuatro alimentos concentrados.

    Directory of Open Access Journals (Sweden)

    Robinsón Rosado

    2003-12-01

    Full Text Available El presente estudio se inició el 30 de septiembre del2000 con el cultivo de Dorada (Brycon mooreisinuensis en jaulas flotantes en el reservorio de laGranja Piscícola Tamarindo (El Espinal, Colombia,utilizando cuatro alimentos concentrados durante 180días. Se determinó el crecimiento mediante laganancia en longitud, ganancia en peso, tasa decrecimiento específico, sobre-vivencia final, biomasatotal, factor de condición, factor de conversiónalimenticia. Se sembraron 816 juveniles con longitudpromedio de 17.8 cm y peso promedio de 78.9 g,divididos en cuatro tratamientos con densidad desiembra de 25 peces/cm3 y tres réplicas cada uno.Las dietas balanceadas (proteína bruta y la cantidadde energía (Kcal/Kg suministrada fueron: Tratamiento1: 20% y 2637; tratamiento 2: 32% y 3127;tratamiento 3: 28% y 2852; y tratamiento 4: 24% y2751, respectivamente. El diseño experimental fuecompletamente aleatorio y se aplicó la técnica deanálisis de varianza a los datos biométricos yparámetros físico-químicos. Como prueba designificancia se usó la prueba de Tukey-Kramer con95% de confiabilidad. El modelo matemático de VIONBERTALANFY y la transformación de FOR-WALFORDfueron válidos para el ajuste de las curvas decrecimiento en longitud, peso y la relación longitud– peso. Se puede afirmar que la Dorada consumiólas dietas de origen vegetal de igual manera que lasde origen animal, sin embargo la dieta del 28% deproteína bruta (tratamiento 3 muestra los mejoresresultados, sin diferencias significativas entretratamientos (p > 0.05. De acuerdo con la literaturacitada no hay investigaciones que muestren losrequerimientos nutricionales óptimos para laalimentación de esta especie. En todos los trabajosanteriores, la ganancia de peso diaria fue baja, peromejores que las obtenidas en esta investigación.Mientras que el rendimiento en biomasa fue mayorque los reportados para cultivo en tierra, para todoslos tratamientos en este estudio fue muy bajo.

  10. Modelización de la producción de biomasa de Eucalyptus nitens (Deane & Maiden) Maiden en corta rotación para cultivo energético

    OpenAIRE

    González-García, M

    2016-01-01

    La biomasa forestal es una fuente de energía renovable cuyo uso genera beneficios de tipo ambiental, económico y social. En los últimos años el cultivo de Eucalyptus nitens (Deane & Maiden) Maiden para producción de biomasa se han extendido por el Noroeste de España. Los objetivos de esta Tesis Doctoral se centran en la modelización forestal de plantaciones energéticas de esta especie con el fin de estimar su productividad y proporcionar las herramientas para optimizar la producc...

  11. CFD analysis of pump consortium impeller

    Science.gov (United States)

    Cheng, Gary C.; Chen, Y. S.; Williams, R. W.

    1992-01-01

    Current design of high performance turbopumps for rocket engines requires effective and robust analytical tools to provide design impact in a productive manner. The main goal of this study is to develop a robust and effective computational fluid dynamics (CFD) pump model for general turbopump design and analysis applications. A Navier-Stokes flow solver, FDNS, embedded with the extended k-epsilon turbulence model and with appropriate moving interface boundary conditions, is developed to analyze turbulent flows in the turbomachinery devices. The FDNS code was benchmarked with its numerical predictions of the pump consortium inducer, and provides satisfactory results. In the present study, a CFD analysis of the pump consortium impeller will be conducted with the application of the FDNS code. The pump consortium impeller, with partial blades, is the new design concept of the advanced rocket engine.

  12. CFD simulation of a solar tower

    Energy Technology Data Exchange (ETDEWEB)

    Koten, Hasan; Yukselenturk, Yalcyn; Yilmaz, Mustafa [Marmara University Mechanical Engineering Department (Turkey)], E-mail: hasan.koten@marmara.edu.tr

    2011-07-01

    With the depletion of fossil fuels and the rising concerns about their impacts on the environment, the use of alternative energy sources has become necessary. Among the alternatives, solar energy, with its unlimited resources and its low impact on the environment, is the most promising. The aim of this paper is to present a numerical model of a regular solar tower. A CFD analysis of the solar tower was performed with a commercial CFD code and velocity fields, temperature measurements and flow characteristics were determined and compared to experimental results available in the literature. It was found that the numerical model is capable of assessing the buoyant air flow in chimneys. In addition results showed that increasing the solar chimney height, solar collector area, or solar irradiance increases power generation capacity while ambient temperature does not significantly affect this capacity. This study provided a numerical model which is proficient in modeling solar towers.

  13. CFD Simulations of Tiltrotor Configurations in Hover

    Science.gov (United States)

    Potsdam, Mark a.; Strawn, Roger C.

    2002-01-01

    Navier-Stokes computational fluid dynamics calculations are presented for isolated, half-span, and full-span V-22 tiltrotor hover configurations. These computational results extend the validity of CFD hover methodology beyond conventional rotorcraft applications to tiltrotor configurations. Computed steady-state, isolated rotor performance agrees well with experimental measurements, showing little sensitivity to grid resolution. However, blade-vortex interaction flowfield details are sensitive to numerical dissipation and are more difficult to model accurately. Time-dependent, dynamic, half- and full-span installed configurations show sensitivities in performance to the tiltrotor fountain flow. As such, the full-span configuration exhibits higher rotor performance and lower airframe download than the half-span configuration. Half-span rotor installation trends match available half-span data, and airframe downloads are reasonably well predicted. Overall, the CFD solutions provide a wealth of flowfield details that can be used to analyze and improve tiltrotor aerodynamic performance.

  14. CFD Simulation on Ethylene Furnace Reactor Tubes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Different mathematical models for ethylene furnace reactor tubes were reviewed. On the basis of these models a new mathematical simulation approach for reactor tubes based on computational fluid dynamics (CFD) technique was presented. This approach took the flow, heat transfer, mass transfer and thermal cracking reactions in the reactor tubes into consideration. The coupled reactor model was solved with the SIMPLE algorithm. Some detailed information about the flow field, temperature field and concentration distribution in the reactor tubes was obtained, revealing the basic characteristics of the hydrodynamic phenomena and reaction behavior in the reactor tubes. The CFD approach provides the necessary information for conclusive decisions regarding the production optimization, the design and improvement of reactor tubes, and the new techniques implementation.

  15. Thermal CFD Analysis of Tubular Light Guides

    OpenAIRE

    Ondřej Šikula; Jitka Mohelníková; Josef Plášek

    2013-01-01

    Tubular light guides are applicable for daylighting of windowless areas in buildings. Despite their many positive indoor climate aspects they can also present some problems with heat losses and condensation. A computer CFD model focused on the evaluation of temperature distribution and air flow inside tubular light guides of different dimensions was studied. The physical model of the tested light guides of lengths more than 0.60 m proves shows that Rayleigh numbers are adequate for a turbulen...

  16. Validation of Francis Water Turbine CFD Simulations

    OpenAIRE

    Čarija, Zoran; Mrša, Zoran; Fućak, Sanjin

    2008-01-01

    This paper compares data from calculated and measured results covering the whole operating range for a 20 MW Francis turbine in order to validate the CFD simulation. Computed hydraulic characteristics are determined for each analyzed operating point by running numerical simulations of turbulent fluid flow through a complete Francis Turbine model using the commercial fluid flow solver Fluent. The measured hydraulic characteristics were defined by on-site measurements according to the IEC41 int...

  17. CFD design analysis of ventilated disc brakes

    OpenAIRE

    Pulugundla, Gautam

    2008-01-01

    This thesis reports the numerical investigation of the automotive ventilated disc brake rotor. Disc brakes operate on the principle of friction by converting kinetic energy into heat energy. The main objective of a disc brake rotor is to store this heat energy and dissipate it as soon as possible. This work is carried out in a area where there is very limited understanding. Commercial CFD code FLUENT was used for carrying out the simulations with the rotor rotating in still ...

  18. Oil Cooling of Electric Motor using CFD

    OpenAIRE

    Al Shadidi, Kamilla

    2014-01-01

    This thesis investigated the heat transfer of internally oil cooled rotors in permanent magnet electric machines which are, among other things, used in hybrid vehicles or zero emission vehicles. The magnets become sensitive and can be demagnetized at high working temperatures, hence the need of cooling. The scope of this work included CFD simulations in STAR-CCM+. Three different 3D multiphase models simulating the oil propagation in the rotor were performed. A Lagrangian multiphase model com...

  19. Operations based optimisation using simulation and CFD

    OpenAIRE

    Doherty, JJ; Clifton, DP; Gillan, MA; Ciampoli, F

    2007-01-01

    An initial investigation of an optimisation based approach for design across a continuous range of operating conditions is presented. The objective for this 'operations based optimisation' approach is to avoid the need to choose critical design point conditions and associated weighting factors by tackling the overall operational performance instead. The approach integrates numerical optimisation, response surface modelling, CFD and operational simulation. An optimisation test bed involving th...

  20. CFD aided investigation of single droplet coalescence

    Institute of Scientific and Technical Information of China (English)

    Felix Gebauer; Mark W Hlawitschka; Hans-Jrg Bart

    2016-01-01

    This article describes the development of a coalescence model using various CFD work packages, and is validated using as toluene water model system. Numerical studies were performed to describe droplet interactions in liq-uid–liquid test systems. Current models use adjustable parameters to describe these phenomena. The research in the past decades led to different correlations to model coalescence and breakage depending on the chemical sys-tem and the apparatus geometry. Especial y the complexity of droplet coalescence requires a detailed investiga-tion of local phenomena during the droplet interaction. Computational fluid dynamics (CFD) studies of single droplet interactions were performed and validated with experimental results to improve the understanding of the local hydrodynamics and film drainage during coalescence. The CFD simulations were performed for the in-teraction of two differently sized droplets at industrial relevant impact velocities. The experimental verification and validation of the numerical results were done with standardized high-speed imaging studies by using a spe-cial test cel with a pendant and a free rising droplet. An experimental based algorithm was implemented in the open source code OpenFOAM to account for the contact time and the dimple formation. The standard European Federation of Chemical Engineering (EFCE) test system toluene/water was used for the numerical studies and the experimental investigations as wel . The results of the CFD simulations are in good accordance with the observed coalescence behavior in the experimental studies. In addition, a detailed description of local phenomena, like film rupture, velocity gradients, pressures and micro-droplet entrainment could be obtained.

  1. CFD simulation of highly transient flows

    OpenAIRE

    Denton, G. S.

    2009-01-01

    This thesis describes the fundamental extension and extensive testing of a robust CFD model for predicting outflow following the failure of pressurised hydrocarbon pipelines. The main thrust of the study involves the extension of the basic outflow model to account for complex pipeline systems, improvements of the theoretical basis and numerical stability. The basic model, based on the numerical solution of conservation equations using the method of characteristics, incorporates a suitabl...

  2. Aircraft Design Analysis, CFD And Manufacturing

    Directory of Open Access Journals (Sweden)

    Haifa El-Sadi

    2016-09-01

    Full Text Available Aircraft design, manufacturing and CFD analysis as part of aerodynamic course, the students achieve sizing from a conceptual sketch, select the airfoil geometry and the tail geometry, calculate thrust to weight ratio and wing loading, use initial sizing and calculate the aerodynamic forces. The students design their aircraft based on the geometrical dimensions resulted from the calculations and use the model to build a prototype, test it in wind tunnel and achieve CFD analysis to be compared with the experimental results. The theory of aerodynamic is taught and applied as a project based. In this paper, the design process, aircraft manufacturing and CFD analysis are presented to show the effect of project based on student’s learning of aerodynamic course. This project based learning has improved and accelerated students understanding of aerodynamic concepts and involved students in a constructive exploration. The analysis of the aircraft resulted in a study that revolved around the lift and drag generation of this particular aircraft. As to determine the lift and drag forces generated by this plane, a model was created in Solidworks a 3-D model-rendering program. After this model was created it was 3-D printed in a reduced scale, and subjected to wind tunnel testing. The results from the wind tunnel lab experiment were recorded. For accuracy, the same 3-D model was then simulated using CFD simulation software within Solidworks and compared with the results from the wind tunnel test. The values derived from both the simulation and the wind tunnel tests were then compared with the theoretical calculations for further proof of accuracy.

  3. Static load balancing for CFD distributed simulations

    Energy Technology Data Exchange (ETDEWEB)

    Chronopoulos, A T; Grosu, D; Wissink, A; Benche, M

    2001-01-26

    The cost/performance ratio of networks of workstations has been constantly improving. This trend is expected to continue in the near future. The aggregate peak rate of such systems often matches or exceeds the peak rate offered by the fastest parallel computers. This has motivated research towards using a network of computers, interconnected via a fast network (cluster system) or a simple Local Area Network (LAN) (distributed system), for high performance concurrent computations. Some of the important research issues arise such as (1) Optimal problem partitioning and virtual interconnection topology mapping; (2) Optimal execution scheduling and load balancing. CFD codes have been efficiently implemented on homogeneous parallel systems in the past. In particular, the helicopter aerodynamics CFD code TURNS has been implemented with MPI on the IBM SP with parallel relaxation and Krylov iterative methods used in place of more traditional recursive algorithms to enhance performance. In this implementation the space domain is divided into equal subdomain which are mapped to the processors. We consider the implementation of TURNS on a LAN of heterogeneous workstations. In order to deal with the problem of load balancing due to the different processor speeds we propose a suboptimal algorithm of dividing the space domain into unequal subdomains and assign them to the different computers. The algorithm can apply to other CFD applications. We used our algorithm to schedule TURNS on a network of workstations and obtained significantly better results.

  4. CFD for wastewater treatment: an overview.

    Science.gov (United States)

    Samstag, R W; Ducoste, J J; Griborio, A; Nopens, I; Batstone, D J; Wicks, J D; Saunders, S; Wicklein, E A; Kenny, G; Laurent, J

    2016-01-01

    Computational fluid dynamics (CFD) is a rapidly emerging field in wastewater treatment (WWT), with application to almost all unit processes. This paper provides an overview of CFD applied to a wide range of unit processes in water and WWT from hydraulic elements like flow splitting to physical, chemical and biological processes like suspended growth nutrient removal and anaerobic digestion. The paper's focus is on articulating the state of practice and research and development needs. The level of CFD's capability varies between different process units, with a high frequency of application in the areas of final sedimentation, activated sludge basin modelling and disinfection, and greater needs in primary sedimentation and anaerobic digestion. While approaches are comprehensive, generally capable of incorporating non-Newtonian fluids, multiphase systems and biokinetics, they are not broad, and further work should be done to address the diversity of process designs. Many units have not been addressed to date. Further needs are identified throughout, but common requirements include improved particle aggregation and breakup (flocculation), and improved coupling of biology and hydraulics. PMID:27508360

  5. Consideraciones sobre la producción de etanol a partir de la biomasa lignocelulósica

    Directory of Open Access Journals (Sweden)

    José C. Villar

    2008-01-01

    Full Text Available En los últimos años, como consecuencia del aumento de los precios del petróleo y las exigencias ecológicas, ha crecido el interés por la producción de bioetanol como combustible de vehículos automotores. En Brasil y EEUU, los principales productores, se estima una producción por cada país en el 2006 de alrededor de los 19 mil millones de litros. Brasil planea aumentar la producción hasta 26.5 mil millones en el 2016 mientras que para esa misma fecha EEUU pretende alcanzar los 45,4 mil millones de litros. Las materias primas más empleadas son maíz y caña de azúcar. Sería de interés incluir entre éstas a la biomasa lignocelulósica que se obtiene como subproductos agrícolas y forestales (pajas de cereales, bagazo, aserrín y virutas de madera que no son aptos para el consumo humano y por su composición química son susceptibles de ser sacarificados por hidrólisis química o enzimática. Se analizan críticamente las posibles vías para desarrollar la producción de alcohol a partir de estos materiales, en especial la vía química, cuya perspectiva de éxito se encuentra estrechamente vinculada al desarrollo de reactores continuos. De esta manera, se pueden intensificar las condiciones de reacción que permitan incrementar la productividad del proceso, mediante la obtención de los máximos rendimientos de azúcares con el empleo de los menores volúmenes del equipamiento, sin descuidar la disminución de la concentración de sustancias inhibidoras de la fermentación en el sistema.

  6. Recent Efforts for Credible CFD Simulations in China

    OpenAIRE

    Bai Wen; Li Li; Liang Yihua

    2011-01-01

    In this paper some recent efforts for credible computational fluid dynamics (CFD) simulations in China are reviewed. The most important effort is that, following similar activities in the West such as ECARP and AIAA Drag Prediction Workshops, a series of workshops on credible CFD simulations had been initiated. These workshops were with ambitions to assess the status of CFD in China. Another major effort is an ongoing project to establish a software platform for studying the credibility of CF...

  7. The Role of CFD Simulation in Rocket Propulsion Support Activities

    Science.gov (United States)

    West, Jeff

    2011-01-01

    Outline of the presentation: CFD at NASA/MSFC (1) Flight Projects are the Customer -- No Science Experiments (2) Customer Support (3) Guiding Philosophy and Resource Allocation (4) Where is CFD at NASA/MSFC? Examples of the expanding Role of CFD at NASA/MSFC (1) Liquid Rocket Engine Applications : Evolution from Symmetric and Steady to 3D Unsteady (2)Launch Pad Debris Transport-> Launch Pad Induced Environments (a) STS and Launch Pad Geometry-steady (b) Moving Body Shuttle Launch Simulations (c) IOP and Acoustics Simulations (3)General Purpose CFD Applications (4) Turbomachinery Applications

  8. Computational System For Rapid CFD Analysis In Engineering

    Science.gov (United States)

    Barson, Steven L.; Ascoli, Edward P.; Decroix, Michelle E.; Sindir, Munir M.

    1995-01-01

    Computational system comprising modular hardware and software sub-systems developed to accelerate and facilitate use of techniques of computational fluid dynamics (CFD) in engineering environment. Addresses integration of all aspects of CFD analysis process, including definition of hardware surfaces, generation of computational grids, CFD flow solution, and postprocessing. Incorporates interfaces for integration of all hardware and software tools needed to perform complete CFD analysis. Includes tools for efficient definition of flow geometry, generation of computational grids, computation of flows on grids, and postprocessing of flow data. System accepts geometric input from any of three basic sources: computer-aided design (CAD), computer-aided engineering (CAE), or definition by user.

  9. Comprehensive Approach to Verification and Validation of CFD Simulations Applied to Backward Facing Step-Application of CFD Uncertainty Analysis

    Science.gov (United States)

    Groves, Curtis E.; LLie, Marcel; Shallhorn, Paul A.

    2012-01-01

    There are inherent uncertainties and errors associated with using Computational Fluid Dynamics (CFD) to predict the flow field and there is no standard method for evaluating uncertainty in the CFD community. This paper describes an approach to -validate the . uncertainty in using CFD. The method will use the state of the art uncertainty analysis applying different turbulence niodels and draw conclusions on which models provide the least uncertainty and which models most accurately predict the flow of a backward facing step.

  10. Chloroform fumigation-extraction labile C pool (microbial biomass C "plus" shows high correlation to microbial biomass C in Argentinian and Brazilian soils Alta correlación entre el "pool" de carbono lábil por fumigación con cloroformo-extracción (carbono de biomasa microbiana plus y carbono de biomasa microbiana en suelos de Argentina y Brasil

    Directory of Open Access Journals (Sweden)

    Helvécio De-Polli

    2007-07-01

    Full Text Available Chloroform fumigation-incubation and chloroform fumigation-extraction approaches have significantly contributed to assess soil microbial biomass. Some controversy is found in the literature about the suggestion to calculate microbial biomass carbon (MBC without the subtraction of the un-fumigated control, in opposition to the originally proposed method that requires such subtraction. Some authors consider the non-subtraction proceeding as a more robust method. Nevertheless, values obtained without subtraction of a control include other labile organic fractions of soil carbon besides microbial biomass. Therefore, due to the usefulness of this measurement we consider more appropriate to call it as chloroform-fumigation labile C pool or microbial biomass carbon "plus" (MBC PLUS. We used a vast series of data from soils of Argentina and Brazil under different management situations to verify whether MBC correlates to MBC PLUS. There was a significant statistical correlation between values of MBC obtained by fumigation-extraction method and the corresponding MBC PLUS. The MBC PLUS performed as well as MBC as an indicator to differentiate soil managements and their impact on soil quality.Los métodos de fumigación-incubación y fumigación extracción han contribuido significativamente a las determinaciones de biomasa microbiana del suelo. En la literatura se encuentran algunas controversias acerca de la sugerencia de calcular el carbono de biomasa microbiana (CBM sin la sustracción del control no fumigado, en oposición a las metodologías tradicionales que requieren de dicha sustracción. Algunos autores mencionan que el hecho de no realizar la sustracción hace al procedimiento más robusto. Sin embargo, los valores obtenidos sin la sustracción del control incluyen otras fracciones lábiles del carbono, además de la biomasa microbiana. Debido a lo útil que resulta esta medida consideramos adecuado llamarla "pool" de carbono lábil por fumigaci

  11. CFD modeling of the EPR primary circuit

    International Nuclear Information System (INIS)

    Highlights: • A RANS CFD computation of almost all of the EPR reactor primary circuit is demonstrated. • Comparison with experimental data of the obtained results is carried out. • Hydraulic decoupling between main vessel elements in normal operation is pointed out. • Promising results are found out with regards to nuclear plants’ safety demonstration. - Abstract: The present paper deals with the feasibility of a RANS CFD computation of almost all of the primary circuit of a EPR PWR reactor. The developed model includes the vessel, the core, the steam generators and the associated piping. The flow in the primary circuit is studied under normal operations with balanced flow rates between loops. The k–ε realizable model is retained for the turbulence modeling, and standard wall functions are used as wall treatment. The constructed grid contains about 181,000,000 elements, mainly hexahedrons. The computation is performed with the commercial CFD code STAR-CD, and despite the relatively large amount of cells, such kind of computation is fully accessible at an industrial scale with today available computational resources. A comparison with experimental data of the obtained results is carried out. The simulation results in the vessel are confronted to measurements issued from JULIETTE and ROMEO mock-ups, representative of the EPR lower and upper internals respectively. Regarding the steam generators, a benchmark with the dedicated code GENEPI is also performed. An overall good agreement with the reference data is underlined. The potential up-and-downstream effects of the different modeled components brought interesting knowledge, especially with regards to safety issues. These encouraging results allow in testing, in a near future, this model in other configurations such as unbalanced operation or accidental transients

  12. CFD investigation of Flexblue® hull

    International Nuclear Information System (INIS)

    Flexblue® is an underwater nuclear power station operating up to 100 m depth several km away from the shore. The immersion is beneficial for safety because it protects the reactor against severe external aggressions such as tsunamis, extreme weather conditions and malevolent actions. It also provides an infinite heat sink to cool down the reactor in any situation. In case of an accident, the safety systems take advantage of this natural source of cooling to bring and maintain the reactor in a safe state without human intervention for an indefinite period of time. The metallic containment itself is naturally cooled on its external side by the ocean. The present work investigates seawater natural convection fluid dynamics and heat transfer features, to evaluate the capabilities of the containment to reject the decay power to the exterior. A preliminary lumped parameters approach is adopted, revealing that the large diameter of the hull (14 m) is such that the ranges of validity of empirical correlations for natural convection heat transfer are always exceeded and that conditions for their correct application are not satisfied. Hence, a 2D, unsteady CFD analysis is performed to simulate the natural convection flow in the ocean, and to obtain predictions for heat flux distribution, hull superficial temperature profile and heat transfer coefficient. Both CFD sensitivity and parametric analyses are carried out, albeit limited to a 2D approach to limit the computational burden. The results show that the heat transfer process is globally satisfactory and enables all decay heat removal. A 3D approach and an experimental campaign aiming at validating the CFD results is planned for the next stage. (author)

  13. REFRIGERAÇÃO UTILIZANDO PASTILHAS DE EFEITO PELTIER

    OpenAIRE

    Antonio Luiz P. S. Campos; Aécio Vinícius Amorim Farias; Jainne Daniele F. S. Fernandes; Alailson de Freitas Braz; Ludmila Sayonara S. X. Machado; Edfranklin de Souza Pimentel

    2010-01-01

    Pastilhas de Peltier são dispositivos baseados no efeito Peltier e são aplicadas para produzir efeito refrigerador ou aquecedor. Este trabalho aborda conceitos envolvidos na fabricação e funcionamento desses dispositivos tais como: histórico do efeito Peltier e desenvolvimento de placas de efeito Peltier. É feito um estudo de eficiência da refrigeração de água utilizando uma placa de efeito Peltier existente no Campus Natal – Zona Norte. Para isso, é implementada uma estrutura de refrigeração...

  14. Modeling Pulse Tube Cryocoolers with CFD

    Science.gov (United States)

    Flake, Barrett; Razani, Arsalan

    2004-06-01

    A commercial computational fluid dynamics (CFD) software package is used to model the oscillating flow inside a pulse tube cryocooler. Capabilities for modeling pulse tubes are demonstrated with preliminary case studies and the results presented. The 2D axi-symmetric simulations demonstrate the time varying temperature and velocity fields in the tube along with computation of the heat fluxes at the hot and cold heat exchangers. The only externally imposed boundary conditions are a cyclically moving piston wall at one end of the tube and constant temperature or heat flux boundaries at the external walls of the hot and cold heat exchangers.

  15. Suppression pool swell analysis using CFD code

    International Nuclear Information System (INIS)

    A two-dimensional axi-symmetric model of suppression pool of Containment Studies Facility (CSF) along with single vent pipe was modeled to estimate the jet and hydrodynamic loads due to flow of steam air mixture during simulated loss of coolant accident (LOCA). The analysis was carried out using CFD ACE+ software with Volume of Fluid (VOF) approach. The flow velocity variation through vent pipe was estimated using in-house containment thermal hydraulic code CONTRAN, was given as input at inlet boundary condition. The transient calculations were performed for 20 seconds and suppression pool level variation, pressure loads over the floor, walls and vent pipes etc were evaluated. (author)

  16. CFD analysis of poison injection in AHWR calandria

    International Nuclear Information System (INIS)

    The present work intends to give details of design and performance validation of SDS-2. The performance is evaluated on the basis of dispersion of poison in calandria in a given period of time. Location of injection tube and injection holes, size of jet hole and number of holes are some of the design parameters which greatly affect dispersion of poison in calandria. A Computational Fluid Dynamic (CFD) study for axial and radial injection of poison was carried out using open source CFD code OpenFOAM. CFD benchmarking was done using experiments performed by Johari (Johari et al. 1997) to identify suitable turbulence model for this problem. An experimental facility simulating poison injection in moderator in presence of calandria tubes was used to further validate the CFD model is shown in the paper. CFD analysis was carried out for axial as well as radial injection for AHWR geometry. CFD analysis using OpenFOAM has been carried out to study high pressure poison injection for single jet of Shut Down System - 2 (SDS- 2) of Advanced Heavy Water Reactor (AHWR) for various design options. CFD model used in analysis have been validated with experimental data available in literature as well as experiments performed for AHWR specific geometry. Various turbulence models are tested and their adequacy for such flow problems has been established. The CFD model is then used to simulate poison injection for two design options for AHWR and their performance is compared. (author)

  17. CFD computations of the second round of MEXICO rotor measurements

    DEFF Research Database (Denmark)

    Sørensen, Niels N.; Zahle, Frederik; Boorsma, K.;

    2016-01-01

    A comparison, between selected wind tunnel data from the NEW MEXICO measuring campaign and CFD computations are shown. The present work, documents that a state of the art CFD code, including a laminar turbulent transition model, can provide good agreement with experimental data. Good agreement...

  18. Modelling of Air Flow trough a Slatted Floor by CFD

    DEFF Research Database (Denmark)

    Svidt, Kjeld; Bjerg, Bjarne; Morsing, Svend;

    In this paper two different CFD-approaches are investigated to model the airflow through a slatted floor. Experiments are carried out in a full-scale test room. The computer simulations are carried out with the CFD-code FLOVENT, which solves the time-averaged Navier-Stokes equations by use of the...

  19. Optimización del medio de cultivo QBP para la producción de biomasa del consorcio BIOYAF

    Directory of Open Access Journals (Sweden)

    Yaima Barrios San Martín

    2014-06-01

    Full Text Available Título en inglés: Optimization of culture media QBP to the production of biomass of consortium BIOYAF Título corto: Optimización de un medio de cultivoResumen: La optimización de los medios de cultivo con fines industriales en la mayoría de los casos ha sido efectuada mediante procedimientos empíricos de ensayo y error. Empleando diversos métodos estadísticos es probable que el medio de cultivo original pueda ser optimizado, en muchos casos es posible obtener un medio que no solo sea más productivo, sino de menor o igual costo que el original. Se optimizó el medio de cultivo QBP para el crecimiento de las cepas del consorcio bacteriano BIOYAF capaz de degradar hidrocarburos del petróleo, empleando un Diseño de Factor Categórico Individual para determinar el tiempo de trabajo, un Diseño Factorial (24 para determinar los rangos de trabajo de concentración de los nutrientes y un Diseño de Superficie de Respuesta para optimizar las concentraciones. Las variables de respuesta de evaluación de los experimentos fueron masa húmeda, masa (UDO, conteo de viables, conductividad, pH y tensión superficial. El tiempo óptimo para el crecimiento de las cepas del consorcio BIOYAF es de seis horas. El medio de cultivo QBP con concentraciones óptimas de fosfato de amonio (3,19 g.l-1, sulfato de magnesio (0,04 g.l-1, levadura (3,77 g.l-1 y sacarosa (47,89 g.l-1 permite que la producción de biomasa aumente de 1,540 UDO a 3,082 UDO.Palabras clave: superficie de respuesta, consorcio bacteriano, crecimiento óptimo.Abstract: The optimization of culture media with industrial purposes, in most cases, has been made through empirical trial and error procedures. Using different statistical methods original culture media can be optimized, in many cases, it is possible to obtain a more productive media, at the same cost as the original one. The culture media QBP was optimized for the growth of the bacterial consortium BIOYAF, which can degrade

  20. Qualification of CFD-models for multiphase flows

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, Dirk [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany)

    2016-05-15

    While Computational Fluid Dynamics (CFD) is already an accepted industrial tool for single phase flows it is not yet mature for two-phase flows. For this reason the qualification of CFD for reactor safety relevant applications which involve multiphase flows is a present topic of research. At the CFD division of Helmholtz-Zentrum Dresden-Rossendorf (HZDR) hereby beside an application-oriented model development and validation also more generic investigations are done. Thus, the baseline model strategy aims on the consolidation of the CFD-modelling for multiphase to enable reliable predictions for well-defined flow pattern in future. In addition the recently developed GENTOP-concept broadens the range of applicability of CFD. Different flow morphologies including transitions between them can be considered in frame of this concept.

  1. CFD application to PWR subchannel void distribution benchmark

    International Nuclear Information System (INIS)

    A CFD study is performed to simulate the steady-state void distribution benchmark based on the NUPEC PWR Subchannel and Bundle Tests (PSBT). The CFD calculation predicted the void distributions in central typical and thimble subchannels, side subchannel and corner subchannel. The CFD prediction shows a higher void fraction near the heated wall and a migration of void in the subchannel gap region. A measured image of void distribution indicated a locally higher void fraction near the heated wall. The CFD predictions of void fraction and fluid density agree well with the measured ones for the low void test condition. However, the CFD calculations tend to underpredict the void fraction and overpredict the fluid density as the void fraction increases. (author)

  2. Qualification of CFD-models for multiphase flows

    International Nuclear Information System (INIS)

    While Computational Fluid Dynamics (CFD) is already an accepted industrial tool for single phase flows it is not yet mature for two-phase flows. For this reason the qualification of CFD for reactor safety relevant applications which involve multiphase flows is a present topic of research. At the CFD division of Helmholtz-Zentrum Dresden-Rossendorf (HZDR) hereby beside an application-oriented model development and validation also more generic investigations are done. Thus, the baseline model strategy aims on the consolidation of the CFD-modelling for multiphase to enable reliable predictions for well-defined flow pattern in future. In addition the recently developed GENTOP-concept broadens the range of applicability of CFD. Different flow morphologies including transitions between them can be considered in frame of this concept.

  3. Análisis Exergético de la Gasificación de Biomasa Exergy Analysis of Biomass Gasification

    Directory of Open Access Journals (Sweden)

    Jorge M Mendoza

    2012-01-01

    Full Text Available El objetivo de este estudio fue realizar el análisis exergético de la gasificación de biomasa residual con la finalidad de obtener energía útil. Se desarrolló un modelo para la gasificación de biomasa basado en el equilibrio químico de las reacciones. Este modelo permite predecir la evolución de la composición del gas de síntesis en función de la temperatura, las presiones y la composición elemental de los residuos del proceso de extracción de aceite de palma y orujo de lavado de uva (hidrogeno, oxigeno, carbono y nitrógeno, como también hacer un análisis exergético. Se encontró que independiente del agente gasificante, la concentración de monóxido de carbono e hidrógeno tienden a incrementar significativamente a altas presiones y elevadas temperaturas. Además, se muestra que la eficiencia exergética incrementa con la temperatura y disminuye con el aumento de la relación aire/combustible.This paper shows the exergy analysis applied to the gasification process of residual biomass with the purpose of obtaining useful energy. A model for the biomass gasification based on chemical equilibrium of the reactions is proposed. The model allows predicting the syngas composition as a function of temperature, pressure and ultimate analysis of palm oil and grapevine pruning waste (determining hydrogen, oxygen, carbon and nitrogen. It was found that the carbon monoxide and hydrogen concentration significantly increase at high pressure and temperature independently of the gasifying agent. Furthermore, it was also noticed that the exergy efficiency increases as temperature increases, and decreases as the relative fuel/air ratio increases.

  4. Efecto de la depuración en la biomasa del caracol Pomacea patula [Baker, 1922] usando el índice de condición

    Directory of Open Access Journals (Sweden)

    M. García-Ulloa

    2006-01-01

    Full Text Available La depuración de organismos acuáticos en cultivo es una práctica común. El tiempo de exposición de los animales al agua tratada es uno de los factores más importantes para su eficiencia, pudiendo afectar su biomasa. Se evaluó el efecto de la depuración en adultos de Pomacea patula mediante la aplicación del índice de condición (IC, bajo condiciones de laboratorio. Caracoles adultos obtenidos en cultivo se mantuvieron en peceras (Grupo 1 expuestos a un flujo de agua constante, tratada con radiación ultravioleta y limpieza diaria y en condiciones normales de mantenimiento (Grupo 2, con 5 réplicas por grupo. Se obtuvo el peso húmedo y longitud total individualmente, al inicio y después de una depuración de 10 días. El valor promedio del coeficiente de correlación (animales iniciales y de los Grupos 1 y 2 fue mayor a 0.90. El IC entre el valor inicial (771.81 ± 40.41 y los Grupos 1 y 2 (763.527 ± 25.24 y 765.465 ± 38.59, respectivamente, no mostró diferencias significativas (P > 0.05 al final del experimento. Los resultados sugieren que el proceso de depuración usado no afectó la biomasa de adultos de P. patula. El IC se mostró como una herramienta práctica de evaluación sin considerar la diferencia inicial de tallas de caracoles adultos

  5. Efecto de lixiviados del raquis de plátano sobre la actividad y biomasa microbiana en floración y cosecha del tomate

    Directory of Open Access Journals (Sweden)

    Muñoz V. Rosa Elvira

    2005-03-01

    Full Text Available Se utilizaron cinco tratamientos: el testigo (T0 y cuatro concentraciones de lixiviados (T1= 100%, T2= 75%, T3= 50% y T4= 25% aplicados 15, 30 y 60 días después del trasplante. La actividad microbiana se determinó con la metodología del CAB y la biomasa microbiana con el método de fumigación-extracción. En la actividad microbiana se encontraron diferencias significativas entre los tratamientos, presentando la aplicación del lixiviado a la menor concentración (25% la mayor actividad (56.76 mgCO2g suelo-1. La actividad fue mayor en floración en todos los tratamientos. Para biomasa microbiana no se presentaron diferencias significativas entre los tratamientos ni entre épocas. ABSTRACT The effect of leaching from rachis on soil microbial biomass and activity during tomato flowering and harvesting period. Field trail comprised five treatments of different leaching concentrations (T0= test, T1= 100%, T2= 75%, T3=50%, and T4=25% sprinkled on soil 15, 30 and 60 days after tomato transplanting. Microbial activity was measured with CAB method and microbial biomass was recorded with fumigation - extraction method. The average microbial activity with sprinking of 25% of leaching was higher (56.76 mgCO2g suelo-1. No significant difference in order to treatments and periods in microbial biomass were observed. These observations showed leaching sprinkling in low concentration influence en microbial activity for the conditions of this experiment. Key words: Soil biology, biomass, leaching, Lycopersicum sculentun.

  6. Survey of CFD studies on automotive buffeting

    International Nuclear Information System (INIS)

    In the current automobile market buffeting is one of the customer frequent complaints on luxury cars and SUVs. Buffeting is a low frequency but high level wind noise and makes people inside the vehicle uncomfortable if it lasts for a long period of time. The physical mechanism of buffeting is a complicated phenomenon of aeroacoustic resonance. The aeroacoustic characteristics of buffeting depend on vehicle features and operating conditions. In this paper, a survey of CFD studies on the automotive buffeting is presented. Firstly, several buffeting related concepts, such as Helmholtz resonator, flow over a cavity, shear layer instability and vortex shedding, are reviewed and relevant references are listed. Then, a historic survey of the buffeting investigation is made with emphasis on computational studies. As an example, the buffeting studies at DaimlerChrysler are selected to demonstrate the procedure of CFD simulation for automotive buffeting. The procedure is then validated by the correlation with wind tunnel testing. After that the validated procedure is applied to find solutions for buffeting reduction. Finally, some comments on buffeting studies are addressed. (author)

  7. Thermal CFD Analysis of Tubular Light Guides

    Directory of Open Access Journals (Sweden)

    Ondřej Šikula

    2013-12-01

    Full Text Available Tubular light guides are applicable for daylighting of windowless areas in buildings. Despite their many positive indoor climate aspects they can also present some problems with heat losses and condensation. A computer CFD model focused on the evaluation of temperature distribution and air flow inside tubular light guides of different dimensions was studied. The physical model of the tested light guides of lengths more than 0.60 m proves shows that Rayleigh numbers are adequate for a turbulent air flow. The turbulent model was applied despite the small heat flux differences between the turbulent and laminar model. The CFD simulations resulted into conclusions that the growing ratio of length/diameter increases the heat transmission loss/linear transmittance as much as by 50 percent. Tubular light guides of smaller diameters have lower heat transmission losses compared to the wider ones of the same lengths with the same outdoor temperature being taken into account. The simulation results confirmed the thermal bridge effect of the tubular light guide tube inside the insulated flat roof details. The thermal transmittance of the studied light guides in the whole roof area was substituted with the point thermal bridges. This substitution gives possibility for simple thermal evaluation of the tubular light pipes in roof constructions.

  8. On spurious behavior of CFD simulations

    Energy Technology Data Exchange (ETDEWEB)

    Yee, H.C. [National Aeronautics and Space Administration, Moffett Field, CA (United States). Ames Research Center; Torczynski, J.R. [Sandia National Labs., Albuquerque, NM (United States); Morton, S.A.; Visbal, M.R. [Wright Lab., Wright-Patterson AFB, OH (United States); Sweby, P.K. [Univ. of Reading (United Kingdom)

    1997-05-01

    Spurious behavior in underresolved grids and/or semi-implicit temporal discretizations for four computational fluid dynamics (CFD) simulations are studied. The numerical simulations consist of (a) a 1-D chemically relaxed nonequilibrium model, (b) the direct numerical simulation (DNS) of 2-D incompressible flow over a backward facing step, (c) a loosely-coupled approach for a 2-D fluid-structure interaction, and (d) a 3-D compressible unsteady flow simulation of vortex breakdown in delta wings. Using knowledge from dynamical systems theory, various types of spurious behaviors that are numerical artifacts were systematically identified. These studies revealed the various possible dangers of misinterpreting numerical simulation of realistic complex flows that are constrained by the available computing power. In large scale computations underresolved grids, semi-implicit procedures, loosely-coupled implicit procedures, and insufficiently long time integration in DNS are most often unavoidable. Consequently, care must be taken in both computation and in interpretation of the numerical data. The results presented confirm the important role that dynamical systems theory can play in the understanding of the nonlinear behavior of numerical algorithms and in aiding the identification of the sources of numerical uncertainties in CFD.

  9. METC CFD simulations of hot gas filtration

    Energy Technology Data Exchange (ETDEWEB)

    O`Brien, T.J.

    1995-06-01

    Computational Fluid Dynamic (CFD) simulations of the fluid/particle flow in several hot gas filtration vessels will be presented. These simulations have been useful in designing filtration vessels and in diagnosing problems with filter operation. The simulations were performed using the commercial code FLUENT and the METC-developed code MFIX. Simulations of the initial configuration of the Karhula facility indicated that the dirty gas flow over the filter assemblage was very non-uniform. The force of the dirty gas inlet flow was inducing a large circulation pattern that caused flow around the candles to be in opposite directions on opposite sides of the vessel. By introducing a system of baffles, a more uniform flow pattern was developed. This modification may have contributed to the success of the project. Several simulations of configurations proposed by Industrial Filter and Pump were performed, varying the position of the inlet. A detailed resolution of the geometry of the candles allowed determination of the flow between the individual candles. Recent simulations in support of the METC/CeraMem Cooperative Research and Development Agreement have analyzed the flow in the vessel during the cleaning back-pulse. Visualization of experiments at the CeraMem cold-flow facility provided confidence in the use of CFD. Extensive simulations were then performed to assist in the design of the hot test facility being built by Ahlstrom/Pyropower. These tests are intended to demonstrate the CeraMem technology.

  10. Recycling Krylov subspaces for CFD applications

    CERN Document Server

    Amritkar, Amit; Świrydowicz, Katarzyna; Tafti, Danesh; Ahuja, Kapil

    2015-01-01

    The most popular iterative linear solvers in Computational Fluid Dynamics (CFD) calculations are restarted GMRES and BiCGStab. At the beginning of most incompressible flow calculations, the computation time and the number of iterations to converge for the pressure Poisson equation are quite high. In this case, the BiCGStab algorithm, with relatively cheap but non-optimal iterations, may fail to converge for stiff problems. Thus, a more robust algorithm like GMRES, which guarantees monotonic convergence, is preferred. To reduce the large storage requirements of GMRES, a restarted version - GMRES(m) or its variants - is used in CFD applications. However, GMRES(m) can suffer from stagnation or very slow convergence. For this reason, we use the rGCROT method. rGCROT is an algorithm that improves restarted GMRES by recycling a selected subspace of the search space from one restart of GMRES(m) to the next as well as building and recycling this outer vector space from one problem to the next (subsequent time steps i...

  11. CFD Simulation of Liquid Rocket Engine Injectors

    Science.gov (United States)

    Farmer, Richard; Cheng, Gary; Chen, Yen-Sen; Garcia, Roberto (Technical Monitor)

    2001-01-01

    Detailed design issues associated with liquid rocket engine injectors and combustion chamber operation require CFD methodology which simulates highly three-dimensional, turbulent, vaporizing, and combusting flows. The primary utility of such simulations involves predicting multi-dimensional effects caused by specific injector configurations. SECA, Inc. and Engineering Sciences, Inc. have been developing appropriate computational methodology for NASA/MSFC for the past decade. CFD tools and computers have improved dramatically during this time period; however, the physical submodels used in these analyses must still remain relatively simple in order to produce useful results. Simulations of clustered coaxial and impinger injector elements for hydrogen and hydrocarbon fuels, which account for real fluid properties, is the immediate goal of this research. The spray combustion codes are based on the FDNS CFD code' and are structured to represent homogeneous and heterogeneous spray combustion. The homogeneous spray model treats the flow as a continuum of multi-phase, multicomponent fluids which move without thermal or velocity lags between the phases. Two heterogeneous models were developed: (1) a volume-of-fluid (VOF) model which represents the liquid core of coaxial or impinger jets and their atomization and vaporization, and (2) a Blob model which represents the injected streams as a cloud of droplets the size of the injector orifice which subsequently exhibit particle interaction, vaporization, and combustion. All of these spray models are computationally intensive, but this is unavoidable to accurately account for the complex physics and combustion which is to be predicted, Work is currently in progress to parallelize these codes to improve their computational efficiency. These spray combustion codes were used to simulate the three test cases which are the subject of the 2nd International Workshop on-Rocket Combustion Modeling. Such test cases are considered by

  12. CFD Applications in Energy and Environment Sectors: Volume 1

    Directory of Open Access Journals (Sweden)

    Maher A.R. Sadiq Al-Baghdadi and Hashim R. Abdol Hamid

    2012-01-01

    Full Text Available Chapter 1: Simulation and Modelling of Oxygen Coal Combustion with Flue Gas Recirculation. Chaouki Ghenai Chapter 2: The Choice of the Best Air Distribution Concept in Air-Conditioned Auditorium by Means of CFD Numerical Prediction. Barbara Lipska, Piotr Koper Chapter 3: CFD Applications in Natural Ventilation of Buildings and Air Quality Dispersion. N. Nikolopoulos, A. Nikolopoulos, I. Papadakis, K.-S. P. Nikas Chapter 4: CFD Modeling of Air Pollutant Transport and Dispersion. Labovský Juraj, Jelemenský Ľudovít Chapter 5: CFD Modeling of Multiphase Flow in Environmental Engineering. Masroor Mohajerani, Mehrab Mehrvar, Farhad Ein-Mozaffari Chapter 6: CFD Study on the Roles of Trees on Airflow and Pollutant Dispersion within Urban Street Canyons. Salim Mohamed Salim, Andrew Chan, Riccardo Buccolieri, Silvana Di Sabatino Chapter 7: Energy Efficiency and Air Quality in Hospitals Design. Essam E. Khalil Chapter 8: Application of CFD in Pulverized Fuel Combustion. M. Tayyeb Javed, Tahira Sultana Chapter 9: A Heat Transfer Model For Fluids Based on Cellular Automaton Application to an Air Conditioning of A Building. Andrés Saiz Martínez Chapter 10: CFD Application in Power Plants. Essam E. Khalil Chapter 11: Analysis and Computation of the Heat Charge/Discharge Behavior in Packed Bed Thermal Storage Systems. Pei-Wen Li, Jon Van Lew, Wafaa Karaki, Cho Lik Chan, Jake Stephens

  13. The Role of CFD in Undergraduate Fluid Mechanics Education

    Science.gov (United States)

    Cimbala, John

    2006-11-01

    Instruction of undergraduate fluid mechanics is greatly enhanced through integration of computational fluid dynamics (CFD) into fluid mechanics courses and labs. Specifically, students are able to visualize fluid flows with CFD and are better able to understand those flows by performing parametric studies. At Penn State, CFD has been carefully integrated into our introductory junior-level fluid mechanics course, yet displaces only about one class period. The key is to show demonstrations and assign homework that use CFD as a tool that helps students learn the basic concepts of fluid mechanics. The application of CFD (grid generation, boundary conditions, etc.), rather than numerical algorithms, is stressed. This is done through use of short, pre-defined templates for FlowLab, a student-friendly analysis and visualization package created by Fluent, Inc. The textbook by Cengel and Cimbala (McGraw-Hill 2006) contains 46 end-of-chapter homework problems that are used in conjunction with 42 FlowLab templates. Each exercise has been designed with two major learning objectives in mind: (1) enhance student understanding of a specific fluid mechanics concept, and (2) introduce the student to a specific capability and/or limitation of CFD through hands-on practice. More templates are being developed that emphasize the first objective. The flow of fluid between two concentric rotating cylinders is a good example of a problem that is solved approximately, analytically, and with CFD, and the results are compared to enhance learning.

  14. The role of computational fluid dynamics (CFD) in hair science.

    Science.gov (United States)

    Spicka, Peter; Grald, Eric

    2004-01-01

    The use of computational fluid dynamics (CFD) as a virtual prototyping tool is widespread in the consumer packaged goods industry. CFD refers to the calculation on a computer of the velocity, pressure, and temperature and chemical species concentrations within a flowing liquid or gas. Because the performance of manufacturing equipment and product designs can be simulated on the computer, the benefit of using CFD is significant time and cost savings when compared to traditional physical testing methods. CFD has been used to design, scale-up and troubleshoot mixing tanks, spray dryers, heat exchangers and other process equipment. Recently, computer models of the capillary wicking process inside fibrous structures have been added to CFD software. These models have been used to gain a better understanding of the absorbent performance of diapers and feminine protection products. The same models can also be used to represent the movement of shampoo, conditioner, colorants and other products through the hair and scalp. In this paper, we provide an introduction to CFD and show some examples of its application to the manufacture of consumer products. We also provide sonic examples to show the potential of CFD for understanding the performance of products applied to the hair and scalp. PMID:15645102

  15. Reducing numerical costs for core wide nuclear reactor CFD simulations by the Coarse-Grid-CFD

    Science.gov (United States)

    Viellieber, Mathias; Class, Andreas G.

    2013-11-01

    Traditionally complete nuclear reactor core simulations are performed with subchannel analysis codes, that rely on experimental and empirical input. The Coarse-Grid-CFD (CGCFD) intends to replace the experimental or empirical input with CFD data. The reactor core consists of repetitive flow patterns, allowing the general approach of creating a parametrized model for one segment and composing many of those to obtain the entire reactor simulation. The method is based on a detailed and well-resolved CFD simulation of one representative segment. From this simulation we extract so-called parametrized volumetric forces which close, an otherwise strongly under resolved, coarsely-meshed model of a complete reactor setup. While the formulation so far accounts for forces created internally in the fluid others e.g. obstruction and flow deviation through spacers and wire wraps, still need to be accounted for if the geometric details are not represented in the coarse mesh. These are modelled with an Anisotropic Porosity Formulation (APF). This work focuses on the application of the CGCFD to a complete reactor core setup and the accomplishment of the parametrization of the volumetric forces.

  16. CFD research, parallel computation and aerodynamic optimization

    Science.gov (United States)

    Ryan, James S.

    1995-01-01

    Over five years of research in Computational Fluid Dynamics and its applications are covered in this report. Using CFD as an established tool, aerodynamic optimization on parallel architectures is explored. The objective of this work is to provide better tools to vehicle designers. Submarine design requires accurate force and moment calculations in flow with thick boundary layers and large separated vortices. Low noise production is critical, so flow into the propulsor region must be predicted accurately. The High Speed Civil Transport (HSCT) has been the subject of recent work. This vehicle is to be a passenger vehicle with the capability of cutting overseas flight times by more than half. A successful design must surpass the performance of comparable planes. Fuel economy, other operational costs, environmental impact, and range must all be improved substantially. For all these reasons, improved design tools are required, and these tools must eventually integrate optimization, external aerodynamics, propulsion, structures, heat transfer and other disciplines.

  17. FASTEF Heat exchanger tube rupture CFD simulation

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, V., E-mail: moreau@crs4.it [CRS4, Centre for Advanced Studies, Research and Development in Sardinia, Polaris, Edificio 1, 09010 Pula, CA (Italy)

    2012-11-15

    The aim of this technical note is to present CFD simulations of a tube rupture incidental scenario in a Primary Heat eXchanger (PHX)/Primary Pump (PP) assembly for two design variants of the FAst-Spectrum Transmutation Experimental Facility FASTEF ongoing design, in the framework of the FP7 Central Design Team (CDT) European project. The simulation domain reproduces with some simplification the entire primary coolant loop. The objective is to understand whether it is necessary take some counter-measures to avoid the ingress of steam in the cold plenum. The simulation has been performed on two successive updates of the design and of the nominal operation. The simulations show a good resistance to steam ingress, under the condition that provision is made to avoid an excessive accumulation of steam at the top of the PHX/PP assembly casing.

  18. CFD analysis of evaporation cooling experimental tests

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosini, W.; Forgione, N.; Mazzini, D.; Oriolo, F. [Pisa Univ., DIMNP (Italy); He, S. [British Energy Generation Ltd, Barnwood Gloucester (United Kingdom)

    2001-07-01

    Falling film evaporation cooling is investigated by a CFD (computational fluid dynamics) code. The experimental activity, carried out at the University of Pisa using the EFFE facility, is aimed to contribute to the understanding of the heat and mass transfer mechanisms involved in cooling of a metallic wall by evaporation of falling water films in a countercurrent air flow. This problem is relevant for innovative nuclear reactor containment. The mathematical model, the governing equations and the boundary conditions implemented in the code are briefly described; a detailed description of the method adopted to account for mass transfer and the presence of the film follows. Then, the calculated results are analysed and compared with experimental data, highlighting the improvement in the cooling capabilities obtained owing to evaporation with respect to the case of pure convection. (authors)

  19. CFD Analysis of Passive Autocatalytic Recombiner

    Directory of Open Access Journals (Sweden)

    B. Gera

    2011-01-01

    Full Text Available In water-cooled nuclear power reactors, significant quantities of hydrogen could be produced following a postulated loss-of-coolant accident (LOCA along with nonavailability of emergency core cooling system (ECCS. Passive autocatalytic recombiners (PAR are implemented in the containment of water-cooled power reactors to mitigate the risk of hydrogen combustion. In the presence of hydrogen with available oxygen, a catalytic reaction occurs spontaneously at the catalyst surfaces below conventional ignition concentration limits and temperature and even in presence of steam. Heat of reaction produces natural convection flow through the enclosure and promotes mixing in the containment. For the assessment of the PAR performance in terms of maximum temperature of catalyst surface and outlet hydrogen concentration an in-house 3D CFD model has been developed. The code has been used to study the mechanism of catalytic recombination and has been tested for two literature-quoted experiments.

  20. Improved Inlet Conditions for Terrain CFD

    DEFF Research Database (Denmark)

    Pedersen, Jesper Grønnegaard

    The atmospheric boundary layer flow over different types of terrain is studied through simulations made with the finite volume CFD code of Ellipsys 2D and 3D. The simulations are compared to measurements made at the Høvsøre test site and over the hill of Askervein.The primary objective of these...... describing the flow after a change in the surface roughness. The derivation of these expressions is based on a range of simulations of flows over flat terrain with different types of roughness changes.The derived expressions show good agreement with simulations and could, as intended, be used to define inlet...... conditions for flow simulations over terrain, where an upstream roughness change is thought to have an influence. More thorough experimental verification is however, thought necessary to make the expressions sufficiently reliable. The same goes for the simulations-based conclusions regarding the flow over...

  1. CFD simulation of mixing in anaerobic digesters.

    Science.gov (United States)

    Terashima, Mitsuharu; Goel, Rajeev; Komatsu, Kazuya; Yasui, Hidenari; Takahashi, Hiroshi; Li, Y Y; Noike, Tatsuya

    2009-04-01

    A three-dimensional CFD model incorporating the rheological properties of sludge was developed and applied to quantify mixing in a full-scale anaerobic digester. The results of the model were found to be in good agreement with experimental tracer response curve. In order to predict the dynamics of mixing, a new parameter, UI (uniformity index) was defined. The visual patterns of tracer mixing in simulation were well reflected in the dynamic variation in the value of UI. The developed model and methods were applied to determine the required time for complete mixing in a full-scale digester at different solid concentrations. This information on mixing time is considered to be useful in optimizing the feeding cycles for better digester performance. PMID:19081247

  2. REFRIGERAÇÃO UTILIZANDO PASTILHAS DE EFEITO PELTIER

    Directory of Open Access Journals (Sweden)

    Antonio Luiz P. S. Campos

    2010-06-01

    Full Text Available Pastilhas de Peltier são dispositivos baseados no efeito Peltier e são aplicadas para produzir efeito refrigerador ou aquecedor. Este trabalho aborda conceitos envolvidos na fabricação e funcionamento desses dispositivos tais como: histórico do efeito Peltier e desenvolvimento de placas de efeito Peltier. É feito um estudo de eficiência da refrigeração de água utilizando uma placa de efeito Peltier existente no Campus Natal – Zona Norte. Para isso, é implementada uma estrutura de refrigeração de água e são feitas medições para determinar a eficiência de sistema. Por fim, são apresentadas conclusões sobre o estudo desenvolvido.

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

    OpenAIRE

    Oliveira, Sara Maria de

    2013-01-01

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

  4. Application of Simple CFD Models in Smoke Ventilation Design

    DEFF Research Database (Denmark)

    Brohus, Henrik; Nielsen, Peter Vilhelm; la Cour-Harbo, Hans;

    2004-01-01

    The paper examines the possibilities of using simple CFD models in practical smoke ventilation design. The aim is to assess if it is possible with a reasonable accuracy to predict the behaviour of smoke transport in case of a fire. A CFD code mainly applicable for “ordinary” ventilation design...... uses a standard k-ε turbulence model. Simulations comprise both steady-state and dynamic approaches. Several boundary conditions are tested. Finally, the paper discusses the prospects of simple CFD models in smoke ventilation design including the inherent limitations....

  5. Applications of CFD in Hydraulics and River Engineering

    Science.gov (United States)

    Nguyen, Van Thinh; Nestmann, Franz

    2004-02-01

    In this paper, various applications and developments of CFD technology in hydraulics and river engineering are presented. Numerical studies of three-dimensional turbulent flow fields in open channels and rivers are carried out by CFD packages such as the finite element code FIDAP and finite volume code COMET. Meshing procedures are implemented by GAMBIT or CFD-GEOM. To calculate the position of the free surface two methods are applied, free surface tracking and volume-of-fluid, and some comparisons of these methods are discussed.

  6. Applications of CFD in hydraulics and river engineering

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, V.T.; Nestmann, F. [Univ. of Karlsruhe, Civil Engineering, Karlsruhe (Germany)]. E-mail: ge27@rz.uni-karlsruhe.de; Franz.Nestmann@iwk.uni-karlsruhe.de

    2002-07-01

    In this paper various applications and developments of CFD technology in hydraulics and river engineering are presented. Numerical studies of three dimensional turbulent flow fields in open channels and rivers are carried out by CFD packages such as finite element FIDAP of Fluent and finite volume COMET of ICCM (Institute of Computational Continuum Mechanics GmbH). Meshing procedures are implemented by GAMBIT (Fluent) or CFD-GEOM (CFDRC). Especially, to calculate the position of the free surface both methods, free surface tracking and Volume-Of-Fluid (VOF), are applied. (author)

  7. Wind Loads on Ships and Offshore Structures Estimated by CFD

    DEFF Research Database (Denmark)

    Aage, Christian; Hvid, S.L.; Hughes, P.H.;

    1997-01-01

    on a seagoing ferry and on a semisubmersible offshore platform have been estimated by CFD. The results have been compared with wind tunnel model tests and, for the ferry, a few full-scale measurements, and good agreement is obtained. The CFD method offers the possibility of a computational estimate of scale...... effects related to wind tunnel model testing. An example of such an estimate on the ferry is discussed. Due to the time involved in generating the computational mesh and in computing the solution, the CFD method is not at the moment economically competitive to routine wind tunnel model testing....

  8. MODELLING MANTLE TANKS FOR SDHW SYSTEMS USING PIV AND CFD

    DEFF Research Database (Denmark)

    Shah, Louise Jivan; Morrison, G.L.; Behnia, Masud

    1999-01-01

    Characteristics of vertical mantle heat exchanger tanks for SDHW systems have been investigated experimentally and theoretically using particle image velocimetry (PIV) and CFD modelling. A glass model of a mantle heat exchanger tank was constructed so that the flow distribution in the mantle could...... be studied using the PIV test facility. Two transient three-dimensional CFD-models of the glass model mantle tank were developed using the CFD-programmes CFX and FLUENT.The experimental results illustrate that the mantle flow structure in the mantle is complicated and the distribution of flow in the mantle...

  9. Variabilidad de estado trófico y la biomasa fitoplanctónica en Bahía Concepción, Golfo de California (1997-1999)

    OpenAIRE

    López Cortés, David J.; Gárate Lizárraga, Ismael; José J. Bustillos Guzmán; Alonso Rodríguez, Rosalba; Murillo Murillo, I.

    2003-01-01

    Con el propósito de determinar la variación de la biomasa del fitoplancton (clorofila a) y el estado trófico de Bahía Concepción ubicada en la parte central oeste del Golfo de California, se realizó un estudio hidro-biológico durante el período de 1997 a 1999. Se determinó la temperatura, la concentración del oxígeno disuelto y de nutrientes inorgánicos (nitrato, nitrito, fosfato y silicato), y la biomasa fitoplanctónica (clorofila a). Las condiciones hidrográficas muestran un período de mezc...

  10. CFD modeling of the IRIS pressurizer dynamic

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, Ronny R.; Montesinos, Maria E.; Garcia, Carlos; Bueno, Elizabeth D.; Mazaira, Leorlen R., E-mail: rsanz@instec.cu, E-mail: mmontesi@instec.cu, E-mail: cgh@instec.cu, E-mail: leored1984@gmail.com [Instituto Superior de Tecnologias y Ciencias Aplicadas (InSTEC), La Habana (Cuba); Bezerra, Jair L.; Lira, Carlos A.B. Oliveira, E-mail: jair.lima@ufpe.br, E-mail: cabol@ufpe.br [Universida Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear

    2015-07-01

    Integral layout of nuclear reactor IRIS makes possible the elimination of the spray system, which is usually used to mitigate in-surge transient and also help to Boron homogenization. The study of transients with deficiencies in the Boron homogenization in this technology is very important, because they can cause disturbances in the reactor power and insert a strong reactivity in the core. The detailed knowledge of the behavior of multiphase multicomponent flows is challenging due to the complex phenomena and interactions at the interface. In this context, the CFD modeling is employed in the design of equipment in the nuclear industry as it allows predicting accidents or predicting their performance in dissimilar applications. The aim of the present research is to model the IRIS pressurizer's dynamic using the commercial CFD code CFX. A symmetric tri dimensional model equivalent to 1/8 of the total geometry was adopted to reduce mesh size and minimize processing time. The model considers the coexistence of four phases and also takes into account the heat losses. The relationships for interfacial mass, energy, and momentum transport are programmed and incorporated into CFX. Moreover, two subdomains and several additional variables are defined to monitoring the boron dilution sequences and condensation-evaporation rates in different control volumes. For transient states a non - equilibrium stratification in the pressurizer is considered. This paper discusses the model developed and the behavior of the system for representative transients sequences. The results of analyzed transients of IRIS can be applied to the design of pressurizer internal structures and components. (author)

  11. CFD Analysis of Core Bypass Phenomena

    International Nuclear Information System (INIS)

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the one-twelfth grid can be set as a symmetry boundary

  12. CFD Analysis of Core Bypass Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

    2010-03-01

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the sector grid can be set as a symmetry boundary

  13. Bonneville Project: CFD of the Spillway Tailrace

    Energy Technology Data Exchange (ETDEWEB)

    Rakowski, Cynthia L.; Serkowski, John A.; Richmond, Marshall C.; Romero Gomez, Pedro DJ

    2012-11-19

    US Army Corps of Engineers, Portland District (CENWP) operates the Bonneville Lock and Dam Project on the Columbia River. High spill flows that occurred during 2011 moved a large volume of rock from downstream of the spillway apron to the stilling basin and apron. Although 400 cubic yards of rocks were removed from the stilling basin, there are still large volumes of rock downstream of the apron that could, under certain flow conditions, move upstream into the stilling basin. CENWP is investigating operational changes that could be implemented to minimize future movement of rock into the stilling basin. A key analysis tool to develop these operational changes is a computational fluid dynamics (CFD) model of the spillway. A free-surface CFD model of the Bonneville spillway tailrace was developed and applied for four flow scenarios. These scenarios looked at the impact of flow volume and flow distribution on tailrace hydraulics. The simulation results showed that areas of upstream flow existed near the river bed downstream of the apron, on the apron, and within the stilling basin for all flows. For spill flows of 300 kcfs, the cross-stream and downstream extent of the recirculation zones along Cascade and Bradford Island was very dependent on the spill pattern. The center-loaded pattern had much larger recirculation zones than the flat or bi-modal pattern. The lower flow (200 kcfs) with a flat pattern had a very large recirculation zone that extended half way across the channel near the river bed. A single flow scenario (300 kcfs of flow in a relatively flat spill pattern) was further interrogated using Lagrangian particle tracking. The tracked particles (with size and mass) showed the upstream movement of sediments onto the concrete apron and against the vertical wall between the apron and the stilling basin from seed locations downstream of the apron and on the apron.

  14. Bioadsorción de Cromo (VI en Solución Acuosa por la Biomasa Celular de Cryptococcus neoformans y Helminthosporium sp Biosorption of Chromium (VI from Aqueous Solutions by Fungal Biomass of Cryptococcus neoformans and Helminthosporium sp

    Directory of Open Access Journals (Sweden)

    I. Acosta

    2005-01-01

    Full Text Available Se determinó la bioadsorción de Cromo (VI en solución por la biomasa celular de la levadura capsulada Cryptococcus neoformans y del hongo micelial Helminthosporium sp, por el método colorimétrico de la difenilcarbazida. La biomasa de C. neoformans fue más eficiente en la remoción de Cromo (VI en solución (98% que la de Helminthosporium sp (65%. La mayor bioadsorción para C. neoformans fue a pH=2.0 +/- 0.2, mientras que para Helminthosporium sp fue a pH=4.0 +/- 0.2, ambas a 28oC durante 24 horas con 0.2 mg/L de biomasa celular. Se concluye que las biomasas fúngicas remueven eficientemente Cromo (VI en solución y pueden utilizarse para descontaminar nichos acuáticos contaminados con este metal.A determination was made on the biosorption of dissolved Chromium (VI using cellular biomass of the encapsulated yeast Cryptococcus neoformans and the mycelial fungus Helminthosporium sp. using a diphenylcarbazide colorimetric method. The C. neoformans biomass was more efficient in removing Chromium (VI from solution (98% than the Helminthosporium sp. (65%. The highest biosorption for C. neoformans was at pH 2.0 + 0.02, while for Helminthosporium sp this occurred at pH 4.0 + 0.2 , both at 28°C for 24 h employing 0.2 mg/L of cellular biomass. It is concluded that the fungal biomasses efficiently removed Chromium (VI from solution and could be used for decontamination of aquatic habitats polluted with this metal.

  15. Aprovechamiento de Biomasa Peletizada en el Sector Ladrillero en Bogotá-Colombia: Análisis Energético y Ambiental Use of Pelleted Biomass in the Brick Industry in Bogota-Colombia: Energy and Environmental Analysis

    Directory of Open Access Journals (Sweden)

    César A García-Ubaque

    2013-01-01

    Full Text Available En este estudio se compara el desempeño energético y ambiental del uso de combustibles a partir de dos tipos de biomasas peletizadas: residuos de madera, provenientes de podas y residuos de la producción de muebles, principalmente aserrín. La biomasa proveniente de residuos de madera es uno de los materiales más adecuados para utilizar como combustible alternativo. El sector ladrillero tiene una gran demanda energética para sus procesos de secado y cocción y el uso de combustibles alternativos a partir de biomasa permite obtener reducciones importantes en emisiones atmosféricas y no afecta las condiciones técnicas del proceso de producción de ladrillos. La biomasa con mejor desempeño, tanto en las variables energéticas como ambientales evaluadas, fue el aserrín.This study compared the energy and environmental performance of fuels from two types of pelleted biomass: wood waste from pruning and waste from furniture production, mainly sawdust. Wood residues biomass is one of the most suitable materials for using as an alternative fuel. The brick manufacture sector has a high energy demand for its drying and firing processes and the use of alternative fuels from biomass allows significant reductions in emissions and does not affect the technical conditions of the process of brick production. The biomass with better performance was sawdust, which presented the optimum energy and environmental variables.

  16. Cambios en el porcentaje de sodio intercambiable (PSI y la relación de absorción de sodio (RAS de un suelo y su influencia en la actividad y biomasa microbiana

    Directory of Open Access Journals (Sweden)

    Torrente Trujillo Armando

    2011-03-01

    Full Text Available

    Con el objetivo de evaluar los cambios en el PSI, la RAS y su influencia en la actividad y  biomasa  microbiana  del suelo,  se aplicaron  diversas  concentraciones  de vinaza  como enmienda procedente de la industria de alcohol carburante, sobre un suelo afectado por sodicidad con severas limitaciones en las condiciones físicas, químicas y biológicas. Se aplicó un diseño en bloques completos al azar que incluye cuatro tratamientos y tres repeticiones, y muestreos de suelo al inicio y final del proceso a tres profundidades (0-20, 20-40 y 40-60 cm, cuyas variables de respuesta a medir fueron  la respiración, C- biomasa microbiana, MO%, pH, CIC, CE, RAS y PSI. La actividad biológica (CO2 y el C-biomasa microbiana mostraron

    incrementos significativos en el rango ideal para el establecimento del cultivo de caña.

  17. Cambios en el porcentaje de sodio intercambiable (PSI y la relación de absorción de sodio (RAS de un suelo y su influencia en la actividad y biomasa microbiana

    Directory of Open Access Journals (Sweden)

    Cesar A Gasca

    2011-01-01

    Full Text Available Con el objetivo de evaluar los cambios en el PSI, la RAS y su influencia en la actividad y biomasa microbiana del suelo, se aplicaron diversas concentraciones de vinaza como enmienda procedente de la industria de alcohol carburante, sobre un suelo afectado por sodicidad con severas limitaciones en las condiciones físicas, químicas y biológicas. Se aplicó un diseño en bloques completos al azar que incluye cuatro tratamientos y tres repeticiones, y muestreos de suelo al inicio y final del proceso a tres profundidades (0-20, 20-40 y 40-60 cm, cuyas variables de respuesta a medir fueron la respiración, C- biomasa microbiana, MO%, pH, CIC, CE, RAS y PSI. La actividad biológica (CO2 y el C-biomasa microbiana mostraron incrementos significativos en el rango ideal para el establecimento del cultivo de caña.

  18. Equation for estimating tree biomass in tropical forests of Costa Rica Ecuación para estimar la biomasa arbórea en los bosques tropicales de Costa Rica

    Directory of Open Access Journals (Sweden)

    Shu Wei-Chou

    2013-06-01

    methodological approach to estimate forest biomass, which is very useful to support decision-making on carbon storage in tropical forests. Biomass determination in the field in future plots is going to help the calibration of this approach to estimate biomass stored in tropical forests.Una de las medidas más relevantes para la mitigación del cambio climático es la conservación y regeneración del bosque en nuestros países.  La cantidad de carbono que se almacena en la biomasa arbórea pasa a ser una medida relevante para la política pública. El presente trabajo analiza la asociación que tienen algunas variables dasométricas, fácilmente medibles, asociadas a la biomasa, con el propósito de estimarla indirectamente, dado que la medición directa de la biomasa arbórea es un trabajo complejo y tiene un costo muy elevado.  El objetivo general del estudio fue hacer un análisis del comportamiento de las variables dasométricas fácilmente medibles para predecir biomasa arbórea con datos de dos bosques tropicales de Costa Rica, con el propósito de analizar su posible aplicación generalizada en los bosques tropicales de todo el país. Mediante una revisión bibliográfica, se determinaron cuatro posibles modelos que estiman biomasa en bosques tropicales. Se evaluaron 907 árboles con diámetro a la altura de pecho (dap mayor a 10 cm en dos bosques tropicales de Costa Rica (Parque Nacional Corcovado en el suroeste y Fila Carbón en el sureste, vertiente del Caribe, generando una estimación de biomasa lo más precisa posible. Se realizó un análisis de las variables de los árboles (densidad específica de la madera, altura total y dap y su biomasa, con el fin de desarrollar el modelo que facilitara la predicción de esta. El modelo final utiliza como variables independientes el dap y la densidad.  Con el dap se da el hecho de que existe una alta correlación con la altura total, la cual es muy difícil de obtener en el campo, de modo que se decidió no utilizarla. La

  19. Uncovering MIT wind myths through micro-climatological CFD analysis

    CERN Document Server

    Kalmikov, Alexander

    2013-01-01

    Popular campus myths of unusually strong pedestrian level winds are investigated with a Computational Fluid Dynamics (CFD) approach. The numerical simulations confirm the existence of the reported phenomena and provide a qualitative explanation of their physical mechanisms.

  20. CFD Modeling of Free-Piston Stirling Engines

    Science.gov (United States)

    Ibrahim, Mounir B.; Zhang, Zhi-Guo; Tew, Roy C., Jr.; Gedeon, David; Simon, Terrence W.

    2001-01-01

    NASA Glenn Research Center (GRC) is funding Cleveland State University (CSU) to develop a reliable Computational Fluid Dynamics (CFD) code that can predict engine performance with the goal of significant improvements in accuracy when compared to one-dimensional (1-D) design code predictions. The funding also includes conducting code validation experiments at both the University of Minnesota (UMN) and CSU. In this paper a brief description of the work-in-progress is provided in the two areas (CFD and Experiments). Also, previous test results are compared with computational data obtained using (1) a 2-D CFD code obtained from Dr. Georg Scheuerer and further developed at CSU and (2) a multidimensional commercial code CFD-ACE+. The test data and computational results are for (1) a gas spring and (2) a single piston/cylinder with attached annular heat exchanger. The comparisons among the codes are discussed. The paper also discusses plans for conducting code validation experiments at CSU and UMN.

  1. Correlation of Puma airloads: Evaluation of CFD prediction methods

    Science.gov (United States)

    Strawn, Roger C.; Desopper, Andre; Miller, Judith; Jones, Alan

    1989-01-01

    A cooperative program was undertaken by research organizations in England, France, Australia and the U.S. to study the capabilities of computational fluid dynamics codes (CFD) to predict the aerodynamic loading on helicopter rotor blades. The program goal is to compare predictions with experimental data for flight tests of a research Puma helicopter with rectangular and swept tip blades. Two topics are studied. First, computed results from three CFD codes are compared for flight test cases where all three codes use the same partial inflow-angle boundary conditions. Second, one of the CFD codes (FPR) is iteratively coupled with the CAMRAD/JA helicopter performance code. These results are compared with experimental data and with an uncoupled CAMRAD/JA solution. The influence of flow field unsteadiness is found to play an important role in the blade aerodynamics. Alternate boundary conditions are suggested in order to properly model this unsteadiness in the CFD codes.

  2. Correlation of Puma airfoils - Evaluation of CFD prediction methods

    Science.gov (United States)

    Strawn, Roger C.; Desopper, Andre; Miller, Judith; Jones, Alan

    1989-01-01

    A cooperative program was undertaken by research organizations in England, France, Australia and the U.S. to study the capabilities of computational fluid dynamics codes (CFD) to predict the aerodynamic loading on helicopter rotor blades. The program goal is to compare predictions with experimental data for flight tests of a research Puma helicopter with rectangular and swept tip blades. Two topics are studied. First, computed results from three CFD codes are compared for flight test cases where all three codes use the same partial inflow-angle boundary conditions. Second, one of the CFD codes (FPR) is iteratively coupled with the CAMRAD/JA heilcopter performance code. These results are compared with experimental data and with an uncoupled CAMRAD/JA solution. The influence of flow field unsteadiness is found to play an important role in the blade aerodynamics. Alternate boundary conditions are suggested in order to properly model this unsteadiness in the CFD codes.

  3. A Multi-Physics CFD Toolkit for Reentry Flows Project

    Data.gov (United States)

    National Aeronautics and Space Administration — AeroSoft proposes to develop a full featured CFD toolkit for analysis of the aerothermal environment and its effect on space vehicles. In Phase I, AeroSoft proposes...

  4. CFD Simulation of the NREL Phase VI Rotor

    CERN Document Server

    Song, Yang

    2014-01-01

    The simulation of the turbulent and potentially separating flow around a rotating, twisted, and tapered airfoil is a challenging task for CFD simulations. This paper describes CFD simulations of the NREL Phase VI turbine that was experimentally characterized in the 24.4m x 36.6m NREL/NASA Ames wind tunnel (Hand et al., 2001). All computations in this article are performed on the experimental base configuration of 0o yaw angle, 3o tip pitch angle, and a rotation rate of 72 rpm. The significance of specific mesh resolution regions to the accuracy of the CFD prediction is discussed. The ability of CFD to capture bulk quantities, such as the shaft torque, and the detailed flow characteristics, such as the surface pressure distributions, are explored for different inlet wind speeds. Finally, the significant three-dimensionality of the boundary layer flow is demonstrated.

  5. CFD studies of mass transfer performance in pulsed column

    International Nuclear Information System (INIS)

    A tracer injection technique was used to study the mass transfer characteristics of aqueous phase in the Φ 38 mm pulsed sieve extraction column. A computational fluid dynamics (CFD) model has been developed to simulation the mass transfer process of the tracer. The residence time distribution of the tracer which get from CFD simulation were used to fitting the aqueous phase axial dispersion coefficient. The experiment results were in consistence with the simulation results; The simulation results show that the concentration of tracer change with pulsed velocity; The axial dispersion co efficient fitting by CFD model was Similar with published data. The presented CFD predictions and validation with experimental data will provide a possible ways to eliminate experiments and will contribute to better understanding of the hydrodynamics in extraction columns. (authors)

  6. CFD modelling of Stirling engines with complex design topologies

    OpenAIRE

    Alexakis, Thanos

    2013-01-01

    This research is in the field of CFD modelling of heat engines, particularly the advanced CFD methodologies for the performance characterization of solar Stirling Engines with complex geometrical topologies. The research aims to investigate whether these methods can provide a more inclusive picture of the engine performance and how this information can be used for the design improvement of Stirling engines and the investigation of more complex engine topologies.

  7. Methods of fluid properties for compressible refrigerant CFD analysis

    OpenAIRE

    Branch, Scott

    2014-01-01

    There are numerous ways of defining fluids properties for computational fluid dynamic (CFD) simulations. This paper examines three methods of defining fluid properties that are available in a commercial CFD code. Simulations were carried out for an R410a scroll compressor used in air conditioning applications and the effects are illustrated through the compression process. The first method used is the real gas property data from the National Institute of Standards and Technology (NIST). While...

  8. Application of CFD Code PHOENICS for simulating CYCLONE SEPARATORS

    International Nuclear Information System (INIS)

    The work presents a computational fluid dynamics (CFD) calculation to investigate the flow field in a tangential inlet cyclone which is mainly used for the separation of the moisture from an air stream. Three-dimensional, steady state Eulerian simulations of the turbulent gas - droplet flow in a cyclone separator have been performed. Numerical simulation was carried out using CFD code PHOENICS for the given geometry of separators available in literature

  9. CFD Technology for Rotorcraft Gearbox Windage Aerodynamics Simulation

    Science.gov (United States)

    Handschuh, Robert; Hill, Matthew; Kunz, Robert; Long, Lyle; Morris, Philip; Noack, Ralph

    2009-01-01

    A computational fluid dynamics (CFD) method is adapted, validated and applied to spinning gear systems with emphasis on predicting windage losses. Several spur gears and a disc are studied. The CFD simulations return good agreement with measured windage power loss. Turbulence modeling choices, the relative importance of viscous and pressure torques with gear speed and the physics of the complex 3-D unsteady flow field in the vicinity of the gear teeth are studied.

  10. CFD simulation of nuclear graphite oxidation / P. Sukdeo.

    OpenAIRE

    Sukdeo, Preeyanand

    2010-01-01

    This study investigates the development of a strategy to simulate nuclear graphite oxidation with Computational Fluid Dynamics (CFD) to determine an estimate of graphite lost. The task was achieved by comparing the results of the CFD approach with a number of different experiments. For molecular diffusion, simulated results were compared to analytical solutions. Mass flow rates under conditions of natural convection were sourced from the 2002 NACOK experiment. Experimental data...

  11. CFD simulation of nanofiber-enhanced air filter media

    OpenAIRE

    Tronville, Paolo Maria

    2015-01-01

    The first step in a CFD analysis of filter media flow is to create a computational domain geometry which imitates the simulated media as closely as is practical. The media in the present study combined a relatively flat web of nanofibers with a cellulosic fiber support media. A CFD grid suited to calculating the flow patterns through the cellulosic media structure would be far too coarse to simulate flow around the nanofiber web elements. This scale difference forces some assumption about the...

  12. Feasibility of patient specific aortic blood flow CFD simulation.

    Science.gov (United States)

    Svensson, Johan; Gårdhagen, Roland; Heiberg, Einar; Ebbers, Tino; Loyd, Dan; Länne, Toste; Karlsson, Matts

    2006-01-01

    Patient specific modelling of the blood flow through the human aorta is performed using computational fluid dynamics (CFD) and magnetic resonance imaging (MRI). Velocity patterns are compared between computer simulations and measurements. The workflow includes several steps: MRI measurement to obtain both geometry and velocity, an automatic levelset segmentation followed by meshing of the geometrical model and CFD setup to perform the simulations follwed by the actual simulations. The computational results agree well with the measured data. PMID:17354898

  13. Case studies from the REHVA CFD guide book

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    2008-01-01

    This paper presents CFD predictions which are used at different levels, from the evaluation of an idea to the design of a system, or for the analysing work on an existing building.......This paper presents CFD predictions which are used at different levels, from the evaluation of an idea to the design of a system, or for the analysing work on an existing building....

  14. A computational design system for rapid CFD analysis

    Science.gov (United States)

    Ascoli, E. P.; Barson, S. L.; Decroix, M. E.; Sindir, Munir M.

    1992-01-01

    A computation design system (CDS) is described in which these tools are integrated in a modular fashion. This CDS ties together four key areas of computational analysis: description of geometry; grid generation; computational codes; and postprocessing. Integration of improved computational fluid dynamics (CFD) analysis tools through integration with the CDS has made a significant positive impact in the use of CFD for engineering design problems. Complex geometries are now analyzed on a frequent basis and with greater ease.

  15. Efecto de fertilización nitrogenada en la producción de biomasa y calidad de aceite esencial en Lippia alba (Miller, Pronto alivio.

    Directory of Open Access Journals (Sweden)

    Sánchez O. M.

    2004-04-01

    Full Text Available En el Campo Experimental de la Universidad Nacional de Colombia sede Palmira (CEUNP se realizó un ensayo para evaluar el efecto de la fertilización nitrogenada, aplicando dos fuentes (gallinaza y urea en dos niveles (50 y 100 kg/ha de nitrógeno y dos frecuencias de corte (dos y cuatro meses. En el lote experimental se situaron 15 parcelas, en un diseño de bloques completos al azar, con cinco tratamientos y tres repeticiones. Para el análisis de la información se utilizó el programa estadístico SAS. El máximo rendimiento de biomasa y aceites esenciales se obtuvo con la aplicación de 100 kg/ha de nitrógeno en forma de urea y la frecuencia de corte cada dos meses. Los niveles de extracción de Lippia alba en nitrógeno variaron entre 79.7 y 128.5; fósforo entre 24.5 y 30.5; potasio entre 114.6 y 138.8 y calcio entre 100 y 150 kg/ha. El aceite esencial estuvo compuesto mayoritariamente por carvona y limoneno. Palabras claves: Fertilización nitrogenada, Lippia alba, Rendimientos biomasa, aceites esenciales, pronto alivio. ABSTRACT Nitrogenous fertilization effects in the Lippia alba production and quality. In the Experimental Center of the National University of Colombia-Palmira (CEUNP a experiment was realized to evaluate the effect of the nitrogenous fertilization, using two sources (gallinaza and urea at two levels (50 and 100 kg/ha of nitrogen and two cutting frequencies (each two and four months. In the experimental area 15 plots were planted, in a randomized Complete Blocks design random (RCBD with five treatments and three repetitions to measure the following variables: production of fresh matter, content of dry matter, nutrients extraction and content of essential oils. The analysis of variance used the statistical program SAS. The maximum yield of biomass and essential was obtained oils combining the fertilization with 100 kg/ha of nitrogen as urea and the cutting frequency every of two months. The levels of nutrients

  16. A CFD/CSD Interaction Methodology for Aircraft Wings

    Science.gov (United States)

    Bhardwaj, Manoj K.

    1997-01-01

    With advanced subsonic transports and military aircraft operating in the transonic regime, it is becoming important to determine the effects of the coupling between aerodynamic loads and elastic forces. Since aeroelastic effects can contribute significantly to the design of these aircraft, there is a strong need in the aerospace industry to predict these aero-structure interactions computationally. To perform static aeroelastic analysis in the transonic regime, high fidelity computational fluid dynamics (CFD) analysis tools must be used in conjunction with high fidelity computational structural fluid dynamics (CSD) analysis tools due to the nonlinear behavior of the aerodynamics in the transonic regime. There is also a need to be able to use a wide variety of CFD and CSD tools to predict these aeroelastic effects in the transonic regime. Because source codes are not always available, it is necessary to couple the CFD and CSD codes without alteration of the source codes. In this study, an aeroelastic coupling procedure is developed which will perform static aeroelastic analysis using any CFD and CSD code with little code integration. The aeroelastic coupling procedure is demonstrated on an F/A-18 Stabilator using NASTD (an in-house McDonnell Douglas CFD code) and NASTRAN. In addition, the Aeroelastic Research Wing (ARW-2) is used for demonstration of the aeroelastic coupling procedure by using ENSAERO (NASA Ames Research Center CFD code) and a finite element wing-box code (developed as part of this research).

  17. CFD Parametric Study of Consortium Impeller

    Science.gov (United States)

    Cheng, Gary C.; Chen, Y. S.; Garcia, Roberto; Williams, Robert W.

    1993-01-01

    Current design of high performance turbopumps for rocket engines requires effective and robust analytical tools to provide design impact in a productive manner. The main goal of this study is to develop a robust and effective computational fluid dynamics (CFD) pump model for general turbopump design and analysis applications. A Finite Difference Navier-Stokes flow solver, FDNS, which includes the extended k-epsilon turbulence model and appropriate moving interface boundary conditions, was developed to analyze turbulent flows in turbomachinery devices. A second-order central difference scheme plus adaptive dissipation terms was employed in the FDNS code, along with a predictor plus multi-corrector pressure-based solution procedure. The multi-zone, multi-block capability allows the FDNS code to efficiently solve flow fields with complicated geometry. The FDNS code has been benchmarked by analyzing the pump consortium inducer, and it provided satisfactory results. In the present study, a CFD parametric study of the pump consortium impeller was conducted using the FDNS code. The pump consortium impeller, with partial blades, is a new design concept of the advanced rocket engines. The parametric study was to analyze the baseline design of the consortium impeller and its modification which utilizes TANDEM blades. In the present study, the TANDEM blade configuration of the consortium impeller considers cut full blades for about one quarter chord length from the leading edge and clocks the leading edge portion with an angle of 7.5 or 22.5 degrees. The purpose of the present study is to investigate the effect and trend of the TANDEM blade modification and provide the result as a design guideline. A 3-D flow analysis, with a 103 x 23 x 30 mesh grid system and with the inlet flow conditions measured by Rocketdyne, was performed for the baseline consortium impeller. The numerical result shows that the mass flow rate splits through various blade passages are relatively uniform

  18. CFD for Subcooled Flow Boiling: Parametric Variations

    Directory of Open Access Journals (Sweden)

    Roland Rzehak

    2013-01-01

    Full Text Available We investigate the present capabilities of CFD for wall boiling. The computational model used combines the Euler/Euler two-phase flow description with heat flux partitioning. Very similar modeling was previously applied to boiling water under high pressure conditions relevant to nuclear power systems. Similar conditions in terms of the relevant nondimensional numbers have been realized in the DEBORA tests using dichlorodifluoromethane (R12 as the working fluid. This facilitated measurements of radial profiles for gas volume fraction, gas velocity, liquid temperature, and bubble size. Robust predictive capabilities of the modeling require that it is validated for a wide range of parameters. It is known that a careful calibration of correlations used in the wall boiling model is necessary to obtain agreement with the measured data. We here consider tests under a variety of conditions concerning liquid subcooling, flow rate, and heat flux. It is investigated to which extent a set of calibrated model parameters suffices to cover at least a certain parameter range.

  19. SSME HPOTP impeller backcavity CFD analysis

    Science.gov (United States)

    Hsu, W. W.; Lin, S. J.

    1992-01-01

    The ball bearings behind the Space Shuttle Main Engine (SSME) HPOTP preburner pump have a history of premature wear requiring their replacement. Extensive tests have been conducted in an attempt to identify the operating factors that contribute to the wear. It has been conjectured that the coolant inflow velocity swirl pattern can aid bearing operation by matching ball orbit speed and thus affect bearing life. However, control of the velocity distribution up to now could only be achieved by trial and error following hardware testing. Observation of hardware from recent flight and development operation led to the hypothesis that certain assemblies with more extensive grinding patterns on the backwall of the impeller for rotor balancing correlated with improved bearing wear. To analytically evaluate the effect of cavity configuration on the flowfield, 3-D computational fluid dynamics (CFD) analyses of various geometries was successfully executed using REACT3D. Height of the anti-vortex ribs on the stationary wall was varied, as was the configuration of the rotating wall, from smooth to simulations of various grindout patterns. The results obtained indicate the effects of the various geometries and provide valuable guidelines for cavity modification to optimize bearing cooling.

  20. CFD modeling of passive autocatalytic recombiners*

    Directory of Open Access Journals (Sweden)

    Orszulik Magdalena

    2015-06-01

    Full Text Available This study deals with numerical modeling of passive autocatalytic hydrogen recombiners (PARs. Such devices are installed within containments of many nuclear reactors in order to remove hydrogen and convert it to steam. The main purpose of this work is to develop a numerical model of passive autocatalytic recombiner (PAR using the commercial computational fluid dynamics (CFD software ANSYS-FLUENT and tuning the model using experimental results. The REKO 3 experiment was used for this purpose. Experiment was made in the Institute for Safety Research and Reactor Technology in Julich (Germany. It has been performed for different hydrogen concentrations, different flow rates, the presence of steam, and different initial temperatures of the inlet mixture. The model of this experimental recombiner was elaborated within the framework of this work. The influence of mesh, gas thermal conductivity coefficient, mass diffusivity coefficients, and turbulence model was investigated. The best results with a good agreement with REKO 3 data were received for k-ɛ model of turbulence, gas thermal conductivity dependent on the temperature and mass diffusivity coefficients taken from CHEMKIN program. The validated model of the PAR was next implemented into simple two-dimensional simulations of hydrogen behavior within a subcompartment of a containment building.

  1. CFD simulation of pulse combustion's performance

    Science.gov (United States)

    Rahmatika, Annie Mufyda; Widiyastuti, W.; Winardi, Sugeng; Nurtono, Tantular; Machmudah, Siti; Kusdianto, Joni, I. Made

    2016-02-01

    This study aims to show changes in the performance of combustion using pulse combustion at specified intervals using simulation. Simulations is performed using Computational Fluid Dynamics analysis (CFD) software Ansys Fluent 15.0. Analysis used 2D illustration axisymmetric with k-ɛ turbulence models. Propane was selected as fuel at a flow rate of 15 L/min. Air with flow rate of 375 L/min is used as oxidizer. To investigate the advantages of using pulse combustion, the simulated pulse combustion is compared to normal combustion without a pulse. This is done by displaying descriptions of the phenomenon, mechanisms and results output gas combustor. From the analysis of simulation results showed that in 1 minute burning time, burning fuel without requiring pulse as much as 15 L while the pulse combustion requires half of the fuel which is 12.5 L. However, the higher average of temperature was generated by pulse combustion and the amounts of unburned fuel that comes out of the combustor less than without the use of pulse combustion. So, it can be concluded that the pulse combustion is more efficient than combustion without a pulse.

  2. Utilizing GPUs to Accelerate Turbomachinery CFD Codes

    Science.gov (United States)

    MacCalla, Weylin; Kulkarni, Sameer

    2016-01-01

    GPU computing has established itself as a way to accelerate parallel codes in the high performance computing world. This work focuses on speeding up APNASA, a legacy CFD code used at NASA Glenn Research Center, while also drawing conclusions about the nature of GPU computing and the requirements to make GPGPU worthwhile on legacy codes. Rewriting and restructuring of the source code was avoided to limit the introduction of new bugs. The code was profiled and investigated for parallelization potential, then OpenACC directives were used to indicate parallel parts of the code. The use of OpenACC directives was not able to reduce the runtime of APNASA on either the NVIDIA Tesla discrete graphics card, or the AMD accelerated processing unit. Additionally, it was found that in order to justify the use of GPGPU, the amount of parallel work being done within a kernel would have to greatly exceed the work being done by any one portion of the APNASA code. It was determined that in order for an application like APNASA to be accelerated on the GPU, it should not be modular in nature, and the parallel portions of the code must contain a large portion of the code's computation time.

  3. CFD and FEM modeling of PPOOLEX experiments

    Energy Technology Data Exchange (ETDEWEB)

    Paettikangas, T.; Niemi, J.; Timperi, A. (VTT Technical Research Centre of Finland (Finland))

    2011-01-15

    Large-break LOCA experiment performed with the PPOOLEX experimental facility is analysed with CFD calculations. Simulation of the first 100 seconds of the experiment is performed by using the Euler-Euler two-phase model of FLUENT 6.3. In wall condensation, the condensing water forms a film layer on the wall surface, which is modelled by mass transfer from the gas phase to the liquid water phase in the near-wall grid cell. The direct-contact condensation in the wetwell is modelled with simple correlations. The wall condensation and direct-contact condensation models are implemented with user-defined functions in FLUENT. Fluid-Structure Interaction (FSI) calculations of the PPOOLEX experiments and of a realistic BWR containment are also presented. Two-way coupled FSI calculations of the experiments have been numerically unstable with explicit coupling. A linear perturbation method is therefore used for preventing the numerical instability. The method is first validated against numerical data and against the PPOOLEX experiments. Preliminary FSI calculations are then performed for a realistic BWR containment by modeling a sector of the containment and one blowdown pipe. For the BWR containment, one- and two-way coupled calculations as well as calculations with LPM are carried out. (Author)

  4. Secuestro de carbono en la biomasa aérea de un sistema agrosilvopastoril de Cocos nucifera, Leucaena leucocephala Var. Cunningham y Pennisetum purpureum Cuba CT-115

    Directory of Open Access Journals (Sweden)

    J. M. Anguiano

    2013-01-01

    Full Text Available Con el objetivo de estimar el secuestro de carbono en la biomasa aérea de un sistema agrosilvopastoril (sasp compuesto por cocotero (Cocos nucifera, Leucaena leucocephala Var. Cunningham sembrada en alta densidad y Pennisetum purpureum Cuba CT-115, se llevó a cabo un estudio en un suelo con textura franco arcillo- arenosa. Se utilizó un diseño en bloques al azar con arreglo en parcelas divididas con cuatro tratamientos 0, 40, 60 y 80 mil árboles de leucaena ha-1 y tres repeticiones; la evaluación duró desde su establecimiento hasta 340 días de edad. Los resultados muestran diferencia estadística (P<0.001 en el secuestro de carbono con 101.19d, 109.73c, 122.00b y 128.62a t C+ha-1año-1 para los sasp de 0, 40, 60 y 80 mil plantas de leucaena ha-1, respectivamente. El mayor aporte de secuestro de carbono lo realizó el cocotero que aportó del 60 al 80% del total del sasp y existió una relación inversa de secuestro de carbono de la gramínea al incrementar la densidad de la leguminosa. El tratamiento que incorpora la siembra en alta densidad de la leguminosa arbórea logró un mayor secuestro de carbono.

  5. EFECTO DEL ÁCIDO SALICÍLICO EN EL CRECIMIENTO DE LA RAÍZ Y BIOMASA TOTAL DE PLÁNTULAS DE TRIGO

    Directory of Open Access Journals (Sweden)

    Cesar J. Tucuch Haas

    2015-03-01

    Full Text Available Se reportan los resultados de dos experimentos independientes para evaluar el efecto del ácido salicílico (AS en plántulas de trigo (Triticum aestivum L.. Las plántulas de ambos experimentos se germinaron y crecieron en agrolita contenida en tubos de PVC y en condiciones de cielo abierto bajo un diseño experimental completamente al azar con 8 repeticiones por tratamiento, las plántulas se asperjaron durante 5 días con 1 y 0.1 µM de AS o agua como control. Diez días después fueron cosechadas y realizadas las mediciones. Los resultados señalan que el AS favoreció significativamente el peso fresco de la raíz, así como la altura y el peso fresco de la biomasa total, en comparación con el control. El mejor tratamiento para estimular el crecimiento de plántulas de trigo fue el de 1µM de AS.

  6. Abundancia y biomasa de macroinvertebrados edáficos en la temporada lluviosa, en tres usos de la tierra, en los Andes colombianos

    Directory of Open Access Journals (Sweden)

    Pardo Luis C

    2006-03-01

    Full Text Available COMPENDIO los usos evaluados fueron pastizal, cafetal y bosque secundario (Vereda Villa del Rosario, Aprox. 3º 33' 16â€? Latitud Norte y 76º 36' 01â€? Longitud Oeste, altitud 1.500 a 1.820m., precipitación 960 a 1.050 mm/año, 19.8 a 21.2º C con la metodología TSBF. Se implementaron tres monolitos por uso y cada uno se subdividió en cuatro estratos (hojarasca, 0-10 cm, 10-20 cm, y 20-30 cm, las variables densidad y biomasa por parcela y estrato se examinaron a través de ANOVAS y Post-Anovas. En abundancia la supremacía fue de hormigas (25584 ejemplares, miriápodos (4808 ejemplares y lombrices (1984 ejemplares, la diferencia significativa la marcaron los miriápodos (F=4.84, P=0.014 asociados con bosque y cafetal con sombrío. En biomasa los grupos más importantes fueron miriápodos (701.05 g m-2, 58.71%, lombrices (90.64 g m-2; 7.59%, chisas (27.07 g m-2; 2.26% hor­migas (20.90 g m-2; 1.75% y arañas (15.71 g m-2 ; 1.31%, con diferencias significativas en hormigas (F=4.17, P=0.024 y arañas (F=3.43, P=0.4024; También hubo diferencias estadísticas significativas en la densidad y biomasa de macroinvertebrados y los estratos de los monolitos, los resultados indican que estos organismos expresan en su población y biomasa respuestas ambientales asociadas más con la estructura del agroecosistema que con la variación química, física o microbiológica del hábitat; se recomienda discriminar taxonómicamente los grupos funcionales y ampliar los muestreos a la temporada seca. Palabras clave: uso del suelo, macroinvertebrados edáficos, densidad, abundancia, agroecosistemas, Andes colombianos. ABSTRACT Abundance and biomass of soil macroinvertabrates during the rainy season in three land use systems in the Colombian Andes. Using the TSBF methodology, three land use systems—pastures, coffee plantation, and secondary forest— were evaluated in the rural community of Villa del Rosario, located in the

  7. LA BIOMASA COMO ALTERNATIVA AL PETRÓLEO PARA LA OBTENCIÓN DE PRODUCTOS QUÍMICOS: ACETONA Y ETANOL COMO MOLÉCULAS PLATAFORMA

    Directory of Open Access Journals (Sweden)

    Jorge Quesada

    2014-01-01

    Full Text Available En este trabajo se pretende reflejar el potencial de la biomasa como materia prima para la obtención de productos químicos de elevado valor añadido, integrando su viabilidad económica y técnica dentro del concepto de biorefinería. Considerando el gran número de trabajos existentes acerca de la obtención de biocombustibles, se hace hincapié en el aprovechamiento de los subproductos de estos procesos, abordando la transformación de dos de las moléculas plataforma de mayor proyección: el etanol y la acetona. Si bien gran parte de los procesos químicos que se exponen no son novedosos, la necesidad de sustituir el petróleo por una materia prima renovable ha impulsado de nuevo su estudio y la optimización de los parámetros que actualmente limitan su implantación en la industria, desarrollando nuevos catalizadores y estudiando la influencia de diferentes condiciones de reacción.

  8. Application perspectives of simulation techniques CFD in nuclear power plants

    International Nuclear Information System (INIS)

    The scenarios simulation in nuclear power plants is usually carried out with system codes that are based on concentrated parameters networks. However situations exist in some components where the flow is predominantly 3-D, as they are the natural circulation, mixed and stratification phenomena. The simulation techniques of computational fluid dynamics (CFD) have the potential to simulate these flows numerically. The use of CFD simulations embraces many branches of the engineering and continues growing, however, in relation to its application with respect to the problems related with the safety in nuclear power plants, has a smaller development, although is accelerating quickly and is expected that in the future they play a more emphasized paper in the analyses. A main obstacle to be able to achieve a general acceptance of the CFD is that the simulations should have very complete validation studies, sometimes not available. In this article a general panorama of the state of the methods application CFD in nuclear power plants is presented and the problem associated to its routine application and acceptance, including the view point of the regulatory authorities. Application examples are revised in those that the CFD offers real benefits and are also presented two illustrative study cases of the application of CFD techniques. The case of a water recipient with a heat source in its interior, similar to spent fuel pool of a nuclear power plant is presented firstly; and later the case of the Boron dilution of a water volume that enters to a nuclear reactor is presented. We can conclude that the CFD technology represents a very important opportunity to improve the phenomena understanding with a strong component 3-D and to contribute in the uncertainty reduction. (Author)

  9. A new methodology for the CFD uncertainty analysis

    Institute of Scientific and Technical Information of China (English)

    YAO Zhen-qiu; SHEN Hong-cui; GAO Hui

    2013-01-01

    With respect to the measurement uncertainty,this paper discusses the definition,the sources,the classification and the expressions of the CFD uncertainty.Based on the orthogonal design and the statistics inference theory,a new verification and validation method and the related procedures in the CFD simulation are developed.With the method,two examples of the CFD verification and validation are studied for the drag coefficient and the nominal wake fraction,and the calculation factors and their interactions which would significantly affect the simulation results are obtained.Moreover,the sizes of all uncertainty components resulting from the controlled and un-controlled calculation factors are determined,and the optimal combination of the calculation factors is obtained by an effect estimation in the orthogonal experiment design.It is shown that the new method can be used for the verification in the CFD uncertainty analysis,and can reasonably and definitely judge the credibility of the simulative result.As for CFD simulation of the drag coefficient and the nominal wake fraction,the results predicted can be validated.Although there is still some difference between the simulation results and the experiment results,its approximate level and credibility can be accepted.

  10. CFD simulation of flow through heart: a perspective review.

    Science.gov (United States)

    Khalafvand, S S; Ng, E Y K; Zhong, L

    2011-01-01

    The heart is an organ which pumps blood around the body by contraction of muscular wall. There is a coupled system in the heart containing the motion of wall and the motion of blood fluid; both motions must be computed simultaneously, which make biological computational fluid dynamics (CFD) difficult. The wall of the heart is not rigid and hence proper boundary conditions are essential for CFD modelling. Fluid-wall interaction is very important for real CFD modelling. There are many assumptions for CFD simulation of the heart that make it far from a real model. A realistic fluid-structure interaction modelling the structure by the finite element method and the fluid flow by CFD use more realistic coupling algorithms. This type of method is very powerful to solve the complex properties of the cardiac structure and the sensitive interaction of fluid and structure. The final goal of heart modelling is to simulate the total heart function by integrating cardiac anatomy, electrical activation, mechanics, metabolism and fluid mechanics together, as in the computational framework. PMID:21271418

  11. CFD based extraction column design-Chances and challenges

    Institute of Scientific and Technical Information of China (English)

    Mark W Hlawitschka; Menwer M Attarakih; Samer S Alzyod; Hans-Jrg Bart

    2016-01-01

    This paper shows that one-dimensional (1-D) [and three-dimensional (3-D) computational fluid dynamics (CFD)] simulations can replace the state-of-the-art usage of pseudo-homogeneous dispersion or back mixing models. This is based on standardized lab-scale cel experiments for the determination of droplet rise, breakage, coalescence and mass transfer parameters in addition to a limited number of additional mini-plant experiments with original fluids. Alternatively, the hydrodynamic parameters can also be derived using more sophisticated 3-D CFD simulations. Computational 1-D modeling served as a basis to replace pilot-plant experiments in any column geometry. The combination of 3-D CFD simulations with droplet population balance models (DPBM) increased the accuracy of the hydrodynamic simulations and gave information about the local droplet size. The high computational costs can be reduced by open source CFD codes when using a flexible mesh generation. First combined simulations using a three way coupled CFD/DPBM/mass-transfer solver pave the way for a safer design of industrial-sized columns, where no correlations are available.

  12. Fuel assembly simulations using LRGR-CFD and CGCFD

    International Nuclear Information System (INIS)

    In addition to the traditional fuel assembly simulation approaches using system codes, subchannel codes or porous medium approaches, as well as detailed CFD simulations to analyze single sub channels, a Low Resolution Geometry Resolving (LRGR) CFD approach and a Coarse-Grid-CFD (CGCFD) approach is taken. Both methods are based on a low resolution mesh that allows the capture of large and medium scale flow features such as recirculation zones, which cannot be reproduced by the system codes, subchannel codes and porous media approaches. The LRGR approach allows for instance fine-tuning the porous parameters which are important input for a porous medium approach. However, it should be noted that the prediction of detailed flow features such as secondary flows is not feasible. Using this approach, the consequences of flow blockages for detection possibilities and cladding temperatures can be discussed. Within the Coarse-Grid CFD approach a subgrid model (SGM) accounts for sub grid volumetric forces which are derived from validated CFD simulations. The volumetric forces take account of the non resolved physics due to the coarse mesh. The CGCFD approach with SGM can be applied to simulate complete fuel assemblies or even complete cores capturing the unique features of the complex flow induced by the fuel assembly geometry and its spacers. In such a case, grids with a very low grid resolution are employed. The current paper discusses and presents both, the CGCFD and the LRGR approaches. (author)

  13. Study of indoor radon distribution using measurements and CFD modeling

    International Nuclear Information System (INIS)

    Measurement and/or prediction of indoor radon (222Rn) concentration are important due to the impact of radon on indoor air quality and consequent inhalation hazard. In recent times, computational fluid dynamics (CFD) based modeling has become the cost effective replacement of experimental methods for the prediction and visualization of indoor pollutant distribution. The aim of this study is to implement CFD based modeling for studying indoor radon gas distribution. This study focuses on comparison of experimentally measured and CFD modeling predicted spatial distribution of radon concentration for a model test room. The key inputs for simulation viz. radon exhalation rate and ventilation rate were measured as a part of this study. Validation experiments were performed by measuring radon concentration at different locations of test room using active (continuous radon monitor) and passive (pin-hole dosimeters) techniques. Modeling predictions have been found to be reasonably matching with the measurement results. The validated model can be used to understand and study factors affecting indoor radon distribution for more realistic indoor environment. - Highlights: • Indoor radon distribution has been studied using active and passive measurements and CFD simulation. • At low ventilation, non-uniformity of radon concentration was observed. • Measured wall radon flux and ventilation rate has been used in simulations. • CFD simulation results were found to be close to measurements

  14. CFD modeling of a boiler's tubes rupture

    International Nuclear Information System (INIS)

    This paper reports the results of a study on the reason for tubes damage in the superheater Platen section of the 320 MW Bisotoun power plant, Iran. The boiler has three types of superheater tubes and the damage occurs in a series of elbows belongs to the long tubes. A three-dimensional modeling was performed using an in-house computational fluid dynamics (CFD) code in order to explore the reason. The code has ability of simultaneous solving of the continuity, the Reynolds-Averaged Navier-Stokes (RANS) equations and employing the turbulence, combustion and radiation models. The whole boiler including; walls, burners, air channels, three types of tubes, etc., was modeled in the real scale. The boiler was meshed into almost 2,000,000 tetrahedral control volumes and the standard k-ε turbulence model and the Rosseland radiation model were used in the model. The theoretical results showed that the inlet 18.9 MPa saturated steam becomes superheated inside the tubes and exit at a pressure of 17.8 MPa. The predicted results showed that the temperature of the steam and tube's wall in the long tubes is higher than the short and medium size tubes. In addition, the predicted steam mass flow rate in the long tube was lower than other ones. Therefore, it was concluded that the main reason for the rupture in the long tubes elbow is changing of the tube's metal microstructure due to working in a temperature higher than the design temperature. In addition, the structural fatigue tension makes the last elbow of the long tube more ready for rupture in comparison with the other places. The concluded result was validated by observations from the photomicrograph of the tube's metal samples taken from the damaged and undamaged sections

  15. CFD model of an aerating hydrofoil

    International Nuclear Information System (INIS)

    Improving water quality in the tailrace below hydroelectric dams has become a priority in many river systems. In warm climates, water drawn by the turbine from deep in a reservoir can be deficient in dissolved oxygen (DO), a critical element in maintaining a healthy aquatic ecosystem. Many different solutions have been proposed in order to increase the DO levels in turbine discharge, including: turbine aeration systems (adding air to the water through either the turbine hub, the periphery or through distributed aeration in the runner blades); bubble diffusers in the reservoir or in the tailrace; aerating weirs downstream of the dams; and surface water pumps in the reservoir near the dam. There is a significant potential to increase the effectiveness of these solutions by improving the way that oxygen is introduced into the water; better distributions of bubbles will result in better oxygen transfer. In the present study, a two-phase Computational Fluid Dynamics model has been formulated using a commercial code to study the distribution of air downstream of a simple aerating hydrofoil. The two-phase model uses the Eulerian-Eulerian approach. Appropriate relations are used to model the interphase forces, including the Grace drag force model, the Favre averaged drag force and the Sato enhanced eddy viscosity. The model is validated using experimental results obtained in the water tunnel at the University of Minnesota's Saint Anthony Falls Laboratory. Results are obtained for water velocities between 5 and 10 m/s, air flow rates between 0.5 and 1.5 sL/min and for angles of attack between 0° and -8°. The results of this study show that the CFD model provides a good qualitative comparison to the experimental results by well predicting the wake location at the different flow rates and angles of attack used

  16. CFD model of an aerating hydrofoil

    Science.gov (United States)

    Scott, D.; Sabourin, M.; Beaulieu, S.; Papillon, B.; Ellis, C.

    2014-03-01

    Improving water quality in the tailrace below hydroelectric dams has become a priority in many river systems. In warm climates, water drawn by the turbine from deep in a reservoir can be deficient in dissolved oxygen (DO), a critical element in maintaining a healthy aquatic ecosystem. Many different solutions have been proposed in order to increase the DO levels in turbine discharge, including: turbine aeration systems (adding air to the water through either the turbine hub, the periphery or through distributed aeration in the runner blades); bubble diffusers in the reservoir or in the tailrace; aerating weirs downstream of the dams; and surface water pumps in the reservoir near the dam. There is a significant potential to increase the effectiveness of these solutions by improving the way that oxygen is introduced into the water; better distributions of bubbles will result in better oxygen transfer. In the present study, a two-phase Computational Fluid Dynamics model has been formulated using a commercial code to study the distribution of air downstream of a simple aerating hydrofoil. The two-phase model uses the Eulerian-Eulerian approach. Appropriate relations are used to model the interphase forces, including the Grace drag force model, the Favre averaged drag force and the Sato enhanced eddy viscosity. The model is validated using experimental results obtained in the water tunnel at the University of Minnesota's Saint Anthony Falls Laboratory. Results are obtained for water velocities between 5 and 10 m/s, air flow rates between 0.5 and 1.5 sL/min and for angles of attack between 0° and -8°. The results of this study show that the CFD model provides a good qualitative comparison to the experimental results by well predicting the wake location at the different flow rates and angles of attack used.

  17. Investigation on Improved Correlation of CFD and EFD for Supercritical Airfoil

    Directory of Open Access Journals (Sweden)

    Xin Xu

    2014-02-01

    Full Text Available It is necessary to improve the correlation between CFD and EFD through the correction of EFD results and validation of CFD method, thus investigating the aerodynamic characteristics of supercritical airfoil perfectly. In this study, NASA SC (2 -0714 airfoil is numerically simulated and compared with NASA corrected experimental results to validate the CFD method. The Barnwell-Sewell method is applied to correct sidewall effects for experimental results of typical supercritical airfoil CH obtained in NF-6 wind tunnel. It is shown that there was large disparity between CFD and uncorrected EFD results, while CFD and EFD compared well after correction. The CFD method is validated and the Barnwell-Sewell method is feasible for sidewall effects correction. The correlation of EFD and CFD improved after the correction of EFD results and validation of CFD method.

  18. Removing Grit During Wastewater Treatment: CFD Analysis of HDVS Performance.

    Science.gov (United States)

    Meroney, Robert N; Sheker, Robert E

    2016-05-01

    Computational Fluid Dynamics (CFD) was used to simulate the grit and sand separation effectiveness of a typical hydrodynamic vortex separator (HDVS) system. The analysis examined the influences on the separator efficiency of: flow rate, fluid viscosities, total suspended solids (TSS), and particle size and distribution. It was found that separator efficiency for a wide range of these independent variables could be consolidated into a few curves based on the particle fall velocity to separator inflow velocity ratio, Ws/Vin. Based on CFD analysis it was also determined that systems of different sizes with length scale ratios ranging from 1 to 10 performed similarly when Ws/Vin and TSS were held constant. The CFD results have also been compared to a limited range of experimental data. PMID:27131307

  19. Adaptive Distributed Data Structure Management for Parallel CFD Applications

    KAUST Repository

    Frisch, Jerome

    2013-09-01

    Computational fluid dynamics (CFD) simulations require a lot of computing resources in terms of CPU time and memory in order to compute with a reasonable physical accuracy. If only uniformly refined domains are applied, the amount of computing cells is growing rather fast if a certain small resolution is physically required. This can be remedied by applying adaptively refined grids. Unfortunately, due to the adaptive refinement procedures, errors are introduced which have to be taken into account. This paper is focussing on implementation details of the applied adaptive data structure management and a qualitative analysis of the introduced errors by analysing a Poisson problem on the given data structure, which has to be solved in every time step of a CFD analysis. Furthermore an adaptive CFD benchmark example is computed, showing the benefits of an adaptive refinement as well as measurements of parallel data distribution and performance. © 2013 IEEE.

  20. Introducing CFD in the optical simulation of linear Fresnel collectors

    Science.gov (United States)

    Moghimi, M. A.; Rungasamy, A.; Craig, K. J.; Meyer, J. P.

    2016-05-01

    This paper seeks to determine whether the Finite Volume method within a commercially available Computational Fluid Dynamics (CFD) solver (ANSYS Fluent) can model radiation with comparable accuracy to a Monte Carlo ray-tracing software package (SolTrace). A detailed investigation was performed into modeling techniques that can be used to significantly reduce the optical errors traditionally associated with CFD modeling of radiation false scattering and ray effect using a simple optical test case. The strategies formulated in the first part of this paper were used to model a variety of Linear Fresnel Collector Concentrating Solar Power Plants. This paper shows that commercial CFD packages yield accurate results for line focusing concentrating solar applications and simple geometries, validating its use in an integrated environment where both optical and thermal performance of these plants can be simulated and optimized.

  1. CFD Aided Design and Production of Hydraulic Turbines

    Science.gov (United States)

    Kaplan, Alper; Cetinturk, Huseyin; Demirel, Gizem; Ayli, Ece; Celebioglu, Kutay; Aradag, Selin; ETU Hydro Research Center Team

    2014-11-01

    Hydraulic turbines are turbo machines which produce electricity from hydraulic energy. Francis type turbines are the most common one in use today. The design of these turbines requires high engineering effort since each turbine is tailor made due to different head and discharge. Therefore each component of the turbine is designed specifically. During the last decades, Computational Fluid Dynamics (CFD) has become very useful tool to predict hydraulic machinery performance and save time and money for designers. This paper describes a design methodology to optimize a Francis turbine by integrating theoretical and experimental fundamentals of hydraulic machines and commercial CFD codes. Specific turbines are designed and manufactured with the help of a collaborative CFD/CAD/CAM methodology based on computational fluid dynamics and five-axis machining for hydraulic electric power plants. The details are presented in this study. This study is financially supported by Turkish Ministry of Development.

  2. Estimating Flow-Through Balance Momentum Tares with CFD

    Science.gov (United States)

    Melton, John E.; James, Kevin D.; Long, Kurtis R.; Flamm, Jeffrey D.

    2016-01-01

    This paper describes the process used for estimating flow-through balance momentum tares. The interaction of jet engine exhausts on the BOEINGERA Hybrid Wing Body (HWB) was simulated in the NFAC 40x80 wind tunnel at NASA Ames using a pair of turbine powered simulators (TPS). High-pressure air was passed through a flow-through balance and manifold before being delivered to the TPS units. The force and moment tares that result from the internal shear and pressure distribution were estimated using CFD. Validation of the CFD simulations for these complex internal flows is a challenge, given limited experimental data due to the complications of the internal geometry. Two CFD validation efforts are documented, and comparisons with experimental data from the final model installation are provided.

  3. Study of tip loss corrections using CFD rotor computations

    Science.gov (United States)

    Shen, W. Z.; Zhu, W. J.; Sørensen, J. N.

    2014-12-01

    Tip loss correction is known to play an important role for engineering prediction of wind turbine performance. There are two different types of tip loss corrections: tip corrections on momentum theory and tip corrections on airfoil data. In this paper, we study the latter using detailed CFD computations for wind turbines with sharp tip. Using the technique of determination of angle of attack and the CFD results for a NordTank 500 kW rotor, airfoil data are extracted and a new tip loss function on airfoil data is derived. To validate, BEM computations with the new tip loss function are carried out and compared with CFD results for the NordTank 500 kW turbine and the NREL 5 MW turbine. Comparisons show that BEM with the new tip loss function can predict correctly the loading near the blade tip.

  4. Study of tip loss corrections using CFD rotor computations

    International Nuclear Information System (INIS)

    Tip loss correction is known to play an important role for engineering prediction of wind turbine performance. There are two different types of tip loss corrections: tip corrections on momentum theory and tip corrections on airfoil data. In this paper, we study the latter using detailed CFD computations for wind turbines with sharp tip. Using the technique of determination of angle of attack and the CFD results for a NordTank 500 kW rotor, airfoil data are extracted and a new tip loss function on airfoil data is derived. To validate, BEM computations with the new tip loss function are carried out and compared with CFD results for the NordTank 500 kW turbine and the NREL 5 MW turbine. Comparisons show that BEM with the new tip loss function can predict correctly the loading near the blade tip

  5. Trends in spatio-temporal distribution of Peruvian anchovy and other small pelagic fish biomass from 1966-2009 Tendencias espacio-temporales en la distribución de la biomasa de anchoveta peruana y de otros peces pelágicos pequenos entre 1966 y 2009

    Directory of Open Access Journals (Sweden)

    Mariano Gutiérrez

    2012-09-01

    de pequenos peces pelágicos de la región norte del Sistema de la Corriente de Humboldt (NHCS son el producto de la variación de forzantes ambientales en diferentes escalas de tiempo y espacio que influyen entre el ecosistema 'frío' costero y el oceánico 'cálido'. La información para estudiar estas fluctuaciones provienen mayormente de las pesquerías, y muestran que la anchoveta (Engraulis ringens incrementa su abundancia cuando la de sardina (Sardinops sagax declina y viceversa. Sin embargo, utilizando datos acústicos de biomasa latitudinal se muestra que otras especies como la caballa (Scomber japonicus y el jurel (Trachurus murphyi también siguen la misma tendencia opuesta a anchoveta, lo que en principio indica que los datos pesqueros disponibles no indican la verdadera dimensión del balance de abundancia entre especies. Utilizando diagramas de Hovmoller se analizan los cambios en la biomasa acústica latitudinal, capturas e influencia de eventos El Nino ocurridos entre 1966 y 2009 con el objetivo de describir: 1 cómo el patrón de distribución decadal de anchoveta se movió de sur a norte desde la década de 1960, 2 cómo se han producido cambios concomitantes en la abundancia latitudinal de otras especies tales como sardina, caballa y jurel antes, durante y después de eventos El Nino, y 3 cuál fue el efecto general de la sucesión de eventos El Nino sobre todas estas especies. Se concluye que: a cada evento El Nino ha tenido un efecto en la expansión o contracción de la distribución de especies pelágicas, con diferente gradiente latitudinal, y b El Nino 1997-98 no disparó sino aceleró la fase declinante de la abundancia de sardina, caballa y jurel al reducirse el tamano de su hábitat ideal debido a una expansión del hábitat costero que presentó además un acercamiento a la superficie del límite superior de la Zona Mínima de Oxígeno (MOZ. Las observaciones logradas con datos acústicos podrían ser tomadas en consideración para el

  6. EVALUACIÓN DEL CONTENIDO DE NUTRIENTES Y PRODUCCIÓN DE BIOMASA EN CEPAS DE LEVADURA COLOMBIANAS Y COMERCIALES EVALUATION OF THE NUTRIENT CONTENT AND BIOMASS PRODUCTION IN COLOMBIAN AND COMMERCIAL YEAST STRAINS

    Directory of Open Access Journals (Sweden)

    Nohora Patricia Manovacía Moreno

    2008-12-01

    Full Text Available En el presente estudio se evaluó la producción de biomasa, el contenido de algunos nutrientes (selenio, carbohidratos totales y proteína microbiana y el consumo de sustrato de cepas de levaduras comerciales y nativas pertenecientes al Banco de Germoplasma de la Nación Colombiana, manejado por la Corporación Colombiana de Investigación Agropecuaria, CORPOICA. Inicialmente se determinó el crecimiento de tres levaduras nativas seleccionadas al azar bajo diferentes condiciones de pH, temperatura y tiempo de fermentación usando un medio líquido de extracto de malta. Dentro de estas condiciones, las mejores respuestas se observaron a pH de 4,5, 25 °C y 24 horas de fermentación. Usando estas condiciones se evaluaron 100 accesiones de levaduras nativas y 4 comerciales por su producción de biomasa, contenido de selenio, carbohidratos totales y proteína microbiana y consumo de sustratos. De acuerdo con estas variables y un análisis de conglomerados fue posible agrupar las levaduras en grupos homogéneos. Hubo elevada variabilidad en la producción de biomasa entre las 104 cepas evaluadas, probablemente debido a la variabilidad biológica existente en la población estudiada. Los rendimientos de biomasa variaron entre 0,101 y 0,480 g de biomasa g-1 de azúcar consumido y las velocidades de producción de biomasa oscilaron entre 0,040 y 0,185 g L-1 h-1. El consumo promedio de nutrientes (g de nutrientes consumidos/ g de nutrientes disponibles fue de 91,6% en el caso de los carbohidratos y de 17,8% en el caso de la proteína. Se identificaron diez cepas de superior crecimiento y contenido de nutrientes, cuyo potencial prebiótico y probiótico será evaluado en futuros ensayos In vivo.In the present study biomass production and nutrient (selenium, total carbohydrate and microbial protein were evaluated in both commercial and native yeast isolates from the Colombian Germplasm Bank managed by the Colombian Corporation of Agricultural Research

  7. Estimación de biomasa y carbono en dos especies de bosque mesófilo de montaña Biomass and carbon assessment in two tree species in a cloudy forest

    Directory of Open Access Journals (Sweden)

    Miguel Acosta Mireles

    2011-08-01

    Full Text Available La generación de ecuaciones alométricas es importante para determinar la biomasa y el carbono en las especies arbóreas. Esta información es útil en los estudios de cambio climático. En el presente estudio se generaron ecuaciones alométricas para dos especies de importancia ecológica en el bosque mesófilo de montaña: Clethra mexicana DC y Alnus arguta (Schltdl Spach. Las ecuaciones que se determinaron son de la forma Y= bXk; donde: Y= contenido de biomasa o de carbono (kg; y X= diámetro normal (DN en centímetros. Para estimar los valores b y k del modelo para cada especie, se realizó un muestreo de quince árboles de Clethra mexicana y 22 de Alnus arguta. En Clethra mexicana el mayor porcentaje de biomasa 45.2 % se encontró en el fuste incluido el tocón, mientras que en las ramas y el follaje estaba 36.3% y 18.6%, respectivamente. Con la biomasa y el DN de los árboles se determinaron los parámetros b y k del modelo propuesto (B= 0.4632 DN1.8168, R²= 0.946. Para Alnus arguta el mayor porcentaje de biomasa (60.6%, se encontró en el fuste incluido el tocón, mientras que en las ramas y el follaje presentó 27.4 y 12%, respectivamente. Al igual que el caso anterior con la biomasa y el DN, se obtuvieron los parámetros b y k del modelo propuesto (B= 0.1649 DN2.2755, R²= 0.968. Después de analizar el contenido de carbono en las muestra de cada especie, se ajustaron las ecuaciones para Clethra mexicana C= 22.49DN1.8168, con R²= 0.946, mientras que para Alnus arguta C= 0.0809DN2.2782 con R²= 0.968.The generation of allometric equations is important to determine biomass and carbon in tree species. This information is useful in climate change studies. In this paper, allometric equations were generated for two species of ecological importance in the cloud forest: Clethra mexicana DC and Alnus arguta (Schltdl Spach. Equations determined are of the form Y= bXk; where: Y= biomass or carbon content (kg; and X= normal diameter (ND in

  8. Lotus tenuis Seedling Establishment and Biomass Production in Flooding Pampa Grasslands (Buenos Aires , Argentina Establecimiento de Plántulas y Producción de Biomasa de Lotus tenuis en Pastizales de la Pampa Deprimida (Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Osvaldo R Vignolio

    2011-03-01

    Full Text Available Biomass and plant density of Lotus tenuis Waldst. & Kit. ex Willd. have been reported in decreasing in grasslands and pastures. Our objective was to determine if L. tenuis biomass and plant density can be increased in grassland through seed addition. Two separated experiments under cattle grazing exclusion were conducted in three paddocks of a Flooding Pampa grassland. The first experiment was from autumn 2004 to autumn 2006 and the second from autumn 2005 to autumn 2007. Different L. tenuis seed additions (0, 57, 229, 917 and 1833 seeds m-² were broadcast into experimental plots. In the second experiment, besides seed additions there was a reseeding of approximately 900 seed m-² from seed rain produced by plants of grassland. Seed density explained the 81% and 19% of the variation in seedling density and L. tenuis biomass, respectively. Seedling emergence occurred mainly between autumn and early spring, while seedling mortality was mainly between late spring and early summer. Lotus tenuis adult plant density and biomass production increased with seed additions. Total biomass production in the plant community varied between 589.94 ± 26.89 and 1042.44 ± 54.39 g m-² yr-1 and the differences were principally attributed to precipitations. Lotus tenuis biomass contribution was of approximately 10%. The results suggest that L. tenuis seedling and plant establishment and biomass production can be increased through seed addition and/or seed rain through grazing exclusion during reproductive period.En pastizales y pasturas ha sido documentada la reducción de la densidad de plantas y de la biomasa de Lotus tenuis Waldst. & Kit. ex Willd. Nuestro objetivo fue determinar si su densidad de plantas y su producción de biomasa pueden ser incrementadas en un pastizal mediante la adición de semillas. Dos experimentos sin pastoreo fueron realizados en tres potreros de un pastizal de la Pampa Deprimida. El primer experimento fue realizado entre otoño 2004

  9. A CFD/CSD interaction methodology for aircraft wings

    Energy Technology Data Exchange (ETDEWEB)

    Bhardwaj, M.K.; Kapania, R.K. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States); Reichenbach, E. [Boeing Co., St. Louis, MO (United States); Guruswamy, G.P. [NASA, Moffett Field, CA (United States). Ames Research Center

    1998-01-01

    With advanced subsonic transports and military aircraft operating in the transonic regime, it is becoming important to determine the effects of the coupling between aerodynamic loads and elastic forces. Since aeroelastic effects can significantly impact the design of these aircraft, there is a strong need in the aerospace industry to predict these interactions computationally. Such an analysis in the transonic regime requires high fidelity computational fluid dynamics (CFD) analysis tools, due to the nonlinear behavior of the aerodynamics in the transonic regime and also high fidelity computational structural dynamics (CSD) analysis tools. Also, there is a need to be able to use a wide variety of CFD and CSD methods to predict aeroelastic effects. Since source codes are not always available, it is necessary to couple the CFD and CSD codes without alteration of the source codes. In this study, an aeroelastic coupling procedure is developed to determine the static aeroelastic response of aircraft wings using any CFD and CSD code with little code integration. The aeroelastic coupling procedure is demonstrated on an F/A-18 Stabilator using NASTD (an in-house McDonnell Douglas CFD code) and NASTRAN. In addition, the Aeroelastic Research Wing (ARW-2) is used for demonstration of the aeroelastic coupling procedure by using ENSAERO (NASA Ames Research Center CFD code) and a finite element wing-box code. The results obtained from the present study are compared with those available from an experimental study conducted at NASA Langley Research Center and a study conducted at NASA Ames Research Center using ENSAERO and modal superposition. The results compare well with experimental data.

  10. CFD Simulation of the NREL Phase VI Rotor

    OpenAIRE

    Song, Yang; Perot, J. Blair

    2014-01-01

    The simulation of the turbulent and potentially separating flow around a rotating, twisted, and tapered airfoil is a challenging task for CFD simulations. This paper describes CFD simulations of the NREL Phase VI turbine that was experimentally characterized in the 24.4m x 36.6m NREL/NASA Ames wind tunnel (Hand et al., 2001). All computations in this article are performed on the experimental base configuration of 0o yaw angle, 3o tip pitch angle, and a rotation rate of 72 rpm. The significanc...

  11. The role of CFD computer analyses in hydrogen safety management

    Energy Technology Data Exchange (ETDEWEB)

    Komen, Ed M.J.; Visser, Dirk C.; Roelofs, Ferry [Nuclear Research and Consultancy Group (NRG), Petten (Netherlands); Te Lintelo, Jos G.T. [N.V. Elekticiteits-Productiemaatschappij Zuid-Nederland EPZ, Borssele (Netherlands)

    2015-11-15

    The risks of hydrogen release and combustion during a severe accident in a light water reactor have attracted considerable attention after the Fukushima accident in Japan. Reliable computer analyses are needed for the optimal design of hydrogen mitigation systems. In the last decade, significant progress has been made in the development, validation, and application of more detailed, three-dimensional Computational Fluid Dynamics (CFD) simulations for hydrogen safety analyses. The validation status and reliability of CFD code simulations will be illustrated by validation analyses performed for experiments executed in the PANDA, THAI, and ENACCEF facilities.

  12. Fifty years of CFD for room air distribution

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm

    2015-01-01

    Computational fluid dynamics (CFD) was first introduced in the ventilation industry in the 1970s. CFD has been increasingly used since then, as testified by the number of peer-reviewed articles, which was less than 10 per year in the 1990s, and which is now 60 to 70 per year. This article discusses......, and to addressing situations with more steady-state solutions. The article finishes with a number of different case studies such as design of air supply openings, smoke management in buildings, cross-infection risks from the exhalation of particles and calculation of people moving in a room. The use of benchmark...

  13. Experimental and CFD analysis of nozzle position of subsonic ejector

    Institute of Scientific and Technical Information of China (English)

    Xilai ZHANG; Shiping JIN; Suyi HUANG; Guoqing TIAN

    2009-01-01

    The influence of nozzle position on the performance of an ejector was analyzed qualitatively with free jet flow model. Experimental investigations and computational fluid dynamics (CFD) analysis of the nozzle position of the subsonic ejector were also conducted. The results show that there is an optimum nozzle position for the ejector. The ejecting coefficient reaches its maximum when the nozzle is positioned at the optimum and decreases when deviating. Moreover, the nozzle position of an ejector is not a fixed value, but is influenced greatly by the flow parameters. Considering the complexity of the ejector, CFD is reckoned as a useful tool in the design of ejectors.

  14. Biomasa microbiana y actividad ureasa del suelo en una pradera permanente pastoreada de Chile Soil microbial biomass and urease activity in a grazed permanent pasture from Chile

    Directory of Open Access Journals (Sweden)

    Pedro Antonio Núñez Ramos

    2012-12-01

    Full Text Available En los sistemas de pasturas; la productividad de la pradera puede estar influenciada por el manejo; debido a su impacto sobre los microorganismos del suelo y el reciclaje de nutrientes. El objetivo de este trabajo fue evaluar la biomasa microbiana (BM del suelo asociada al nitrógeno (BMN; carbono (BMC y la actividad ureasa (AU en una pradera permanente del sur de Chile. Entre la primavera de 2005 y el invierno de 2006 fueron evaluados dos sistemas de pastoreo: pastoreo intenso (PI; pastoreo suave (PS y un tratamiento control (C. El diseño fue en bloques al azar con tres repeticiones. En relación a los valores promedios medidos de las variables en pre y post pastoreo; se produjo un incremento en los contenidos de CB en un 21,8 y 8,6% para PI y PS; mientras que en el control fue sólo de 1,9%. Los contenidos de NB también fueron incrementados en un 16 y 19% para PI y PS; respectivamente en comparación con el control (4%. La actividad ureasa aumentó en 13 y 27% para PI y PS; respectivamente en comparación con el control (5%. El pastoreo; produce un flujo más alto de residuos orgánicos en el suelo; lo que estimula la actividad de la biomasa microbiana y; por tanto; aumentó la AU y los contenidos de CB y NB. Esto sugiere que; en los sistemas de pastoreo; se mejora la fertilidad biológica de los suelos y la disponibilidad de nutrientes.In pasture systems, management practices can affect pasture productivity differently due to their impact on soil microorganisms and nutrient cycling. The objective of this study was to evaluate the relationship between soil microbial biomass (MB nitrogen (MBN, carbon (MBC and urease activity (UA in a permanent pasture in southern Chile. Two grazing systems were evaluated between spring 2005 and winter 2006 : heavy grazing (HG, light grazing (LG and a control treatment (C. Treatments were arranged in a randomized block design with three replications. Concerning the average values of the variables measured at

  15. 三菱重工業における風洞試験とCFD

    OpenAIRE

    Nomoto, Hideki; Miyakawa, Jun-ichi; 野本, 秀喜; 宮川, 淳一

    1991-01-01

    Computational Fluid Dynamics (CFD) has established its unique position as a design tool in aerospace industries. As the CFD technology has evolved, the relationship with the conventional design tool of wind tunnel testing has also changed accordingly. This paper reviews the relationship of the two major technologies in Mitsubishi Nagoya. The typical CFD application are briefly introduced during the discussion.

  16. Estudio de centrales de biomasa a pequeña escala como fuente de energía en las zonas rurales de la región de Göttingen (Alemania)

    OpenAIRE

    Veinat Grimalt, Francisca

    2013-01-01

    Las plantas de digestión anaerobia de biomasa se presentan como una buena opción tanto para la valorización económica de purines como para la obtención de energía a partir de fuentes renovables produciendo biogás. Dicha producción se puede mejorar mediante la co-digestión de los purines con cosustratos agrícolas o agroindustriales. A partir de las anteriores premisas se ha desarrollado en la región alemana de Göttingen los denominados pueblos bioenergéticos. Los cuales con recursos locale...

  17. Cambios en el porcentaje de sodio intercambiable (PSI) y la relación de absorción de sodio (RAS) de un suelo y su influencia en la actividad y biomasa microbiana

    OpenAIRE

    Torrente Trujillo Armando; Gasca Cesar A.; Menjivar Juan Carlos

    2011-01-01

    Con el objetivo de evaluar los cambios en el PSI, la RAS y su influencia en la actividad y  biomasa  microbiana  del suelo,  se aplicaron  diversas  concentraciones  de vinaza  como enmienda procedente de la industria de alcohol carburante, sobre un suelo afectado por sodicidad con severas limitaciones en las condiciones físicas, químicas y biológicas. Se aplicó un diseño en bloques completos al azar que incluye cuatro tratamientos y tres repeticiones, y muestreos de suelo al inicio ...

  18. Producción de biomasa verde y calidad de aceites esenciales de palmarosa (Cymbopogon martini Roxb. con aplicación de fertilizantes de síntesis y orgánicos

    Directory of Open Access Journals (Sweden)

    Javier Alberto Pinzón-Torres

    2014-12-01

    Full Text Available El uso de fertilizantes minerales en cultivos de Cymbopogon martini Roxb. (Palmarosa con el fin de incrementar la biomasa y el rendimiento de aceite esencial (AE es una práctica cada vez más frecuente. Este aceite es rico en geraniol y acetato de geranilo, moléculas con alto valor en las industrias de productos cosméticos y farmacéutica. Las plantas fueron obtenidas del Centro Nacional de Investigación Agroindustrial de Plantas Aromaticas y Medicinales de la Universidad Industrial de Santander (UIS (Cenivam (07° 08' 31.68"N, 73° 07' 06.14O; 988 m.s.n.m., Santander, Colombia. El objetivo del estudio fue evaluar la productividad de biomasa y analizar la calidad y el rendimiento de los aceites esenciales (AE de este cultivo con la aplicación de tres tipos de fertilizantes químico: Nutrimon® 14-14-14, NPK granulado (10% N, 14% P2O5 , 14% K2O, en dosis de 2, 4 y 6 g/planta, más un tratamiento con 400 g de un fertilizante orgánico,. Se utilizó un diseño de bloques completos al azar, con trece tratamientos y tres cosechas de tres plantas cada una como repeticiones. Los datos fueron sometidos a análisis de variancia con comparación de las medias por la prueba de Tukey a 5% de probabilidad. No se observaron correlaciones entre biomasa y rendimiento del AE en función del tipo del fertilizante aplicado, lo que sugirió que los tratamientos que incrementaron la producción de biomasa no necesariamente representaron mayor rendimiento del AE y viceversa. Se encontró que los fertilizantes orgánicos son ideales para este cultivo, ya que favorecieron rendimientos relativamente altos en aceite, con altos porcentajes de geraniol y acetato de geranilo.

  19. Abundancia y biomasa de organismos edáficos en tres usos del terreno en el altiplano de Pasto, Colombia Abundance and biomass of soil organisms in three land use systems in the high plateau of Pasto, Colombia

    Directory of Open Access Journals (Sweden)

    Jorge H. Castro P.

    Full Text Available La investigación se realizó en la vereda Cruz de Amarillo, municipio de Pasto (1º 7' norte y 77º 17´ oeste, 2.850 msnm, 12º C y humedad relativa del 83%. Se seleccionaron tres usos del terreno: praderas de Lollium multiflorum (ryegrass y Pennisetum clandestinum (kikuyo y un bosque secundario. En cada uno se trazó una línea recta y se tomaron ocho muestras, separadas 10 m, cada 15 días. El muestreo se hizo siguiendo la metodología del Tropical Soil Biology and Fertility Programe (TSBF. La fauna se recolectó manualmente y posteriormente se hizo el conteo y la valoración de la biomasa; los organismos se identificaron hasta nivel de familia y en algunos casos sólo hasta orden. También se determinó humedad gravimétrica, porosidad y contenido de materia orgánica. Los datos se analizaron de acuerdo con un diseño de bloques completos al azar. La pradera de L. multiflorum y el bosque secundario presentaron los mayores valores de abundancia de lombrices (5.648 y 4.864 ind m-2 y biomasa (141.3 y 670.7 g.p.f.m-2. En la pradera de P. clandestinum abundaron los ácaros (2.768 ind m-2 con una biomasa de 0.22 g. p. f m-2. En todos los usos del suelo la mayor abundancia de organismos y biomasa se presentó en la profundidad de 0 - 10 cm.At the county of Cruz de Amarillo, municipality of Pasto, Colombia , located al 2850 masl, a field study to determine the numbers of organisms and its biomass was carried out. Three land use systems were selected: prairie with the grass Lolium multiflorum (Ryegrass, pasture with Pennisetum clandestinum (kikuyu and secondary forest. The prairie of .L multiflorum and the secondary forest showed the highest values of abundance of earth worms (5648 and 4864 ind m-2, respectively. Biomass was 141.3 and 670.7 gpfm-2 for L. multiflorum and P. clandestinum, respectively. Mites were abundant (2768 ind m-2 with a biomass of 0.22 gpfm-2. At all land use systems, the highest abundance of organisms and biomass at 2 depth of

  20. Estado del Arte del Uso del Gas de Gasificación Termoquímica de Biomasa(GG), en Motores de Combustión Interna Alternativos

    OpenAIRE

    Fonseca Gonzalez, Natalia Elizabeth

    2003-01-01

    El presente trabajo, desarrollado en el marco del Convenio de Cooperación educativa entre la ETSII - UPM y el Ciemat, se realiza con el fin de determinar líneas futuras de investigación y/o aplicación de la tecnología de gasificación termoquímica de biomasa integrada a motores de combustión interna alternativos (MCIA) para generación de potencia, motivados por la necesidad de reducir las emisiones contaminantes, aumentar el uso de las fuentes renovables de energía, reducir la dependencia econ...

  1. Efecto de la fertilización sobre la producción de biomasa y la absorción de nutrientes en Brachiaria decumbens y Brachiaria híbrido Mulato

    OpenAIRE

    Navajas Martínez, Víctor Manuel

    2011-01-01

    Los suelos utilizados para la actividad ganadera generalmente son de baja fertilidad y alta acidez, lo cual genera bajas productividades. Existen cultivares de pasto Brachiaria que se adaptan a dichas condiciones adversas, pero se desconoce su comportamiento en condiciones agroecológicas de Barrancabermeja, Santander. El objetivo de esta investigación fue evaluar el efecto de la fertilización sobre la producción de biomasa y la absorción de nutrientes por los pastos Brachiaria decumbens y ...

  2. Rendimiento de biomasa y aceite esencial de quimiotipos de Lippia alba (Mill.) N. E. Brown en respuesta a las prácticas agronómicas, y sus propiedades farmacológicas

    OpenAIRE

    Blanco, Marcos

    2014-01-01

    Esta tesis estudia experimentalmente la respuesta de plantas cultivadas pertenecientes a cuatro quimiotipos de Lippia alba (carvona, dihidrocarvona, citral y linalol) ante la implementación de distintas técnicas de manejo agronómico. Se analizó la incidencia de la distancia de plantación y época de corte de la planta sobre el rendimiento de biomasa, de droga cruda (hoja seca) y aceite esencial en los diferentes quimiotipos evaluados. El rendimiento de droga cruda no fue afectado por las difer...

  3. Obtención de un hidrolizado detoxificado a partir de biomasa lignocelulósica de Panicum maximum para su uso como sustrato en la fermentación alcohólica

    OpenAIRE

    Castillo Saldarriaga, Carlos Rafael

    2014-01-01

    El objetivo de esta investigación fue estudiar el efecto de una alta concentración de sólidos en la etapa de pretratamiento e hidrólisis enzimática empleando como materia prima biomasa lignocelulósica de Panicum maximum. Posteriormente, se evaluaron dos tratamientos de detoxificación de hidrolizados con el objetivo de ser usados como sustrato para la producción de etanol. Como pretratamiento se seleccionó ácido sulfúrico diluido. Las condiciones de pretratamiento evaluadas fueron: concentraci...

  4. Diseño y contraste de nuevos modelos de estimación del potencial energético de biomasa forestal en el Territorio de Bizkaia mediante técnicas de análisis estadístico espacial usando herramientas GIS con datos LiDAR

    OpenAIRE

    Torre Tojal, Leyre

    2016-01-01

    RESUMEN: El objetivo de esta tesis doctoral es desarrollar un modelo que permita estimar la biomasa aérea para la especie Pinus radiata en la comarca de Arratia-Nervión, (Bizkaia), a partir del uso exclusivo de los datos del vuelo LiDAR realizado por Gobierno Vasco en 2012. En el proceso, se han utilizado los datos de campo del Inventario Forestal Nacional 4 como base para estimar la biomasa de contraste. Partiendo de las nubes de puntos LiDAR y tras su procesado, se han calculado diversa...

  5. Combining CFD simulation with experimental RTD function for hydrocyclone separator studies

    International Nuclear Information System (INIS)

    The first part of this report presents radiotracer experimental Residence Time Distribution (RTD) functions for hydrocyclone separators, their analysis and macro modelling. The second part of the report presents the Computational Fluid Dynamics (CFD) simulation for the hydrocyclone. Combining the experimental data and the CFD simulation results allows understanding the fundamental principles of the flow and solids' separation in hydrocyclone. The experimental data help choosing the proper parameters for CFD simulation and from the other side the CFD results allow better analysis and macro modelling of the experimental data. Radiotracer methods have been used for industrial experiments. For CFD simulation the FLUENT software has been applied. (author)

  6. CFD modeling of fouling in crude oil pre-heaters

    International Nuclear Information System (INIS)

    Highlights: ► A conceptual CFD-based model to predict fouling in industrial crude oil pre-heaters. ► Tracing fouling formation in the induction and developing continuation periods. ► Effect of chemical components, shell-side HTC and turbulent flow on the fouling rate. - Abstract: In this study, a conceptual procedure based on the computational fluid dynamic (CFD) technique has been developed to predict fouling rate in an industrial crude oil pre-heater. According to the developed CFD concept crude oil was assumed to be composed of three pseudo-components comprising of petroleum, asphaltene and salt. The binary diffusion coefficients were appropriately categorized into five different groups. The species transport model was applied to simulate the mixing and transport of chemical species. The possibility of adherence of reaction products to the wall was taken into account by applying a high viscosity for the products in competition with the shear stress on the wall. Results showed a reasonable agreement between the model predictions and the plant data. The CFD model could be applied to new operating conditions to investigate the details of the crude oil fouling in the industrial pre-heaters.

  7. Fully consistent CFD methods for incompressible flow computations

    DEFF Research Database (Denmark)

    Kolmogorov, Dmitry; Shen, Wen Zhong; Sørensen, Niels N.;

    2014-01-01

    Nowadays collocated grid based CFD methods are one of the most e_cient tools for computations of the ows past wind turbines. To ensure the robustness of the methods they require special attention to the well-known problem of pressure-velocity coupling. Many commercial codes to ensure the pressure...

  8. CFD code comparison for 2D airfoil flows

    DEFF Research Database (Denmark)

    Sørensen, Niels N.; Méndez, B.; Muñoz, A.;

    2016-01-01

    The current paper presents the effort, in the EU AVATAR project, to establish the necessary requirements to obtain consistent lift over drag ratios among seven CFD codes. The flow around a 2D airfoil case is studied, for both transitional and fully turbulent conditions at Reynolds numbers of 3 × ...

  9. Reproducible and replicable CFD: it's harder than you think

    CERN Document Server

    Mesnard, Olivier

    2016-01-01

    Completing a full replication study of our previously published findings on bluff-body aerodynamics was harder than we thought. Despite the fact that we have good reproducible-research practices, sharing our code and data openly. Here's what we learned from three years, four CFD codes and hundreds of runs.

  10. Investigation of microclimate between wall and furniture with CFD

    DEFF Research Database (Denmark)

    Mortensen, Lone Hedegaard; Woloszyn, Monika; Rode, Carsten;

    2005-01-01

    In ordinary building simulation tools for moisture modelling it is common to look very detailed on heat and moisture distributions in constructions while assuming fully mixed conditions in the room air so it is represented by only one node. Opposite, CFD models are used for detailed analysis of a...

  11. CFD modelling of moisture interactions between air and constructions

    DEFF Research Database (Denmark)

    Mortensen, Lone Hedegaard; Woloszyn, Monika; Hohota, Raluca;

    2005-01-01

    There is a strong demand for accurate moisture modelling since moisture poses a risk for both the constructions and the indoor climate. Thus, in this investigation there is special focus on moisture modelling. The paper describes a new model based on a CFD tool that is enhanced to include both de...

  12. Study of tip loss corrections using CFD rotor computations

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Zhu, Wei Jun; Sørensen, Jens Nørkær

    2014-01-01

    computations for wind turbines with sharp tip. Using the technique of determination of angle of attack and the CFD results for a NordTank 500 kW rotor, airfoil data are extracted and a new tip loss function on airfoil data is derived. To validate, BEM computations with the new tip loss function are carried out...

  13. Recommendations for CFD Simulation of Reactor Internal Flow

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gong Hee; Bang, Young Seok; Woo, Sweng Woong; Cheong, Ae Ju [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2013-10-15

    The inlet nozzle-to-outlet nozzle pressure losses inside reactor model were used for the verification of the magnitudes calculated by pressure loss methods. Although the competitiveness of CFD is continuously growing due to the rapid developments in computer hardware technology, computer capacity is still a limiting factor for CFD calculations to produce completely accurate results in the prediction of reactor internal flow. Therefore simplified geometries and turbulence models have to be used, and the computer capacity puts restrictions on the resolution in space and time. This leads to modeling errors and numerical errors that give more or less inaccurate results. In this paper a summary of the recommendations drawn from the analysis of the scale-down APR+ (Advanced Power Reactor Plus) internal flow are explained in the regulatory viewpoint. In this paper a summary of the recommendations for CFD simulation of reactor internal flow were explained in the regulatory viewpoint. Among them, an exact representation of the internal structures, especially located in the upstream of reactor core, may be the most important item for the accurate reactor internal flow simulation. To enhance the completeness of this study an additional CFD simulation to consider real geometry of reactor internal structures is on-going and the simulation results will be explained in the separate papers.

  14. How fine is fine enough when doing CFD terrain simulations

    DEFF Research Database (Denmark)

    Sørensen, Niels N.; Bechmann, Andreas; Réthoré, Pierre-Elouan;

    2012-01-01

    The present work addresses the problemof establishing the necessary grid resolution to obtain a given level of numerical accuracy using a CFD model for prediction of flow over terrain. It is illustrated, that a very high resolution may be needed if the numerical difference between consecutive...

  15. COMPARISON OF AXIAL FAN ROTOR EXPERIMENTAL DATA WITH CFD SIMULATION

    OpenAIRE

    Aleš Prachař

    2016-01-01

    Data obtained from an experimental simulation on a new test rig for axial fans are compared to a CFD simulation. The Edge solver is used and the development needed for the simulation (boundary conditions, free stream consistency) is described. Adequate agreement between the measured and calculated data is observed.

  16. CFD simulation of solids suspension in stirred tanks: Review

    Directory of Open Access Journals (Sweden)

    Ochieng Aoyi

    2010-01-01

    Full Text Available Many chemical reactions are carried out using stirred tanks, and the efficiency of such systems depends on the quality of mixing, which has been a subject of research for many years. For solid-liquid mixing, traditionally the research efforts were geared towards determining mixing features such as off-bottom solid suspension using experimental techniques. In a few studies that focused on the determination of solids concentration distribution, some methods that have been used have not been accurate enough to account for some small scale flow mal-distribution such as the existence of dead zones. The present review shows that computational fluid dynamic (CFD techniques can be used to simulate mixing features such as solids off-bottom suspension, solids concentration and particle size distribution and cloud height. Information on the effects of particle size and particle size distribution on the solids concentration distribution is still scarce. Advancement of the CFD modeling is towards coupling the physical and kinetic data to capture mixing and reaction at meso- and micro-scales. Solids residence time distribution is important for the design; however, the current CFD models do not predict this parameter. Some advances have been made in recent years to apply CFD simulation to systems that involve fermentation and anaerobic processes. In these systems, complex interaction between the biochemical process and the hydrodynamics is still not well understood. This is one of the areas that still need more attention.

  17. COMPARISON OF AXIAL FAN ROTOR EXPERIMENTAL DATA WITH CFD SIMULATION

    Directory of Open Access Journals (Sweden)

    Aleš Prachař

    2016-02-01

    Full Text Available Data obtained from an experimental simulation on a new test rig for axial fans are compared to a CFD simulation. The Edge solver is used and the development needed for the simulation (boundary conditions, free stream consistency is described. Adequate agreement between the measured and calculated data is observed.

  18. How fine is fine enough when doing CFD terrain simulations

    DEFF Research Database (Denmark)

    Sørensen, Niels N.; Bechmann, Andreas; Réthoré, Pierre-Elouan;

    The present work addresses the problem of establishing the necessary grid resolution to obtain a given level of numerical accuracy using a CFD model for prediction of flow over terrain. It is illustrated, that a very high resolution may be needed if the numerical difference between consecutive...

  19. Computational Fluid Dynamics (CFD) Technology Programme 1995- 1999

    Energy Technology Data Exchange (ETDEWEB)

    Haekkinen, R.J.; Hirsch, C.; Krause, E.; Kytoemaa, H.K. [eds.

    1997-12-31

    The report is a mid-term evaluation of the Computational Fluid Dynamics (CFD) Technology Programme started by Technology Development Centre Finland (TEKES) in 1995 as a five-year initiative to be concluded in 1999. The main goal of the programme is to increase the know-how and application of CFD in Finnish industry, to coordinate and thus provide a better basis for co-operation between national CFD activities and encouraging research laboratories and industry to establish co-operation with the international CFD community. The projects of the programme focus on the following areas: (1) studies of modeling the physics and dynamics of the behaviour of fluid material, (2) expressing the physical models in a numerical mode and developing a computer codes, (3) evaluating and testing current physical models and developing new ones, (4) developing new numerical algorithms, solvers, and pre- and post-processing software, and (5) applying the new computational tools to problems relevant to their ultimate industrial use. The report consists of two sections. The first considers issues concerning the whole programme and the second reviews each project

  20. CFD Simulations of Contaminant Transport between two Breathing Persons

    DEFF Research Database (Denmark)

    Bjørn, Erik; Nielsen, Peter V.

    Experiments have shown that exhalation from one person is able to penetrate the breathing zone of another person at a distance. Computational Fluid Dynamics (CFD) is used to investigate the dependency of the personal exposure on some physical parameters, namely: Pulmonary ventilation rate...

  1. Correlations between art and CFD through colour and shape

    Science.gov (United States)

    König, Carola S.

    2011-03-01

    Victorian stained glass artists were among the first to link vibrant colour with strong abstract geometry. This link was further exploited by artists of the early 20th century. Here may be mentioned the works of designers and artists like Mackintosh and of well-known Bauhaus group members like Klee and Kandinsky. Computational fluid dynamics (CFD) and art, particularly abstract art, are undoubtedly intrinsically linked not only by colour, but also by shape as often both contain regular geometries like rectangles and triangles. The use of colour has a multitude of functions in both the pre- and post-processing stages in CFD. These are discussed with an emphasis on the representation of CFD results. Moreover, modelling of fluid dynamics should be seen as but one example of numerical modelling in general. It may be that such common features between these very different metiers are the reason why the numerical modellers amongst us seem to have a natural liking for colourful abstract art. This paper investigates the correlations between art and CFD and is written from the view points of both the professional engineer and the hobby artist.

  2. Efficient Cfd/csd Coupling Methods for Aeroelastic Applications

    Science.gov (United States)

    Chen, Long; Xu, Tianhao; Xie, Jing

    2016-06-01

    A fast aeroelastic numerical simulation method using CFD/CSD coupling are developed. Generally, aeroelastic numerical simulation costs much time and significant hardware resources with CFD/CSD coupling. In this paper, dynamic grid method, full implicit scheme, parallel technology and improved coupling method are researched for efficiency simulation. An improved Delaunay graph mapping method is proposed for efficient dynamic grid deform. Hybrid grid finite volume method is used to solve unsteady flow fields. The dual time stepping method based on parallel implicit scheme is used in temporal discretization for efficiency simulation. An approximate system of linear equations is solved by the GMRES algorithm with a LU-SGS preconditioner. This method leads to a significant increase in performance over the explicit and LU-SGS implicit methods. A modification of LU-SGS is proposed to improve the parallel performance. Parallel computing overs a very effective way to improve our productivity in doing CFD/CFD coupling analysis. Improved loose coupling method is an efficiency way over the loose coupling method and tight coupling method. 3D wing's aeroelastic phenomenon is simulated by solving Reynolds-averaged Navier-Stokes equations using improved loose coupling method. The flutter boundary is calculated and agrees well with experimental data. The transonic hole is very clear in numerical simulation results.

  3. CFD Vision 2030 Study: A Path to Revolutionary Computational Aerosciences

    Science.gov (United States)

    Slotnick, Jeffrey; Khodadoust, Abdollah; Alonso, Juan; Darmofal, David; Gropp, William; Lurie, Elizabeth; Mavriplis, Dimitri

    2014-01-01

    This report documents the results of a study to address the long range, strategic planning required by NASA's Revolutionary Computational Aerosciences (RCA) program in the area of computational fluid dynamics (CFD), including future software and hardware requirements for High Performance Computing (HPC). Specifically, the "Vision 2030" CFD study is to provide a knowledge-based forecast of the future computational capabilities required for turbulent, transitional, and reacting flow simulations across a broad Mach number regime, and to lay the foundation for the development of a future framework and/or environment where physics-based, accurate predictions of complex turbulent flows, including flow separation, can be accomplished routinely and efficiently in cooperation with other physics-based simulations to enable multi-physics analysis and design. Specific technical requirements from the aerospace industrial and scientific communities were obtained to determine critical capability gaps, anticipated technical challenges, and impediments to achieving the target CFD capability in 2030. A preliminary development plan and roadmap were created to help focus investments in technology development to help achieve the CFD vision in 2030.

  4. A CFD/CSD interaction methodology for aircraft wings

    Science.gov (United States)

    Bhardwaj, Manoj Kumar

    With advanced subsonic transports and military aircraft operating in the transonic regime, it is becoming important to determine the effects of the coupling between aerodynamic loads and elastic forces. Since aeroelastic effects can contribute significantly to the design of these aircraft, there is a strong need in the aerospace industry to predict these aero-structure interactions computationally. To perform static aeroelastic analysis in the transonic regime, high fidelity computational fluid dynamics (CFD) analysis tools must be used in conjunction with high fidelity computational structural dynamics (CSD) analysis tools due to the nonlinear behavior of the aerodynamics in the transonic regime. There is also a need to be able to use a wide variety of CFD and CSD tools to predict these aeroelastic effects in the transonic regime. Because source codes are not always available, it is necessary to couple the CFD and CSD codes without alteration of the source codes. In this study, an aeroelastic coupling procedure is developed which will perform static aeroelastic analysis using any CFD and CSD code with little code integration. The aeroelastic coupling procedure is demonstrated on an F/A-18 Stabilator using NASTD (an in-house McDonnell Douglas CFD code) and NASTRAN. In addition, the Aeroelastic Research Wing (ARW-2) is used for demonstration of the aeroelastic coupling procedure by using ENSAERO (NASA Ames Research Center CFD code) and a finite element wing-box code (developed as a part of this research). The results obtained from the present study are compared with those available from an experimental study conducted at NASA Langley Research Center and a study conducted at NASA Ames Research Center using ENSAERO and modal superposition. The results compare well with experimental data. Parallel computing power is used to investigate parallel static aeroelastic analysis because obtaining an aeroelastic solution using CFD/CSD methods is computationally intensive. A

  5. CFD analysis of a diaphragm free-piston Stirling cryocooler

    Science.gov (United States)

    Caughley, Alan; Sellier, Mathieu; Gschwendtner, Michael; Tucker, Alan

    2016-10-01

    This paper presents a Computational Fluid Dynamics (CFD) analysis of a novel free-piston Stirling cryocooler that uses a pair of metal diaphragms to seal and suspend the displacer. The diaphragms allow the displacer to move without rubbing or moving seals. When coupled to a metal diaphragm pressure wave generator, the system produces a complete Stirling cryocooler with no rubbing parts in the working gas space. Initial modelling of this concept using the Sage modelling tool indicated the potential for a useful cryocooler. A proof-of-concept prototype was constructed and achieved cryogenic temperatures. A second prototype was designed and constructed using the experience gained from the first. The prototype produced 29 W of cooling at 77 K and reached a no-load temperature of 56 K. The diaphragm's large diameter and short stroke produces a significant radial component to the oscillating flow fields inside the cryocooler which were not modelled in the one-dimensional analysis tool Sage that was used to design the prototypes. Compared with standard pistons, the diaphragm geometry increases the gas-to-wall heat transfer due to the higher velocities and smaller hydraulic diameters. A Computational Fluid Dynamics (CFD) model of the cryocooler was constructed to understand the underlying fluid-dynamics and heat transfer mechanisms with the aim of further improving performance. The CFD modelling of the heat transfer in the radial flow fields created by the diaphragms shows the possibility of utilizing the flat geometry for heat transfer, reducing the need for, and the size of, expensive heat exchangers. This paper presents details of a CFD analysis used to model the flow and gas-to-wall heat transfer inside the second prototype cryocooler, including experimental validation of the CFD to produce a robust analysis.

  6. Coarse-grid-CFD. An advantageous alternative to subchannel analysis

    International Nuclear Information System (INIS)

    In the 1960th to 80th when current GEN II reactor technology was developed, the only possible approach was to use one-dimensional subchannel analysis to compute the flow inside a fuel bundle so that the subchannel scale could be resolved. For simulations of the whole reactor core either system codes or homogenization were employed. In system codes resolution of individual assemblies was the state of the art. Homogenization used porous media equations simulations and averaged the thermohydraulics on reactor core scale. Current potent computing power allows using Computational Fluid Dynamics (CFD) to simulate individual fuel assemblies. Yet the large number of fuel assemblies within the core forbids exploiting CFD for core wide simulation. We propose to combine ideas of subchannel analysis and CFD to develop a new methodology which takes advantage of the fast development of commercial CFD software and the efficiency of subchannel analysis. In this methodology was first applied to simulate a wire-wrap fuel bundle of the High Performance Light Water Reactor (HPLWR). Computations using an inviscid Euler solver on an extremely coarse grid were tuned to predict the true thermohydraulics by adding volumetric forces. These forces represent the non-resolved sub-grid physics. The volumetric forces cannot be measured directly. However, they can be accessed from detailed CFD simulations resolving all relevant physics. Parameterization of these subgrid forces can be realized analogous to models in subchannel codes. In the present work we extend the methodology to the open source solver OpenFOAM and a specific hexagonal fuel assembly which is studied in the framework of liquid metal cooled GEN IV reactor concepts. (orig.)

  7. CFD characterization of flow regimes inside open cell foam substrates

    International Nuclear Information System (INIS)

    Highlights: • We investigated the pressure drop in open-cell foams. • The study is based on a combination of micro-CT, image-based modeling and CFD tools. • Detailed CFD simulations were applied for the investigation of turbulent flow regimes. • The effects of geometrical parameters are studied by means of RANS CFD simulations. • Results are analyzed in terms of non-dimensional parameters. - Abstract: In this work a combination of micro-CT, image-based modeling and CFD has been applied to investigate the pressure drop in open-cell foams. The analysis covers a range of flow regimes and is aimed at determining the effects of important morphological parameters on the pressure drop. The adoption of micro-CT technology along with detailed CFD modeling allows the investigation of phenomena occurring in real foam micro-structures. Moreover, by means of image processing tools, the geometry can be artificially modified in order to investigate the effects of mathematical transformation of the geometrical parameters of a real foam, one parameter at a time, e.g. varying pore size without affecting the porosity. Non-dimensional coefficients have been defined for the analysis of the results, with the purpose of describing the pressure drop as a function of the Reynolds number. The proposed formulation allows us to relate the permeability properties of an open-cell foam to its morphology alone, without any dependence on the properties of the fluid adopted or on the effective characteristic dimension of the foam micro-structure (pore or cell size). Comparison with experimental results available in the literature is also provided for one of the cases studied

  8. Thermal hydraulic simulations, error estimation and parameter sensitivity studies in Drekar::CFD

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Thomas Michael; Shadid, John N; Pawlowski, Roger P; Cyr, Eric C; Wildey, Timothy Michael

    2014-01-01

    This report describes work directed towards completion of the Thermal Hydraulics Methods (THM) CFD Level 3 Milestone THM.CFD.P7.05 for the Consortium for Advanced Simulation of Light Water Reactors (CASL) Nuclear Hub effort. The focus of this milestone was to demonstrate the thermal hydraulics and adjoint based error estimation and parameter sensitivity capabilities in the CFD code called Drekar::CFD. This milestone builds upon the capabilities demonstrated in three earlier milestones; THM.CFD.P4.02 [12], completed March, 31, 2012, THM.CFD.P5.01 [15] completed June 30, 2012 and THM.CFD.P5.01 [11] completed on October 31, 2012.

  9. REDUCCIÓN DE LA BIOMASA DEL PINO CARRASCO (PINUS HALEPENSIS EN UN ÁREA DEL SURESTE SEMIÁRIDO PENINSULAR COMO ESTRATEGIA PARA EVITAR EL ESTRÉS HÍDRICO

    Directory of Open Access Journals (Sweden)

    Francisco Belmonte Serrato

    2008-01-01

    Full Text Available En las épocas de fuertes sequías, la vegetación mediterránea sufre un estado de estrés hídrico prolongado que le obliga a adoptar diversas estrategias de supervivencia, entre las que fi guran, como último recurso, y antes de llegar a superar su capacidad de resilencia, la reducción de la biomasa de hojas. En este trabajo se pone de manifi esto como algunos ejemplares de Pinus halepensis existentes en el área de estudio (el campo experimental de El Ardal, Murcia, redujeron apreciablemente su biomasa aérea en respuesta a la sequía, que se manifestó en un importante aumento de la producción de hojarasca. La producción de hojarasca se relaciona además de con la precipitación registrada en el periodo de estudio, con la humedad del suelo, parámetro clave en la supervivencia de la vegetación en ambientes secos.

  10. Cálculo de estructuras utilizando elemento finito con cómputo en paralelo

    OpenAIRE

    Vargas Félix, José Miguel

    2010-01-01

    Nuestro trabajo trata sobre la solución numérica de problemas de deformación lineal de sólidos por medio del método de elementos finitos, estos problemas se resuelven utilizando estratégias de cómputo en paralelo. Hablamos sobre algunas formas de paralelizar los algoritmos, tanto utilizando modelos de memoria compartida como de memoria distribuída. En particular nos centraremos en la descomposición de dominios usando el método alternante de Schwarz para resolver problemas de elemento finito c...

  11. CFD application to advanced design for high efficiency spacer grid

    International Nuclear Information System (INIS)

    Highlights: • A new LDV was developed to investigate the local velocity in a rod bundle and inside a spacer grid. • The design information that utilizes for high efficiency spacer grid has been obtained. • CFD methodology that predicts flow field in a PWR fuel has been developed. • The high efficiency spacer grid was designed using the CFD methodology. - Abstract: Pressurized water reactor (PWR) fuels have been developed to meet the needs of the market. A spacer grid is a key component to improve thermal hydraulic performance of a PWR fuel assembly. Mixing structures (vanes) of a spacer grid promote coolant mixing and enhance heat removal from fuel rods. A larger mixing vane would improve mixing effect, which would increase the departure from nucleate boiling (DNB) benefit for fuel. However, the increased pressure loss at large mixing vanes would reduce the coolant flow at the mixed fuel core, which would reduce the DNB margin. The solution is to develop a spacer grid whose pressure loss is equal to or less than the current spacer grid and that has higher critical heat flux (CHF) performance. For this reason, a requirement of design tool for predicting the pressure loss and CHF performance of spacer grids has been increased. The author and co-workers have been worked for development of high efficiency spacer grid using Computational Fluid Dynamics (CFD) for nearly 20 years. A new laser Doppler velocimetry (LDV), which is miniaturized with fiber optics embedded in a fuel cladding, was developed to investigate the local velocity profile in a rod bundle and inside a spacer grid. The rod-embedded fiber LDV (rod LDV) can be inserted in an arbitrary grid cell instead of a fuel rod, and has the advantage of not disturbing the flow field since it is the same shape as a fuel rod. The probe volume of the rod LDV is small enough to measure spatial velocity profile in a rod gap and inside a spacer grid. According to benchmark experiments such as flow velocity

  12. Effect of variety and cane yield on sugarcane potential trash Efecto de las variedades y su rendimiento cultural en la biomasa residual potencial

    Directory of Open Access Journals (Sweden)

    Eduardo R. Romero

    , conservando el suelo y ofreciendo una posibilidad para la generación de energía. Una estimación del potencial de residuos disponible de la caña de azúcar cobra gran relevancia en el momento de definir estrategias de manejo. Se realizó un estudio para determinar la cantidad de biomasa residual disponible en los cañaverales en forma previa (SPT y posterior (SFT a la cosecha mecanizada en verde para las principales variedades cultivadas en la provincia de Tucumán (LCP 85-384, TUCCP 77-42, CP 65-357 y RA 87-3. Además, se estudió la relación entre SPT y SFT a fin de validar la precisión de SPT como predictor de SFT en el caso de la cosecha integral en verde. El incremento del SPT estuvo asociado al mayor rendimiento cultural/ha, registrándose valores del 6,9 a 16,0 t/ha de biomasa residual para rendimientos culturales de 32 a 104 t/ha. LCP 85-384 y CP 65-357 produjeron el mayor SPT, mientras que TUCCP 77-42 generó la menor cantidad para niveles similares de rendimiento cultural. La relación SPT/CY disminuyó y el promedio general fue del 16% del rendimiento cultural, aunque su uso para estimar SPT fue limitado, como señalan los bajos coeficientes de determinación. SPT predijo adecuadamente SFT para el caso de la cosecha integral en verde, y el primero puede ser estimado adecuadamente empleando el rendimiento cultural/ha.

  13. The design of modern gas turbine design : beyond CFD

    Energy Technology Data Exchange (ETDEWEB)

    Kenny, D.P. [Pratt and Whitney Canada, Longueuil, PQ (Canada)

    1998-09-01

    The progress that has been made in recent years of applying computational fluid dynamics (CFD) to the design of advanced turbine engines was discussed. Pratt and Whitney has successfully transitioned the design of the company`s advanced turbine engines from a five-year design cycle based on a succession of design-test-redesign cycles to a three-year design cycle based on an analytical design methodology. The development of 3-D viscous CFD and computational structural mechanics (CSM) codes as primary design tools and a multi-disciplinary approach to applications have been major factors in achieving this success. The company also made significant progress in the development of a fully implicit unsteady stage scheme, with marked impact on performance and durability. Improvements also have been made in the life of the hot end components and in aero-acoustics. 9 figs.

  14. Gasification CFD Modeling for Advanced Power Plant Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Zitney, S.E.; Guenther, C.P.

    2005-09-01

    In this paper we have described recent progress on developing CFD models for two commercial-scale gasifiers, including a two-stage, coal slurry-fed, oxygen-blown, pressurized, entrained-flow gasifier and a scaled-up design of the PSDF transport gasifier. Also highlighted was NETL’s Advanced Process Engineering Co-Simulator for coupling high-fidelity equipment models with process simulation for the design, analysis, and optimization of advanced power plants. Using APECS, we have coupled the entrained-flow gasifier CFD model into a coal-fired, gasification-based FutureGen power and hydrogen production plant. The results for the FutureGen co-simulation illustrate how the APECS technology can help engineers better understand and optimize gasifier fluid dynamics and related phenomena that impact overall power plant performance.

  15. Performance evaluation of a thermosyphon heat transport device using CFD

    International Nuclear Information System (INIS)

    Study of the heat transfer characteristics of a Thermosyphon heat transport device, which can be employed for passive heat transfer, is taken up in the present paper. In the present work, a thermosyphon heat transport device designed at BARC is being considered for its performance evaluation. A CFD model was prepared and parametric studies have been conducted to determine the heat transport capacity of the device. Different parameters considered for parametric studies are hot fluid temperature, heated length and sleeve length. The frictional pressure drop inside the device is calculated empirically also and validated against the CFD results. The paper presents the results of the studies carried out with Lead-Bismuth eutectic as the working fluid. (author)

  16. CFD Application in Implantable Rotary Blood Pump Design and Validation

    Institute of Scientific and Technical Information of China (English)

    YI Qian

    2004-01-01

    Implantable rotary blood pump (IRBP) has been promoted to the stage of clinical trial. This paper introduces a unique IRBP without a shaft. Instead of using thrombogenic pivots or power-drawing magnetic suspension, impeller is supported hydrodynamically when rotating, by lubrication flows in the thin spaces between itself and the pump body. To this end, the flow is very difficult to be measured using usual laboratory equipments. Therefore, computational fluid dynamics (CFD) has been applied as an important tool in the IRBP design and its validation procedure. Several CFD results such as pump performance improvement, unsteady hydraulic dynamic analysis, biocapability prediction, validation and verification (V&V), and flow visualization have been performed.

  17. CFD Application in Implantable Rotary Blood Pump Design and Validation

    Institute of Scientific and Technical Information of China (English)

    YIQian

    2004-01-01

    Implantable rotary blood pump (IRBP) has been promoted to the stage of clinical trial. This paper introduces a unique IRBP without a.shaft. Instead of using thrombogenic pivots or power-drawing magnetic suspension, impeller is supported hydrodynamically when rotating, by lubrication flows in the thin spaces between itself and the pump body. To this end, the flow is very difficult to be measured using usual laboratory equipments. Therefore, computational fluid dynamics (CFD) has been applied as an important tool in the IRBP design and its validation procedure. Several CFD results such as pump performance improvement, unsteady hydraulic dynamic analysis, biocapability prediction, validation and verification (V&V), and flow visualization have been performed.

  18. CFD Data Sets on the WWW for Education and Testing

    Science.gov (United States)

    Globus, Al; Lasinski, T. A. (Technical Monitor)

    1995-01-01

    The Numerical Aerodynamic Simulation (NAS) Systems Division at NASA Ames Research Center has begun the development of a Computational Fluid Dynamics (CFD) data set archive on the World Wide Web (WWW) at URL http://www.nas.nasa.gov/NAS/DataSets/. Data sets are integrated with related information such as research papers, metadata, visualizations, etc. In this paper, four classes of users are identified and discussed: students, visualization developers, CFD practitioners, and management. Bandwidth and security issues are briefly reviewed and the status of the archive as of May 1995 is examined. Routine network distribution of data sets is likely to have profound implications for the conduct of science. The exact nature of these changes is subject to speculation, but the ability for anyone to examine the data, in addition to the investigator's analysis, may well play an important role in the future.

  19. Design and Analysis of Missile Systems through CFD Simulations

    Science.gov (United States)

    Chakraborty, Debasis

    2010-10-01

    Development of indigenous CFD codes and their applications for complex aerodynamic and propulsive flow problems pertaining to DRDO missiles are presented. Grid generators, 3D Euler and Navier Stokes solvers are developed in-house using state of art numerical techniques and physical models. These softwares are used extensively for aerodynamic characterization of missiles over a wide range of Mach number, angle of attack, control surface deflection and store separation studies. Significant contributions are made in the design of high speed propulsion systems of various ongoing and future missiles through CFD analysis internal flow field. Important design modifications were suggested and the propulsion system performances were optimized. Capabilities have been developed for many advanced topics including computational aeroelasticity, coupled Euler Boltzmann solver, etc.

  20. Experimental and CFD investigation of gas phase freeboard combustion

    DEFF Research Database (Denmark)

    Andersen, Jimmy

    , but under well-defined conditions. Comprehensive experimental data for velocity field, temperatures, and gas composition are obtained from a 50 kW axisymmetric non-swirling natural gas fired combustion setup under two different settings. Ammonia is added to the combustion setup in order to simulate fuel......Reliable and accurate modeling capabilities for combustion systems are valuable tools for optimization of the combustion process. This work concerns primary precautions for reducing NO emissions, thereby abating the detrimental effects known as “acid rain”, and minimizing cost for flue gas...... treatment. The aim of this project is to provide validation data for Computational Fluid Dynamic (CFD) models relevant for grate firing combustion conditions. CFD modeling is a mathematical tool capable of predicting fluid flow, mixing and chemical reaction with thermal conversion and transport. Prediction...

  1. CFD simulations of a spouted bed equipment for particle coating

    Energy Technology Data Exchange (ETDEWEB)

    Wolff Filho, Germano Klaus; Cabral, Paulo Alexandre de Moraes [Centro Tecnologico do Exercito (CTEx-RJ), Rio de Janeiro, RJ (Brazil)]. E-mails: klauswolff@ctex.eb.br; paulo@ctex.eb.br

    2007-07-01

    Due to their solids circulation characteristics and excellent gas-particle contact, spouted beds have been used in several engineering applications, including nuclear fuel particles coatings. A laboratory scale equipment was mounted, aiming particles coating for use in nuclear fuel research. The line operates with a spouted bed reactor filled with particles on whose surface the deposition process happens. Some computational simulations, using the CFD commercial code PHOENICS{sup R} , were made in order to show some of the equipment possibilities and limitations. It's important to exhaust theoretical investigations about this kind of system, because experimental conditions seem to be dangerous, beyond associated difficulties in process control and operation. In this work, CFD simulations are used to obtain patterns of solids and gas flows. (author)

  2. Considering value of information when using CFD in design

    Energy Technology Data Exchange (ETDEWEB)

    Misra, John Satprim [Iowa State Univ., Ames, IA (United States)

    2009-01-01

    This thesis presents an approach to find lower resolution CFD models that can accurately lead a designer to a correct decision at a lower computational cost. High-fidelity CFD models often contain too much information and come at a higher computational cost, limiting the designs a designer can test and how much optimization can be performed on the design. Lower model resolution is commonly used to reduce computational time. However there are no clear guidelines on how much model accuracy is required. Instead experience and intuition are used to select an appropriate lower resolution model. This thesis presents an alternative to this ad hoc method by considering the added value of the addition information provided by increasing accurate and more computationally expensive models.

  3. CFD Simulations of Joint Urban Atmospheric Dispersion Field Study

    Energy Technology Data Exchange (ETDEWEB)

    Lee, R; Humphreys III, T; Chan, S

    2004-06-17

    The application of Computational Fluid Dynamics (CFD) to the understanding of urban wind flow and dispersion processes has gained increasing attention over recent years. While many of the simpler dispersion models are based on a set of prescribed meteorology to calculate dispersion, the CFD approach has the ability of coupling the wind field to dispersion processes. This has distinct advantages when very detailed results are required, such as for the case where the releases occur around buildings and within urban areas. CFD also has great flexibility as a testbed for turbulence models, which has important implications for atmospheric dispersion problems. In the spring of 2003, a series of dispersion field experiments (Joint Urban 2003) were conducted at Oklahoma City (Allwine, et. al, 2004). These experiments were complimentary to the URBAN 2000 field studies at Salt Lake City (Shinn, et. al, 2000) in that they will provide a second set of comprehensive field data for evaluation of CFD as well as for other dispersion models. In contrast to the URBAN 2000 experiments that were conducted entirely at night, these new field studies took place during both daytime and nighttime thus including the possibility of convective as well as stable atmospheric conditions. Initially several CFD modeling studies were performed to provide guidance for the experimental team in the selection of release sites and in the deployment of wind and concentration sensors. Also, while meteorological and concentration measurements were taken over the greater Oklahoma City urban area, our CFD calculations were focused on the near field of the release point. The proximity of the source to a large commercial building and to the neighboring buildings several of which have multistories, present a significant challenge even for CFD calculations involving grid resolutions as fine as 1 meter. A total of 10 Intensive Observations Periods (IOP's) were conducted within the 2003 field experiments. SF6

  4. Dynamic Analysis and CFD Numerical Simulation on Backpressure Filling System

    Directory of Open Access Journals (Sweden)

    Jing Qian

    2015-01-01

    Full Text Available A backpressure filling system is a kind of air type filling system which could be applied to power type, fine or coarse grain, or mixtures with fine and coarse components. The working principle of backpressure filling system was discussed based on fundamental hydromechanics. The research limit values of backpressure were achieved via mechanical analysis. Comparing with the exit velocity of material by theoretical analysis and numerical simulation, the CFD simulation model was confirmed and its related parameters were determined. The CFD numerical simulation shows the relationship between production capacity of packaging machine and backpressure, and the results matched actual operation of the equipment well. Combining with the demand of device capacity, the range of backpressure could be controlled at 8 kPa~11 kPa.

  5. Indoor Airflow Simulation inside Lecture Room: A CFD Approach

    Science.gov (United States)

    Lin, S.; Tee, B. T.; Tan, C. F.

    2015-09-01

    Indoor air flow distribution is important as it will affect the productivity of the occupants. Poor air flow distribution not only cause discomfort to the occupants but also influence their ability to conduct their activities. The main purpose of this study is to investigate the indoor air flow inside lecture rooms through CFD simulation approach. Two types of air-conditioning configuration system in lecture rooms have been selected for this study which includes the split unit and centralized system. The air flow distribution between these two systems are analyzed and compared. Physical measurement is conducted using a velocity meter for validation purpose. CFD simulation is developed by using ANSYS Fluent software. The results specifically the air velocity and temperature data are compared and validated. Based on the findings, design recommendation is proposed with the aim to improve on the current air flow distribution in the lecture rooms.

  6. Modeling and verification of hemispherical solar still using ANSYS CFD

    Energy Technology Data Exchange (ETDEWEB)

    Panchal, Hitesh N. [KSV University, Gujarat Power Engineering and Research Institute, Mehsana (India); Shah, P.K. [Silver Oak College of Engineering and Technology, Ahmedabad, Gujarat (India)

    2013-07-01

    In every efficient solar still design, water temperature, vapor temperature and distillate output, and difference between water temperature and inner glass cover temperatures are very important. Here, two dimensional three phase model of hemispherical solar still is made for evaporation as well as condensation process in ANSYS CFD. Simulation results like water temperature, vapor temperature, distillate output compared with actual experimental results of climate conditions of Mehsana (latitude of 23° 59’ and longitude of 72° 38) of hemispherical solar still. Water temperature and distillate output were good agreement with actual experimental results. Study shows that ANSYS-CFD is very powerful as well as efficient tool for design, comparison purpose of hemispherical solar still.

  7. The legacy and future of CFD at Los Alamos

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, N.L. [Los Alamos National Lab., NM (United States). Theoretical Div.

    1996-06-01

    The early history is presented of the prolific development of CFD methods in the Fluid Dynamics Group (T-3) at Los Alamos National Laboratory in the years from 1958 to the late 1960`s. Many of the currently used numerical methods--PIC, MAC, vorticity-stream-function, ICE, ALE methods and the {kappa}-{var_epsilon} method for turbulence--originated during this time. The rest of the paper summarizes the current research in T-3 for CFD, turbulence and solids modeling. The research areas include reactive flows, multimaterial flows, multiphase flows and flows with spatial discontinuities. Also summarized are modern particle methods and techniques developed for large scale computing on massively parallel computing platforms and distributed processors.

  8. Design of ETO Propulsion Turbine Using CFD Analyses

    Science.gov (United States)

    Dejong, F. J.; Chan, Y. T.; Gibeling, H. J.

    1995-01-01

    As one of the activities of the NASA/MSFC Turbine Technology Team, the present effort focused on using CFD in the design and analysis of high performance rocket engine pumps. A three-dimensional Navier-Stokes code was used for various turbine flow field calculations, with emphasis on the tip clearance flow and the associated losses. Both a baseline geometry and an advanced-concept geometry (with a mini-shroud at the blade tip) were studied at several tip clearances. The calculations performed under the present effort demonstrate that a state-of-the-art CFD code can be applied successfully to turbine design and the development of advanced hardware concepts.

  9. Accuracy, convergence and stability of finite element CFD algorithms

    International Nuclear Information System (INIS)

    The requirement for artificial dissipation is well understood for shock-capturing CFD procedures in aerodynamics. However, numerical diffusion is widely utilized across the board in Navier-Stokes CFD algorithms, ranging from incompressible through supersonic flow applications. The Taylor weak statement (TWS) theory is applicable to any conservation law system containing an evolutionary component, wherein the analytical modifications becomes functionally dependent on the Jacobian of the corresponding equation system flux vector. The TWS algorithm is developed for a range of fluid mechanics conservation law systems including incompressible Navier-Stokes, depth-averaged free surface hydrodynamic Navier-Stokes, and the compressible Euler and Navier-Stokes equations. This paper presents the TWS statement for the problem class range and highlights the important theoretical issues of accuracy, convergence and stability. Numerical results for a variety of benchmark problems are presented to document key features. 8 refs

  10. CFD simulation of coal and straw co-firing

    DEFF Research Database (Denmark)

    Junker, Helle; Hvid, Søren L.; Larsen, Ejvind;

    This paper presents the results of a major R&D program with the objective to develop CFD based tools to assess the impact of biomass co-firing in suspension fired pulverized coal power plants. The models have been developed through a series of Danish research projects with the overall objective...... emissions. Results are presented for a Danish full-scale boiler that is currently co-firing biomass with coal on a commercial basis....

  11. CFD Modeling in Development of Renewable Energy Applications

    Directory of Open Access Journals (Sweden)

    Maher A.R. Sadiq Al-Baghdadi

    2013-01-01

    Full Text Available Chapter 1: A Multi-fluid Model to Simulate Heat and Mass Transfer in a PEM Fuel Cell. Torsten Berning, Madeleine Odgaard, Søren K. Kær Chapter 2: CFD Modeling of a Planar Solid Oxide Fuel Cell (SOFC for Clean Power Generation. Meng Ni Chapter 3: Hydrodynamics and Hydropower in the New Paradigm for a Sustainable Engineering. Helena M. Ramos, Petra A. López-Jiménez Chapter 4: Opportunities for CFD in Ejector Solar Cooling. M. Dennis Chapter 5: Three Dimensional Modelling of Flow Field Around a Horizontal Axis Wind Turbine (HAWT. Chaouki Ghenai, Armen Sargsyan, Isam Janajreh Chapter 6: Scaling Rules for Hydrodynamics and Heat Transfer in Jetting Fluidized-Bed Biomass Gasifiers. K. Zhang, J. Chang, P. Pei, H. Chen, Y. Yang Chapter 7: Investigation of Low Reynolds Number Unsteady Flow around Airfoils in Pitching, Plunging and Flapping Motions. M.R. Amiralaei, H. Alighanbari, S.M. Hashemi Chapter 8: Justification of Computational Fluid Dynamics Simulation for Flat Plate Solar Energy Collector. Mohamed Selmi, Mohammed J. Al-Khawaja, Abdulhamid Marafia Chapter 9: Comparative Performance of a 3-Bladed Airfoil Chord H-Darrieus and a 3-Bladed Straight Chord H-Darrieus Turbines using CFD. R. Gupta, Agnimitra Biswas Chapter 10: Computational Fluid Dynamics for PEM Fuel Cell Modelling. A. Iranzo, F. Rosa Chapter 11: Analysis of the Performance of PEM Fuel Cells: Tutorial of Major Functional and Constructive Characteristics using CFD Analysis. P.J. Costa Branco, J.A. Dente Chapter 12: Application of Techniques of Computational Fluid Dynamics in the Design of Bipolar Plates for PEM Fuel Cells. A.P. Manso, F.F. Marzo, J. Barranco, M. Garmendia Mujika.

  12. Optimize Sedimentation Tank and Lab Flocculation Unit by CFD

    OpenAIRE

    Zhang, Duo

    2014-01-01

    This work aim at introduce basic knowledge of CFD and it’s application in optimization of sedimentation tank and lab flocculation units. A series of specialized strategies are developed for the simulation of the sedimentation tanks and lab flocculation units. Chapter 1 is general introduction of particle removal in water and wastewater treatment, includes particle separation, as well as particle removal during chemical treatment and biological treatment. In chapter 2, background and appli...

  13. CFD Studies on Multi Lead Rifled [MLR] Boiler Tubes

    OpenAIRE

    Dr T C Mohankumar

    2013-01-01

    This paper reports the merits of multi lead rifled [MLR] tubes in vertical water tube boiler using CFD tool. Heat transfer enhancement of MLR tubes was mainly taken in to consideration. Performance of multi lead rifled tube was studied by varying its influencing geometrical parameter like number of rifling, height of rifling, length of pitch of rifling for a particular length. The heat transfer analysis was done at operating conditions of an actual coal fired water tube boiler situated at Apo...

  14. CFD Analysis of Bubbling Fluidized Bed Using Rice Husk

    Science.gov (United States)

    Singh, Ravi Inder; Mohapatra, S. K.; Gangacharyulu, D.

    Rice is Cultivated in all the main regions of world. The worldwide annual rice production could be 666million tons (www.monstersandcritics.com,2008) for year 2008. The annual production of rice husk is 133.2 million tons considering rice husk being 20% of total paddy production. The average annual energy potential is 1.998 *1012 MJ of rice husk considering 15MJ/kg of rice husk. India has vast resource of rice husk; a renewable source of fuel, which if used effectively would reduce the rate of depletion of fossil energy resources. As a result a new thrust on research and development in boilers bases on rice husk is given to commercialize the concept. CFD is the analysis of systems involving fluid flow, heat transfer and associated phenomena such as chemical reactions by means of computer-based simulation. High quality Computational Fluid dynamics (CFD) is an effective engineering tool for Power Engineering Industry. It can determine detailed flow distributions, temperatures, and pollutant concentrations with excellent accuracy, and without excessive effort by the software user. In the other words it is the science of predicting fluid flow, heat and mass transfer, chemical reactions and related phenomena; and an innovate strategy to conform to regulations and yet stay ahead in today's competitive power market. This paper is divided into two parts; in first part review of CFD applied to the various types of boilers based on biomass fuels/alternative fuels is presented. In second part CFD analysis of fluidized bed boilers based on rice husk considering the rice husk based furnace has been discussed. The eulerian multiphase model has used for fluidized bed. Fluidized bed has been modeled using Fluent 6.2 commercial code. The effect of numerical influence of bed superheater tubes has also been discussed.

  15. CFD APPROACH FOR FLOW CHARACTERISTICS OF HYDRAULIC FRANCIS TURBINE

    OpenAIRE

    RUCHI KHARE,; DR. VISHNU PRASAD,; RUCHI KHARE, DR. VISHNU PRASAD,

    2010-01-01

    With the growth of computational mechanics, the virtual hydraulic machines are becoming more and more realistic to get minor details of the flow, which are not possible in model testing. In present work, 3D turbulent real flow analyses in hydraulic Francis turbine have been carried out at three guide vane opening and different rotation speed using Ansys CFX computational fluid dynamics (CFD) software. The average values of flow parameters like velocities and flow angles at the inlet and outle...

  16. Hypersonic Intake Starting Characteristics–A CFD Validation Study

    OpenAIRE

    Soumyajit Saha; Debasis Chakraborty

    2012-01-01

    Numerical simulation of hypersonic intake starting characteristics is presented. Three dimensional RANS equations are solved alongwith SST turbulence model using commercial computational fluid dynamics (CFD) software. Wall pressure distribution and intake performance parameters are found to match well with experimental data for different free stream Mach number in the range of 3-8. The unstarting of the intake is traced from the sudden drop of mass capture ratio. Wall condition (adiabatic or ...

  17. A CFD STUDY OF CAVITATION IN REAL SIZE DIESEL INJECTORS

    OpenAIRE

    PATOUNA, STAVROULA

    2012-01-01

    In Diesel engines, the internal flow characteristics in the fuel injection nozzles, such as the turbulence level and distribution, the cavitation pattern and the velocity profile affect significantly the air-fuel mixture in the spray and subsequently the combustion process. Since the possibility to observe experimentally and measure the flow inside real size Diesel injectors is very limited, Computational Fluid Dynamics (CFD) calculations are generally used to obtain the relevant informati...

  18. CFD simulation of vented explosion and turbulent flame propagation

    Directory of Open Access Journals (Sweden)

    Tulach Aleš

    2015-01-01

    Full Text Available Very rapid physical and chemical processes during the explosion require both quality and quantity of detection devices. CFD numerical simulations are suitable instruments for more detailed determination of explosion parameters. The paper deals with mathematical modelling of vented explosion and turbulent flame spread with use of ANSYS Fluent software. The paper is focused on verification of preciseness of calculations comparing calculated data with the results obtained in realised experiments in the explosion chamber.

  19. 3D CFD Simulation von Turboladern innerhalb einer Motorumgebung

    OpenAIRE

    Boose, Benjamin

    2014-01-01

    Im Rahmen dieser Forschungsarbeit wird das Verhalten mehrflutiger Abgasturbolader innerhalb einer Motorumgebung mit pulsierenden Randbedingungen in verschiedenen Motorbetriebspunkten mittels eines CFD Ansatzes untersucht. Dazu wird ein vollständiges dreidimensionales Strömungsmodell eines asymmetrischen Zwillingsstromturboladers aufgebaut, beginnend bei den Abgaskrümmern über die Turbinen- und Verdichtergehäuse inklusive der kompletten Laufräder bis hin zum Vorkatalysator. Die Eintrittsran...

  20. CFD Simulation of a Natural Circulation Helium Loop

    OpenAIRE

    Knížat Branislav; Hlbočan Peter; Mlkvik Marek

    2015-01-01

    The paper deals with a flow in a closed helium loop serving for cooling of a fast reactor. The flow in pipeline branches of the system is simulated by methods of CFD. The purpose is to find exact values of pressure losses, so that heat exchangers could be successfully designed and so that the power available for a loop drive could be optimally utilized. General approach to the simulation is presented, as well as the calculation procedure and achieved results.

  1. CFD simulation of vented explosion and turbulent flame propagation

    OpenAIRE

    Tulach Aleš; Mynarz Miroslav; Kozubková Milada

    2015-01-01

    Very rapid physical and chemical processes during the explosion require both quality and quantity of detection devices. CFD numerical simulations are suitable instruments for more detailed determination of explosion parameters. The paper deals with mathematical modelling of vented explosion and turbulent flame spread with use of ANSYS Fluent software. The paper is focused on verification of preciseness of calculations comparing calculated data with the results obtained in realised experiments...

  2. CFD simulation of the discharge flow from standard Rushton impeller

    OpenAIRE

    Bohuš Kysela; Jiří Konfršt; Ivan Fořt; Zdeněk Chára

    2014-01-01

    The radial discharge jet from the standard Rushton turbine was investigated by the CFD calculations and compared with results from the Laser Doppler Anemometry (LDA) measurements. The Large Eddy Simulation (LES) approach was employed with Sliding Mesh (SM) model of the impeller motion. The obtained velocity profiles of the mean ensemble-averaged velocity and r.m.s. values of the fluctuating velocity were compared in several distances from the impeller blades. The calculated values of mean ens...

  3. CFD Simulation of a Natural Circulation Helium Loop

    Directory of Open Access Journals (Sweden)

    Knížat Branislav

    2015-12-01

    Full Text Available The paper deals with a flow in a closed helium loop serving for cooling of a fast reactor. The flow in pipeline branches of the system is simulated by methods of CFD. The purpose is to find exact values of pressure losses, so that heat exchangers could be successfully designed and so that the power available for a loop drive could be optimally utilized. General approach to the simulation is presented, as well as the calculation procedure and achieved results.

  4. CFD Simulation of Nanosufur Crystallization Incorporating Population Balance Modeling

    OpenAIRE

    Fatemeh Golkhou; Mahmod Tajee Hamed Mosavian

    2013-01-01

    A physical vapor condensation process for synthesizing nanosized sulfur powder as a precursor for various industries was simulated by the use of computational ?uid dynamic (CFD) modeling. The phase change, swirl flow and heat transfer taking place inside the cyclone are analyzed along with particle formation via gas condensation method. The population balance model is a mathematical framework for the modeling of crystal size distribution (CSD) and the study of gas-phase changes leading to nuc...

  5. Wind energy; CFD simulation of wakes and wind turbine forces

    OpenAIRE

    Fredriksen, Tommy

    2015-01-01

    Wind power is a clean and renewable energy source, which plays an important role in the world’s energy landscape. When developing a wind farm it is beneficial to analyze the flow pattern in order to maximize the total performance of the wind farm, it is also important to predict wake patterns to prevent structural damage on downstream turbines. Traditional fully detailed CFD models will be very computational heavy to utilize for such analysis. In order to perform an analysis with ...

  6. Dynamic Analysis and CFD Numerical Simulation on Backpressure Filling System

    OpenAIRE

    Jing Qian; Lu, J. P.; Hui, S L; Ma, Y J; D. Y. Li

    2015-01-01

    A backpressure filling system is a kind of air type filling system which could be applied to power type, fine or coarse grain, or mixtures with fine and coarse components. The working principle of backpressure filling system was discussed based on fundamental hydromechanics. The research limit values of backpressure were achieved via mechanical analysis. Comparing with the exit velocity of material by theoretical analysis and numerical simulation, the CFD simulation model was confirmed and it...

  7. CFD Simulation Evaluation for Flow Distribution of the Closed Chamber

    OpenAIRE

    Hong Bin; Wang Hongmei

    2016-01-01

    Taking a closed chamber flow field as object, this paper establishes the 3D model of the Closed Chamber. With the conclusion of flow distribution and gasoline vapor concentration distribution of the Closed Chamber reached via the CFD software of Fluent and experiment research, this paper analyzes the flow distribution and concentration distribution of gasoline vapor. Several improvement projects are proposed, such as improving the wind circulation system to optimize the indoor gas concentrati...

  8. CFD simulation of vented explosion and turbulent flame propagation

    Science.gov (United States)

    Tulach, Aleš; Mynarz, Miroslav; Kozubková, Milada

    2015-05-01

    Very rapid physical and chemical processes during the explosion require both quality and quantity of detection devices. CFD numerical simulations are suitable instruments for more detailed determination of explosion parameters. The paper deals with mathematical modelling of vented explosion and turbulent flame spread with use of ANSYS Fluent software. The paper is focused on verification of preciseness of calculations comparing calculated data with the results obtained in realised experiments in the explosion chamber.

  9. Simulating fuel assemblies with low resolution CFD approaches

    Energy Technology Data Exchange (ETDEWEB)

    Roelofs, F., E-mail: roelofs@nrg.eu [NRG, Petten (Netherlands); Gopala, V.R. [NRG, Petten (Netherlands); Chandra, L. [IIT Rajasthan (India); Viellieber, M.; Class, A. [KIT, Karlsruhe (Germany)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer Justification for development of low resolution mesh approaches. Black-Right-Pointing-Pointer Mathematical background of the approaches. Black-Right-Pointing-Pointer Meshing considerations for different approaches are presented. Black-Right-Pointing-Pointer Examples of applications are provided. - Abstract: In addition to the traditional fuel assembly simulations using system codes, subchannel codes or porous medium approaches, as well as detailed CFD simulations to analyze single sub channels, a Low Resolution Geometry Resolving (LRGR) CFD approach and a Coarse-Grid-CFD (CGCFD) approach are taken. Both methods are based on a low resolution mesh that allows the capture of large and medium scale flow features such as recirculation zones, which are difficult to be reproduced by the system codes, subchannel codes and porous media approaches. The LRGR approach allows for instance fine-tuning the porous parameters which are important input for a porous medium approach. However, it should be noted that the prediction of detailed flow features such as secondary flows (small flows in the direction perpendicular to the main flow) is not feasible. Using this approach, the consequences of flow blockages for detection possibilities and cladding temperatures can be discussed. The goal of the CGCFD approach with SGM is that it can be applied to simulate complete fuel assemblies or even complete cores capturing the unique features of the complex flow induced by the fuel assembly geometry and its spacers. In such a case, grids with a very low grid resolution are employed. Within the CGCFD a subgrid model (SGM) accounts for sub grid volumetric forces which are derived from validated CFD simulations. The volumetric forces take account of the non resolved physics due to the coarse mesh. The current paper discusses and presents both, the CGCFD and the LRGR approaches.

  10. Intelligent Computational Systems. Opening Remarks: CFD Application Process Workshop

    Science.gov (United States)

    VanDalsem, William R.

    1994-01-01

    This discussion will include a short review of the challenges that must be overcome if computational physics technology is to have a larger impact on the design cycles of U.S. aerospace companies. Some of the potential solutions to these challenges may come from the information sciences fields. A few examples of potential computational physics/information sciences synergy will be presented, as motivation and inspiration for the Improving The CFD Applications Process Workshop.

  11. CFD Investigation into Diesel PCCI Combustion with Optimized Fuel Injection

    OpenAIRE

    Lipeng Lu; Bin Liu; Weiji Wang; Zhijun Peng

    2011-01-01

    A multi-pulse injection strategy for premixed charge compression ignition (PCCI) combustion was investigated in a four-valve, direct-injection diesel engine by a computational fluid dynamics (CFD) simulation using KIVA-3V code coupled with detailed chemistry. The effects of fuel splitting proportion, injection timing, spray angles, and injection velocity were examined. The mixing process and formation of soot and nitrogen oxide (NO x ) emissions were investigated as the focus of the research....

  12. Towards a rational theory for CFD global stability

    International Nuclear Information System (INIS)

    The fundamental notion of the consistent stability of semidiscrete analogues of evolution PDEs is explored. Lyapunov's direct method is used to develop CFD semidiscrete algorithms which yield the TVD constraint as a special case. A general formula for supplying dissipation parameters for arbitrary multidimensional conservation law systems is proposed. The reliability of the method is demonstrated by the results of two numerical tests for representative Euler shocked flows. 18 refs

  13. CFD as a Design Tool for a Concentric Heat Exchanger

    OpenAIRE

    Oosterhuis, J.P.; Bühler, S.; Wilcox, D.; Meer, Van Der

    2012-01-01

    A concentric gas-to-gas heat exchanger is designed for application as a recuperator in the domestic boiler industry. The recuperator recovers heat from the exhaust gases of a combustion process to preheat the ingoing gaseous fuel mixture resulting in increased fuel efficiency. This applied study shows the use of computational fluid dynamics (CFD) simulations as an efficient design tool for heat exchanger design. An experimental setup is developed and the simulation results are validated.

  14. CFD and FEM Model of an Underwater Vehicle Propeller

    OpenAIRE

    Chruściel Tadeusz; Ciba Ewelina; Dopke Julita

    2014-01-01

    Within the framework of the project for design and optimization of the Remotely Operated Vehicle (ROV), research on its propulsion has been carried out. Te entire project was supported by CFD and FEM calculations taking into account the characteristics of the underwater vehicle. One of the tasks was to optimize the semi-open duct for horizontal propellers, which provided propulsion and controllability in horizontal plane. In order to create a measurable model of this task it was necessary to ...

  15. Computational Fluid Dynamics (CFD) for Nuclear Reactor Safety Applications - Workshop Proceedings, CFD4NRS-3 - Experimental Validation and Application of CFD and CMFD Codes to Nuclear Reactor Safety Issues

    International Nuclear Information System (INIS)

    The purpose of the workshop was to provide a forum for numerical analysts and experimentalists to exchange information in the field of NRS-related activities relevant to CFD validation, with the objective of providing input to WGAMA CFD experts to create a practical, state-of-the-art, web-based assessment matrix on the use of CFD for NRS applications. The workshop included single-phase and multiphase CFD applications as well as new experimental techniques, including the following: Single-phase and two-phase CFD simulations with an emphasis on validation were sought in areas such as boiling flows, free-surface flows, direct contact condensation, and turbulent mixing. These should relate to NRS-relevant issues such as pressurized thermal shock, critical heat flux, pool heat exchangers, boron dilution, hydrogen distribution, and thermal striping. The use of systematic error quantification and Best Practice Guidelines (BPGs) was encouraged. Experiments providing data suitable for CFD validation-specifically in the area of NRS-including local measurement devices such as multi-sensor optical or electrical probes, Laser Doppler Velocimetry (LDV), hot-film/wire anemometry, Particle Image Velocimetry (PIV), Laser-Induced Fluorescence (LIF), and other innovative techniques. There were over 200 registered participants at the CFD4NRS-3 workshop. The program consisted of about 75 technical papers. Of these, 57 were oral presentations and 19 were posters. An additional 20 posters related to the OECD/NEA-sponsored CFD benchmark exercise on thermal fatigue in a T-Junction were presented. In addition, five keynote lectures were given by distinguished experts. This is about a 30 pc increase with respect to the previous XCFD4NRS workshop held in Grenoble in 2008, and a 70 pc increase compared to the first CFD4NRS workshop held in Garching in 2006. This confirms that there is a real and growing need for such workshops. The papers presented in the conference tackled different topics

  16. Visualization of CFD Results in Immersive Virtual Environments

    Science.gov (United States)

    Wasfy, Tamer M.; Noor Ahmed K.

    2001-01-01

    An object-oriented event-driven immersive virtual environment (VE) is described for the visualization of computational fluid dynamics (CFD) results. The VE incorporates the following types of primitive software objects: interface objects, support objects, geometric entities, and finite elements. The fluid domain is discretized using either a multi-block structured grid or an unstructured finite element mesh. The VE allows natural 'fly-through' visualization of the model, the CFD grid, and the model's surroundings. In order to help visualize the flow and its effects on the model, the VE incorporates the following objects: stream objects (lines, surface-restricted lines. ribbons. and volumes); colored surfaces; elevation surfaces; surface arrows; global and local iso-surfaces; vortex cores; and separation/attachment surfaces and lines. Most of these objects can be used for dynamically probing the flow. Particles and arrow animations can be displayed on top of stream objects. Primitive response quantities as well as derived quantities can be used. A recursive tree search algorithm is used for real-time point and value search in the CFD grid.

  17. CFD and FEM Model of an Underwater Vehicle Propeller

    Directory of Open Access Journals (Sweden)

    Chruściel Tadeusz

    2014-10-01

    Full Text Available Within the framework of the project for design and optimization of the Remotely Operated Vehicle (ROV, research on its propulsion has been carried out. Te entire project was supported by CFD and FEM calculations taking into account the characteristics of the underwater vehicle. One of the tasks was to optimize the semi-open duct for horizontal propellers, which provided propulsion and controllability in horizontal plane. In order to create a measurable model of this task it was necessary to analyze numerical methodology of propeller design, along with the structure of a propellers with nozzles and contra-rotating propellers. It was confronted with theoretical solutions which included running of the analyzed propeller near an underwater vehicle. Also preliminary qualitative analyses of a simplified system with contra-rotating propellers and a semi-open duct were carried out. Te obtained results enabled to make a decision about the ROVs duct form. Te rapid prototyping SLS (Selective Laser Sintering method was used to fabricate a physical model of the propeller. As a consequence of this, it was necessary to verify the FEM model of the propeller, which based on the load obtained from the CFD model. Te article contains characteristics of the examined ROV, a theoretical basis of propeller design for the analyzed cases, and the results of CFD and FEM simulations.

  18. A Scalable Infrastructure for Online Performance Analysis on CFD Application

    Institute of Scientific and Technical Information of China (English)

    HU Kai; DING Yi; ZHANG Xinyu; JIANG Shu

    2012-01-01

    The fast-growing demand of computational fluid dynamics (CFD) application for computing resources stimulates the development of high performance computing (HPC) and meanwhile raises new requirements for the technology of parallel application performance monitor and analysis.In response to large-scale and long-time running for the application of CFD,online and scalable performance analysis technology is required to optimize the parallel programs as well as to improve their operational efficiency.As a result,this research implements a scalable infrastructure for online performance analysis on CFD application with homogeneous or heterogeneous system.The infrastructure is part of the parallel application performance monitor and analysis system (PAPMAS) and is composed of two modules which are scalable data transmission module and data storage module.The paper analyzes and elaborates this infrastructure in detail with respect to its design and implementation.Furthermore,some experiments are carried out to verify the rationality and high efficiency of this infrastructure that could be adopted to meet the practical needs.

  19. A CFD model for pollutant dispersion in rivers

    Directory of Open Access Journals (Sweden)

    Modenesi K.

    2004-01-01

    Full Text Available Studies have shown that humankind will experience a water shortage in the coming decades. It is therefore paramount to develop new techniques and models with a view to minimizing the impact of pollution. It is important to predict the environmental impact of new emissions in rivers, especially during periods of drought. Computational fluid dynamics (CFD has proved to be an invaluable tool to develop models able to analyze in detail particle dispersion in rivers. However, since these models generate grids with thousands (even millions of points to evaluate velocities and concentrations, they still require powerful machines. In this context, this work contributes by presenting a new three-dimensional model based on CFD techniques specifically developed to be fast, providing a significant improvement in performance. It is able to generate predictions in a couple of hours for a one-thousand-meter long section of river using Pentium IV computers. Commercial CFD packages would require weeks to solve the same problem. Another innovation inb this work is that a half channel with a constant elliptical cross section represents the river, so the Navier Stokes equations were derived for the elliptical system. Experimental data were obtained from REPLAN (PETROBRAS refining unit on the Atibaia River in São Paulo, Brazil. The results show good agreement with experimental data.

  20. CFD simulation research on residential indoor air quality.

    Science.gov (United States)

    Yang, Li; Ye, Miao; He, Bao-Jie

    2014-02-15

    Nowadays people are excessively depending on air conditioning to create a comfortable indoor environment, but it could cause some health problems in a long run. In this paper, wind velocity field, temperature field and air age field in a bedroom with wall-hanging air conditioning running in summer are analyzed by CFD numerical simulation technology. The results show that wall-hanging air conditioning system can undertake indoor heat load and conduct good indoor thermal comfort. In terms of wind velocity, air speed in activity area where people sit and stand is moderate, most of which cannot feel wind flow and meet the summer indoor wind comfort requirement. However, for air quality, there are local areas without ventilation and toxic gases not discharged in time. Therefore it is necessary to take effective measures to improve air quality. Compared with the traditional measurement method, CFD software has many advantages in simulating indoor environment, so it is hopeful for humans to create a more comfortable, healthy living environment by CFD in the future. PMID:24365517

  1. CFD simulation of mixing for high-solids anaerobic digestion.

    Science.gov (United States)

    Wu, Binxin

    2012-08-01

    A computational fluid dynamics (CFD) model that simulates mechanical mixing for high-solids anaerobic digestion was developed. Numerical simulations of mixing manure slurry which exhibits non-Newtonian pseudo-plastic fluid behavior were performed for six designs: (i) one helical ribbon impeller; (ii) one anchor impeller; (iii) one curtain-type impeller; (iv) three counterflow (CF-2) impellers; (v) two modified high solidity (MHS 3/39°) impellers; and (vi) two pitched blade turbine impellers. The CFD model was validated against measurements for mixing a Herschel-Bulkley fluid by ribbon and anchor impellers. Based on mixing time with respect to mixing energy level, three impeller types (ribbon, CF-2, and MHS 3/39°) stand out when agitating highly viscous fluids, of these mixing with two MHS 3/39° impellers requires the lowest power input to homogenize the manure slurry. A comparison of digestion material demonstrates that the mixing energy varies with manure type and total solids concentration to obtain a given mixing time. Moreover, an in-depth discussion about the CFD strategy, the influences of flow regime and impeller type on mixing characteristics, and the intrinsic relation between mixing and flow field is included. PMID:22422446

  2. CFD simulation of air–steam flow with condensation

    Energy Technology Data Exchange (ETDEWEB)

    Vyskocil, Ladislav, E-mail: Ladislav.Vyskocil@ujv.cz; Schmid, Josef; Macek, Jiri

    2014-11-15

    Highlights: • Condensation model for CFD code Fluent. • Suitable for flow of air–steam mixture with additional non-condensable gases. • Suitable for both compressible and incompressible flow. • Successfully tested on the CONAN experiments and PANDA Test 9bis experiment. - Abstract: This article presents a custom condensation model for commercial CFD code Fluent. The condensation model was developed for the species transport model in Fluent code and it is suitable for both compressible and incompressible flow of air–steam mixture with additional non-condensable gases. The condensation model consists of two parts: condensation in volume and condensation on the wall. Condensation in volume is modeled by “return to saturation in constant time scale” method. Condensation on the wall is calculated from diffusion of steam through a layer of non-condensable gases near the wall. The performance of the condensation model was tested on the CONAN experiments. In these experiments, air–steam mixture flows downwards through a vertical channel with square cross section. One vertical wall of the channel is cooled and the steam condenses on it. The same model was then applied in simulation of PANDA Test 9bis experiment with condensation. In this test, two vessels connected with a pipe were filled with air; and steam was released into the first vessel. As the steam concentration increased in the vessels, the steam started condensing on the walls. The results of CFD simulations of both CONAN and PANDA experiments compared well with the measured data.

  3. CFD simulation on performance of new type umbrella plate scrubber

    Institute of Scientific and Technical Information of China (English)

    LI Shan-hong; LI Cai-ting; ZENG Guang-ming; LI Si-min; WANG Fei; WANG Da-yong

    2008-01-01

    A new type of umbrella plate scrubber was developed to address the pollution due to the dust, dioxide sulfur and other harmful gases, which were emitted from coal-burning boilers. The performance of the new device was studied through computational fluid dynamics(CFD) simulation and experiment methods. Initial work included experimental measurement of inlet-velocity, and gas phase simulation using Reynolds stress model(RSM). After gas phase was converged, particles were injected from the inlet of the new device. Discrete phase model(DPM) was used for particle trajectories determination. The pressure drop and the collection efficiency of the new device were predicted through simulation. The simulation results show that the pressure drop of the new devices is 230-250 Pa and the efficiency is 84%-86%, with the inlet velocity equal to 10.6 m/s and the dust concentration ranging from 2 to 22 g/m3. The CFD simulation results of the new device show good agreement with experimental data. The relative error of the pressure drop and the efficiency is approximately 4% and 10% respectively. The results obtained both from the numerical simulation and from the experiment demonstrate that CFD simulation is an effective method for this type of study.

  4. Fast-Track Design Efforts Using CFD: Bonneville Second Powerhouse

    Energy Technology Data Exchange (ETDEWEB)

    Rakowski, Cynthia L.; Ebner, Laurie L.; Richmond, Marshall C.

    2007-10-10

    A set of three-dimensional, computational fluid dynamics (CFD) models were developed and used for the Bonneville Project tailrace to study the impact of a proposed outfall structure on the tailrace hydraulics; these structures were designed to improve the survival of downstream migrant (juvenile) salmon. Flows were simulated by solving the Reynolds-Averaged Navier-Stokes equations together with a two-equation k-epsilon turbulences model in a commercial CFD code. The numerical model was validated using field-measured velocity data. The model results identified undesirable combinations of outfall location and operational scenarios and helped to identify the location in which the outfall structure was built. The numerical model provided a relatively low-cost tool to rapidly simulate and visualize the flow field for multiple proposed outfall locations for a large number of operational scenarios. The visualizations of the results from the CFD model provided insights to hydraulic engineers and fisheries biologists working on the design and placement of the outfall structure.

  5. Study of indoor radon distribution using measurements and CFD modeling.

    Science.gov (United States)

    Chauhan, Neetika; Chauhan, R P; Joshi, M; Agarwal, T K; Aggarwal, Praveen; Sahoo, B K

    2014-10-01

    Measurement and/or prediction of indoor radon ((222)Rn) concentration are important due to the impact of radon on indoor air quality and consequent inhalation hazard. In recent times, computational fluid dynamics (CFD) based modeling has become the cost effective replacement of experimental methods for the prediction and visualization of indoor pollutant distribution. The aim of this study is to implement CFD based modeling for studying indoor radon gas distribution. This study focuses on comparison of experimentally measured and CFD modeling predicted spatial distribution of radon concentration for a model test room. The key inputs for simulation viz. radon exhalation rate and ventilation rate were measured as a part of this study. Validation experiments were performed by measuring radon concentration at different locations of test room using active (continuous radon monitor) and passive (pin-hole dosimeters) techniques. Modeling predictions have been found to be reasonably matching with the measurement results. The validated model can be used to understand and study factors affecting indoor radon distribution for more realistic indoor environment.

  6. CFD DPAL modeling for various schemes of flow configurations

    Science.gov (United States)

    Waichman, Karol; Barmashenko, Boris D.; Rosenwaks, Salman

    2014-10-01

    Comprehensive analysis of kinetic and fluid dynamic processes in flowing-gas diode pumped alkali lasers (DPALs) using two- and three-dimensional computational fluid dynamics (2D and 3D CFD) models is reported for Cs DPALs. The models take into account effects of temperature rise and losses of alkali atoms due to ionization. Various gas flow regimes and transverse and parallel flow-optics directions configurations are studied. Optimization of the Cs DPAL parameters, using 3D CFD modeling, shows that applying high flow velocity and narrowband pumping, maximum lasing power as high as 40 kW can be obtained at pump power of 80 kW for transverse flow configuration in a pumped volume of ~ 0.7 cm3. At high pump power the calculated laser power is higher for the transverse scheme than for the parallel scheme because of a more efficient heat convection from the beam volume in the transverse configuration. The CFD models are applied to experimental devices and the calculated results are in good agreement with the measurements.

  7. CFD simulation of air–steam flow with condensation

    International Nuclear Information System (INIS)

    Highlights: • Condensation model for CFD code Fluent. • Suitable for flow of air–steam mixture with additional non-condensable gases. • Suitable for both compressible and incompressible flow. • Successfully tested on the CONAN experiments and PANDA Test 9bis experiment. - Abstract: This article presents a custom condensation model for commercial CFD code Fluent. The condensation model was developed for the species transport model in Fluent code and it is suitable for both compressible and incompressible flow of air–steam mixture with additional non-condensable gases. The condensation model consists of two parts: condensation in volume and condensation on the wall. Condensation in volume is modeled by “return to saturation in constant time scale” method. Condensation on the wall is calculated from diffusion of steam through a layer of non-condensable gases near the wall. The performance of the condensation model was tested on the CONAN experiments. In these experiments, air–steam mixture flows downwards through a vertical channel with square cross section. One vertical wall of the channel is cooled and the steam condenses on it. The same model was then applied in simulation of PANDA Test 9bis experiment with condensation. In this test, two vessels connected with a pipe were filled with air; and steam was released into the first vessel. As the steam concentration increased in the vessels, the steam started condensing on the walls. The results of CFD simulations of both CONAN and PANDA experiments compared well with the measured data

  8. Two Phase Flow Models and Numerical Methods of the Commercial CFD Codes

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Sung Won; Jeong, Jae Jun; Chang, Seok Kyu; Cho, Hyung Kyu

    2007-11-15

    The use of commercial CFD codes extend to various field of engineering. The thermal hydraulic analysis is one of the promising engineering field of application of the CFD codes. Up to now, the main application of the commercial CFD code is focused within the single phase, single composition fluid dynamics. Nuclear thermal hydraulics, however, deals with abrupt pressure changes, high heat fluxes, and phase change heat transfer. In order to overcome the CFD limitation and to extend the capability of the nuclear thermal hydraulics analysis, the research efforts are made to collaborate the CFD and nuclear thermal hydraulics. To achieve the final goal, the current useful model and correlations used in commercial CFD codes should be reviewed and investigated. This report gives the summary information about the constitutive relationships that are used in the FLUENT, STAR-CD, and CFX. The brief information of the solution technologies are also enveloped.

  9. Two Phase Flow Models and Numerical Methods of the Commercial CFD Codes

    International Nuclear Information System (INIS)

    The use of commercial CFD codes extend to various field of engineering. The thermal hydraulic analysis is one of the promising engineering field of application of the CFD codes. Up to now, the main application of the commercial CFD code is focused within the single phase, single composition fluid dynamics. Nuclear thermal hydraulics, however, deals with abrupt pressure changes, high heat fluxes, and phase change heat transfer. In order to overcome the CFD limitation and to extend the capability of the nuclear thermal hydraulics analysis, the research efforts are made to collaborate the CFD and nuclear thermal hydraulics. To achieve the final goal, the current useful model and correlations used in commercial CFD codes should be reviewed and investigated. This report gives the summary information about the constitutive relationships that are used in the FLUENT, STAR-CD, and CFX. The brief information of the solution technologies are also enveloped

  10. CFD analysis on heat transfer in low Prandtl number fluid flows

    International Nuclear Information System (INIS)

    Use of Computational Fluid Dynamics (CFD) code is helpful for designing liquid metal cooled nuclear reactor systems. Before using any CFD code proper evaluation of the code is essential for simulation of heat transfer in liquid metal flow. In this paper, a review of the literature on the correlations for liquid metal heat transfer is carried out and a comparison with experimental results is performed. CFD analysis is carried out using PHOENICS-3.6 code on heat transfer in molten Lead Bismuth Eutectic (LBE) flowing through tube. Turbulent flow analyses are carried out for the evaluation of the CFD code. The CFD results are compared with the available correlations. Assessment of various turbulence models and correlations for turbulent Prandtl number in the tube geometry are carried out. From the analysis it is found that, the CFD prediction can be improved with modified turbulent Prandtl number in the turbulence models. (author)

  11. Validation of CFD Simulations of Cerebral Aneurysms With Implication of Geometric Variations

    OpenAIRE

    Hoi, Yiemeng; Woodward, Scott H.; Kim, Minsuok; Taulbee, Dale B.; Meng, Hui

    2006-01-01

    Computational fluid dynamics (CFD) simulations using medical-image-based anatomical vascular geometry are now gaining clinical relevance. This study aimed at validating the CFD methodology for studying cerebral aneurysms by using particle image velocimetry (PIV) measurements, with a focus on the effects of small geometric variations in aneurysm models on the flow dynamics obtained with CFD. Method of Approach. An experimental phantom was fabricated out of silicone elastomer to best mimic a sp...

  12. Investigation on Improved Correlation of CFD and EFD for Supercritical Airfoil

    OpenAIRE

    Xin Xu; Da-wei Liu; De-hua Chen; Zhi Wei; Yuan-jing Wang

    2014-01-01

    It is necessary to improve the correlation between CFD and EFD through the correction of EFD results and validation of CFD method, thus investigating the aerodynamic characteristics of supercritical airfoil perfectly. In this study, NASA SC (2) -0714 airfoil is numerically simulated and compared with NASA corrected experimental results to validate the CFD method. The Barnwell-Sewell method is applied to correct sidewall effects for experimental results of typical supercritical airfoil CH obta...

  13. CFD Analysis of the Effect on Buoyancy Due to Terrain Temperature Based on an Integrated DEM and Landsat Infrared Imagery Análisis CFD de vientos convectivos naturales debidos a la temperatura de un terreno basado en un modelo DEM integrado con imágenes infrarrojas Landsat

    Directory of Open Access Journals (Sweden)

    Santiago Giraldo

    2008-12-01

    aire sobre la superficie del terreno (Dominio CFD. Datos obtenidos de la misión satelital Landsat fueron utilizados para establecer temperaturas sobre el terreno para distintos materiales y fue mapeada sobre el terreno utilizando técnicas de interpolación. Las ecuaciones de Navier–Stokes fueron solucionadas para modelos de fenómenos de convección natural con efectos de flujo turbulento de fluidos compresibles, tomando en cuenta efectos convectivos y de transferencia de calor. La simulación incluye convección y condiciones de turbulencia bajo el modelo k–epsilon utilizando las instalaciones de computaci´on de alto desempeño de Westgrid (Western Canada Research Grid. Los resultados preliminares muestran distribuciones de viento comparables a las observadas en la región de baja altitud

  14. Computational Fluid Dynamics (CFD) applications in rocket propulsion analysis and design

    Science.gov (United States)

    McConnaughey, P. K.; Garcia, R.; Griffin, L. W.; Ruf, J. H.

    1993-11-01

    Computational Fluid Dynamics (CFD) has been used in recent applications to affect subcomponent designs in liquid propulsion rocket engines. This paper elucidates three such applications for turbine stage, pump stage, and combustor chamber geometries. Details of these applications include the development of a high turning airfoil for a gas generator (GG) powered, liquid oxygen (LOX) turbopump, single-stage turbine using CFD as an integral part of the design process. CFD application to pump stage design has emphasized analysis of inducers, impellers, and diffuser/volute sections. Improvements in pump stage impeller discharge flow uniformity have been seen through CFD optimization on coarse grid models. In the area of combustor design, recent CFD analysis of a film cooled ablating combustion chamber has been used to quantify the interaction between film cooling rate, chamber wall contraction angle, and geometry and their effects of these quantities on local wall temperature. The results are currently guiding combustion chamber design and coolant flow rate for an upcoming subcomponent test. Critical aspects of successful integration of CFD into the design cycle includes a close-coupling of CFD and design organizations, quick turnaround of parametric analyses once a baseline CFD benchmark has been established, and the use of CFD methodology and approaches that address pertinent design issues. In this latter area, some problem details can be simplified while retaining key physical aspects to maintain analytical integrity.

  15. Non-Newtonian Liquid Flow through Small Diameter Piping Components: CFD Analysis

    Science.gov (United States)

    Bandyopadhyay, Tarun Kanti; Das, Sudip Kumar

    2016-05-01

    Computational Fluid Dynamics (CFD) analysis have been carried out to evaluate the frictional pressure drop across the horizontal pipeline and different piping components, like elbows, orifices, gate and globe valves for non-Newtonian liquid through 0.0127 m pipe line. The mesh generation is done using GAMBIT 6.3 and FLUENT 6.3 is used for CFD analysis. The CFD results are verified with our earlier published experimental data. The CFD results show the very good agreement with the experimental values.

  16. Flow induced vibration forces on a fuel rod by LES CFD analysis

    International Nuclear Information System (INIS)

    The purpose of the present study is to evaluate the feasibility of use of CFD Large Eddy Simulation (LES) modeling techniques in CD-adapco CFD code STAR-CCM+ to calculate the instantaneous stress tensor on the fuel rod wall and then utilize these data for mechanical calculations. Transient hydraulic forces on the fuel rod resulting from the CFD model are linked to the Westinghouse VITRAN code to predict fuel rod vibration response. The coupled CFD/mechanical solution has provided a reasonable prediction of fuel rod vibration and a more accurate representation of all the important physics and excitation forces. (author)

  17. Validation of NEPTUNE-CFD two-phase flow models using experimental data

    OpenAIRE

    Jorge Pérez Mañes; Victor Hugo Sánchez Espinoza; Sergio Chiva Vicent; Michael Böttcher; Robert Stieglitz

    2014-01-01

    This paper deals with the validation of the two-phase flow models of the CFD code NEPTUNEC-CFD using experimental data provided by the OECD BWR BFBT and PSBT Benchmark. Since the two-phase models of CFD codes are extensively being improved, the validation is a key step for the acceptability of such codes. The validation work is performed in the frame of the European NURISP Project and it was focused on the steady state and transient void fraction tests. The influence of different NEPTUNE-CFD ...

  18. EFECTO DEL CARBONATO DE POTASIO EN LA EVOLUCIÓN DE LOS GRUPOS FUNCIONALES DE LOS BIOCRUDOS DE CONVERSIÓN HIDROTÉRMICA DE BIOMASA LIGNOCELULÓSICA ALREDEDOR DEL PUNTO CRÍTICO DEL AGUA

    Directory of Open Access Journals (Sweden)

    José Díaz

    2009-04-01

    Full Text Available Un tipo de biomasa pobre en lignina, del género Pennisetum fue sometida al proceso de conversión hidrotérmica en presencia de carbonato de potasio como catalizador. Las reacciones se llevaron a cabo en ambientes cercanos al punto crítico del agua. Los productos de reacción no acuosos (biocrudo se separaron por decantación y se analizaron por espectrometría infrarroja. Los biocrudos obtenidos contienen compuestos con funcionalidades aromáticas, olefínicas, hidroxiladas, éteres, y para el caso del biocrudo obtenido bajo la condición subcrítica funciones carbonilo. La fracción gaseosa y el biocrudo aumentan en presencia del carbonato de potasio.   

  19. Biomasa de la vegetación herbacea y leñosa pequeña y necromasa en el área de influencia de la central hidroeléctrica Porce II

    OpenAIRE

    Herrera Arango, María Alejandra

    2002-01-01

    Este trabajo se realizó en los bosques primarios y secundarios del área de influencia de la Central Hidroeléctrica Porce II, en el departamento de Antioquia, Colombia. La región se encuentra entre 925 y 1500 msnm, con una precipitación promedia anual de 3050 mm/año. Se cuantificó el aporte de la vegetación herbácea y leñosa pequeña (VH&LP) como parte de la biomasa aérea, así como el aporte de los detritos vegetales tanto en el suelo como el vuelo (hojarasca fina, detritos de madera gruesa y á...

  20. Determinación de carbono orgánico total presente en el suelo y la biomasa de los páramos de las comunidades de chimborazo y shobol llinllin en Ecuador

    Directory of Open Access Journals (Sweden)

    M. Echeverría

    2013-01-01

    Full Text Available En la determinación del contenido de carbono orgánico total presente en el suelo y la biomasa (cobertura vegetal de los páramos de las comunidades de Chimborazo, con 210ha de páramo cuya ubicación es 746667UTM-9825400UTM, y Shobol Llinllín, con 350 ha de páramo, 754680UTM–9854678UTM, pertenecientes a San Juan en Ecuador, se seleccionaron 9 puntos de muestreo de acuerdo a la variación, características y altitud del suelo, repartidos para este estudio en tres pisos altitudinales comprendidos, para el páramo de la comunidad Chimborazo, entre 3600-3900 msnm y, en el caso de Shobol Llinllín, entre 3600-3950 msnm.

  1. Reducing uncertainty and bias in acoustic biomass estimations of southern blue whiting (Micromesistius australis in the southeastern Pacific: transducer motion effects upon acoustic attenuation Reduciendo el sesgo e incertidumbre de las estimaciones hidroacústicas de biomasa de merluza de tres aletas (Micromesistius australis en el Pacífico suroriental: efectos del movimiento del transductor sobre la atenuación acústica

    Directory of Open Access Journals (Sweden)

    Alvaro Saavedra

    2012-09-01

    Full Text Available We evaluated the loss of sensitivity due to the motion experienced by a hull-mounted transducer and its effects upon the estimated biomass of southern blue whiting (Micromesistius australis in an acoustic survey conducted in the southeastern Pacific, off the Chilean coast, during the austral winter of 2009. Vessel motion data (pitch and roll were registered in situ using a digital clinometer and used to correct the nautical area scattering coefficients (NASC in elementary sampling units of 926 m distance by 10 m depth. These NASC correction factors (NASCcp were calculated using Dunford's algorithm for circular transducers. We found high variability in NASCcp, which averaged 12%, and ranged between 0 and 50%. NASCcp variability was explained significantly by the mean depth of the integrated stratum (33%, the weather condition, as measured by Beaufort's scale (5%, and the vessel course relative to wind direction (2%. The empirical model we used to explain NASC Cp variability may be suitable for correcting bias due to transducer motion in other, past and future, fisheries acoustic surveys targeting mid-water species under rough weather conditions.Se evaluó la pérdida de sensibilidad producida por el movimiento de un transductor montado en el casco y sus efectos sobre la abundancia y biomasa estimada de merluza de tres aletas (Micromesistius australis en un estudio acústico realizado en el Pacífico suroriental, frente a la costa de Chile, durante el invierno austral de 2009. Los datos de movimiento del barco (cabeceo y balanceo fueron registrados in situ utilizando un clinómetro digital y luego utilizados para estimar la pérdida teórica de sensibilidad del transductor y, finalmente, traducir esta pérdida en factores de corrección del coeficiente de dispersión por área náutica (NASC calculados para intervalos básicos de muestreo de 926 m de distancia por 10 m de profundidad. Los factores de corrección del NASC (NASC Cp fueron calculados

  2. CFD simulation of air discharge tests in the PPOOLEX facility

    Energy Technology Data Exchange (ETDEWEB)

    Tanskanen, V.; Puustinen, M. (Lappeenranta Univ. of Technology, Nuclear Safety Research Unit (Finland))

    2008-07-15

    This report summarizes the CFD simulation results of two air discharge tests of the characterizing test program in 2007 with the scaled down PPOOLEX facility. Air was blown to the dry well compartment and from there through a DN200 blowdown pipe into the condensation pool (wet well). The selected tests were modeled with Fluent CFD code. Test CHAR-09-1 was simulated to 28.92 seconds of real time and test CHAR-09-3 to 17.01 seconds. The VOF model was used as a multiphase model and the standard k epsilon-model as a turbulence model. Occasional convergence problems, usually at the beginning of bubble formation, required the use of relatively short time stepping. The simulation time costs threatened to become unbearable since weeks or months of wall-clock time with 1-2 processors were needed. Therefore, the simulated time periods were limited from the real duration of the experiments. The results obtained from the CFD simulations are in a relatively good agreement with the experimental results. Simulated pressures correspond well to the measured ones and, in addition, fluctuations due to bubble formations and breakups are also captured. Most of the differences in temperature values and in their behavior seem to depend on the locations of the measurements. In the vicinity of regions occupied by water in the experiments, thermocouples getting wet and drying slowly may have had an effect on the measured temperature values. Generally speaking, most temperatures were simulated satisfyingly and the largest discrepancies could be explained by wetted thermocouples. However, differences in the dry well and blowdown pipe top measurements could not be explained by thermocouples getting wet. Heat losses and dry well / wet well heat transfer due to conduction have neither been estimated in the experiments nor modeled in the simulations. Estimation of heat conduction and heat losses should be carried out in future experiments and they should be modeled in future simulations, too. (au)

  3. CFD evaluation of SFP cooling capacity during normal operating conditions

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Dong Hyeog; Kim, Jin Hyuck; Seul, Kwang Won [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2012-10-15

    In Fukushima nuclear accident, due to earthquake, the cooling system of the spent fuel pool failed and the safety issue of the spent fuel pool (SFP) generated. Because of the unavailability of offsite storage for spent nuclear fuel in Korea, the spent fuel should be placed in storage at specially designed facilities, kept and monitored in the plant. In recent years, spent fuel storage racks are being replaced with high density racks due to the lack of storage capacity. For the above reasons, the necessity is felt to analyze the safety of the spent fuel pool. Hence, to evaluate the safety of spent fuel pools, in case of loss of offsite power like the Fukushima nuclear accident, the safety analysis was conducted for Gori Unit 1 and Ulchin unit3 in order to estimate the time it takes for nuclear fuels to be uncovered, when water in the pool evaporated by decay heat of spent fuels. In addition, there are some researches evaluating heat removal, thermal hydraulic behaviors and accident circumstances in the spent fuel pool with system thermal hydraulic codes, such as RELAP, TRACE and ASTEC. Some researchers are attempting to carry out 3D CFD analysis. In this study, thermal hydraulic characteristics of the spent fuel pool of Ulchin unit 3 are investigated by using ANSYS CFX 13 which is a commercial CFD code. Three dimensional fluid flow and heat removal capacity of the spent fuel pool are evaluated by 3 D CFD simulation, while carrying out comparative analysis with the multi D analysis of MARS KS.

  4. Coupling CFD code with system code and neutron kinetic code

    International Nuclear Information System (INIS)

    Highlights: • Coupling interface between CFD code Fluent and system code Athlet was created. • Athlet code is internally coupled with neutron kinetic code Dyn3D. • Explicit coupling of overlapped computational domains was used. • A coupled system of Athlet/Dyn3D+Fluent codes was successfully tested on a real case. - Abstract: The aim of this work was to develop the coupling interface between CFD code Fluent and system code Athlet internally coupled with neutron kinetic code Dyn3D. The coupling interface is intended for simulation of complex transients such as Main Steam Line Break scenarios, which cannot be modeled separately first by system and neutron kinetic code and then by CFD code, because of the feedback between the codes. In the first part of this article, the coupling method is described. Explicit coupling of overlapped computational domains is used in this work. The second part of the article presents a demonstration simulation performed by the coupled system of Athlet/Dyn3D and Fluent. The “Opening a Steam Dump to the Atmosphere” test carried out at the Temelin NPP (VVER-1000) was simulated by the coupled system. In this simulation, the primary and secondary circuits were modeled by Athlet, mixing in downcomer and lower plenum was simulated by Fluent and heat generation in the core was calculated by Dyn3D. The results of the simulation with Athlet/Dyn3D+Fluent were compared with the experimental data and the results from a calculation performed with Athlet/Dyn3D without Fluent

  5. EXAMPLE APPLICATION OF CFD SIMULATIONS FOR SHORT-RANGE ATMOSPHERIC DISPERSION OVER THE OPEN FIELDS OF PROJECT PRAIRIE GRASS

    Science.gov (United States)

    Computational Fluid Dynamics (CFD) techniques are increasingly being applied to air quality modeling of short-range dispersion, especially the flow and dispersion around buildings and other geometrically complex structures. The proper application and accuracy of such CFD techniqu...

  6. CFD simulations of heat transfer in internally helically ribbed tubes

    Directory of Open Access Journals (Sweden)

    Majewski Karol

    2016-06-01

    Full Text Available Heating surfaces in power boilers are exposed to very high heat flux. For evaporator protection against overheating, internally helically ribbed tubes are used. The intensification of the heat transfer and the maintenance of the thin water layer in the intercostal space, using ribbed tubes, enables better protection of the power boiler evaporator than smooth pipes. Extended inner surface changes flow and thermal conditions by influencing the linear pressure drop and heat transfer coefficient. This paper presents equations that are used to determine the heat transfer coefficient. The results of total heat transfer, obtained from CFD simulations, for two types of internally ribbed and plain tubes are also presented.

  7. CFD Studies on Multi Lead Rifled [MLR] Boiler Tubes

    Directory of Open Access Journals (Sweden)

    Dr T C Mohankumar

    2013-09-01

    Full Text Available This paper reports the merits of multi lead rifled [MLR] tubes in vertical water tube boiler using CFD tool. Heat transfer enhancement of MLR tubes was mainly taken in to consideration. Performance of multi lead rifled tube was studied by varying its influencing geometrical parameter like number of rifling, height of rifling, length of pitch of rifling for a particular length. The heat transfer analysis was done at operating conditions of an actual coal fired water tube boiler situated at Apollo Tyres LTD, Chalakudy, India for saturated process steam production. The results showed that the heat transfer increased when compared with existing inner plane wall water tubes.

  8. Aerodynamic investigation of winglets on wind turbine blades using CFD

    DEFF Research Database (Denmark)

    Johansen, Jeppe; Sørensen, Niels N.

    2006-01-01

    The present report describes the numerical investigation of the aerodynamics around a wind turbine blade with a winglet using Computational Fluid Dynamics, CFD. Five winglets were investigated with different twist distribution and camber. Four of them were pointing towards the pressure side...... (upstream) and one was pointing towards the suction side (downstream). Additionally, a rectangular modification of the original blade tip was designed with the same planform area as the blades with winglets. Results show that adding a winglet to the existing blade increase the force distribution...

  9. CFD Analysis of a Pelton Turbine in OpenFOAM

    OpenAIRE

    Rygg, Jone Rivrud

    2013-01-01

    During the spring of 2012, Lorentz Fjellanger Barstad developed a method for modelling the flow in a Pelton turbine subject to a high-speed water jet using the Computational Fluid Dynamics (CFD) software ANSYS CFX. The torque measurement was validated against experimental data. The aim of this master's thesis has been to develop a similar method with the Open Source tool OpenFOAM and to compare the two models.A method has been created using the OpenFOAM solver interDyMFoam, capable of ha...

  10. Parallel computers and parallel algorithms for CFD: An introduction

    Science.gov (United States)

    Roose, Dirk; Vandriessche, Rafael

    1995-10-01

    This text presents a tutorial on those aspects of parallel computing that are important for the development of efficient parallel algorithms and software for computational fluid dynamics. We first review the main architectural features of parallel computers and we briefly describe some parallel systems on the market today. We introduce some important concepts concerning the development and the performance evaluation of parallel algorithms. We discuss how work load imbalance and communication costs on distributed memory parallel computers can be minimized. We present performance results for some CFD test cases. We focus on applications using structured and block structured grids, but the concepts and techniques are also valid for unstructured grids.

  11. Openfoam: možnosti open-source CFD

    OpenAIRE

    Zbavitel, Jan

    2016-01-01

    Bakalářská práce je zaměřena na základní analýzu možností open-source CFD programu OpenFoam a představení jeho klíčových vlastností. Získané vědomosti budou využity při tutoriální úloze analýzy Kármánovy vírové stezky.

  12. CFD study of thick flatback airfoils using OpenFOAM

    OpenAIRE

    Milián Sanz, José María

    2010-01-01

    New airfoil designs are created in order to improve both the structural and aerodynamic properties of a wind turbine blade, one example of these are flatback airfoils. Furthermore, a new CFD programme exists in order to study the behavior of the flow around an airfoil, OpenFOAM. The flow around these new airfoils using OpenFOAM is studied in the present thesis. It is used the turbulence model k-! SST for fully turbulent boundary layer and free transition at the boundary layer, modeled with th...

  13. Modeling chemical reactions in the indoor environment by CFD

    DEFF Research Database (Denmark)

    Sørensen, Dan Nørtoft; Weschler, Charles J.

    2002-01-01

    The concentrations of ozone and a terpene that react in the gas-phase to produce a hypothetical product were investigated by computational fluid dynamics (CFD) for two different air exchange rates. Ozone entered the room with the ventilation air. The terpenes were introduced as a localized source...... with an emission pattern similar to an air freshener; this was in contrast to an otherwise identical earlier study in which the terpene was introduced as a floor source with an emission pattern similar to a floor care product (Sørensen and Weschler, 2002). The results show that there are large concentration...

  14. Standard Problems for CFD Validation for NGNP - Status Report

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) is conducting research and development to support the resurgence of nuclear power in the United States for both electrical power generation and production of process heat required for industrial processes such as the manufacture of hydrogen for use as a fuel in automobiles. The project is called the Next Generation Nuclear Plant (NGNP) Project, which is based on a Generation IV reactor concept called the very high temperature reactor (VHTR). The VHTR will be of the prismatic or pebble bed type; the former is considered herein. The VHTR will use helium as the coolant at temperatures ranging from 250 C to perhaps 1000 C. While computational fluid dynamics (CFD) has not previously been used for the safety analysis of nuclear reactors in the United States, it is being considered for existing and future reactors. It is fully recognized that CFD simulation codes will have to be validated for flow physics reasonably close to actual fluid dynamic conditions expected in normal operational and accident situations. The ''Standard Problem'' is an experimental data set that represents an important physical phenomenon or phenomena, whose selection is based on a phenomena identification and ranking table (PIRT) for the reactor in question. It will be necessary to build a database that contains a number of standard problems for use to validate CFD and systems analysis codes for the many physical problems that will need to be analyzed. The first two standard problems that have been developed for CFD validation consider flow in the lower plenum of the VHTR and bypass flow in the prismatic core. Both involve scaled models built from quartz and designed to be installed in the INL's matched index of refraction (MIR) test facility. The MIR facility employs mineral oil as the working fluid at a constant temperature. At this temperature, the index of refraction of the mineral oil is the same as that of the quartz. This provides an advantage to the

  15. CFD APPROACH FOR FLOW CHARACTERISTICS OF HYDRAULIC FRANCIS TURBINE

    Directory of Open Access Journals (Sweden)

    RUCHI KHARE,

    2010-08-01

    Full Text Available With the growth of computational mechanics, the virtual hydraulic machines are becoming more and more realistic to get minor details of the flow, which are not possible in model testing. In present work, 3D turbulent real flow analyses in hydraulic Francis turbine have been carried out at three guide vane opening and different rotation speed using Ansys CFX computational fluid dynamics (CFD software. The average values of flow parameters like velocities and flow angles at the inlet and outlet of runner, guide vane and stay vane of turbine are computed to derive flow characteristics.

  16. Transient CFD simulation of a Francis turbine startup

    Science.gov (United States)

    Nicolle, J.; Morissette, J. F.; Giroux, A. M.

    2012-11-01

    To assess the life expectancy of hydraulic turbines, it is essential to obtain the loading on the blades, especially during transient operations known to be the most damaging. This paper presents a simplified CFD setup to model the startup phase of a Francis turbine while it goes from rest to speed no-load condition. The fluid domain included one distributor sector coupled with one runner passage. The guide vane motion and change in the angular velocity were included in a commercial code with user functions. Comparisons between numerical results and measurements acquired on a full-size turbine showed that most of the flow physics occurring during startup were captured.

  17. Development of hydraulic tanks by multi-phase CFD simulation

    OpenAIRE

    Vollmer, Thees; Frerichs, Ludger

    2016-01-01

    Hydraulic tanks have a variety of different tasks. The have to store the volume of oil needed for asymmetric actors in the system as well as to supply the system with preconditioned oil. This includes the deaeration as air contamination is affecting the overall system performance. The separation of the air in the tank is being realized mainly by passive methods, improving the guidance of the air and oil flow. The use of CFD models to improve the design of hydraulic tank is recently often disc...

  18. CFD Simulations Of Sonic Booms In Near And Mid Fields

    Science.gov (United States)

    Cheung, Samson H.; Edwards, Thomas A.; Lawrence, Scott L.

    1992-01-01

    Report discusses computational fluid dynamics (CFD) to simulate generation and propagation of sonic booms in near- and mid-field regions of supersonic flows about simplified bodies representative of advanced airplanes. Parabolized Navier-Stokes equations integrated by implicit, approximate-factorization, finite-volume algorithm in which crossflow inviscid fluxes evaluated by Roe's flux-difference-splitting scheme. Near-field solutions obtained by applying algorithm to flows immediately surrounding bodies. Solutions transferred to computer codes based on Whitham"s F-function theory for extrapolation to far-field.

  19. CFD simulation of an offshore air intake and exhaust system

    OpenAIRE

    Sirevaag, Ola

    2015-01-01

    The main purpose is to investigate whether the exhaust gases from an offshore turbine can be rerouted to heat the air entering the turbine system, thus keeping air humidity concentration above acceptable levels. To ensure this, temperature of the incoming airflow must be above 4,5 degrees Celsius. Currently the exhaust is vented out to the atmosphere and an electrical anti-icing system is used to heat the air intake. The objective of this thesis is therefore to make a CFD model in OpenFOAM to...

  20. CFD modeling of dust dispersion through Najaf historic city centre

    Directory of Open Access Journals (Sweden)

    Maher A.R. Sadiq Al-Baghdadi

    2014-01-01

    Full Text Available The aim of this project is to study the influences of the wind flow and dust particles dispersion through Najaf historic city centre. Two phase Computational Fluid Dynamics (CFD model using a Reynolds Average Navier Stokes (RANS equations has been used to simulate the wind flow and the transport and dispersion of the dust particles through the historic city centre. This work may provide useful insight to urban designers and planners interested in examining the variation of city breathability as a local dynamic morphological parameter with the local building packing density.

  1. Scaling studies and conceptual experiment designs for NGNP CFD assessment

    Energy Technology Data Exchange (ETDEWEB)

    D. M. McEligot; G. E. McCreery

    2004-11-01

    The objective of this report is to document scaling studies and conceptual designs for flow and heat transfer experiments intended to assess CFD codes and their turbulence models proposed for application to prismatic NGNP concepts. The general approach of the project is to develop new benchmark experiments for assessment in parallel with CFD and coupled CFD/systems code calculations for the same geometry. Two aspects of the complex flow in an NGNP are being addressed: (1) flow and thermal mixing in the lower plenum ("hot streaking" issue) and (2) turbulence and resulting temperature distributions in reactor cooling channels ("hot channel" issue). Current prismatic NGNP concepts are being examined to identify their proposed flow conditions and geometries over the range from normal operation to decay heat removal in a pressurized cooldown. Approximate analyses have been applied to determine key non-dimensional parameters and their magnitudes over this operating range. For normal operation, the flow in the coolant channels can be considered to be dominant turbulent forced convection with slight transverse property variation. In a pressurized cooldown (LOFA) simulation, the flow quickly becomes laminar with some possible buoyancy influences. The flow in the lower plenum can locally be considered to be a situation of multiple hot jets into a confined crossflow -- with obstructions. Flow is expected to be turbulent with momentumdominated turbulent jets entering; buoyancy influences are estimated to be negligible in normal full power operation. Experiments are needed for the combined features of the lower plenum flows. Missing from the typical jet experiments available are interactions with nearby circular posts and with vertical posts in the vicinity of vertical walls - with near stagnant surroundings at one extreme and significant crossflow at the other. Two types of heat transfer experiments are being considered. One addresses the "hot channel" problem, if necessary

  2. Application of CFD based wave loads in aeroelastic calculations

    DEFF Research Database (Denmark)

    Schløer, Signe; Paulsen, Bo Terp; Bredmose, Henrik

    2014-01-01

    realizations compare well with corresponding surface elevations from laboratory experiments. In aeroelastic calculations of an offshore wind turbine on a monopile foundation the hydrodynamic loads due to the potential flow solver and Morison’s equation and the hydrodynamic loads calculated by the coupled......Two fully nonlinear irregular wave realizations with different significant wave heights are considered. The wave realizations are both calculated in the potential flow solver Ocean-Wave3D and in a coupled domain decomposed potential-flow CFD solver. The surface elevations of the calculated wave...

  3. Cfd Studies of Two Stroke Petrol Engine Scavenging

    OpenAIRE

    S Gavudhama Karunanidhi,; NithinV S

    2014-01-01

    This project deals with the numerical analysis of 2 stroke engine scavenging in two cases. One with an existing condition (Flat headed pistons) and another with a new design (Dome headed piston) .The numerical analysis is done with help of CFD software ANSYS FLUENT 14.5. Here, the modeling of engine piston with flat headed type and with dome headed types was done in workbench. In ANSYS FLUENT after the geometrical design, for the dynamic motion meshing is used and set up speci...

  4. CFD Analysis of the 24-inch JIRAD Hybrid Rocket Motor

    Science.gov (United States)

    Liang, Pak-Yan; Ungewitter, Ronald; Claflin, Scott

    1996-01-01

    A series of multispecies, multiphase computational fluid dynamics (CFD) analyses of the 24-inch diameter joint government industry industrial research and development (JIRAD) hybrid rocket motor is described. The 24-inch JIRAD hybrid motor operates by injection of liquid oxygen (LOX) into a vaporization plenum chamber upstream of ports in the hydroxyl-terminated polybutadiene (HTPB) solid fuel. The injector spray pattern had a strong influence on combustion stability of the JIRAD motor so a CFD study was initiated to define the injector end flow field under different oxidizer spray patterns and operating conditions. By using CFD to gain a clear picture of the flow field and temperature distribution within the JIRAD motor, it is hoped that the fundamental mechanisms of hybrid combustion instability may be identified and then suppressed by simple alterations to the oxidizer injection parameters such as injection angle and velocity. The simulations in this study were carried out using the General Algorithm for Analysis of Combustion SYstems (GALACSY) multiphase combustion codes. GALACSY consists of a comprehensive set of droplet dynamic submodels (atomization, evaporation, etc.) and a computationally efficient hydrocarbon chemistry package built around a robust Navier-Stokes solver optimized for low Mach number flows. Lagrangian tracking of dispersed particles describes a closely coupled spray phase. The CFD cases described in this paper represent various levels of simplification of the problem. They include: (A) gaseous oxygen with combusting fuel vapor blowing off the walls at various oxidizer injection angles and velocities, (B) gaseous oxygen with combusting fuel vapor blowing off the walls, and (C) liquid oxygen with combusting fuel vapor blowing off the walls. The study used an axisymmetric model and the results indicate that the injector design significantly effects the flow field in the injector end of the motor. Markedly different recirculation patterns are

  5. 650V CoolMOS CFD2:MOSFET

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    英飞凌推出了650V CoolMOS CFD2,它是漏源击穿电压为650V并且集成了快速体二极管的高压晶体管。器件延续了600VCFD产品的特点,不仅可以提高能效,而且具备更软的交换功能,从而降低了电磁干扰(EMI)。

  6. Variabilidad del ritmo de nado utilizando un sistema de información sonoro

    OpenAIRE

    Javaloyes Torres, Alejandro

    2014-01-01

    El ritmo de nado en natación es un parámetro muy importante a utilizar en el control de entrenamiento y para tener un mejor rendimiento en competición. La propuesta de nuestro estudio es comparar el ritmo de nado comparando 3 situaciones, sin información, con información visual y sonora o utilizando un dispositivo de transmisión de información audio.

  7. An overview of CFD and PIV application in investigation of solar thermal systems

    DEFF Research Database (Denmark)

    Ai, Ning; Fan, Jianhua; Ji, Jianbing

    2007-01-01

    . The most promising solution to this challenge is the use of computational fluid dynamics (CFD) in combination with particle image velocimetry (PIV),which will be the future trend in the investigation of solar thermal systems. The aim of this work is to give an overview of the status of the CFD...

  8. Sources of error in CEMRA-based CFD simulations of the common carotid artery

    Science.gov (United States)

    Khan, Muhammad Owais; Wasserman, Bruce A.; Steinman, David A.

    2013-03-01

    Magnetic resonance imaging is often used as a source for reconstructing vascular anatomy for the purpose of computational fluid dynamics (CFD) analysis. We recently observed large discrepancies in such "image-based" CFD models of the normal common carotid artery (CCA) derived from contrast enhanced MR angiography (CEMRA), when compared to phase contrast MR imaging (PCMRI) of the same subjects. A novel quantitative comparison of velocity profile shape of N=20 cases revealed an average 25% overestimation of velocities by CFD, attributed to a corresponding underestimation of lumen area in the CEMRA-derived geometries. We hypothesized that this was due to blurring of edges in the images caused by dilution of contrast agent during the relatively long elliptic centric CEMRA acquisitions, and confirmed this with MRI simulations. Rescaling of CFD models to account for the lumen underestimation improved agreement with the velocity levels seen in the corresponding PCMRI images, but discrepancies in velocity profile shape remained, with CFD tending to over-predict velocity profile skewing. CFD simulations incorporating realistic inlet velocity profiles and non-Newtonian rheology had a negligible effect on velocity profile skewing, suggesting a role for other sources of error or modeling assumptions. In summary, our findings suggest that caution should be exercised when using elliptic-centric CEMRA data as a basis for image-based CFD modeling, and emphasize the importance of comparing image-based CFD models against in vivo data whenever possible.

  9. Investigation on the Use of a Multiphase Eulerian CFD solver to simulate breaking waves

    DEFF Research Database (Denmark)

    Tomaselli, Pietro D.; Christensen, Erik Damgaard

    2015-01-01

    investigation on a CFD model capable of handling this problem. The model is based on a solver, available in the open-source CFD toolkit OpenFOAM, which combines the Eulerian multi-fluid approach for dispersed flows with a numerical interface sharpening method. The solver, enhanced with additional formulations...

  10. The IEA Annex 20 Two-Dimensional Benchmark Test for CFD Predictions

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Rong, Li; Cortes, Ines Olmedo

    2010-01-01

    This paper describes a benchmark test which can be used for tests of CFD predictions of room air distribution. The benchmark describes a box-like room with a supply slot along the side wall. Laser-Doppler measurements and hot-wire measurements are given for comparison with the obtained CFD predic...

  11. Numerical CFD Simulation and Test Correlation in a Flight Project Environment

    Science.gov (United States)

    Gupta, K. K.; Lung, S. F.; Ibrahim, A. H.

    2015-01-01

    This paper presents detailed description of a novel CFD procedure and comparison of its solution results to that obtained by other available CFD codes as well as actual flight and wind tunnel test data pertaining to the GIII aircraft, currently undergoing flight testing at AFRC.

  12. Design of 500kW grate fired test facility using CFD

    DEFF Research Database (Denmark)

    Rosendahl, Lasse Aistrup; Kær, Søren Knudsen; Jørgensen, K.

    2005-01-01

    A 500kW vibrating grate fired test facility for solid biomass fuels has been designed using numerical models including CFD. The CFD modelling has focussed on the nozzle layout and flowpatterns in the lower part of the furnace, and the results have established confidence in the chosen design...

  13. Extending the capabilities of CFD codes to assess ash related problems

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen; Rosendahl, Lasse Aistrup; Baxter, B. B.

    2004-01-01

    This paper discusses the application of FLUENT? in theanalysis of grate-fired biomass boilers. A short description of theconcept used to model fuel conversion on the grate and the couplingto the CFD code is offered. The development and implementation ofa CFD-based deposition model is presented in...

  14. Possible User-Dependent CFD Predictions of Transitional Flow in Building Ventilation

    DEFF Research Database (Denmark)

    Peng, Lei; Nielsen, Peter Vilhelm; Wang, Xiaoxue;

    2016-01-01

    (CFD) codes/software, turbulence models, boundary conditions, numerical schemes and convergent criteria were adopted based on the own CFD experience of each participating team. The largest coefficient of variation is larger than 50% and the largest relative maximum difference of penetration length...

  15. Integration of Engine, Plume, and CFD Analyses in Conceptual Design of Low-Boom Supersonic Aircraft

    Science.gov (United States)

    Li, Wu; Campbell, Richard; Geiselhart, Karl; Shields, Elwood; Nayani, Sudheer; Shenoy, Rajiv

    2009-01-01

    This paper documents an integration of engine, plume, and computational fluid dynamics (CFD) analyses in the conceptual design of low-boom supersonic aircraft, using a variable fidelity approach. In particular, the Numerical Propulsion Simulation System (NPSS) is used for propulsion system cycle analysis and nacelle outer mold line definition, and a low-fidelity plume model is developed for plume shape prediction based on NPSS engine data and nacelle geometry. This model provides a capability for the conceptual design of low-boom supersonic aircraft that accounts for plume effects. Then a newly developed process for automated CFD analysis is presented for CFD-based plume and boom analyses of the conceptual geometry. Five test cases are used to demonstrate the integrated engine, plume, and CFD analysis process based on a variable fidelity approach, as well as the feasibility of the automated CFD plume and boom analysis capability.

  16. Comprehensive Aerodynamic Analysis of a 10 MW Wind Turbine Rotor Using 3D CFD

    DEFF Research Database (Denmark)

    Zahle, Frederik; Bak, Christian; Sørensen, Niels N.;

    2014-01-01

    This article describes a comprehensive aerodynamic analysis carried out on the DTU 10 MW Reference Wind Turbine (DTU 10MW RWT), in which 3D CFD simulations were used to analyse the rotor performance and derive airfoil aerodynamic characteristics for use in aero-elastic simulation tools. The 3D CFD...... airfoil data derived using the Azimuthal Averaging Technique (AAT) was compared to airfoil data based on 2D CFD simulations on airfoil sections in combination with an array of 3D-correction engineering models, which indicated that the model by Chaviaropoulos and Hansen was in best agreement with the 3D...... CFD predictions. BEM simulations on the DTU 10MW RWT using the AAT-based airfoil data were carried out and compared to BEM simulations using the original airfoil data and the 3D CFD results, which showed clear improvements, particularly on the inner part of the rotor. Finally, 3D unsteady Detached...

  17. Anwendung von CFD-Programmen für brandtechnische Berechnungen

    DEFF Research Database (Denmark)

    Carlsson, Jörgen; Husted, Bjarne; Göransson, Ulf;

    2006-01-01

    , in the worst case, may give erroneous results and that the calculation times are too long to be useful in practical fire safety engineering. This article takes a practical view on the use of CFD programmes for fire simulation by looking at two widely used models, SOFIE and FDS.......Computational Fluid Dynamics (CFD) programmes have found widespread use in the combustion and fire science community. These programmes make it possible to take into account phenomena that earlier models could not describe; a typical example being the movement of the smoke in a room. Furthermore, an...... increase in accuracy is expected when using CFD for the calculation of fire development, production of toxic gasses as well as the formation and motion of visibility reducing smoke particles. However not everyone is convinced of the suitability of these CFD techniques. The critics say that CFD programmes...

  18. CFD modeling and experience of waste-to-energy plant burning waste wood

    DEFF Research Database (Denmark)

    Rajh, B.; Yin, Chungen; Samec, N.;

    2013-01-01

    Computational Fluid Dynamics (CFD) is being increasingly used in industry for in-depth understanding of the fundamental mixing, combustion, heat transfer and pollutant formation in combustion processes and for design and optimization of Waste-to-Energy (WtE) plants. In this paper, CFD modeling...... of waste wood combustion in a 13 MW grate-fired boiler in a WtE plant is presented. As a validation effort, the temperature profiles at a number of ports in the furnace are measured and the experimental results are compared with the CFD predictions. In the simulation, a 1D model is developed to simulate...... the conversion of the waste wood in the fuel bed on the grate, which provides the appropriate inlet boundary condition for the freeboard 3D CFD simulation. The CFD analysis reveals the detailed mixing and combustion characteristics in the waste wood-fired furnace, pinpointing how to improve the design...

  19. Computational Fluid Dynamics (CFD Analysis of Natural Convection of Convergent-Divergent Fins in Marine Environments

    Directory of Open Access Journals (Sweden)

    K. Alawadhi

    2014-12-01

    Full Text Available Computational Fluid Dynamics (CFD analysis was carried out for the convergent-divergent fins arranged inline and staggered on the base plate as per the experimental setup provided in the technical paper [1]. This paper reports on the validation of results of modeling and simulation in CFD. The simulation was carried out using the ANSYS 12.0 as the CFD modeling software. The main objective of the CFD analysis was to calculate the temperature distribution on the surface of the base plate and surface of the convergent-divergent fins for the given inline and staggered arrangement of fins due to the effect of natural convection heat transfer for different heat power inputs, and also to compare the CFD results with the experimental results.

  20. Development of Mitsubishi high thermal performance grid. CFD applicability for thermal hydraulic design

    International Nuclear Information System (INIS)

    Mitsubishi has developed a new zircalloy grid spacer for PWR fuel with higher thermal performance. Computational Fluid Dynamics (CFD) evaluation method has been applied for designing of the new lower pressure loss and higher Departure from Nucleate Boiling (DNB) benefit grid spacer. Reduction of pressure loss of grid structures has been examined by CFD. Also, CFD has been developed as a design tool to predict the coolant mixing ability of vane structures, which is to compare the relative peak spot temperatures around fuel rods at the same heat flux condition. Prototype grids were manufactured and several tests, which were pressure loss measurements, cross-flow measurements and freon DNB tests, were conducted to verify CFD predictions. It is concluded that the applicability of the CFD evaluation method for the thermal hydraulic design of the grid is confirmed. (author)

  1. Assessment of Computational Fluid Dynamics (CFD) Models for Shock Boundary-Layer Interaction

    Science.gov (United States)

    DeBonis, James R.; Oberkampf, William L.; Wolf, Richard T.; Orkwis, Paul D.; Turner, Mark G.; Babinsky, Holger

    2011-01-01

    A workshop on the computational fluid dynamics (CFD) prediction of shock boundary-layer interactions (SBLIs) was held at the 48th AIAA Aerospace Sciences Meeting. As part of the workshop numerous CFD analysts submitted solutions to four experimentally measured SBLIs. This paper describes the assessment of the CFD predictions. The assessment includes an uncertainty analysis of the experimental data, the definition of an error metric and the application of that metric to the CFD solutions. The CFD solutions provided very similar levels of error and in general it was difficult to discern clear trends in the data. For the Reynolds Averaged Navier-Stokes methods the choice of turbulence model appeared to be the largest factor in solution accuracy. Large-eddy simulation methods produced error levels similar to RANS methods but provided superior predictions of normal stresses.

  2. Optimization of Hydraulic Machinery Bladings by Multilevel CFD Techniques

    Directory of Open Access Journals (Sweden)

    Thum Susanne

    2005-01-01

    Full Text Available The numerical design optimization for complex hydraulic machinery bladings requires a high number of design parameters and the use of a precise CFD solver yielding high computational costs. To reduce the CPU time needed, a multilevel CFD method has been developed. First of all, the 3D blade geometry is parametrized by means of a geometric design tool to reduce the number of design parameters. To keep geometric accuracy, a special B-spline modification technique has been developed. On the first optimization level, a quasi-3D Euler code (EQ3D is applied. To guarantee a sufficiently accurate result, the code is calibrated by a Navier-Stokes recalculation of the initial design and can be recalibrated after a number of optimization steps by another Navier-Stokes computation. After having got a convergent solution, the optimization process is repeated on the second level using a full 3D Euler code yielding a more accurate flow prediction. Finally, a 3D Navier-Stokes code is applied on the third level to search for the optimum optimorum by means of a fine-tuning of the geometrical parameters. To show the potential of the developed optimization system, the runner blading of a water turbine having a specific speed n q = 41 1 / min was optimized applying the multilevel approach.

  3. Displaying CFD Solution Parameters on Arbitrary Cut Planes

    Science.gov (United States)

    Pao, S. Paul

    2008-01-01

    USMC6 is a Fortran 90 computer program for post-processing in support of visualization of flows simulated by computational fluid dynamics (CFD). The name "USMC6" is partly an abbreviation of "TetrUSS - USM3D Solution Cutter," reflecting its origin as a post-processor for use with USM3D - a CFD program that is a component of the Tetrahedral Unstructured Software System and that solves the Navier-Stokes equations on tetrahedral unstructured grids. "Cutter" here refers to a capability to acquire and process solution data on (1) arbitrary planes that cut through grid volumes, or (2) user-selected spheroidal, conical, cylindrical, and/or prismatic domains cut from within grids. Cutting saves time by enabling concentration of post-processing and visualization efforts on smaller solution domains of interest. The user can select from among more than 40 flow functions. The cut planes can be trimmed to circular or rectangular shape. The user specifies cuts and functions in a free-format input file using simple and easy-to-remember keywords. The USMC6 command line is simple enough that the slicing process can readily be embedded in a shell script for assembly-line post-processing. The output of USMC6 is a data file ready for plotting.

  4. CFD analysis on a turbulence generator of medium consistency pump

    International Nuclear Information System (INIS)

    Medium concentration paper suspension is a water-air-fibre three phase suspension. It has complicated physical features. When concentration exceeds 7%, it stops flowing and acts like a solid. A generator suspension is installed before the impeller to disturb the flocs and networks to make it start to flow. In this paper, CFD method is adopted to study the effects of the turbulence generator. As there is not a mature model to describe the characteristic of pulp suspension, Newtonian fluid is used to get the general property of the turbulence generator. In the CFD simulation, apparent viscosity of the pulp suspension is used to characterize the mixture. Firstly, numerical method is applied to get the turbulence generator properties in different rotational speed and different viscosity. From another point of view, air contained in the suspension is separate initially by means of centrifugal force. As it is difficult to describe a practical model of pulp suspension, it is simplified to be a water-air two-phase mixture. Several air contents are simulated to study the air distribution in the turbulence generator. The results show that there are three main effects of turbulence generator. Firstly, it has an entrainment effect of the suspension to make it into the pump. Secondly, it stirs the pulp suspension to bring it into flowing. Last, air is centralized in the shaft centre and pre-separated in the turbulence generator. So, the turbulence generator can pre-treat the pulp suspension to make the MC pump transport suspension successfully

  5. Study of Swirl and Tumble Motion using CFD

    Directory of Open Access Journals (Sweden)

    Aravind T

    2012-08-01

    Full Text Available The call for environmentally compatible and economical vehicles, still satisfying demands for high performance, necessitates immense efforts to develop innovative engine concepts. In an Internal Combustion Engine the performance, efficiency and emission formation depends on the formation of air-fuel mixture inside the engine cylinder. The fluid flow dynamics plays an important role for air-fuel mixture preparation to obtain the better engine combustion, performance and efficiency. Due to the extreme conditions inside a typical IC-engine (high combustion temperatures and pressures, precipitation of soot and other combustion products, etc. experimental techniques are sometimes limited in approaching the above mentioned problem. Alternatively, computer simulations (Computational Fluid Dynamics, CFD offer the opportunity to carry out repetitive parameter studies with clearly defined boundary conditions in order to investigate various configurations. We investigate two important, common fluid flow patterns from computational fluid dynamics (CFD simulations, namely, swirl and tumble motion typical of automotive engines. These two parameters represents the fluid flow behaviors occurred inside combustion chamber which influences the air streams to the cylinder during intake stroke and enhances greatly the mixing of air and fuel to give better mixing during compression stoke. In this study we are concerned on the swirl motion of inducted air during the suction stroke and during compression stroke. The results obtain from the numerical analysis can be employed to examine the homogeneity of air-fuel mixture structure for better combustion process and engine performance.

  6. Application of CFD Codes in Nuclear Reactor Safety Analysis

    Directory of Open Access Journals (Sweden)

    T. Höhne

    2010-01-01

    Full Text Available Computational Fluid Dynamics (CFD is increasingly being used in nuclear reactor safety (NRS analyses as a tool that enables safety relevant phenomena occurring in the reactor coolant system to be described in more detail. Numerical investigations on single phase coolant mixing in Pressurised Water Reactors (PWR have been performed at the FZD for almost a decade. The work is aimed at describing the mixing phenomena relevant for both safety analysis, particularly in steam line break and boron dilution scenarios, and mixing phenomena of interest for economical operation and the structural integrity. For the experimental investigation of horizontal two phase flows, different non pressurized channels and the TOPFLOW Hot Leg model in a pressure chamber was build and simulated with ANSYS CFX. In a common project between the University of Applied Sciences Zittau/Görlitz and FZD the behaviour of insulation material released by a LOCA released into the containment and might compromise the long term emergency cooling systems is investigated. Moreover, the actual capability of CFD is shown to contribute to fuel rod bundle design with a good CHF performance.

  7. CFD Simulation of Spent Fuel in a Dry Storage System

    International Nuclear Information System (INIS)

    The spent fuel pool is expected to be full in few years. It is a serious problem one should not ignore. The dry storage type is considered as the interim storage system in Korea. The system stores spent fuel in a storage canister filled with an inert gas and the canister is cooled by a natural convection system using air or helium, radiation, and conduction. The spent fuel is heated by decay heat. The spent fuel is allowed to cool under a limiting temperature to avoid a fuel failure. Recently, the thermal hydraulic characteristics for a single bundle of the spent fuel were investigated through a CFD simulation. It would be of great interest to investigate the maximum fuel temperature in a dry storage system. The present paper deals with the thermal hydraulic characteristics of spent fuel for a dry storage system using the CFD method. A 3-D thermal flow simulation was carried out to predict the temperature of spent fuel. A dry storage system composed of 32 fuel bundles was modeled. The inlet temperature of the outer bundle is higher and that of inner bundle, however, is higher at the outlet. In a single fuel assembly, a center temperature of the fuel assembly was higher than elsewhere

  8. CFD analysis of jet mixing in low NOx flametube combustors

    Science.gov (United States)

    Talpallikar, M. V.; Smith, C. E.; Lai, M. C.; Holdeman, J. D.

    1991-01-01

    The Rich-burn/Quick-mix/Lean-burn (RQL) combustor was identified as a potential gas turbine combustor concept to reduce NO(x) emissions in High Speed Civil Transport (HSCT) aircraft. To demonstrate reduced NO(x) levels, cylindrical flametube versions of RQL combustors are being tested at NASA Lewis Research Center. A critical technology needed for the RQL combustor is a method of quickly mixing by-pass combustion air with rich-burn gases. Jet mixing in a cylindrical quick-mix section was numerically analyzed. The quick-mix configuration was five inches in diameter and employed twelve radial-inflow slots. The numerical analyses were performed with an advanced, validated 3-D Computational Fluid Dynamics (CFD) code named REFLEQS. Parametric variation of jet-to-mainstream momentum flux ratio (J) and slot aspect ratio was investigated. Both non-reacting and reacting analyses were performed. Results showed mixing and NO(x) emissions to be highly sensitive to J and slot aspect ratio. Lowest NO(x) emissions occurred when the dilution jet penetrated to approximately mid-radius. The viability of using 3-D CFD analyses for optimizing jet mixing was demonstrated.

  9. Qualitative CFD for Rapid Learning in Industrial and Academic Applications

    Science.gov (United States)

    Variano, Evan

    2010-11-01

    We present a set of tools that allow CFD to be used at an early stage in the design process. Users can rapidly explore the qualitative aspects of fluid flow using real-time simulations that react immediately to design changes. This can guide the design process by fostering an intuitive understanding of fluid dynamics at the prototyping stage. We use an extremely stable Navier-Stokes solver that is available commercially (and free to academic users) plus a custom user interface. The code is designed for the animation and gaming industry, and we exploit the powerful graphical display capabilities to develop a unique human-machine interface. This interface allows the user to efficiently explore the flow in 3D + real time, fostering an intuitive understanding of steady and unsteady flow patterns. There are obvious extensions to use in an academic setting. The trade-offs between accuracy and speed will be discussed in the context of CFD's role in design and education.

  10. A CFD Simulation Process for Fast Reactor Fuel Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Kurt D. Hamman; Ray A. Berry

    2010-09-01

    A CFD modeling and simulation process for large-scale problems using an arbitrary fast reactor fuel assembly design was evaluated. Three-dimensional flow distributions of sodium for several fast reactor fuel assembly pin spacing configurations were simulated on high performance computers using commercial CFD software. This research focused on 19-pin fuel assembly “benchmark” geometry, similar in design to the Advanced Burner Test Reactor, where each pin is separated by helical wire-wrap spacers. Several two-equation turbulence models including the k–e and SST (Menter) k–? were evaluated. Considerable effort was taken to resolve the momentum boundary layer, so as to eliminate the need for wall functions and reduce computational uncertainty. High performance computers were required to generate the hybrid meshes needed to predict secondary flows created by the wire-wrap spacers; computational meshes ranging from 65 to 85 million elements were common. A general validation methodology was followed, including mesh refinement and comparison of numerical results with empirical correlations. Predictions for velocity, temperature, and pressure distribution are shown. The uncertainty of numerical models, importance of high fidelity experimental data, and the challenges associated with simulating and validating large production-type problems are presented.

  11. A CFD simulation process for fast reactor fuel assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Hamman, Kurt D., E-mail: Kurt.Hamman@inl.go [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-3840 (United States); Berry, Ray A. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-3840 (United States)

    2010-09-15

    A CFD modeling and simulation process for large-scale problems using an arbitrary fast reactor fuel assembly design was evaluated. Three-dimensional flow distributions of sodium for several fast reactor fuel assembly pin spacing configurations were simulated on high performance computers using commercial CFD software. This research focused on 19-pin fuel assembly 'benchmark' geometry, similar in design to the Advanced Burner Test Reactor, where each pin is separated by helical wire-wrap spacers. Several two-equation turbulence models including the k-{epsilon} and SST (Menter) k-{omega} were evaluated. Considerable effort was taken to resolve the momentum boundary layer, so as to eliminate the need for wall functions and reduce computational uncertainty. High performance computers were required to generate the hybrid meshes needed to predict secondary flows created by the wire-wrap spacers; computational meshes ranging from 65 to 85 million elements were common. A general validation methodology was followed, including mesh refinement and comparison of numerical results with empirical correlations. Predictions for velocity, temperature, and pressure distribution are shown. The uncertainty of numerical models, importance of high fidelity experimental data, and the challenges associated with simulating and validating large production-type problems are presented.

  12. CFD Simulation of Spent Fuel in a Dry Storage System

    Energy Technology Data Exchange (ETDEWEB)

    Kwack, Young Kyun; In, Wang Kee; Shin, Chang Hwan; Chun, Tae Hyun; Kook, Dong Hak [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The spent fuel pool is expected to be full in few years. It is a serious problem one should not ignore. The dry storage type is considered as the interim storage system in Korea. The system stores spent fuel in a storage canister filled with an inert gas and the canister is cooled by a natural convection system using air or helium, radiation, and conduction. The spent fuel is heated by decay heat. The spent fuel is allowed to cool under a limiting temperature to avoid a fuel failure. Recently, the thermal hydraulic characteristics for a single bundle of the spent fuel were investigated through a CFD simulation. It would be of great interest to investigate the maximum fuel temperature in a dry storage system. The present paper deals with the thermal hydraulic characteristics of spent fuel for a dry storage system using the CFD method. A 3-D thermal flow simulation was carried out to predict the temperature of spent fuel. A dry storage system composed of 32 fuel bundles was modeled. The inlet temperature of the outer bundle is higher and that of inner bundle, however, is higher at the outlet. In a single fuel assembly, a center temperature of the fuel assembly was higher than elsewhere.

  13. Analysis of a waste-heat boiler by CFD simulation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yongziang; Jokilaakso, A. [Helsinki Univ. of Technology, Otaniemi (Finland)

    1996-12-31

    Waste-heat boilers play important roles in the continuous operation of a smelter and in the conservation of energy. However, the fluid flow and heat transfer behaviour has not been well studied, concerning the boiler performance and design. This presentation describes simulated gas flow and heat transfer of a waste-heat boiler in the Outokumpu copper flash smelting process. The governing transport equations for the conservation of mass, momentum and enthalpy were solved with a commercial CFD-code PHOENICS. The standard k-{epsilon} turbulence model and a composite-flux radiation model were used in the computations. The computational results show that the flow is strongly recirculating and distinctly three-dimensional in most part of the boiler, particularly in the radiation section. The predicted flow pattern and temperature distribution were in a good agreement with laboratory models and industrial measurements. The results provide detailed information of flow pattern, the temperature distribution and gas cooling efficiency. The CFD proved to be a useful tool in analysing the boiler operation. (author)

  14. OPTIMIZATION OF A WAVE CANCELLATION MULTIHULL SHIP USING CFD TOOLS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A simple CFD tool, coupled to a discrete surface representation and a gradient-based optimization procedure, is applied to the design of optimal hull forms and optimal arrangement of hulls for a wave cancellation multihull ship. The CFD tool, which is used to estimate the wave drag, is based on the zeroth-order slender ship approximation. The hull surface is represented by a triangulation, and almost every grid point on the surface can be used as a design variable. A smooth surface is obtained via a simplified pseudo-shell problem. The optimal design process consists of two steps. The optimal center and outer hull forms are determined independently in the first step, where each hull forms are determined independently in the first step, where each hull keeps the same displacement as the original design while the wave drag is minimized. The optimal outer-hull arrangement is determined in the second step for the optimal center and outer hull forms obtained in the first step. Results indicate that the new design can achieve a large wave drag reduction in comparison to the original design configuration.

  15. CFD Modeling of Particulate Matter Dispersion from Kerman Cement Plant

    Directory of Open Access Journals (Sweden)

    M. Panahandeh

    2010-04-01

    Full Text Available "n "n "nBackgrounds and Objectives: The dispersion of particulate matter has been known as the most serious environmental pollution of cement plants. In the present work, dispersion of the particulate matter from stack of Kerman Cement Plant was investigated using Computational Fluid Dynamics (CFD modeling."nMaterials and Methods: In order to study the dispersion of particulate matter from the stack, a calculation domain with dimensions of 8000m × 800m × 400m was considered. The domain was divided to 936781 tetrahedral control volumes. The mixture two-phase model was employed to model the interaction of the particulate matter (dispersed phase and air (continuous phase. The Large Eddy Simulation (LES method was used for turbulence modeling."nResults: The concentration of particulate matter in the whole calculation domain was computed. The predicted concentrations were compared to the measured values from the literature and a good agreement was observed. The predicted concentration profiles at different cross sections were analyzed."nConclusion:The results of the present work showed that CFD is a useful tool for understanding the dispersion of particulate matter in air. Although the obtained results were promising, more investigations on the properties of the dispersed phase, turbulent parameters and the boundary layer effect is needed to obtain more accurate results.

  16. Study of Swirl and Tumble Motion using CFD

    Directory of Open Access Journals (Sweden)

    Abhilash M Bharadwaj

    2013-06-01

    Full Text Available The call for environmentally compatible and economical vehicles, still satisfying demands for high performance, necessitates immense efforts to develop innovative engine concepts. In an Internal Combustion Engine the performance, efficiency and emission formation depends on the formation of air-fuel mixture inside the engine cylinder. The fluid flow dynamics plays an important role for air-fuel mixture preparation to obtain the better engine combustion, performance and efficiency. Due to the extreme conditions inside a typical IC-engine (high combustion temperatures and pressures, precipitation of soot and other combustion products, etc. experimental techniques are sometimes limited in approaching the above mentioned problem. Alternatively, computer simulations (Computational Fluid Dynamics, CFD offer the opportunity to carry out repetitive parameter studies with clearly defined boundary conditions in order to investigate various configurations. We investigate two important, common fluid flow patterns from computational fluid dynamics (CFD simulations, namely, swirl and tumble motion typical of automotive engines. These two parameters represents the fluid flow behaviors occurred inside combustion chamber which influences the air streams to the cylinder during intake stroke and enhances greatly the mixing of air and fuel to give better mixing during compression stoke. In this study we are concerned on the swirl motion of inducted air during the suction stroke and during compression stroke. The results obtain from the numerical analysis can be employed to examine the homogeneity of air-fuel mixture structure for better combustion process and engine performance.

  17. Unstructured CFD and Noise Prediction Methods for Propulsion Airframe Aeroacoustics

    Science.gov (United States)

    Pao, S. Paul; Abdol-Hamid, Khaled S.; Campbell, Richard L.; Hunter, Craig A.; Massey, Steven J.; Elmiligui, Alaa A.

    2006-01-01

    Using unstructured mesh CFD methods for Propulsion Airframe Aeroacoustics (PAA) analysis has the distinct advantage of precise and fast computational mesh generation for complex propulsion and airframe integration arrangements that include engine inlet, exhaust nozzles, pylon, wing, flaps, and flap deployment mechanical parts. However, accurate solution values of shear layer velocity, temperature and turbulence are extremely important for evaluating the usually small noise differentials of potential applications to commercial transport aircraft propulsion integration. This paper describes a set of calibration computations for an isolated separate flow bypass ratio five engine nozzle model and the same nozzle system with a pylon. These configurations have measured data along with prior CFD solutions and noise predictions using a proven structured mesh method, which can be used for comparison to the unstructured mesh solutions obtained in this investigation. This numerical investigation utilized the TetrUSS system that includes a Navier-Stokes solver, the associated unstructured mesh generation tools, post-processing utilities, plus some recently added enhancements to the system. New features necessary for this study include the addition of two equation turbulence models to the USM3D code, an h-refinement utility to enhance mesh density in the shear mixing region, and a flow adaptive mesh redistribution method. In addition, a computational procedure was developed to optimize both solution accuracy and mesh economy. Noise predictions were completed using an unstructured mesh version of the JeT3D code.

  18. CFD Verification of 5x5 Rod Bundle with Mixing Vane Spacer Grids

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sungkew; Jang, Hyungwook; Lim, Jongseon; Park, Eungjun; Nahm, Keeyil [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    Results of the CHF test are used for determining the CHF correlation, which is used to evaluate the thermal margin in the reactor core. Computational fluid dynamics (CFD) has been used to save the time and cost for experimental tests, components design and complicated phenomena in all industries including the reactor coolant system. L. D. Smith et al. applied the CFD methodology in a 5x5 rod bundle with the mixing vane spacer grid using the renormalization group (RNG) k-epsilon model. This CFD model agreed reasonably well with the test data. M. E. Conner et al. conducted experiments to validate the CFD methodology for the single-phase flow conditions in PWR fuel assemblies. In this validation case, the CFD code predicted very similar flow field structures as the test data. In this study, a CFD simulation under single-phase flow condition was conducted for one specific condition in a thermal mixing flow test of 5x5 rod bundle with some mixing vane spacer grids. In this study, a CFD simulation under a single-phase flow condition was conducted for one specific condition in a thermal mixing flow test of 5x5 rod bundle with the mixing vane spacer grids to verify the applicability of the CFD model for predicting the outlet temperature distribution. FLUENT 14.5 Version was used in this CFD analysis. For the successful prediction of the wall bounded turbulent flows, the y+ with 3 prism layers was determined within 5. At this time, k-epsilon standard turbulence model was used. The temperature distribution of CFD for each sub-channel at the outlet region of test bundle showed the difference approximately within 1.1% and 0.2% while comparing to that of test and sub-channel analysis code, respectively.

  19. CFD Verification of 5x5 Rod Bundle with Mixing Vane Spacer Grids

    International Nuclear Information System (INIS)

    Results of the CHF test are used for determining the CHF correlation, which is used to evaluate the thermal margin in the reactor core. Computational fluid dynamics (CFD) has been used to save the time and cost for experimental tests, components design and complicated phenomena in all industries including the reactor coolant system. L. D. Smith et al. applied the CFD methodology in a 5x5 rod bundle with the mixing vane spacer grid using the renormalization group (RNG) k-epsilon model. This CFD model agreed reasonably well with the test data. M. E. Conner et al. conducted experiments to validate the CFD methodology for the single-phase flow conditions in PWR fuel assemblies. In this validation case, the CFD code predicted very similar flow field structures as the test data. In this study, a CFD simulation under single-phase flow condition was conducted for one specific condition in a thermal mixing flow test of 5x5 rod bundle with some mixing vane spacer grids. In this study, a CFD simulation under a single-phase flow condition was conducted for one specific condition in a thermal mixing flow test of 5x5 rod bundle with the mixing vane spacer grids to verify the applicability of the CFD model for predicting the outlet temperature distribution. FLUENT 14.5 Version was used in this CFD analysis. For the successful prediction of the wall bounded turbulent flows, the y+ with 3 prism layers was determined within 5. At this time, k-epsilon standard turbulence model was used. The temperature distribution of CFD for each sub-channel at the outlet region of test bundle showed the difference approximately within 1.1% and 0.2% while comparing to that of test and sub-channel analysis code, respectively

  20. CFD SIMULATIONS OF JOINT URBAN ATMOSPHERE DISPERSION FIELD STUDY 2003

    Energy Technology Data Exchange (ETDEWEB)

    Lee, R L; Humphreys, T D; Chan, S T

    2004-03-31

    In the Spring of 2003, a series of dispersion field experiments (Joint Urban 2003) were conducted at Oklahoma City. These experiments were complimentary to the URBAN 2000 field studies at Salt Lake City (Allwine, et. al, 2002) in that they will provide a second set of comprehensive field data for evaluation of CFD as well as for other dispersion models. In contrast to the URBAN 2000 experiments that were conducted entirely at night, these new field studies took place during both daytime and nighttime thus including the possibility of convective as well as stable atmospheric conditions. Initially several CFD modeling studies were performed to provide guidance for the experimental team in the selection of release sites and in the deployment of wind and concentration sensors. Also, while meteorological and concentration measurements were taken over the greater Oklahoma City urban area, our CFD calculations were focused on the near field of the release point. The proximity of the source to a large commercial building and to the neighboring buildings several of which have multi-stories, present a significant challenge even for CFD calculations involving grid resolutions as fine as 1 meter. A total of 10 Intensive Observations Periods (IOP's) were conducted within the 2003 field experiments. SF{sub 6} releases in the form of puffs or continuous sources were disseminated over 6 daytime and 4 nighttime episodes. Many wind and concentration sensors were used to provide wind and SF{sub 6} data over both long and short time-averaging periods. In addition to the usual near surface measurements, data depicting vertical profiles of wind and concentrations adjacent to the outside walls several building were also taken. Also of interest were observations of the trajectory of balloons that were released closed to the tracer release area. Many of the balloons released exhibit extremely quick ascents up from ground level to the top of buildings, thus implying highly convective