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Sample records for blowers nozzles geometria

  1. Optimum geometry for boiler soot blowers nozzles; Geometria optima de toberas para deshollinadores de caldera

    Energy Technology Data Exchange (ETDEWEB)

    Espinoza Garza, Jesus; Garcia Tinoco, Guillermo J.; Martinez Flores, Jose Oscar [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1989-12-31

    For boiler soot blowing converging-diverging nozzles are employed, whose function is to convert thermal energy of a gas into kinetic energy to remove the deposits that adhere to the heat exchanger surfaces. In this paper are described the experimental equipment and the methods for flow, dynamic pressure, discharge velocity and air expansion factor calculation in each nozzle, as a function of its design geometry, utilizing air from a five stage centrifugal compressor. The graphic analysis of the results, concludes that the most efficient nozzles are not the ones than develop the greatest velocity, but the ones of highest dynamic pressure at the outlet. The nozzle geometry that allows obtaining the maximum dynamic air pressure at the discharge is A{sub 2}/A{sub g}=1.3676 [Espanol] Para el deshollinado de calderas se utilizan las toberas convergentes-divergentes, cuya funcion es convertir la energia termica de un gas en energia cinetica para remover los depositos que se adhieren a las superficies de intercambio de calor. En este trabajo se describen el equipo experimental y los metodos de calculo para flujo, presion dinamica, velocidad a la descarga y factor de expansion del aire en cada tobera, como funcion de su geometria de diseno. Durante la experimentacion se evaluaron siete disenos diferentes de toberas, empleando aire de un compresor centrifugo de cinco etapas. Del analisis grafico de los resultados, se concluye que las toberas mas eficientes no son las que desarrollan mayor velocidad sino las de mayor presion dinamica de la salida. La geometria de tobera que permite obtener la maxima presion dinamica del aire a la descarga es A{sub 2}/A{sub g} = 1.3676.

  2. Study of Jet-Propulsion System Comprising Blower, Burner, and Nozzle

    Science.gov (United States)

    Hall, Eldon W

    1944-01-01

    A study was made of the performance of a jet-propulsion system composed of an engine-driven blower, a combustion chamber, and a discharge nozzle. A simplified analysis is made of this system for the purpose of showing in concise form the effect of the important design variables and operating conditions on jet thrust, thrust horsepower, and fuel consumption. Curves are presented that permit a rapid evaluation of the performance of this system for a range of operating conditions. The performance for an illustrative case of a power plant of the type under consideration id discussed in detail. It is shown that for a given airplane velocity the jet thrust horsepower depends mainly on the blower power and the amount of fuel burned in the jet; the higher the thrust horsepower is for a given blower power, the higher the fuel consumption per thrust horsepower. Within limits the amount of air pumped has only a secondary effect on the thrust horsepower and efficiency. A lower limit on air flow for a given fuel flow occurs where the combustion-chamber temperature becomes excessive on the basis of the strength of the structure. As the air-flow rate is increased, an upper limit is reached where, for a given blower power, fuel-flow rate, and combustion-chamber size, further increase in air flow causes a decrease in power and efficiency. This decrease in power is caused by excessive velocity through the combustion chamber, attended by an excessive pressure drop caused by momentum changes occurring during combustion.

  3. Geometria responsiva

    Directory of Open Access Journals (Sweden)

    Graziano Mario Valenti

    2012-06-01

    Full Text Available Il progetto industriale, così come quello architettonico, manifesta un’attenzione crescente verso comportamenti di tipo “responsivo”. Gli oggetti, sia nella piccola scala del Design, sia nella più grande scala dell’architettura, sono sempre più frequentemente dotati di un’intelligenza digitale, una logica comportamentale che consente loro di interagire con le persone che li fruiscono. Gli oggetti e gli spazi a carattere “responsivo” caratterizzeranno senza dubbio il prossimo futuro e questo processo di trasformazione riguarderà in modo particolare anche la forma e dunque la geometria che la forma stessa astrae e descrive. E’ necessario dunque un nuovo modo di immaginare e di progettare modelli dinamici. La modellazione parametrica è un valido ausilio in questo processo, ma il progettista, più del solito, dovrà necessariamente confrontarsi con la geometria. Lo studio qui illustrato sperimenta la parametrizzazione finalizzata alla trasformazione dinamica di superfici piane in superfici coniche.

  4. Ring blowers. Ring blower

    Energy Technology Data Exchange (ETDEWEB)

    Nakahara, Y.; Okamura, T.; Takahashi, M. (Fuji Electric Co. Ltd., Tokyo (Japan))

    1991-06-10

    Features, structures and several products of ring blowers were outlined. The ring blower is featured by its medium characteristics because it is higher in air pressure than a turboblower and larger in airflow than a vane blower, and it is applicable flexibly to not only air blasting but various industrial fields such as suction transfer. As several products corresponding to various fields, the followings were outlined: the low noise type with optimum shapes of inlet, outlet and casing cover for reducing noises by 10 dB or more, the heat resistant, water-tight and explosion-proof types suitable for severe environmental conditions, the multi-voltage type for every country served at different voltages, the high air pressure type with two pressure rise stages, and the large airflow type with a wide impeller. In addition, as special use products, the glass fiber reinforced unsatulated polyester ring blower for respiration apparatus, and the variable speed blushless DC motor-driven one for medical beds were outlined. 2 refs., 9 figs., 1 tab.

  5. Nozzle

    Science.gov (United States)

    Chen, Alexander G.; Cohen, Jeffrey M.

    2009-06-16

    A fuel injector has a number of groups of nozzles. The groups are generally concentric with an injector axis. Each nozzle defines a gas flowpath having an outlet for discharging a fuel/air mixture jet. There are means for introducing the fuel to the air. One or more groups of the nozzles are oriented to direct the associated jets skew to the injector axis.

  6. Fractais : da geometria à videoarte

    OpenAIRE

    2013-01-01

    A descoberta da geometria fractal é datada de meados do séc. XX. É conhecida como a geometria da natureza já que permite descrever muitos fenómenos naturais que apresentam irregularidades que são impossíveis de descrever através dos princípios da geometria tradicional. O aparecimento de novas tecnologias digitais veio alterar o modo como a arte é encarada. Este trabalho pretende demonstrar possibilidades de integração da geometria fractal e a Teoria do Caos na criação de videoarte, b...

  7. Blowers; Ventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, C. [Forschungsstelle fuer Energiewirtschaft, Muenchen (Germany); Pfitzner, G. [Forschungsstelle fuer Energiewirtschaft, Muenchen (Germany)

    1994-11-01

    In the framework of the partial project ``Interdisciplinary Technologies`, Vol. 8.06 reports on problems of blower engineering: System requiremsnts (applications of blowers); Technical descriptions (characteristics, capacity, performance, cost, similarity laws, types, control processes); Descriptions of systems and plants (design, circuiting); Data compilations and data sheets; Summary analysis. (HW) [Deutsch] Im Rahmen der Teilprojekte ``Querschnittstechniken`` wird hier in Band 8.06 ueber Probleme der Ventilatortechnik berichtet. - Systemanforderungen (Einsatzbereiche von Ventilatoren); - Technikbeschreibung (Kennlinien, Leistung, Wirkungsgrad, Kosten, Aehnlichkeitsgesetze, Bauartenuebersicht, Regelverfahren); - Anlagen und Systembeschreibung (Auslegung, Schaltungsverfahren); - Datensammlung und Datenblatt; - Uebergreifende Analyse. (HW)

  8. Constant-pressure Blowers

    Science.gov (United States)

    Sorensen, E

    1940-01-01

    The conventional axial blowers operate on the high-pressure principle. One drawback of this type of blower is the relatively low pressure head, which one attempts to overcome with axial blowers producing very high pressure at a given circumferential speed. The Schicht constant-pressure blower affords pressure ratios considerably higher than those of axial blowers of conventional design with approximately the same efficiency.

  9. Nozzle and blading geometries of free running radial blowers. Pt. 1. Numeric investigations influencing the flow field; Duesen- und Beschaufelungsgeometrie freilaufender Radialventilatoren. T. 1. Numerische Untersuchungen zum Einfluss auf das Stroemungsfeld

    Energy Technology Data Exchange (ETDEWEB)

    Willburger, A.; Lawerenz, M. [Kassel Univ. (Germany). Fachgebiet Stroemungsmaschinen; Hoppe, L. [TLT-Turbo GmbH (Germany)

    2007-12-15

    Free running radial blowers are used in air conditioning, in ventilation and smoke removal. Low production cost is a key aspect, but driving power and performance have recently become important as well. (orig.)

  10. Blower test stand; Luftleistungspruefstand

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2003-04-01

    Blowers move air, but how much air? Extensive measurements are required for assessing blower performance in terms of the actual air flow volume. The most precise results are obtained in a test stand. [German] Luefter bewegen Luft. Aber wie viel wird tatsaechlich bewegt? Fuer die Bestimmung der tatsaechlichen Luftfoerderleistung ist ein grosser Messaufwand notwendig, die praezisesten Ergebnisse bringt ein Luftleistungsmessstand. (orig.)

  11. GEOMETRIA ANALÍTICA COM ENFOQUE COMPUTACIONAL

    OpenAIRE

    Karise Gonçalves Oliveira; Cleber de Souza Alcântara

    2011-01-01

    Pretendemos aumentar o conhecimento com relação a Geometria Analítica, abrangendo conceitos que não são vistos durante o curso técnico, com um estudo mais aprofundado relacionadas com o plano, cônicas e quádricas. O diferencial deste trabalho está na utilização de softwares livres, como GEONExT, que permitem uma melhor compreensão e precisão da geometria objetos estudados.

  12. Variable displacement blower

    Science.gov (United States)

    Bookout, Charles C.; Stotts, Robert E.; Waring, Douglass R.; Folsom, Lawrence R.

    1986-01-01

    A blower having a stationary casing for rotatably supporting a rotor assembly having a series of open ended chambers arranged to close against the surrounding walls of the casing. Pistons are slidably mounted within each chamber with the center of rotation of the pistons being offset in regard to the center of rotation of the rotor assembly whereby the pistons reciprocate in the chambers as the rotor assembly turns. As inlet port communicates with the rotor assembly to deliver a working substance into the chamber as the pistons approach a top dead center position in the chamber while an outlet port also communicates with the rotor to exhaust the working substance as the pistons approach a bottom dead center position. The displacement of the blower is varied by adjusting the amount of eccentricity between the center of rotation of the pistons and the center of rotation of the rotor assembly.

  13. Blowers. 2. ed.; Ventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Bommes, L.; Fricke, J.; Grundmann, R. (eds.)

    2003-07-01

    Economic efficiency, high availability, materials and wear resistance are still the main goals of development on the blower sector, together with noise reduction. Subjects: (a) Modified methods for calculation and design of axial and radial blowers; (b) Test stand measurements of aerodynamic and acoustic performance; (c) Problems of experimental determination of performance data; (d) effects of the installation conditions and thre resulting electric field disturbances influencing the aerodynamic and acoustic blower characteristics; (e) Centrifugal and vibration loads on the rotors; (f) Determination of the axial thrust of radial blowers; (g) Special designs and specifications for special applications; (h) Blower noise: Sources, measurement, prediction; (i) Noise reduction measures; (j) Specific aspects of working with solid-gas mixtures. The book presents a wide range of research findings, modern design methods and problem solutions. Fundamentals of fluidics, thermodynamics, similarity mechanics and aeroacoustics are discussed in detail in as far as they are of importance for blower construction. This second edition was revised with a view to practical applicability and to the latest state of research. (orig.) [German] Ventilatoren sind zentraler Bestandteil aller lueftungstechnischen Anlagen- und Geraetesysteme und daher fuer deren Funktionstuechtigkeit von ausschlaggebender Bedeutung. Sie zaehlen nach der heute gueltigen Definition zu den Stroemungsmaschinen, in denen mechanische Energie in Stroemungsenergie umgewandelt wird. Nach der Norm reicht bei Ventilatoren der Bereich der Druckerhoehung des Foerdermediums zwischen Ventilatoreintritt und -austritt bis zu 30 000 Pa, entsprechend einem Druckverhaeltnis bis zu 1,3. Hauptentwicklungsziele bei Ventilatoren sind nach wie vor die Steigerung der Wirtschaftlichkeit, Betriebssicherheit, Werkstoffbelastbarkeit und Verschleissfestigkeit. Darueber hinaus spielen im Rahmen des staendig wachsenden Umweltbewusstseins

  14. [Respiratory function in glass blowers].

    Science.gov (United States)

    Zuskin, E; Butković, D; Mustajbegović, J

    1992-01-01

    The prevalence of chronic and acute respiratory symptoms and diseases and changes in lung function in a group of 80 glass blowers have been investigated. In addition a group of 80 not exposed workers was used as a control group for respiratory symptoms and diseases. In glass blowers, there was significant increase in prevalence of chronic bronchitis, nasal catarrh, and sinusitis than in the controls. Glass blowers exposed for more and less than 10 years had similar prevalences of respiratory symptoms. A large number of glass blowers complained of acute across-shift symptoms. Significant increase in FVC, FEF50 and FEF25 was documented at the end of the work shift. Comparison with predicted normal values showed that glass blowers had FVC and FEF25 significantly lower than predicted. RV and RV/TLC were significantly increased compared with the predicted normal values. DLCO was within the normal values in most glass blowers. It is concluded that work in the glass blower industry is likely to lead the development of chronic respiratory disorders.

  15. Singularidades de curvas na geometria afim

    OpenAIRE

    Luis Florial Espinoza Sanchez

    2010-01-01

    Neste trabalho estudamos a geometria da evoluta afim e da curva normal afim associada à uma curva plana sem inflexões a partir do tipo de singularidade das funções suporte afim. O principal resultado estabelece que se \\'\\\\gamma\\' é uma curva plana sem inflexões, satisfazendo certas condições genéricas então dois casos podem ocorrer: 1. se p é um ponto da evoluta afim de \\'\\\\gamma\\' em \\'s IND. 0\\' então temos dois casos: se \\'\\\\gamma\\' (\\'s IND. 0\\') é um ponto sextático então, localmente ...

  16. Noise Emission from Laboratory Air Blowers

    Science.gov (United States)

    Rossing, Thomas D.; Windham, Betty

    1978-01-01

    Product noise ratings for a number of laboratory air blowers are reported and several recommendations for reducing laboratory noise from air blowers are given. Relevant noise ratings and methods for measuring noise emission of appliances are discussed. (BB)

  17. Investigations on Experimental Impellers for Axial Blowers

    Science.gov (United States)

    Encke, W.

    1947-01-01

    A selection of measurements obtained on experimental impellers for axial blowers will be reported. In addition to characteristic curves plotted for low and for high peripheral velocities, proportions and blade sections for six different blower models and remarks on the design of blowers will be presented.

  18. Ensino de geometria descritiva: inovando na metodologia

    Directory of Open Access Journals (Sweden)

    Regina Coeli Moraes Kopke

    2001-03-01

    Full Text Available Com base na observação, durante anos de magistério superior, na área de desenho, dos alunos de Engenharia, Matemática, Arquitetura e Artes, quanto às dificuldades encontradas por eles no aprendizado de desenho, em especial da Geometria Descritiva, é que nos propusemos, em 1999, lecionar essa disciplina para os cursos de Arquitetura e Artes, adotando uma metodologia diferente da convencional, para despertar, no aluno, o gosto pela disciplina e o desenvolvimento de uma habilidade pouco trabalhada na escola: a visão espacial. Mostrar para os alunos que essa disciplina não é difícil, mas apenas diferente daquilo que estudaram até então, tornou-se nossa meta. A visão espacial é uma habilidade mental localizada no lado direito do cérebro e, assim, quanto mais lúdica for esta aprendizagem, será mais bem assimilada. A proposta é iniciada no sentido de se trabalhar primeiro com sólidos: neles estarão os pontos, retas e planos normalmente abordados na metodologia convencional, nessa ordem. Como conclusão, tem-se que o importante é ressaltar o grande avanço que a Geometria Descritiva traz para quem quer representar graficamente qualquer coisa. Onde há planejamento, projeto e representação gráfica, aí estará a Geometria Descritiva.During many years observing the teaching of design at the Engineering, Mathematics, Architeture and Arts courses, we can note the difficulties of the students to learn it, specially the descriptive geometry. Because of that, we decided to teach this discipline to the Architeture and Arts courses, using a new metodology to make the students motivated to study and to learn, and trying to develop their their spatial vision. We want to show to the students that this discipline is not so difficult as they think, but show them that is only different. The spatial vision is a mental skill found at the right side of the brain and the more soft the learning is, the more it is assimilated by the brain. The

  19. Increasing loads on mine centrifugal blowers

    Energy Technology Data Exchange (ETDEWEB)

    Kovalevskaya, V.I.; Pak, V.V. (Donetskii Politekhnicheskii Institut (USSR))

    1991-03-01

    Increasing output of blowers for ventilation of deep coal mines by enlarging their dimensions and increasing revolution rate is uneconomic and technically complicated. Optimization of aerodynamic characteristics of the blowers is most economic. Effects of blower blade geometry (shape and cross-section) on blower output, air pressure and efficiency are analyzed. On the basis of Euler's equations a method is discussed for determining optimum aerodynamic parameters of the modified blade geometry that guarantees the most economic blower operation. 7 refs.

  20. Ambientes de Geometria Dinâmica: Potencialidades e Imprevistos

    OpenAIRE

    2012-01-01

    Esse artigo apresenta resultados de uma pesquisa que teve como objetivo analisar as contribuições pedagógicas de um ambiente de geometria dinâmica através do trabalho em um grupo de estudos formado por futuros professores de matemática. O grupo se reuniu para ler e discutir artigos científicos, explorar um software de geometria dinâmica e elaborar uma oficina para alunos do ensino médio de uma escola pública. O artigo destaca episódios oriundos das atividades elaboradas pelo grupo as quais in...

  1. VARIABLE SPEED INTEGRATED INTELLIGENT HVAC BLOWER

    Energy Technology Data Exchange (ETDEWEB)

    Shixiao Wang; Herman Wiegman; Wilson Wu; John Down; Luana Iorio; Asha Devarajan; Jing Wang; Ralph Carl; Charlie Stephens; Jeannine Jones; Paul Szczesny

    2001-11-14

    This comprehensive topical report discusses the key findings in the development of a intelligent integrated blower for HVAC applications. The benefits of rearward inclined blades over that of traditional forward inclined blades is well documented and a prototype blower design is presented. A comparison of the proposed blower to that of three typical units from the industry is presented. The design of the blower housing is also addressed and the impact of size limitations on static efficiency is discussed. Issues of air flow controllability in the rearward inclined blower is addressed and a solution to this problem is proposed. Several motor design options are discussed including inside-out radial flux designs and novel axial flux designs, all are focused on the various blower needs. The control of the motor-blower and airflow through the use of a high density inverter stage and modern digital signal processor is presented. The key technical challenges of the approach are discussed. The use of the motor as a sensor in the larger heating/ventilating system is also discussed. Diagnostic results for both the motor itself and the blower system are presented.

  2. 33 CFR 154.826 - Vapor compressors and blowers.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Vapor compressors and blowers....826 Vapor compressors and blowers. (a) Each inlet and outlet to a compressor or blower which handles...) Excessive shaft bearing temperature. (d) If a centrifugal compressor, fan, or lobe blower handles vapor...

  3. Par de Curvas no Plano: Geometria da Bicicleta

    OpenAIRE

    2011-01-01

    O principal objetivo deste trabalho é estudar as curvas geradas pelas rodas traseira e dianteira de uma bicicleta do ponto de vista da Geometria diferencial. The main objective is to study the curves generated by the front and rear wheels of a bicycle from the standpoint of differential geometry.

  4. Air injection vacuum blower noise control

    Energy Technology Data Exchange (ETDEWEB)

    Mose, Tyler L.A.; Faszer, Andrew C. [Noise Solutions Inc. (Canada)], email: tmose@noisesolutions.com, email: afaszer@noisesolutions.com

    2011-07-01

    Air injection vacuum blowers, with applications in waste removal, central vacuum systems, and aeration systems, are widely used when high vacuum levels are required. Noise generated by those blowers must be addressed for operator health and residential disturbance. This paper describes a project led by Noise Solutions Inc., to identify noise sources in a blower, and design and test a noise mitigation system. First the predominant noise sources in the blower must be determined, this is done with a sound level meter used to quantify the contribution of each individual noise source and the dominant tonal noise from the blower. Design of a noise abatement system must take into account constraints arising from blower mobile use, blower optimal performance, and the resulting overall vibration of the structure. The design was based on calculations from the sound attenuation of a reactive expansion chamber and two prototypes of custom silencers were then tested, showing a significant noise reduction both in total sound levels and tonal noise.

  5. Regenerative Blower for EVA Suit Ventilation Fan

    Science.gov (United States)

    Izenson, Michael G.; Chen, Weibo; Paul, Heather L.

    2010-01-01

    Portable life support systems in future space suits will include a ventilation subsystem driven by a dedicated fan. This ventilation fan must meet challenging requirements for pressure rise, flow rate, efficiency, size, safety, and reliability. This paper describes research and development that showed the feasibility of a regenerative blower that is uniquely suited to meet these requirements. We proved feasibility through component tests, blower tests, and design analysis. Based on the requirements for the Constellation Space Suit Element (CSSE) Portable Life Support System (PLSS) ventilation fan, we designed the critical elements of the blower. We measured the effects of key design parameters on blower performance using separate effects tests, and used the results of these tests to design a regenerative blower that will meet the ventilation fan requirements. We assembled a proof-of-concept blower and measured its performance at sub-atmospheric pressures that simulate a PLSS ventilation loop environment. Head/flow performance and maximum efficiency point data were used to specify the design and operating conditions for the ventilation fan. We identified materials for the blower that will enhance safety for operation in a lunar environment, and produced a solid model that illustrates the final design. The proof-of-concept blower produced the flow rate and pressure rise needed for the CSSE ventilation subsystem while running at 5400 rpm, consuming only 9 W of electric power using a non-optimized, commercial motor and controller and inefficient bearings. Scaling the test results to a complete design shows that a lightweight, compact, reliable, and low power regenerative blower can meet the performance requirements for future space suit life support systems.

  6. Scramjet Nozzles

    Science.gov (United States)

    2010-09-01

    integration et gestion thermique ) 14. ABSTRACT The lecture is given in four parts, each being a step in the process of nozzle design, and within each part...project and applied to the conceptual design of a Mach 3.5 transport aircraft. The result is depicted in figure 4. The central feature of the concept is

  7. VARIABLE SPEED INTEGRATED INTELLIGENT HVAC BLOWER

    Energy Technology Data Exchange (ETDEWEB)

    Herman Wiegman; Charlie Stephens; Xiaoyue Liu; Ralph Carl; Sunny Zhuang; Paul Szczesny; Kamron Wright

    2003-09-23

    This comprehensive topical report discusses the key findings in the development of an advanced blower for HVAC applications. The benefits of rearward inclined blades over that of traditional forward inclined blades is well documented, and several prototype wheels are demonstrated in various housings. A comparison of retrofitted blowers to that of three typical units from the industry is presented. The design and modification of the blower housing is addressed and the impact of size limitations on static efficiency is discussed. The roadmap to rearward-inclined wheel technology insertion is presented and typical static efficiency gains are documented.

  8. A geometria a partir de Euclides direcionada para o cálculo diferencial e integral

    OpenAIRE

    Goulart, Lenir Joaquina

    2002-01-01

    Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção Desenvolve-se uma investigação científica considerando a História da Matemática como uma importante alavanca conceitual fundamentada em alguns aspectos da Geometria em Euclides e em alguns aspectos da Geometria em Hilbert. Investiga-se a evolução dos Fundamentos da Geometria de Euclides com vistas à confecção de material de apoio multimídia de Geometria para me...

  9. Blower Cooling of Finned Cylinders

    Science.gov (United States)

    Schey, Oscar W; Ellerbrock, Herman H , Jr

    1937-01-01

    Several electrically heated finned steel cylinders enclosed in jackets were cooled by air from a blower. The effect of the air conditions and fin dimensions on the average surface heat-transfer coefficient q and the power required to force the air around the cylinders were determined. Tests were conducted at air velocities between the fins from 10 to 130 miles per hour and at specific weights of the air varying from 0.046 to 0.074 pound per cubic foot. The fin dimensions of the cylinders covered a range in pitches from 0.057 to 0.25 inch average fin thicknesses from 0.035 to 0.04 inch, and fin widths from 0.67 to 1.22 inches.

  10. Gas only nozzle

    Science.gov (United States)

    Bechtel, William Theodore; Fitts, David Orus; DeLeonardo, Guy Wayne

    2002-01-01

    A diffusion flame nozzle gas tip is provided to convert a dual fuel nozzle to a gas only nozzle. The nozzle tip diverts compressor discharge air from the passage feeding the diffusion nozzle air swirl vanes to a region vacated by removal of the dual fuel components, so that the diverted compressor discharge air can flow to and through effusion holes in the end cap plate of the nozzle tip. In a preferred embodiment, the nozzle gas tip defines a cavity for receiving the compressor discharge air from a peripheral passage of the nozzle for flow through the effusion openings defined in the end cap plate.

  11. Pulmonary function in commercial glass blowers.

    Science.gov (United States)

    Munn, N J; Thomas, S W; DeMesquita, S

    1990-10-01

    This study examined the pulmonary function of 87 male commercial glass factory workers. Statistical analysis of the data indicated that workers with full-time glass blowing job descriptions had significantly higher percent predicted values for FVC, FEV1 and significantly higher maximal inspiratory and expiratory muscle pressures than their cohorts with minimal or nonglass blowing job descriptions. The results of this study indicate that persons using their respiratory muscles as full-time blowers to manufacture commercial blown glass products have significantly greater lung function values than part-time blowers or their nonglass blowing co-workers.

  12. Ambiente hipermídia para o ensino da geometria

    OpenAIRE

    Macedo, Claudia Mara Scudelari de

    2004-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Programa de Pós-Graduação em Engenharia de Produção O ensino de geometria nos últimos anos tem se tornado uma tarefa cada vez mais difícil, tanto para os alunos como para os professores. Dentre os fatores que colaboraram para esta situação, destaca-se o despreparo dos professores neste conteúdo nos seus cursos de formação. Da mesma forma, as dificuldades encontradas pelos alunos no entendimento de temas mais avançados como o ...

  13. Observações sobre geometria sintética

    OpenAIRE

    Bassan, André Roberto [UNESP

    2015-01-01

    The objective of this work is to present some results of Euclidean geometry which are given in elementary and high school from the synthetic point of view, that is we will not assume the metric axioms. As an application we will make some constructions using the developed tools O objetivo deste trabalho é apresentar alguns resultados da Geometria Euclidiana no plano, que são vistos no ensino fundamental e médio sob ponto de vista sintético, ou seja, não serão assumidos os axiomas métricos. ...

  14. Accuracy of the blower door measurement; Genauigkeit der Blower Door-Messung. Der Einfluss von Aussenklimaparametern

    Energy Technology Data Exchange (ETDEWEB)

    Weier, H. [Hochschule fuer Technik, Wirtschaft und Sozialwesen Zittau/Goerlitz (FH), Zittau (Germany)

    2000-04-01

    The blower door is a simple to use measuring device for determing the seal of the external surfaces of buildings. The accuracy of the measurement is dependent to a considerable extent on the external climatic conditions that prevail at the time of taking the measurement. (orig.) [German] Die Blower Door ist ein einfach anzuwendendes Messgeraet zum Bestimmen der Dichtheit von Gebaeudeaussenflaechen. Die Genauigkeit der Messung ist in starkem Masse von den zum Messzeitpunkt herrschenden Aussenklimabedingungen abhaengig. (orig.)

  15. Production Facility Prototype Blower Installation Report

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dalmas, Dale Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-07-28

    The roots blower in use at ANL for in-beam experiments and also at LANL for flow tests was sized for 12 mm diameter disks and significantly less beam heating.  Currently, the disks are 29 mm in diameter, with a 12 mm FWHM Gaussian beam spot at 42 MeV and 2.86 μA on each side of the target, 5.72 μA total. The target design itself is reported elsewhere.  With the increased beam heating, the helium flow requirement increased so that a larger blower was need for a mass flow rate of 400 g/s at 2.76 MPa (400 psig).  An Aerzen GM 12.4 blower was selected, and is currently being installed at the LANL facility for target and component flow testing.  This report describes this blower/motor/ppressure vessel package and the status of the facility preparations.

  16. Cold spray nozzle design

    Science.gov (United States)

    Haynes, Jeffrey D.; Sanders, Stuart A.

    2009-06-09

    A nozzle for use in a cold spray technique is described. The nozzle has a passageway for spraying a powder material, the passageway having a converging section and a diverging section, and at least the diverging section being formed from polybenzimidazole. In one embodiment of the nozzle, the converging section is also formed from polybenzimidazole.

  17. Spiral cooled fuel nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Timothy; Schilp, Reinhard

    2012-09-25

    A fuel nozzle for delivery of fuel to a gas turbine engine. The fuel nozzle includes an outer nozzle wall and a center body located centrally within the nozzle wall. A gap is defined between an inner wall surface of the nozzle wall and an outer body surface of the center body for providing fuel flow in a longitudinal direction from an inlet end to an outlet end of the fuel nozzle. A turbulating feature is defined on at least one of the central body and the inner wall for causing at least a portion of the fuel flow in the gap to flow transverse to the longitudinal direction. The gap is effective to provide a substantially uniform temperature distribution along the nozzle wall in the circumferential direction.

  18. Production Facility Prototype Blower 1000 Hour Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dalmas, Dale Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-18

    The roots blower in use at ANL for in-beam experiments and also at LANL for flow tests was sized for 12 mm diameter disks and significantly less beam heating. Currently, the disks are 29 mm in diameter, with a 12 mm FWHM Gaussian beam spot at 42 MeV and 2.86 μA on each side of the target, 5.72 μA total. The target design itself is reported elsewhere. With the increased beam heating, the helium flow requirement increased so that a larger blower was needed for a mass flow rate of 400 g/s at 2.76 MPa (400 psig). An Aerzen GM 12.4 blower was selected, and is now installed at the LANL facility for target and component flow testing. Two extended tests of >1000 hr operation have been completed. Those results and discussion thereof are reported herein. Also included in Appendix A is the detailed description of the blower and its installation, while Appendix B documents the pressure vessel design analysis. The blower has been operated for 1000 hours as a preliminary investigation of long-term performance, operation and possible maintenance issues. The blower performed well, with no significant change in blower head or mass flow rate developed under the operating conditions. Upon inspection, some oil had leaked out of the shaft seal of the blower. The shaft seal and bearing race have been replaced. Test results and conclusions are in Appendix B.

  19. Production Facility Prototype Blower 1000 Hour Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dalmas, Dale Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-18

    The roots blower in use at ANL for in-beam experiments and also at LANL for flow tests was sized for 12 mm diameter disks and significantly less beam heating. Currently, the disks are 29 mm in diameter, with a 12 mm FWHM Gaussian beam spot at 42 MeV and 2.86 μA on each side of the target, 5.72 μA total. The target design itself is reported elsewhere. With the increased beam heating, the helium flow requirement increased so that a larger blower was need for a mass flow rate of 400 g/s at 2.76 MPa (400 psig). An Aerzen GM 12.4 blower was selected, and is now installed at the LANL facility for target and component flow testing. Two extended test of >1000 hr operation have been completed. Those results and discussion thereof are reported herein. Also included in Appendix A is the detailed description of the blower and its installation, while Appendix B documents the pressure vessel design analysis. The blower has been operated for 1000 hours as a preliminary investigation of long term performance, operation and possible maintenance issues. The blower performed well, with no significant change in blower head or mass flow rate developed under the operating conditions. Upon inspection, some oil had leaked out of the shaft seal of the blower. The shaft seal and bearing race have been replaced. Test results and conclusions are in Appendix B.

  20. Laboratory Evaluation of Residential Furnace BlowerPerformance

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain S.; Lutz, Jim D.

    2005-09-01

    A testing program was undertaken at Lawrence Berkeley National Laboratory and an electric utility (Pacific Gas and Electric Co.) to compare the performance of furnace blowers. This laboratory testing program was undertaken to support potential changes to California Building Standards regarding in-field furnace blower energy use. This technical support includes identifying suitable performance metrics and target performance levels for use in standards. Five different combinations of blowers and residential furnaces were tested for air moving performance. Three different types of blower and motor combinations were tested in two different furnace cabinets. The blowers were standard forward--curved impellors and a prototype impeller with reverse-inclined blades. The motors were two 6-pole permanent split capacitor (PSC) single-phase induction motors, a brushless permanent magnet (BPM) motor and a prototype BPM designed for use with a prototype reverse-inclined impellor. The laboratory testing operated each blower and furnace combination over a range of air flows and pressure differences to determine air flow performance, power consumption and efficiency. Additional tests varied the clearance between the blower housing and the furnace cabinet, and the routing of air flow into the blower cabinet.

  1. Vettath's blower and blower/mister - a simple device for OPCAB surgery.

    Science.gov (United States)

    Vettath, Murali P; Vellachamy, Kannan A; Talya, Rameshwara; Thazhakuni, Ismail; Moothencheri, Jayaprakash; Thomas, Jiji

    2008-01-01

    Since the advent of off-pump coronary artery bypass surgery, a blower/mister has been routinely used in cardiac operation theatres. In our setup, in an attempt to reduce the cost of coronary artery bypass grafting by performing off-pump coronary artery bypass, reusable materials have been routinely used.

  2. Blower door measurements - extended measuring methods; Blower Door-Messungen - erweiterte Messmethoden

    Energy Technology Data Exchange (ETDEWEB)

    Geissler, A.; Bolender, T.; Hauser, G. [Kassel Univ. (Germany). Fachgebiet Bauphysik

    1997-05-01

    To determine the air tightness of the external envelope, blower door measurements are normally carried out. The thus determined integral figure for the complete structure is an insufficient basis for carrying out specific insulation procedures in existing buildings. Within the scope of the air tightness measurements with the blower door, additional measuring methods permit the determination of additional information on the leakage distribution and the leakage routes. The expanded measuring methods that are known from the bibliography `opening a door` and `adding a hole` as well as the new method of `adding a hole plus` are explained, compared by means of exemplary measurements, and are considered for their suitability during field trials. (orig.) [Deutsch] Zur Bestimmung der Luftdichtheit der Gebaeudehuelle werden im allgemeinen Blower Door-Messungen durchgefuehrt. Der hierbei bestimmte integrale Wert fuer das gesamte Gebaeude stellt fuer das Ergreifen von gezielten Abdichtungsmassnahmen im Gebaeudebestand eine zu geringe Basis dar. Weiterfuehrende Messmethoden erlauben, im Rahmen von Luftdichtheitsmessungen mit der Blower Door zusaetzliche Informationen ueber die Leckageverteilung und ueber Leckagewege zu bestimmen. Die aus der Literatur bekannten erweiterten Messmethoden `Opening A Door` und `Adding A Hole` sowie die neue Methode `Adding A Hole Plus` werden erlaeutert, anhand von exemplarischen Messungen verglichen und im Feldeinsatz auf ihre Anwendbarkeit hin betrachtet. (orig.)

  3. Recent Results on High-Pressure Axial Blowers

    Science.gov (United States)

    Eckert, B.

    1947-01-01

    Considerable progress has, in recent times, been attained in the development of the high-pressure axial blower by well-planned research. The efforts are directed toward improving the efficiencies, which are already high for the axial blower, and in particular the delivery pressure heads. For high pressures multistage arrangements are used. Of fundamental importance is the careful design of all structural parts of the blower that are subject to the effects of the flow. In the present report, several recent results and experiences are reported, which are based on results of German engine research.

  4. Gas only nozzle fuel tip

    Energy Technology Data Exchange (ETDEWEB)

    Bechtel, William Theodore (Scotia, NY); Fitts, David Orus (Ballston Spa, NY); DeLeonardo, Guy Wayne (Glenville, NY)

    2002-01-01

    A diffusion flame nozzle gas tip is provided to convert a dual fuel nozzle to a gas only nozzle. The nozzle tip diverts compressor discharge air from the passage feeding the diffusion nozzle air swirl vanes to a region vacated by removal of the dual fuel components, so that the diverted compressor discharge air can flow to and through effusion holes in the end cap plate of the nozzle tip. In a preferred embodiment, the nozzle gas tip defines a cavity for receiving the compressor discharge air from a peripheral passage of the nozzle for flow through the effusion openings defined in the end cap plate.

  5. Burner blower technology: Adjustable blower with minimum loss and noise; Brennergeblaesetechnik: Regelbares Brennergeblaese mit minimalen Verlusten und Geraeuschen

    Energy Technology Data Exchange (ETDEWEB)

    Kanis, P.G.

    1999-11-01

    The problem of blower control was mentioned in an earlier issue (Waermetechnik 1993, No. 5/6). This contribution presents a novel blower which enables practically loss-free adaptation of the air volume flow and thus helps to save electrical energy and minimize blower noise. [German] In der Waermetechnik 1993, Heft 5 und 6, wurden die Grundlagen der Brennergeblaesetechnik zusammengefasst und dabei auch die Problematik der Geblaeseregelung angesprochen. Im heutigen Beitrag soll ein neues Brennergeblaese vorgestellt werden, welches eine nahezu verlustfreie Anpassung des Luftvolumenstroms an den jeweiligen Bedarf ermoeglicht und dadurch hilft, elektrische Energie einzusparen und die Geblaesegeraeusche zu minimieren. (orig.)

  6. Optimization of repair cycles of VOMD-24 blowers

    Energy Technology Data Exchange (ETDEWEB)

    Kosarev, N.P.; Kuznetsov, S.V. (Sverdlovskii Gornyi Institut (USSR))

    1990-04-01

    Evaluates service life, reliability and repair of VOMD-24 blowers used for ventilation in underground coal mines in the USSR. Depending on operational conditions and ventilation systems, the overhaul life ranges from 7.2 to 14.7 months or 17.7 and 22.5 months (if general overhauls are considered). The mean-time-to repair ranges from 23.3 to 24.0 months, mean-time-to general overhaul from 32.6 to 38.0 months. The average labor consumption of blower repair and of general overhauls is analyzed along with labor consumption of service operations and repair. The recommended and actual standard repair cost, labor consumption and repair intervals are comparatively evaluated. Mathematical models for optimization of repair intervals are evaluated. Use of mathematical modeling for reducing repair cost, increasing blower reliability and reducing losses caused by blower failures is analyzed. 4 refs.

  7. EC motors for blowers; EC-Motoren fuer Luefter

    Energy Technology Data Exchange (ETDEWEB)

    Sauer, Thomas; Reiff, Ellen-Christine

    2009-10-15

    There are highly flexible commercial ventilation and air conditioning systems for server rooms which combine energy savings with optimum room air quality. EC blowers contribute to this and reduce also body sound. (orig./GL)

  8. Soot blower using fuel gas as blowing medium

    Science.gov (United States)

    Tanca, Michael C.

    1982-01-01

    A soot blower assembly (10) for use in combination with a coal gasifier (14). The soot blower assembly is adapted for use in the hot combustible product gas generated in the gasifier as the blowing medium. The soot blower lance (20) and the drive means (30) by which it is moved into and out of the gasifier is housed in a gas tight enclosure (40) which completely surrounds the combination. The interior of the enclosure (40) is pressurized by an inert gas to a pressure level higher than that present in the gasifier so that any combustible product gas leaking from the soot blower lance (20) is forced into the gasifier rather than accumulating within the enclosure.

  9. Vibration and Stability of 3000-hp, Titanium Chemical Process Blower

    Directory of Open Access Journals (Sweden)

    Les Gutzwiller

    2003-01-01

    Full Text Available This 74-in-diameter blower had an overhung rotor design of titanium construction, operating at 50 pounds per square inch gauge in a critical chemical plant process. The shaft was supported by oil-film bearings and was directdriven by a 3000-hp electric motor through a metal disk type of coupling. The operating speed was 1780 rpm. The blower shaft and motor shaft motion was monitored by Bently Nevada proximity probes and a Model 3100 monitoring system.

  10. Optimization of axial blowers. Optimierung von Axial-Ventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Bolte, W.

    1992-08-01

    For the optimum possible design of axial blowers, trials are evaluated in the article, which are based on the grid profile examined by N. Scholz. The computation for the pressure number and the primary degree of efficiency are shown as well as the evaluation of the effect of the Reynolds and mach number on the degree of efficiency and determination of the secondary losses. In a final example, the dimensions of a blower are computed from the data determined during the trials. (orig.).

  11. Integrated high efficiency blower apparatus for HVAC systems

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaoyue; Weigman, Herman; Wang, Shixiao

    2007-07-24

    An integrated centrifugal blower wheel for a heating, ventilation and air conditioning (HVAC) blower unit includes a first blade support, a second blade support, and a plurality of S-shaped blades disposed between the first and second blade supports, wherein each of the S-shaped blades has a trailing edge bent in a forward direction with respect to a defined direction of rotation of the wheel.

  12. Dynamical system analysis of unstable flow phenomena in centrifugal blower

    Directory of Open Access Journals (Sweden)

    Garcia David

    2015-09-01

    Full Text Available Methods of dynamical system analysis were employed to analyze unsteady phenomena in a centrifugal blower. Pressure signals gathered at different control points were decomposed into their Principal Components (PCs by means of Singular Spectrum Analysis (SSA. Certain number of PCs was considered in the analysis based on their statistical correlation. Projection of the original signal onto its PCs allowed to draw the phase trajectory that clearly separated non-stable blower working conditions from its regular operation.

  13. TEORIA E APLICAÇÃO DA GEOMETRIA HIDRÁULICA: REVISÃO

    Directory of Open Access Journals (Sweden)

    Fernando Grison

    2011-12-01

    Full Text Available Desde a criação da teoria da geometria hidráulica, um elevado número de trabalhos foi desenvolvido em relação a essa teoria e sua aplicação. O presente estudo teve o objetivo de revisar a definição dessa teoria, formas pelas quais ela vem sendo estudada e os principais métodos aplicados para interpretação dos seus resultados. As principais descobertas mostram que, com aumento da vazão, a velocidade e a profundidade aumentam mais rapidamente do que a largura das seções transversais e que a variação da largura nos canais com leito rochoso é semelhante àquela com leito aluvial. Foi claramente observado que as relações matemáticas da geometria hidráulica, que se diferenciam pela mudança da potência do escoamento do curso d’água, vêm sendo detalhadamente estudadas. Vários tipos de clima e formações geológicas foram avaliados para verificar suas influências nos expoentes da geometria hidráulica. Além disso, também se investigou o motivo das grandes variações dos valores desses expoentes. A vazão dominante está intimamente correlacionada com a área de drenagem e, a partir disso, foram desenvolvidas as Equações Regionais da Geometria Hidráulica. Outros trabalhos mostraram o comportamento dos sedimentos com relação às mudanças na forma dos cursos d’água. O tópico mais explorado na geometria hidráulica é a modelagem matemática, que foi utilizada principalmente para investigar a influência da forma de uma seção transversal e do leito de um canal em nível de margens plenas no comportamento das variáveis hidráulicas. A modelagem matemática também foi empregada para verificar a variabilidade espacial da geometria hidráulica devido à localização das seções transversais. As aplicações da geometria hidráulica encontram-se, na prática, tal como em projetos de revitalizações de rios e projetos de gerenciamento de recursos hídricos.

  14. Transition nozzle combustion system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Won-Wook; McMahan, Kevin Weston; Maldonado, Jaime Javier

    2016-11-29

    The present application provides a combustion system for use with a cooling flow. The combustion system may include a head end, an aft end, a transition nozzle extending from the head end to the aft end, and an impingement sleeve surrounding the transition nozzle. The impingement sleeve may define a first cavity in communication with the head end for a first portion of the cooling flow and a second cavity in communication with the aft end for a second portion of the cooling flow. The transition nozzle may include a number of cooling holes thereon in communication with the second portion of the cooling flow.

  15. Wear characterization of abrasive waterjet nozzles and nozzle materials

    Science.gov (United States)

    Nanduri, Madhusarathi

    Parameters that influence nozzle wear in the abrasive water jet (AWJ) environment were identified and classified into nozzle geometric, AWJ system, and nozzle material categories. Regular and accelerated wear test procedures were developed to study nozzle wear under actual and simulated conditions, respectively. Long term tests, using garnet abrasive, were conducted to validate the accelerated test procedure. In addition to exit diameter growth, two new measures of wear, nozzle weight loss and nozzle bore profiles were shown to be invaluable in characterizing and explaining the phenomena of nozzle wear. By conducting nozzle wear tests, the effects of nozzle geometric, and AWJ system parameters on nozzle wear were systematically investigated. An empirical model was developed for nozzle weight loss rate. To understand the response of nozzle materials under varying AWJ system conditions, erosion tests were conducted on samples of typical nozzle materials. The effect of factors such as jet impingement angle, abrasive type, abrasive size, abrasive flow rate, water pressure, traverse speed, and target material was evaluated. Scanning electron microscopy was performed on eroded samples as well as worn nozzles to understand the wear mechanisms. The dominant wear mechanism observed was grain pullout. Erosion models were reviewed and along the lines of classical erosion theories a semi-empirical model, suitable for erosion of nozzle materials under AWJ impact, was developed. The erosion data correlated very well with the developed model. Finally, the cutting efficiency of AWJ nozzles was investigated in conjunction with nozzle wear. The cutting efficiency of a nozzle deteriorates as it wears. There is a direct correlation between nozzle wear and cutting efficiency. The operating conditions that produce the most efficient jets also cause the most wear in the nozzle.

  16. MEMS-Based Spinning Nozzle

    Science.gov (United States)

    Okojie, Robert S. (Inventor)

    2003-01-01

    A nozzle body and assembly for delivering atomized fuel to a combustion chamber. The nozzle body is rotatably mounted onto a substrate. One or more curvilinear fuel delivery channels are in flow communication with an internal fuel distribution cavity formed in the nozzle body. Passage of pressurized fuel through the nozzle body causes the nozzle body to rotate. Components of the nozzle assembly are formed of silicon carbide having surfaces etched by deep reactive ion etching utilizing MEMS (micro-electro-mechanical systems) technology. A fuel premix chamber is carried on the substrate in flow communication with a supply passage in the nozzle body.

  17. Furnace Blower Electricity: National and Regional Savings Potential

    Energy Technology Data Exchange (ETDEWEB)

    Florida Solar Energy Center; Franco, Victor; Franco, Victor; Lutz, Jim; Lekov, Alex; Gu, Lixing

    2008-05-16

    Currently, total electricity consumption of furnaces is unregulated, tested at laboratory conditions using the DOE test procedure, and is reported in the GAMA directory as varying from 76 kWh/year to 1,953 kWh/year. Furnace blowers account for about 80percent of the total furnace electricity consumption and are primarily used to distribute warm air throughout the home during furnace operation as well as distribute cold air during air conditioning operation. Yet the furnace test procedure does not provide a means to calculate the electricity consumption during cooling operation or standby, which account for a large fraction of the total electricity consumption. Furthermore, blower electricity consumption is strongly affected by static pressure. Field data shows that static pressure in the house distribution ducts varies widely and that the static pressure used in the test procedure as well as the calculated fan power is not representative of actual field installations. Therefore, accurate determination of the blower electricity consumption is important to address electricity consumption of furnaces and air conditioners. This paper compares the potential regional and national energy savings of two-stage brushless permanent magnet (BPM) blower motors (the blower design option with the most potential savings that is currently available in the market) to single-stage permanent split capacitor (PSC) blower motors (the most common blower design option). Computer models were used to generate the heating and cooling loads for typical homes in 16 different climates which represent houses throughout the United States. The results show that the potential savings of using BPM motors vary by region and house characteristics, and are very strongly tied to improving house distribution ducts. Savings decrease dramatically with increased duct pressure. Cold climate locations will see savings even in the high static pressure duct situations, while warm climate locations will see less

  18. Optimized inflow in radial blowers. Efficient blowers; Optimaler Radeinlauf von Radialventilatoren. Effiziente Ventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Siepert, Heinz [VENTAPP GmbH und CO. KG, Kempen (Germany)

    2002-05-01

    It is well known that the inflow configuration of radial blowers influences the filling level of the rotor wheel and the rotor blade flow loss significantly. The author shows how losses can be minimized, thus improving the hydraulic efficiency. [German] Schon lange ist bekannt, dass die gewaehlte Radeinlaufkonfiguration bei Radialventilatoren einen grossen Einfluss auf den Fuellungsgrad des Laufrades und somit auch auf die Verluste der Laufschaufelstroemung hat. In der vorliegenden Arbeit wird gezeigt, wie die hydraulischen Radverluste aufgrund dieses Sachverhaltes minimiert und dadurch auch der hydraulische Wirkungsgrad verbessert werden koennen. (orig.)

  19. La geometria del còdex 80 (s. XII de la catedral de Tortosa

    Directory of Open Access Journals (Sweden)

    Lluís i Ginovart, Josep

    2015-12-01

    Full Text Available The geometry in codex 80 of the Capitular Archive has traditionally been understood as a complete text and attributed to Gerbert of Aurillac (c. 940-1003. From a new reading of the text, we can say that it is a miscellaneous writing about geometry, composed of three independent parts: one containing the Geometria Incerti Auctoris apocryphical by Gerbert of Aurillac (c. 940-1003; another one is a fragment of De Nuptiis Philologiae et Mercurii by Martianus Capella (fl . 430 from Ergasticis Schematibus of Book VII of the Geometry; and finally there is a gloss to the Elementa by Euclides (c. 325-c. 265 bC. by Al-Ḥajjāj ibn Yūsuf ibn Maṭar (786-833. The interpretation of the geometrical propositions provides knowledge about the indirect measure of places which are inaccessible using medieval instrumental, the astrolabe, mirrors, cane and squares.[ct] La geometria del còdex 80 de l’Arxiu Capitular de Tortosa ha estat tradicionalment atribuïda, com un text únic, a Gerbert d’Orlhac (c. 940-1003. Una nova lectura del text ens permet assegurar que es tracta d’un text de caràcter miscel·lani de geometria, compost per tres textos independents: una part pertany a la Geometria Incerti Auctoris apòcrifa de Gerbert d’Orlhac; una altra, al fragment De Nuptiis Philologiae et Mercurii de Marcià Capella (fl . 430 Ergasticis Schematibus, del llibre VII de la Geometria; i, finalment, s’hi llegeix una glossa als Elementa d’Euclides (c. 325-c. 265 aC. d’Al-Ḥajjāj ibn Yūsuf ibn Maṭar (786-833. La interpretació de les proposicions de la geometria dóna el coneixement de la mesura indirecta de llocs als quals no es pot accedir amb l’instrumental medieval, és a dir, amb astrolabi, miralls, bastons i escaires.

  20. Noise analysis of ring blowers; Ring blow no soon kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Ota, S.; Miyazawa, M. [Fuji Electric Co. Ltd., Tokyo (Japan)

    1996-11-10

    The Ring Blower (a commercial product name of a vortex flow blower developed and marketed by Fuji Electric) consists integratedly of a blower, a motor and a silencer. The blower has an impeller attached with 40 to 52 forward-inclined blades, and is small in size capable of outputting high wind pressure. This paper describes the noise analyzing technology used in developing the low-noise Ring Blower, mainly referring to practical applications. A spectral analysis revealed that the noise is composed of rotor blade rotation noise forming several peaks and turbulent noise showing gently-sloping distribution over a wide range of frequency band. Vibration of outer walls of a casing would generate noise which propagates as a sound wave. For such vibration noise as this noise which spreads out into endless space, a BEM analysis is an effective tool. For analyzing flows to optimize blade shapes and analyzing sound pressure distribution in a silencer, an FEM analysis is effective. As a result of applying these technologies, noise has been reduced by over 10 dB from that in conventional products. 2 refs., 12 figs.

  1. 46 CFR 154.1868 - Portable blowers in personnel access openings.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Portable blowers in personnel access openings. 154.1868 Section 154.1868 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS... Portable blowers in personnel access openings. The master shall ensure that a portable blower in...

  2. 42 CFR 84.144 - Hand-operated blower test; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Hand-operated blower test; minimum requirements. 84... Supplied-Air Respirators § 84.144 Hand-operated blower test; minimum requirements. (a) Hand-operated blowers shall be tested by attaching them to a mechanical drive and operating them 6 to 8 hours daily...

  3. Building America Top Innovations 2013 Profile – High-Performance Furnace Blowers

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2013-09-01

    This Top Innovations profile describes Lawrence Berkeley National Laboratory's work with furnace blower design that led to the creation of a standard for rating blowers, credits for the use of good blowers in Federal tax credit programs and energy codes, and consideration in current federal rulemaking procedures.

  4. 42 CFR 84.145 - Motor-operated blower test; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Motor-operated blower test; minimum requirements... Supplied-Air Respirators § 84.145 Motor-operated blower test; minimum requirements. (a) Motor-operated... connection between the motor and the blower shall be so constructed that the motor may be disengaged from...

  5. Architettura e/è Geometria: dalla forma architettonica alla costruzione geometrica

    Directory of Open Access Journals (Sweden)

    Mariateresa Galizia

    2012-06-01

    Full Text Available L’avvento delle tecnologie digitali di acquisizione dati 3D ha proiettato gli studiosi dell’architettura in una dimensione del tutto inaspettata. Milioni di punti hanno travolto ricercatori e professionisti ancora culturalmente impreparati ad affrontare la rivoluzione digitale nel campo del Rilievo. Le nuvole di punti acquisite documentano e allo stesso tempo rappresentano la spazialità degli oggetti reali, tuttavia, nulla rivelano su forma e geometria, architettura e materia se non attraverso una successiva interpretazione. Il contributo vuole soffermarsi sulle implicazioni teoriche e applicative del processo di interpretazione dei dati acquisiti per la comprensione della geometria e sulla funzione euristica della modellazione digitale, nel passaggio dal “noto all’ignoto”, nella “ri-scoperta” della forma e quindi dell’idea progettuale.

  6. La geometria delle volte medievali e la percezione spaziale dell’architetto

    Directory of Open Access Journals (Sweden)

    Emiliano Della Bella

    2012-06-01

    Full Text Available La geometria intesa nelle sue accezioni più ampie ha accompagnato la figura dell’architetto e dell’erudito fin dai tempi più remoti. Una serie di disegni muti aventi per soggetto le volte a stella, raccolti nel Libretto di Dresda (1544-1567 dimostra il grande valore attribuito alla geometria da parte dei mason medievali. Velata anche da numerosi risvolti mistici, la conoscenza geometrica è tramanda da maestro a novizio nel più profondo riserbo. I disegni del Libretto, muti ai più, si esprimono con chiarezza cristallina a coloro che ne comprendono le meccaniche spaziali. Il ritrovamento di uno dei disegni originali di Marcello Piacentini per la cupola della Casa Madre dei Mutilati ed Invalidi di Guerra in Roma (1925-1928 può dimostrare come il ‘metodo di Dresda’ fosse ancora bagaglio culturale dell’architetto del XX secolo.

  7. Nozzle fabrication technique

    Science.gov (United States)

    Wells, Dennis L. (Inventor)

    1988-01-01

    This invention relates to techniques for fabricating hour glass throat or convergent divergent nozzle shapes, and more particularly to new and improved techniques for forming rocket nozzles from electrically conductive material and forming cooling channels in the wall thereof. The concept of positioning a block of electrically conductive material so that its axis is set at a predetermined skew angle with relation to a travelling electron discharge machine electrode and thereafter revolving the body about its own axis to generate a hyperbolic surface of revolution, either internal or external is novel. The method will generate a rocket nozzle which may be provided with cooling channels using the same control and positioning system. The configuration of the cooling channels so produced are unique and novel. Also the method is adaptable to nonmetallic material using analogous cutting tools, such as, water jet, laser, abrasive wire and hot wire.

  8. Ensino de Geometria Espacial métrica: uma experiência com modelagem

    Directory of Open Access Journals (Sweden)

    Andrea Cardoso

    2012-12-01

    Full Text Available O estudo de geometria permite o desenvolvimento de habilidades e conhecimentos em relação a fatos e questões do cotidiano. Entretanto, os resultados em exames oficiais apontam uma grande defasagem no ensino e aprendizagem, principalmente em geometria espacial. Esta pesquisa está inserida no contexto do ensino e aprendizagem da geometria espacial na educação básica, em particular, à métrica dos sólidos geométricos. O objetivo do trabalho é apresentar uma sequência didática utilizando a modelagem matemática como alternativa metodológica, tendo em vista seu potencial para quebrar a dicotomia existente entre a matemática escolar e a matemática presente nas mais variadas situações do cotidiano. A sequência foi desenvolvida em duas escolas públicas junto a estudantes do ensino médio. Para validar a sequência proposta, a pesquisa foi fundamentada nos princípios da engenharia didática e a análise foi realizada utilizando-se registros em diário de campo, registros das atividades desenvolvidas pelos estudantes e aplicação de questionários e testes diagnósticos. Os resultados obtidos levaram a concluir que houve um avanço por parte dos estudantes na apreensão de conceitos de geometria plana e espacial.

  9. Performance of Air-cooled Engine Cylinders Using Blower Cooling

    Science.gov (United States)

    Schey, Oscar W; Ellerbrock, Herman H , Jr

    1936-01-01

    An investigation was made to obtain information on the minimum quantity of air and power required to cool conventional air cooled cylinders at various operating conditions when using a blower. The results of these tests show that the minimum power required for satisfactory cooling with an overall blower efficiency of 100 percent varied from 2 to 6 percent of the engine power depending on the operating conditions. The shape of the jacket had a large effect on the cylinder temperatures. Increasing the air speed over the front of the cylinder by keeping the greater part of the circumference of the cylinder covered by the jacket reduced the temperatures over the entire cylinder.

  10. The seismic design of axial blower using Ansys

    Energy Technology Data Exchange (ETDEWEB)

    Im, Hyung Bin; Kim, Kang Sung; Heo, Jin Wook; Chung, Jin Tai [Hanyang Univ., Seoul (Korea, Republic of)

    2001-07-01

    The seismic design for an axial blower is the procedure in which the Required Response Spectrum(RRS) is computed by using the Floor Response Spectrum(FRS). The seismic design is very important to reduce severe damages from an earthquake; therefore, the seismic design has been a great concern in engineering society. In this study, after finite element modeling is established by using Ansys, the modal data are obtained such as the natural frequencies, the participation factor, and so on. With these data, the RRS is acquired by a numerical approach. The seismic safety of the axial blower is evaluated.

  11. Performance characteristics of turbo blower in a refuse collecting system according to operation conditions

    Energy Technology Data Exchange (ETDEWEB)

    Jang, C. M.; Kim, D. W. [Korea Institute of Construction Technology, Goyang (Korea, Republic of); Lee, S. Y. [ANST, Seoul (Korea, Republic of)

    2008-10-15

    A simulator for a refuse collecting system is designed to investigate the performance characteristics of a turbo blower operating at different rotational frequencies. The simulator consists of an air intake, a waste chute, circular duct, waste collector and turbo blower. Experimental measurements and numerical simulation with three-dimensional Navier- Stokes equations have been performed to analyze the performance of the turbo blower. Throughout numerical simulation of the simulator, it is found that the input energy of the blower can be reduced by controlling the rotational frequency of impeller while the efficiency of the blower keeps constant. The required outlet pressure and flow rate of the blower can be also adjusted along the system resistance of the refuse collecting system. Detailed flow characteristics inside the blower are analyzed for different rotational frequencies

  12. O ensino de geometria, em escolas públicas, na cidade de Jequié - Bahia

    Directory of Open Access Journals (Sweden)

    Jamille Santana Gonçalves

    2012-12-01

    Full Text Available Neste trabalho nos propomos a analisar a atual situação do ensino de Geometria na 5ª série do Ensino Fundamental de algumas escolas públicas da cidade de Jequié-Bahia. Os objetivos da pesquisa foram verificar se a Geometria está sendo ensinada; perceber, em relação aos professores que a ensinam, como este ensino é realizado e quais as metodologias adotadas; e, investigar, em relação aos professores que não ensinam Geometria, quais os motivos que os levam a não ensiná-la. Para desenvolver este trabalho, teoricamente, recorremos a autores como: Regina Maria Pavanello, Adair Mendes Nacarato e  Cármen Lúcia Brancaglion Passos,  Geraldo Perez, entre outros. Utilizamos a abordagem metodológica qualitativa, através do estudo de caso e a coleta de dados se deu por meio de um questionário aplicado a oito professores da rede pública, sendo cinco da rede municipal e três da rede estadual. Os dados foram analisados mediante o método da análise de conteúdo. De posse dos dados e sua estruturação pudemos perceber que o ensino de Geometria nas escolas pesquisadas é ainda quase ausente e alguns dos fatores que pudemos constatar para justificar essa situação é o fato de ainda existirem professores de outras áreas ensinando matemática, a falta de conhecimentos geométricos, mesmo dos professores da área e o descaso das secretarias de educação no que diz respeito à capacitação dos professores.Palavras-chave: matemática; educação matemática; ensino de geometria; capacitação de professores.

  13. The TICTOP nozzle: a new nozzle contouring concept

    Science.gov (United States)

    Frey, Manuel; Makowka, Konrad; Aichner, Thomas

    2016-10-01

    Currently, mainly two types of nozzle contouring methods are applied in space propulsion: the truncated ideal contour (TIC) and the thrust-optimized parabola (TOP). This article presents a new nozzle contouring method called TICTOP, combining elements of TIC and TOP design. The resulting nozzle is shock-free as the TIC and therefore does not induce restricted shock separation leading to excessive side-loads. Simultaneously, the TICTOP nozzle will allow higher nozzle wall exit pressures and hence give a better separation margin than is the case for a TIC. Hence, this new nozzle type combines the good properties of TIC and TOP nozzles and eliminates their drawbacks. It is especially suited for first stage application in launchers where flow separation and side-loads are design drivers.

  14. Que geometria ensinar? uma breve história da redefinição do conhecimento elementar matemático para crianças

    Directory of Open Access Journals (Sweden)

    Wagner Rodrigues Valente

    2013-04-01

    Full Text Available O artigo aborda a geometria para crianças, seu ensino para alunos das primeiras séries escolares. Leva em conta, inicialmente, a trajetória da Geometria para o nível elementar, desde, praticamente, a Independência do Brasil. Nessa análise, evidencia a permanência de conteúdos da geometria euclidiana até quase meados do século XX. Em seguida, analisa as propostas de alteração do ensino de Geometria elaboradas na década de 1960. Com isso, procura mostrar as intenções de modificar os conteúdos desse ramo matemático, em busca da redefinição de um novo elementar: um novo conhecimento elementar de geometria, vindo de processos de apropriação das contribuições trazidas pelos estudos da Psicologia cognitiva.

  15. Energy conservation in cooling systems. Blowers; Energiebesparing in koelsystemen. Ventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Huijgens, G.

    2009-03-15

    On the role of blowers with regard to the options to save energy with cooling systems. In particular attention is paid to so-called Electronically Commutated (EC) Motors. [Dutch] Over de rol van ventilatoren in de mogelijkheden om energie te besparen met koelsystemen. In het bijzonder wordt aandacht besteed aan de zogenaamde Electronically Commutated (EC) Motors.

  16. Blower-door techniques for measuring interzonal leakage

    Energy Technology Data Exchange (ETDEWEB)

    Hult, Erin L.; Sherman, Max H.; Walker, Iain

    2013-01-01

    Abstract The standard blower door test methods, such as ASTM E779, describe how to use a single blower door to determine the total leakage of a single-zone structure such as a detached single-family home. There are no standard test methods for measuring interzonal leakage in a two-zone or multi-zone building envelope such as might be encountered in with an attached garage or in a multifamily building. Some practitioners have been using techniques that involve making multiple measurements with a single blower door as well as combined measurements using multiple blower doors. Even for just two zones there are dozens of combinations of one-door and two-door test protocols that could conceivably be used to determine the interzonal air tightness. We examined many of these two-zone configurations using both simulation and measured data to estimate the accuracy and precision of each technique for realistic measurement scenarios. We also considered the impact of taking measurements at a single pressure versus over multiple pressures. We compared the various techniques and evaluated them for specific uses. Some techniques work better in one leakage regime; some are more sensitive to wind and other noise; some are more suited to determining only a subset of the leakage values. This paper makes recommendations on which techniques to use or not use for various cases and provides data that could be used to develop future test methods.

  17. Geometria na educação infantil: da manipulação empirista ao concreto piagetiano

    OpenAIRE

    Simone de Souza; Valdeni Soliani Franco

    2012-01-01

    Refletir sobre os conhecimentos de geometria do professor de educação infantil e as concepções epistemológicas que fundamentam suas condutas pedagógicas foi o objetivo de nossa pesquisa. A análise dos discursos indicou boa vontade das professoras para o trabalho geométrico, entretanto o desconhecimento da geometria enquanto teoria e a enraizada concepção epistemológica empirista, reportaram à ideia de que este conhecimento está nos objetos, bastando sua manipulação para que haja aprendizagem....

  18. A influência do origami no processo ensino-aprendizagem da geometria do 9º ano - ensino fundamental

    OpenAIRE

    Silva, Marcondes Sabóia

    2014-01-01

    O objetivo principal desse trabalho é analisar o quanto a técnica do Origami influencia no processo ensino-aprendizagem da Geometria Euclidiana no Ensino Fundamental, em particular no 9º ano. Para isso foram elaborados um questionário para professores e uma avaliação diagnóstica para os alunos do 9º ano com conceitos básicos de Geometria, referentes a séries anteriores. Foi feita uma experiência em sala de aula, na qual cinco turmas do 9º ano foram divididas em dois grupos. Um dos grupos estu...

  19. Numerical Simulations of Canted Nozzle and Scarfed Nozzle Flow Fields

    Science.gov (United States)

    Javed, Afroz; Chakraborty, Debasis

    2016-06-01

    Computational fluid dynamics (CFD) techniques are used for the analysis of issues concerning non-conventional (canted and scarfed) nozzle flow fields. Numerical simulations are carried out for the quality of flow in terms of axisymmetric nature at the inlet of canted nozzles of a rocket motor. Two different nozzle geometries are examined. The analysis of these simulation results shows that the flow field at the entry of the nozzles is non axisymmetric at the start of the motor. With time this asymmetry diminishes, also the flow becomes symmetric before the nozzle throat, indicating no misalignment of thrust vector with the nozzle axis. The qualitative flow fields at the inlet of the nozzles are used in selecting the geometry with lesser flow asymmetry. Further CFD methodology is used to analyse flow field of a scarfed nozzle for the evaluation of thrust developed and its direction. This work demonstrates the capability of the CFD based methods for the nozzle analysis problems which were earlier solved only approximately by making simplifying assumptions and semi empirical methods.

  20. Problemas de medida e geometria: resoluções alternativas e variantes sem palavras

    OpenAIRE

    Ferreira, Maria da Conceição Gonçalves Martinho

    2015-01-01

    Nesta dissertação, incluem-se vários problemas de Matemática, envolvendo conteúdos de Geometria e Medida, dirigidos a estudantes do Ensino Básico e Secundário. A ideia orientadora é a seguinte: o uso de “provas sem palavras” em sala de aula pode contribuir para induzir nos alunos uma melhor compreensão de conceitos, relações, teoremas e demonstrações, por estes serem apresentados de um modo visual. Propomos uma aplicação mais frequente desta ferramenta pedagógica, uma vez qu...

  1. Design and Development of a Regenerative Blower for EVA Suit Ventilation

    Science.gov (United States)

    Izenson, Michael G.; Chen, Weibo; Hill, Roger W.; Phillips, Scott D.; Paul, Heather L.

    2011-01-01

    Ventilation subsystems in future space suits require a dedicated ventilation fan. The unique requirements for the ventilation fan - including stringent safety requirements and the ability to increase output to operate in buddy mode - combine to make a regenerative blower an attractive choice. This paper describes progress in the design, development, and testing of a regenerative blower designed to meet requirements for ventilation subsystems in future space suits. We have developed analysis methods for the blower s complex, internal flows and identified impeller geometries that enable significant improvements in blower efficiency. We verified these predictions by test, measuring aerodynamic efficiencies of 45% at operating conditions that correspond to the ventilation fan s design point. We have developed a compact motor/controller to drive the blower efficiently at low rotating speed (4500 rpm). Finally, we have assembled a low-pressure oxygen test loop to demonstrate the blower s reliability under prototypical conditions.

  2. Design and Development of a Regenerative Blower for Space Suit Ventilation

    Science.gov (United States)

    Izenson, Mike; Chen, Weibo; Paul, Heather

    2010-01-01

    The ventilation subsystem in future space suits will require a dedicated ventilation fan. The unique requirements for the ventilation fan, including stringent safety requirements and the ability to increase output to operate in buddy mode, combine to make a regenerative blower an attractive technology choice. This paper describes progress in the design, development, and testing of a regenerative blower designed to meet requirements for a ventilation subsystem for future space suit life support. Analysis methods were developed for the blower s complex internal flows and impeller geometries were identified that enable significant improvements in blower efficiency. Performance predictions were verified by test, measuring aerodynamic efficiencies of 45% at operating conditions that correspond to the ventilation fan s design point. A compact motor/controller was developed to drive the blower efficiently at low rotating speed (4500 rpm). Finally, a low-pressure oxygen test loop was assembled to demonstrate the blower s reliability under prototypical conditions.

  3. Performance Enhancement of Dual-Inlet Centrifugal Blower by Optimal Design of Splitter

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Sung; Jang, Choon Man [Korea Institute of Construction Technology, Goyang (Korea, Republic of)

    2014-12-15

    The shape of an impeller splitter for a dual-inlet centrifugal blower was optimized to enhance the blower performance. Two design variable, the normalized chord and pitch of a splitter, were used to evaluate the blower performance and internal flow fields based on the three-dimensional flow analysis. The blower performance obtained using this numerical simulation had a maximum error of 4 percent compared to that in an experiment at the design flow condition. The shape optimization of the splitter successfully increased the blower efficiency and pressure by 3.65 and 1.14 percent compared to the reference values. The blower performance was increased by reducing the flow separation near the blade suction surface by optimizing the shape of the splitter, which produced a pressure increase at the outlet of the volute casing.

  4. Fuel nozzle tube retention

    Energy Technology Data Exchange (ETDEWEB)

    Cihlar, David William; Melton, Patrick Benedict

    2017-02-28

    A system for retaining a fuel nozzle premix tube includes a retention plate and a premix tube which extends downstream from an outlet of a premix passage defined along an aft side of a fuel plenum body. The premix tube includes an inlet end and a spring support feature which is disposed proximate to the inlet end. The premix tube extends through the retention plate. The spring retention feature is disposed between an aft side of the fuel plenum and the retention plate. The system further includes a spring which extends between the spring retention feature and the retention plate.

  5. Energy savings using medium voltage softstarts on chip blowers

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, J. R. [E. B. Eddy Forest Products, Ltd., Espanola, ON (Canada)

    1997-05-01

    Wood chip blowers are used to pneumatically blow hardwood and softwood chips to storage piles, chip bins and batch digesters. In the past they were allowed to run continuously because it was believed that frequent stops and starts would damage the equipment. Excellent energy paybacks have been achieved with the 1994 installation of silicon controlled rectifier softstarts on the blowers, thus eliminating the cost of running the equipment under no load conditions. Installation and operation of these medium voltage softstarts on both induction and synchronous motors, the project costs and the savings realized, were described. The installation of softstarts is only one example of saving energy in the paper and pulp industry. With advances in silicon controlled rectifier technology , variable speed drives, etc., there are many other opportunities which could be implemented at relatively low cost.

  6. Practically orientated noise laws for blowers. Praxisorientierte Geraeuschgesetze fuer Ventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Bommes, H.U.; Laoutoumai, D.

    1994-08-01

    The emphasis of the present work is a general noise law for blowers, derived from the strict rules of the simiarity theory, which was first published in 1985. This noise law is of special interest, inasmuch as it implicitly contains a multitude of practical noise laws such as, for example, the oldest noise law from madison or the noise law from Daly, which can easily be attuned to the relevant requirements in practice. (orig.)

  7. Air conditioning and blowers. Special issue; Airconditioning en ventilatoren. Themanummer

    Energy Technology Data Exchange (ETDEWEB)

    Nekeman, H.E. [Multi Import, Rotterdam (Netherlands); Hol, M. [Aircool Klimaattechniek, Ridderkerk (Netherlands); Bassa, E. [ed.

    1997-06-01

    In four articles several aspects of air conditioners and blowers are discussed: the application of the newly developed electronically commutated direct current engine in high-efficiency boilers, air conditioners and cooling systems, the future for flexible synthetic cooling pipes, a description of a Mitsubishi-developed air conditioner: the Inverter Driven Multi-indoor unit, also known as the KX-system, and the importance of the private sector (houses, small businesses, cars) for the use of air conditioning installations. 8 figs.

  8. Centrifugal Blower for Personal Air Ventilation System (PAVS) - Phase 1

    Science.gov (United States)

    2015-02-01

    functionality. 15. SUBJECT TERMS COOLING SBIR REPORTS AXIAL FLOW FANS OFF THE SHELF EQUIPMENT BLOWERS LIGHTWEIGHT CENTRIFUGAL FORCE...HEAT STRESS (PHYSIOLOGY) AIR FLOW VENTILATION PORTABLE EQUIPMENT PERSONAL COOLING SYSTEMS EFFICIENCY EVAPORATION INTEGRATED SYSTEMS PROTOTYPES...gH Vn ad s ad s 4 1 4 3     is angular speed (2rpm) V is volumetric flow rate Had is the fan pumping head (in meters) g is the

  9. Analysis for damages of HPT bearings and generator blower

    Energy Technology Data Exchange (ETDEWEB)

    Gho, W. S.; Kim, G. Y.; Lee, W. G. [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    2003-10-01

    During normal operation of nuclear turbine-generator, we have found the gap volt increased on the HP turbine bearings. After a week, turbine-generator was tripped due to activating the mechanical overspeed trigger during coast down operation for refueling. On disassembling, we have found the HPT bearings melted and generator blower blades broken. Reviewing the operation and vibration data and damaged components, we have concluded 2{approx}3 blades were broken during transient operation, when generator was vented and filled with CO2 in short time after tripping of turbine-generator due to leaking hydrogen from generator 2 months ago. At this time, the surge or stall through generator blower made reverse force on the rotating blades and made 2{approx}3 blades broken. Blower blades were broken and damaged more during additional transient operation and made rotor current increased due to rubbing of damaged parts. The HPT bearings were corroded electrically and melted down by breaking minimum oil film during speed down operation. The analysis and actions were properly performed and made safe operation of nuclear turbine-generator.

  10. Robótica Educacional – Geometria da direção de triciclos com “drive governor”

    Directory of Open Access Journals (Sweden)

    Fred Santos

    2015-07-01

    Full Text Available Esse artigo aborda o projeto de robô móvel em forma de triciclo revelando características peculiares da sua geometria de direção permitindo compreender detalhes de seu dimensionamento a partir do conhecimento do ambiente com o qual ele irá interagir.

  11. Blowers: Analysis of characteristic fields of swirl-controlled radial blowers; Ventilatoren: Analyse von Kennfeldern drallgesteuerter Radialventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Grundmann, R. [I.F.I. Inst. fuer Industrieaerodynamik GmbH, Inst. der Fachhochschule, Aachen (Germany); Bommes, L. [VBI, Korschenbroich (Germany)

    2004-08-01

    Until now, the characteristic fields for different guide blade angles had to be defined experimentally. Characteristic data are derived which enable calculation of the influence of the swirl control unit on the blower characteristic field. (orig.) [German] Das Kennfeld fuer verschiedene Leitschaufelwinkel musste bisher experimentell bestimmt werden. Aus derartig gewonnenen Kennfeldern werden Kenngroessen abgeleitet, die eine rechnerische Abschaetzung des Drallreglereinflusses auf das Ventilatorkennfeld ermoeglichen. (orig.)

  12. Production Facility Prototype Blower Installation Report with 1000 Hour Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dalmas, Dale Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-04-01

    The roots blower in use at ANL for in-beam experiments and also at LANL for flow tests was sized for 12 mm diameter disks and significantly less beam heating. Currently, the disks are 29 mm in diameter, with a 12 mm FWHM Gaussian beam spot at 42 MeV and 2.86 μA on each side of the target, 5.72 μA total. The target design itself is reported elsewhere. With the increased beam heating, the helium flow requirement increased so that a larger blower was needed for a mass flow rate of 400 g/s at 2.76 MPa (400 psig). An Aerzen GM 12.4 blower was selected, and is currently being installed at the LANL facility for target and component flow testing. This report describes this blower/motor/pressure vessel package and the status of the facility preparations. The blower has been operated for 1000 hours as a preliminary investigation of long term performance, operation and possible maintenance issues. The blower performed well, with no significant change in blower head or mass flow rate developed under the operating conditions. Upon inspection, some oil had leaked out of the shaft seal of the blower. The shaft seal and bearing race have been replaced. Test results and conclusions are reported.

  13. Production Facility Prototype Blower Installation Report with 1000 Hr Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olivas, Eric Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dalmas, Dale Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-23

    The roots blower in use at ANL for in-beam experiments and also at LANL for flow tests was sized for 12 mm diameter disks and significantly less beam heating. Currently, the disks are 29 mm in diameter, with a 12 mm FWHM Gaussian beam spot at 42 MeV and 2.86 μA on each side of the target, 5.72 μA total. The target design itself is reported elsewhere. With the increased beam heating, the helium flow requirement increased so that a larger blower was needed for a mass flow rate of 400 g/s at 2.76 MPa (400 psig). An Aerzen GM 12.4 blower was selected, and is currently being installed at the LANL facility for target and component flow testing. This report describes this blower/motor/pressure vessel package and the status of the facility preparations. The blower has been operated for 1000 hours as a preliminary investigation of long-term performance, operation and possible maintenance issues. The blower performed well, with no significant change in blower head or mass flow rate developed under the operating conditions. Upon inspection, some oil had leaked out of the shaft seal of the blower. The shaft seal and bearing race have been replaced.

  14. Performance and Life Tests of a Regenerative Blower for EVA Suit Ventilation

    Science.gov (United States)

    Izenson, Michael G.; Chen, Weibo; McCormick, John; Paul, Heather L.; Jennings, Mallory A.

    2012-01-01

    Ventilation fans for future space suits must meet demanding performance specifications, satisfy stringent safety requirements for operation in an oxygen atmosphere, and be able to increase output to operate in buddy mode. A regenerative blower is an attractive choice due to its ability to meet these requirements at low operating speed. This paper describes progress in the development and testing of a regenerative blower designed to meet requirements for ventilation subsystems in future space suits. The blower includes a custom-designed motor that has significantly improved its efficiency. We have measured the blower s head/flow performance and power consumption under conditions that simulate both the normal and buddy mode operating points. We have operated the blower for TBD hours and demonstrated safe operation in an oxygen test loop at prototypical pressures. We also demonstrated operation with simulated lunar dust.

  15. Testing the rated parameters of new blowers in the Stara Jama coal mine

    Energy Technology Data Exchange (ETDEWEB)

    Zugic, M.

    1987-04-01

    Presents the findings of a joint commision of specialists from the Mining Institute in Belgrade, the Zenica coal mine and the Korfman company at the trials of two KGL-160 blowers manufactured by Korfman in the FRG. These axial blowers were being offered as replacement for old blower equipment at the Stara Jama coal mine. Describes tests carried out by the commission under various operating conditions and with differing settings of the blower blades. A special note was made of electrical consumption, noise and vibration. Details the mesurement procedures together with the instrumentation used and presents the results in three tables and one diagram. Concludes that both of the blowers tested fully met their design ratings and also complied with all the operational requirements of the Stara Jama mine. 3 refs.

  16. Blower Gun pellet injection system for W7-X

    Energy Technology Data Exchange (ETDEWEB)

    Dibon, M., E-mail: mathias.dibon@ipp.mpg.de [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Baldzuhn, J.; Beck, M. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Cardella, A. [Lehrstuhl für Nukleartechnik, TU Munich, Boltzmannstr. 15, 85748 Garching (Germany); Köchl, F. [Atominstitut, TU Wien, 1020 Vienna (Austria); Kocsis, G. [Wigner RCP, RMI, P.O. Box 49, H-1525 Budapest-114 (Hungary); Lang, P.T. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Macian-Juan, R. [Lehrstuhl für Nukleartechnik, TU Munich, Boltzmannstr. 15, 85748 Garching (Germany); Ploeckl, B. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Szepesi, T. [Wigner RCP, RMI, P.O. Box 49, H-1525 Budapest-114 (Hungary); Weisbart, W. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany)

    2015-10-15

    Highlights: • Operational principle of the ASDEX Upgrade Blower Gun. • Guiding tube properties for pellet guiding according to the requirements of W7-X. • Diagnostics for the characterization of the injection system. • Experimental procedure to investigate the performance of the Blower Gun. • Results concerning pellet speeds, mass loss, delivery efficiency and exit angle. - Abstract: Foreseen to perform pellet investigations in the new stellarator W7-X, the former ASDEX Upgrade Blower Gun was revised and revitalized. The systems operational characteristics have been surveyed in a test bed. The gun is designed to launch cylindrical pellets with 2 mm diameter and 2 mm length, produced from frozen deuterium D{sub 2}, hydrogen H{sub 2} or a gas mixture consisting of 50% H{sub 2} and 50% D{sub 2}. Pellets are accelerated by a short pulse of pressurized helium propellant gas to velocities in the range of 100–250 m/s. Delivery reliabilities at the launcher exit reach almost unity. The initial pellet mass is reduced to about 50% during the acceleration process. Pellet transfer to the plasma vessel was investigated by a first mock up guiding tube version. Transfer through this S-shaped stainless steel guiding tube (inner diameter 8 mm; length 6 m) containing two 1 m curvature radii was investigated for all pellet types. Tests were performed applying repetition rates from 2 Hz to 50 Hz and propellant gas pressures ranging from 0.1 to 0.6 MPa. For both H{sub 2} and D{sub 2}, low overall delivery efficiencies were observed at slow repetition rates, but stable efficiencies of about 90% above 10 Hz. About 10% of the mass is eroded while flying through the guiding tube. Pellets exit the guiding tube with an angular spread of less than 14°.

  17. Hand injuries from snow blowers: a report of an epidemic.

    Science.gov (United States)

    Tetz, D J; Aghababian, R

    1995-01-01

    During a record snowfall in Worcester, Massachusetts, 11-13 December 1992, 37 male patients with hand injuries suffered during snow blower operation were seen at three area hospitals. Two previous reports describe 13 patients seen over a 3-year period and 28 patients over a 12-year period. This report describes the largest number of hand injuries from snow blowers that have occurred over a 48-hour period. The snow was unusual because of the high water density in the initial 9 inches (23 cm) that fell at an average temperature of 33 degrees F (0.6 degree C) with the final depth of 30 inches (76 cm), causing the machines to become clogged. Patients admitted to reaching into a running machine in 35/37 (95%) cases, 11/37 (30%) claimed the auger and impeller blades were disengaged, and 2/37 (5%) patients claimed their injuries occurred with the engines turned off. All injuries occurred when the patients placed their hands down the chute, contacting the impeller blades. Injuries involved 32 long, 15 ring, 13 index, and five small fingers and ranged from simple lacerations to partial phalangeal amputations. The majority, 27/37 (73%), were managed in emergency departments without interventions in the operating suites. Infection occurred in one patient who had the lesion repaired in the operating suite. As in previous studies, no differences were found for the variables of snow-blower age, type, or horsepower, or on experience level or age of the operators.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. PAR Analysis of HSR Nozzles

    Science.gov (United States)

    Georgiadis, Nicholas J.

    1999-01-01

    Only recently has computational fluid dynamics (CFD) been relied upon to predict the flow details of advanced nozzle concepts. Computer hardware technology and flow solving techniques are advancing rapidly and CFD is now being used to analyze such complex flows. Validation studies are needed to assess the accuracy, reliability, and cost of such CFD analyses. At NASA Lewis, the PARC2D/3D full Navier-Stokes (FNS) codes are being applied to HSR-type nozzles. This report presents the results of two such PARC FNS analyses. The first is an analysis of the Pratt and Whitney 2D mixer-ejector nozzle, conducted by Dr. Yunho Choi (formerly of Sverdrup Technology-NASA Lewis Group). The second is an analysis of NASA-Langley's axisymmetric single flow plug nozzle, conducted by the author.

  19. Shaanxi Blower Group: One Brand with Two "China Top Brand"

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Shaanxi Blower (Group) Co., Ltd.is a group company of large engineering technology and equipment focused on design and manufacturing of turbo-machinery, a large key enterprise in China, one of the top 500 enterprises for machinery industries, one of the best 100 enterprises in income from sales of Chinese Machinery Industries in 2004,one of the largest 1000 group enterprises in China in 2004, one of the vanguard enterprises in Chinese industries in 2005,the key support enterprise aiming at 10billion in production value during the "Eleventh Five-year Plan" by Xi'an Municipal government.

  20. Characteristic estimation of radial blowers; Kennfeldabschaetzung fuer Radialventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Draxler, D. [Architekturbuero F. Draxler, Duesseldorf (Germany)

    2002-12-01

    Radial blowers are an important cost factor in space HVAC systems. For cost reduction purposes, designers are interested in a simple, time-saving method of calculating dimensions and characteristics of radial rotors with minimum hydraulic losses. The solution is based primarily on knowledge of the power loss factor. [German] Radialventilatoren verursachen einen hohen Anteil an den laufenden Betriebskosten vieler lufttechnischer Anlagen. Um diese moeglichst gering zu halten, ist der Konstrukteur an einem einfachen und zeitsparenden Entwurfsverfahren interessiert, welches die Bemessungsgroessen und Kennlinien radialer Laufraeder liefert, die minimale hydraulische Verluste aufweisen. Unter diesen Voraussetzungen basiert die Loesung des Problems im Wesentlichen auf der Kenntnis des Minderleistungsfaktors. (orig.)

  1. Shaanxi Blower Group: One Brand with Two "China Top Brand"

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

      Shaanxi Blower (Group) Co., Ltd.is a group company of large engineering technology and equipment focused on design and manufacturing of turbo-machinery, a large key enterprise in China, one of the top 500 enterprises for machinery industries, one of the best 100 enterprises in income from sales of Chinese Machinery Industries in 2004,one of the largest 1000 group enterprises in China in 2004, one of the vanguard enterprises in Chinese industries in 2005,the key support enterprise aiming at 10billion in production value during the "Eleventh Five-year Plan" by Xi'an Municipal government.……

  2. Lentes progressivas x lentes multifocais: um estudo baseado na geometria analítica do cone

    Directory of Open Access Journals (Sweden)

    Araújo Marília Cavalcante

    2004-01-01

    Full Text Available OBJETIVO: Compreender, por meio de figuras e funções matemáticas do cone, as lentes progressivas e mostrar que elas não são lentes multifocais porque, nelas, a refração da luz não obedece as leis da geometria euclidiana. MÉTODOS: Foi feito um estudo da geometria analítica do cone, com o programa de computador Auto-CAD 14, dando enfoque óptico às figuras geométricas obtidas com a sua secção. RESULTADOS: Pela análise das figuras obtidas da secção do cone, pudemos observar as superfícies que compõem as lentes progressivas. Estas superfícies são compostas de elipse, círculo, parábola e hipérbole. Diferente do que é dito na literatura, encontramos as elipses com diâmetro maior nas ordenadas e de mesmo sentido seguida por duas superfícies inferiores que são parábola e hipérbole e não o contrário. CONCLUSÕES: As lentes progressivas diferentemente das lentes multifocais apresentam prismas nos centros ópticos como decorrência da sua estrutura. No final, fizemos análise das suas formas mostrando o limite teórico da sua evolução.

  3. Dalla geometria delle preesistenze alla conoscenza della costruzione: un’esperienza di recupero aggiornata dalla metodologia BIM

    Directory of Open Access Journals (Sweden)

    Massimiliano Lo Turco

    2012-06-01

    Full Text Available Il termine costruire (lessicalmente equivale a riordinare le singole parti dell’operazione secondo il nesso logico e grammaticale; ed altresì disporle e collegarle secondo le regole e l’uso della lingua. Analogamente gli odierni strumenti BIM possiedono nelle loro corde sia una riconoscibile capacità di sviluppare progetti seguendo le regole del buon costruire, sia un puntuale controllo della geometria da cui derivano le molteplici rappresentazioni di tipo grafo-numerico. Ci si interrogherà inoltre sul rinnovato rapporto tra Rilievo e Progetto, in un ambiente particolarmente fertile ove la Geometria è indagata nelle sue poliedriche proprietà e al Disegno è affidato un ruolo di maggiore visibilità e di effettiva rilevanza.

  4. Regenerative blowers for higher pressure ratios; Seitenkanalverdichter fuer erhoehte Druckverhaeltnisse

    Energy Technology Data Exchange (ETDEWEB)

    Surek, D. [Fachhochschule Merseburg (Germany). Fachbereich Maschinenbau

    1997-10-01

    Up to now regnerative blowers are built and used only for low pressure ratios in the working range of {pi}=1.10 to 1.30 despite of their high pressure coefficients. The small outer dimensions are their essential advantage compared to other flow machines but they are mostly used with low peripheral speed. The reachable stage pressure ratio can be increased by rising the peripheral speed but the expansion flow on the block has to be considered. With regard to the expansion flow on the block two pressure ranges on the block result. The undercritical and the supercritical range of the expansion flow on the block have to be taken into consideration when designing such machines. With a multistage realization of regenerative blowers higher pressure ratios up to {pi}>2.0 are within reach. (orig.) [Deutsch] Bisher werden Seitenkanalverdichter trotz ihrer grossen Druckzahlen nur fuer geringe Druckverhaeltnisse im Auslegungsbereich von {pi}=1,10 bis 1,30 gebaut und betrieben. Ihr wesentlicher Vorteil liegt in den geringen Bauabmessungen im Vergleich zu anderen Stroemungsmaschinen, wobei sie vorwiegend mit geringen Umfangsgeschwindigkeiten betrieben werden. Durch Erhoehung der Umfangsgeschwindigkeit kann das erreichbare Stufendruckverhaeltnis betraechtlich gesteigert werden, wobei aber die Expansionsstroemung im Unterbrecher zu beruecksichtigen ist. Unter Beachtung der Expansionsstroemung im Unterbrecher ergeben sich zwei Druckbereiche fuer die Expansionsstroemung im Unterbrecher. Der unterkritische und der ueberkritische Bereich der Expansionsstroemung im Unterbrecher sind bei der konstruktiven Gestaltung der Maschinen zu beachten. Mit einer mehrstufigen Ausfuehrung von Seitenkanalverdichtern sind hoehere Druckverhaeltnisse bis {pi}>2,0 erreichbar. (orig.)

  5. Towards advanced aeration modelling: from blower to bubbles to bulk.

    Science.gov (United States)

    Amaral, Andreia; Schraa, Oliver; Rieger, Leiv; Gillot, Sylvie; Fayolle, Yannick; Bellandi, Giacomo; Amerlinck, Youri; Mortier, Séverine T F C; Gori, Riccardo; Neves, Ramiro; Nopens, Ingmar

    2017-02-01

    Aeration is an essential component of aerobic biological wastewater treatment and is the largest energy consumer at most water resource recovery facilities. Most modelling studies neglect the inherent complexity of the aeration systems used. Typically, the blowers, air piping, and diffusers are not modelled in detail, completely mixed reactors in a series are used to represent plug-flow reactors, and empirical correlations are used to describe the impact of operating conditions on bubble formation and transport, and oxygen transfer from the bubbles to the bulk liquid. However, the mechanisms involved are very complex in nature and require significant research efforts. This contribution highlights why and where there is a need for more detail in the different aspects of the aeration system and compiles recent efforts to develop physical models of the entire aeration system (blower, valves, air piping and diffusers), as well as adding rigour to the oxygen transfer efficiency modelling (impact of viscosity, bubble size distribution, shear and hydrodynamics). As a result of these model extensions, more realistic predictions of dissolved oxygen profiles and energy consumption have been achieved. Finally, the current needs for further model development are highlighted.

  6. A realistic dynamic blower energy consumption model for wastewater applications.

    Science.gov (United States)

    Amerlinck, Y; De Keyser, W; Urchegui, G; Nopens, I

    2016-10-01

    At wastewater treatment plants (WWTPs) aeration is the largest energy consumer. This high energy consumption requires an accurate assessment in view of plant optimization. Despite the ever increasing detail in process models, models for energy production still lack detail to enable a global optimization of WWTPs. A new dynamic model for a more accurate prediction of aeration energy costs in activated sludge systems, equipped with submerged air distributing diffusers (producing coarse or fine bubbles) connected via piping to blowers, has been developed and demonstrated. This paper addresses the model structure, its calibration and application to the WWTP of Mekolalde (Spain). The new model proved to give an accurate prediction of the real energy consumption by the blowers and captures the trends better than the constant average power consumption models currently being used. This enhanced prediction of energy peak demand, which dominates the price setting of energy, illustrates that the dynamic model is preferably used in multi-criteria optimization exercises for minimizing the energy consumption.

  7. The advantage of variable speed for multistage centrifugal blowers used in waste-water treatment plants

    Energy Technology Data Exchange (ETDEWEB)

    Huang, X. [Gardner Denver Incorp., Peachtree City, GA (United States)

    1999-07-01

    The multistage centrifugal blower is primarily a 60 Hz market product. A two-pole AC induction motor directly drives the blower at 3600 RPM. These blowers have been used widely for the last three decades in the US for waste water treatment plant applications (WWTP) due to their simple design and rugged construction. The cost of energy drives the market towards not only an efficient single design point but also an efficient operating range when both flow and pressure are varied. On the other hand, if a blower is running at 3000 RPM as in the 50 Hz market, about 20% of flow and 40% of pressure are lost comparing to a 60 Hz application. To meet these new market challenges, the Variable Frequency Drive (VFD) multistage centrifugal blower was designed, where the VFD serves not only as speed adjusting device to maximise the efficiency but also as a speed increaser to minimise the blower size. For existing WWTP installations, retrofit to a VFD drive requires minimum investment and leadtime while achieving drastic energy savings. A comparison with the gear drive high-speed single stage blower concept is also made. (Author)

  8. Uji Performansi Getaran Mekanis dan Kebisingan Mist Blower Yanmar MK 150-B

    Directory of Open Access Journals (Sweden)

    Ahmad Noval Irvani

    2012-10-01

    Full Text Available Mist blower is one of the mechanization tool of agriculture considered as a tool that can assist humans in fertilizer and pesticides spreading activities. Levels of motor speed in the used mist blower were 1915, 4009, and 7227 rpm. Vibration measurements were conducted on the engine and handlebar control mist blower with the three-dimensional axes namely X, Y, and Z. Mist blower noise measurements were performed on the engine, operator's right ear and left ear. Based on the analysis of vibration and noise from the mist blower of type MK 150-B was obtained the safe limit values from the use of these tools. The safe limit of the use of mist blower in motor rotation speed of 1915, 4009, and 7227 rpm after being compared with the vibration and noise were 1 hour, 1 hour and 24 minutes respectively. The farther the distance from noise source, the lower the noise level too. Moreover objectivity study of operator was conducted. The first farmer was tired faster than the second farmer. In terms of age of farmer, the second farmer (60 years older than the first farmers (40 years, but this should not affect significantly. Activity on the previous day greatly affects the level of fatigue when operating the mist blower. This was because the first farmers did more activities and had rest periods that less than second farmer.

  9. La dinamica tra appartenere e differenziarsi: elementi della trasformazione nella terapia ‘a geometria variabile’ con adolescenti migranti

    Directory of Open Access Journals (Sweden)

    Graziana Mangiacavallo

    2015-01-01

    Full Text Available In questo lavoro sarà affrontata la dinamica tra processo di appartenenza e differenziazione in età adolescenziale, attraverso l’esemplificazione di un caso clinico. Tale dinamica è resa complessa dal fatto che il caso in oggetto, rimanda a trame culturali della migrazione. Tale lavoro prende in esame la possibilità dell’utilizzo di strategie integrate, come la consultazione culturale, alla luce del modello a ‘geometria variabile.

  10. Time-frequency analysis of the Surge Onset in the Centrifugal Blower

    Directory of Open Access Journals (Sweden)

    Liskiewicz Grzegorz

    2015-09-01

    Full Text Available Time frequency analysis of the surge onset was performed in the centrifugal blower. A pressure signal was registered at the blower inlet, outlet and three locations at the impeller shroud. The time-frequency scalograms were obtained by means of the Continuous Wavelet Transform (CWT. The blower was found to successively operate in four different conditions: stable working condition, inlet recirculation, transient phase and deep surge. Scalograms revealed different spectral structures of aforementioned phases and suggest possible ways of detecting the surge predecessors.

  11. Nozzle geometry for organic vapor jet printing

    Science.gov (United States)

    Forrest, Stephen R; McGraw, Gregory

    2015-01-13

    A first device is provided. The device includes a print head. The print head further includes a first nozzle hermetically sealed to a first source of gas. The first nozzle has an aperture having a smallest dimension of 0.5 to 500 microns in a direction perpendicular to a flow direction of the first nozzle. At a distance from the aperture into the first nozzle that is 5 times the smallest dimension of the aperture of the first nozzle, the smallest dimension perpendicular to the flow direction is at least twice the smallest dimension of the aperture of the first nozzle.

  12. Operation method of circulation blower of fuel cell power generation system; Nenryo denchi hatsuden sochi no junkan buroa unten hoho

    Energy Technology Data Exchange (ETDEWEB)

    Iida, T. [Fuji Electric Co. Ltd., Tokyo (Japan)

    1998-02-13

    The conventional circulation blower of fuel cell power generation system has such problem as generating a big pressure difference between electrodes. When the blower is started, the pressure difference is caused by sudden start of suction of cell exhaust gas from the upper stream of the circulation blower since the starting is done in total voltage start by switch. When the blower is stopped, the pressure difference is also caused by sudden stop of suction of cell exhaust gas from the upper stream of the circulation blower. In the invention, the motor driving the circulation blower which circulates the cell exhaust gas of fuel cell power generation system to the cell inlet is equipped with a rotation control system (VVVF). When the blower is started, a smooth start of blower, or smooth start of suction of exhaust gas is given by the control system because the rotation speed is gradually increased from low speed. When the blower is stopped, a smooth stop of blower, or smooth stop of suction of exhaust gas is given by the control system because the rotation speed is gradually decreased from high speed to low speed. In this way, the generation of extreme pressure difference between electrodes of fuel cell can be suppressed. 2 figs.

  13. Surge investigations in a radial single-stage blower with adjustable inlet guide vanes

    Energy Technology Data Exchange (ETDEWEB)

    Kryllowicz, W.; Horodko, L.; Hanausek, P.

    1996-12-31

    Experimental investigations of the influence of adjustable inlet guide vanes on the surge propagation in a radial single-stage blower system were carried out. The object of the investigations was a blower with a semi-open impeller with radially ended blades and a vaneless diffuser. The blower maximum pressure rate was {Pi} = 1.52 at the mass flow equal to m = 13.8 kg/s. The test instrumentation used consisted of classic probes and thermocouples and fast response semi-conductor pressure transducers located in flow path walls. Additionally, the noise level for different blower operating points was measured. These investigations made it possible to identify the mild and deep surge regions, the region of an inlet recirculation phenomenon as well as an inlet reverse flow phenomenon in the function of the IGV adjustment angle. (orig.)

  14. Production Facility Prototype Blower Installation Report with 1000 Hr Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olivas, Eric Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dalmas, Dale Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-23

    The roots blower in use at ANL for in-beam experiments and also at LANL for flow tests was sized for 12 mm diameter disks and significantly less beam heating. Currently, the disks are 29 mm in diameter, with a 12 mm FWHM Gaussian beam spot at 42 MeV and 2.86 μA on each side of the target, 5.72 μA total. The target design itself is reported elsewhere. With the increased beam heating, the helium flow requirement increased so that a larger blower was need for a mass flow rate of 400 g/s at 2.76 MPa (400 psig). An Aerzen GM 12.4 blower was selected, and is currently being installed at the LANL facility for target and component flow testing. This report describes this blower/motor/pressure vessel package and the status of the facility preparations.

  15. Residential Forced Air System Cabinet Leakage and Blower Performance

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain S.; Dickerhoff, Darryl J.; Delp, William W.

    2010-03-01

    This project evaluated the air leakage and electric power consumption of Residential HVAC components, with a particular focus on air leakage of furnace cabinets. Laboratory testing of HVAC components indicated that air leakage can be significant and highly variable from unit to unit ? indicating the need for a standard test method and specifying maximum allowable air leakage in California State energy codes. To further this effort, this project provided technical assistance for the development of a national standard for Residential HVAC equipment air leakage. This standard is being developed by ASHRAE and is called"ASHRAE Standard 193P - Method of test for Determining the Air Leakage Rate of HVAC Equipment". The final part of this project evaluated techniques for measurement of furnace blower power consumption. A draft test procedure for power consumption was developed in collaboration with the Canadian General Standards Board: CSA 823"Performance Standard for air handlers in residential space conditioning systems".

  16. Pumping characteristics of roots blower pumps for light element gases

    Energy Technology Data Exchange (ETDEWEB)

    Hiroki, Seiji; Abe, Tetsuya; Tanzawa, Sadamitsu; Nakamura, Jun-ichi; Ohbayashi, Tetsuro [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2002-07-01

    The pumping speed and compression ratio of the two-stage roots blower pumping system were measured for light element gases (H{sub 2}, D{sub 2} and He) and for N{sub 2}, in order to assess validity of the ITER torus roughing system as an ITER R and D task (T234). The pumping system of an Edwards EH1200 (nominal pumping speed of 1200 m{sup 3}/s), two EH250s (ibid. 250 m{sup 3}/s) and a backing pump (ibid. 100 m{sup 3}/s) in series connection was tested under PNEUROP standards. The maximum pumping speeds of the two-stage system for D{sub 2} and N{sub 2} were 1200 and 1300 m{sup 3}/h, respectively at 60 Hz, which satisfied the nominal pumping speed. These experimental data support the design validity of the ITER torus roughing system. (author)

  17. Experimental optimization of an electric blower by corona wind

    Energy Technology Data Exchange (ETDEWEB)

    Rashkovan, A.; Sher, E.; Kalman, H. [Ben-Gurion University of the Negev, Beer Sheva (Israel). Dept. of Mechanical Engineering

    2002-10-01

    The effect of corona wind produced by stretched steel wire and two copper wings on the heat transfer from a heated horizontal plate was investigated experimentally. Although in such an arrangement the heat transfer augmentation is expected to be lower, some advantages may be postulated. In such a construction, the plate to be cooled is not a part of the wind generation system, it is not charged, the electrical field next to it is negligible, and it may be constructed from non-metallic materials. In the course of the study, optimal geometric parameters of the electric blower together with optimal value of high voltage supply have been established. Under these optimal conditions, augmentation by three times of the heat transfer coefficient over that for the natural convection has been achieved. (author)

  18. Preliminary Tests of Nose- and Side- Entrance Blower Cooling Systems for Radial Engines, Special Report

    Science.gov (United States)

    Biermann, David; Valentine, E. Floyd

    1939-01-01

    Two cowling systems intended to reduce the drag and improve the low-speed cooling characteristics of conventional radial engine cowlings were tested in model form to determine the practicability of the methods. One cowling included a blower mounted on the rear face of a large propeller spinner which drew cooling air in through side entrance ducts located behind the equivalent engine orifice plate. The air was passed through the equivalent engine orifice plate from rear to front and out through a slot between the spinner and the engine plate. The blower produced substantially all the power necessary to circulate the cooling air in some cases, so the quantity of air flowing was independent of the air speed, Two types of blowers were used, a centrifugal type and one using airfoil blades which forced the air outward from the center of rotation. The other cowling was similar to the conventional N.A.C.A. cowling except for the addition of a large propeller spinner nose. The spinner was provided with a hole in the nose to admit cooling air and blower blades to increase the pressure for cooling at low speeds. The tests show that with both cowling types the basic drag of the nacelle was reduced substantially below that for the N.A.C.A. cowling by virtue of the better nose shape made possible by the spinner . The drag due to the side-entrance ducts was nearly zero when the openings were closed or when the blower was drawing in a certain quantity of air in proportion to the air speed. The drag increased, however, when air mas allowed to spill from the openings. The nose-entrance blower showed considerable promise as a cooling means although the blower tested was relatively inefficient, owing to the fact that the blower compartments evidently were expanded too rapidly under the conditions imposed. by the design.

  19. Coronary air embolism in off-pump surgery caused by blower-mister device.

    Science.gov (United States)

    Korkmaz, Askin Ali; Guden, Mustafa; Korkmaz, Feride; Yuce, Murat

    2008-01-01

    Gaseous emboli caused by the blower-mister result in air locks within coronary vessels. We describe the case of a coronary air embolism caused by a blower-mister device on off-pump surgery. The tip of the device unexpectedly entered the coronary artery through arteriotomy and caused the air emboli. Air locks in the coronary circulation led to hemodynamic deterioration, and cardiopulmonary bypass was started following the emergency cannulation.

  20. Turbomachine combustor nozzle including a monolithic nozzle component and method of forming the same

    Energy Technology Data Exchange (ETDEWEB)

    Stoia, Lucas John; Melton, Patrick Benedict; Johnson, Thomas Edward; Stevenson, Christian Xavier; Vanselow, John Drake; Westmoreland, James Harold

    2016-02-23

    A turbomachine combustor nozzle includes a monolithic nozzle component having a plate element and a plurality of nozzle elements. Each of the plurality of nozzle elements includes a first end extending from the plate element to a second end. The plate element and plurality of nozzle elements are formed as a unitary component. A plate member is joined with the nozzle component. The plate member includes an outer edge that defines first and second surfaces and a plurality of openings extending between the first and second surfaces. The plurality of openings are configured and disposed to register with and receive the second end of corresponding ones of the plurality of nozzle elements.

  1. Simulation of a Downsized FDM Nozzle

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Pimentel, Rodrigo; Pedersen, David B.;

    2015-01-01

    This document discusses the simulat-ion of a downsized nozzle for fused deposition modelling (FDM), namely the E3D HotEnd Extruder with manufactured diameters of 200-400 μm in the nozzle tip. The nozzle has been simulated in terms of heat transfer and fluid flow giving an insight into the physical...

  2. Design of a Centrifugal Blower for a 400kg Rotary Furnace.

    Directory of Open Access Journals (Sweden)

    Sani Malami Suleiman

    2016-10-01

    Full Text Available Poor performance of a rotary furnace cannot be unconnected to failure in the design of the blower among others, This paper discuss the design of a centrifugal blower for a rotary furnace which will give the required manometric efficiency that will aid adequate combustion as required. The blower was designed to convert ‘driver’ energy to kinetic energy in the fluid by accelerating it to the outer rim of the revolving device known as the impeller. The impeller, driven by the blower shaft adds the velocity component to the fluid by centrifugally casting the fluid away from the impeller vane tips. The amount of energy given to the fluid corresponds to the velocity at the edge or vane tip of the impeller. Significance: Centrifugal blowers are applicable in furnaces such as Rotary and cupola furnace, the efficiency of these furnaces depend on the blast rate and air delivery from a well design blower. This paper will guide to achieve this aims.

  3. Are laptop ventilation-blowers a potential source of nosocomial infections for patients?

    Science.gov (United States)

    Siegmund, Katja; Hübner, Nils; Heidecke, Claus-Dieter; Brandenburg, Ronny; Rackow, Kristian; Benkhai, Hicham; Schnaak, Volker; Below, Harald; Dornquast, Tina; Assadian, Ojan; Kramer, Axel

    2010-09-21

    Inadequately performed hand hygiene and non-disinfected surfaces are two reasons why the keys and mouse-buttons of laptops could be sources of microbial contamination resulting consequently in indirect transmission of potential pathogens and nosocomial infections. Until now the question has not been addressed whether the ventilation-blowers in laptops are actually responsible for the spreading of nosocomial pathogens. Therefore, an investigational experimental model was developed which was capable of differentiating between the microorganisms originating from the external surfaces of the laptop, and from those being blown out via the ventilation-blower duct. Culture samples were taken at the site of the external exhaust vent and temperature controls were collected through the use of a thermo-camera at the site of the blower exhaust vent as well as from surfaces which were directly exposed to the cooling ventilation air projected by the laptop. Control of 20 laptops yielded no evidence of microbial emission originating from the internal compartment following switching-on of the ventilation blower. Cultures obtained at the site of the blower exhaust vent also showed no evidence of nosocomial potential. High internal temperatures on the inner surfaces of the laptops (up to 73°C) as well as those documented at the site of the blower exhaust vent (up to 56°C) might be responsible for these findings.

  4. Nozzle Bricks and Well Bricks

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaohui; Peng Xigao

    2011-01-01

    1 Scope This standard specifies the classification,brand,technical requirements,test methods,inspection rules,marking,packing,transportation,storage,and quality certificate of nozzle bricks and well bricks.This standard is applicable to unfired and fired products.

  5. Disturbances in the afflux of aerodynamically highly stressed axial blowers. Stoerungen in der Zustroemung von aerodynamisch hochbelasteten Axialventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Kosyna, G.; Krasmann, H. (Technische Univ. Braunschweig, Pfleiderer-Inst. fuer Stroemungsmaschinen (Germany))

    1992-08-01

    When installing blowers, it is not always possible to ensure an optimum fluidic afflux, which can thus produce a change in the operating behaviour compared with the design. Using as an example an axial blower blade with small hub ratio and high aerodynamic blade load, under simulated non-rotation symmetrical allflux conditions, it was possible to show that with the examined distrubance configuration no extreme worsening was produced with regard to the achievable pressure increases and efficiencies of the blower stage. (orig.).

  6. Descobrindo o número pi com geometria dinâmica

    Directory of Open Access Journals (Sweden)

    José Carlos de Souza Junior

    2012-12-01

    Full Text Available Estudantes do ensino médio tem uma visão bastante restrita do número $pi$. Este trabalho tem como objetivo apresentar os resultados de uma sequência didática aplicada a estudantes do primeiro ano do ensino médio de uma escola estadual, cujo foco central foi desenvolver atividades potencialmente motivadoras para a compreensão do número $pi$, através da razão entre o perímetro de uma circunferência e seu diâmetro, visando o reconhecimento de sua importância histórica, sua aplicabilidade e a classificação deste número como um irracional, através da linebreak experimentação e visualização do método de Arquimedes para aproximação do comprimento da circunferência por perímetros de polígonos utilizando programas de geometria dinâmica.

  7. Geometria fractal em física do solo Fractal geometry in soil physics

    Directory of Open Access Journals (Sweden)

    O.O.S. Bacchi

    1993-09-01

    Full Text Available A geometria fractal tem sido aplicada nos mais diversos ramos da ciencia, mostrando grande potencial na descrição de estruturas altamente complexas. A sua aplicação em ciência do solo tem despertado grande interesse e vem se intensificando nos últimos anos. Apesar da sua divulgação através da literatura científica internacional, de conhecido acesso por parte dos pesquisadores brasileiros, o assunto parece não ter merecido ainda a nossa atenção, a contar pela ausência do tema em nossas revistas especializadas. Tratamos aqui da conceituação básica dessa nova abordagem e de algumas aplicações em física do solo.Fractal geometry has been applied on different branches of science, showing high potential in describing complex structures. Its applications in soil science have received large attention and have been intensified in the last few years. Inspite of the large number of internationally published papers, the subject seems not having received the same attention by Brazilian soil scientists, as verified by the absence of the subject in our scientific journals. This paper presents the basic concepts of this new tool and some of its applications in soil physics.

  8. AvaliaÃÃo do software geogebra como instrumento psicopedagÃgico de ensino em geometria

    OpenAIRE

    Eimard Gomes Antunes do Nascimento

    2012-01-01

    O estudo tem por objetivo avaliar o software livre Geogebra para o ensino aprendizagem de geometria, como uma ferramenta psicopedagÃgica, com destaque aos recursos que facilitam a integraÃÃo e uso do programa com os conteÃdos curriculares, professores e alunos. O software pode ser aplicado desde as sÃries inicias do ensino fundamental, em estudos universitÃrios e em cursos a distÃncia via internet. O Geogebra à um software sobre matemÃtica dinÃmica, gratuito e de multi-plataforma para todos o...

  9. Quam maximis potest itineribus: andata e ritorno della costruzione tra immagine e modello nello spazio grafico della geometria descrittiva

    Directory of Open Access Journals (Sweden)

    Matteo Ballarin

    2012-06-01

    Full Text Available Il contributo testimonia una strategia d'insegnamento congiunto del rilievo architettonico, della geometria descrittiva e del disegno digitale concepita come un viaggio di andata e ritorno tra immagine e modello. Iniziando dalla fotogrammetria elementare e dalle tecniche di foto-modellazione offerte da software (gratuiti e dotati di un'interfaccia sufficientemente  intuitiva si possono poi introdurre – col metodo di Monge – le tecniche del rilievo topografico, giungendo alla costruzione interdefinita di un unico modello digitale degli oggetti del rilievo. Il circolo didattico si chiude poi costruendo rappresentazioni tabulari tradizionali dei modelli.

  10. A geometria das rodas cilíndricas de engrenagens exteriores com perfil em evolvente de circulo

    OpenAIRE

    José Almacinha; Faria, P.; Joaquim Fonseca; Jorge Seabra

    1992-01-01

    O projecto de modernos sistemas de engrenamento, para operarem em regimes de grandes potências e elevadas velocidades, recorre cada vez com maior frequência à Concepção Assistida por Computador apoiada em códigos do Método dos Elementos Finitos e do Método dos Elementos Fronteira. A correcta definição da geometria do perfil dos dentes das rodas é fundamental para a credibilidade dos resultados obtidos.A definição geométrica do perfil dos dentes pode também assumir um papel importante no ensin...

  11. Desenvolvimento dos conteúdos de cilindro, cone e esfera para um ambiente hipermídia voltado à geometria

    OpenAIRE

    2000-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Fundamentada nas contribuições da ergonomia, principalmente a cognitiva, esta dissertação apresenta o desenvolvimento dos módulos referentes a cilindro, cone e esfera, que será integrado no Geometrando (ambiente hipermídia voltado para o ensino de Geometria). Sua intenção é contribuir para que o aprendizado seja mais eficiente, com um módulo computacional de acesso livre às informações. O diferencial desta...

  12. Matemática e arte : explorando a geometria dos fractais e as tesselações de Escher

    OpenAIRE

    Camila de Fátima Modesto

    2015-01-01

    Esta pesquisa consistiu em apresentar propostas de ensino de Matemática utilizando conexões entre a Matemática e a Arte. O trabalho proposto explorou a Geometria dos Fractais e as obras do artista gráfico Maurits Cornelis Escher, trabalhando conceitos matemáticos através da observação e construções de fractais, como também a exploração das obras do artista. As atividades propostas empregaram o uso de tecnologias, como softwares que permitem um ensino dinâmico facilitando a visualização dos ob...

  13. Olhares que pensam e sentem: arte e mediação cultural na aula de geometria

    OpenAIRE

    2011-01-01

    Esta pesquisa se caracteriza como qualitativa, porque parte de um levantamento teórico a respeito do ensino e aprendizagem da arte e da geometria e das suas relações. Com dados predominantemente descritivos, análise detalhada do processo e conclusões que seguem por raciocínio indutivo a partir dos dados. O foco da pesquisa está nos “olhares que pensam e sentem”, envolvendo professores e alunos das séries iniciais do Ensino Fundamental de uma prefeitura no interior do estado de São Paulo, busc...

  14. Spray nozzle for fire control

    Science.gov (United States)

    Papavergos, Panayiotis G.

    1990-09-01

    The design of a spray nozzle for fire control is described. It produces a spray of gas and liquid having an oval transverse cross section and it comprises a mixing chamber with an oval transverse cross section adapted to induce a toroidal mixing pattern in pressurized gas and liquid introduced to the mixing chamber through a plurality of inlets. In a preferred embodiment the mixing chamber is toroidal. The spray nozzle produces an oval spray pattern for more efficient wetting of narrow passages and is suitable for fire control systems in vehicles or other confined spaces. Vehicles to which this invention may be applied include trains, armoured vehicles, ships, hovercraft, submarines, oil rigs, and most preferably, aircraft.

  15. Frozen Chemistry Effects on Nozzle Performance Simulations

    Science.gov (United States)

    Yoder, Dennis A.; Georgiadis, Nicholas J.; O'Gara, Michael R.

    2009-01-01

    Simulations of exhaust nozzle flows are typically conducted assuming the gas is calorically perfect, and typically modeled as air. However the gas inside a real nozzle is generally composed of combustion products whose thermodynamic properties may differ. In this study, the effect of gas model assumption on exhaust nozzle simulations is examined. The three methods considered model the nozzle exhaust gas as calorically perfect air, a calorically perfect exhaust gas mixture, and a frozen exhaust gas mixture. In the latter case the individual non-reacting species are tracked and modeled as a gas which is only thermally perfect. Performance parameters such as mass flow rate, gross thrust, and thrust coefficient are compared as are mean flow and turbulence profiles in the jet plume region. Nozzles which operate at low temperatures or have low subsonic exit Mach numbers experience relatively minor temperature variations inside the nozzle, and may be modeled as a calorically perfect gas. In those which operate at the opposite extreme conditions, variations in the thermodynamic properties can lead to different expansion behavior within the nozzle. Modeling these cases as a perfect exhaust gas flow rather than air captures much of the flow features of the frozen chemistry simulations. Use of the exhaust gas reduces the nozzle mass flow rate, but has little effect on the gross thrust. When reporting nozzle thrust coefficient results, however, it is important to use the appropriate gas model assumptions to compute the ideal exit velocity. Otherwise the values obtained may be an overly optimistic estimate of nozzle performance.

  16. Proposta didática para o ensino de geometria espacial reutilizando materiais

    Directory of Open Access Journals (Sweden)

    Eliane Vasconcelos Santos

    2012-12-01

    Full Text Available Novas estratégias e metodologias têm sido foco de interesse na educação matemática a fim de auxiliar no processo de ensino-aprendizagem, bem como na intenção de dar sentido àquilo que é ensinado. Com a elaboração deste trabalho visamos verificar se a construção dos sólidos geométricos com a reutilização de materiais pode despertar nos alunos o desenvolvimento de competências matemáticas além de fazer a correlação da matemática com as demais áreas do conhecimento e demonstrar sua importância nas mais variadas situações presentes no dia a dia que nem sempre são percebidas. A aplicação da atividade aconteceu em uma turma do 3ª ano do ensino médio. Os resultados obtidos foram satisfatórios, tendo em vista que os alunos se aproximaram de conhecimentos, com os quais poderão criar relações sociais constituídas de sensibilidade, criatividade e criticidade, características essenciais para a construção de novos saberes.Palavras-chave: ensino da matemática; geometria espacial; sólidos geométricos; reutilização de materiais.

  17. Blower Gun pellet injection system for W7-X

    Energy Technology Data Exchange (ETDEWEB)

    Dibon, Mathias; Baldzuhn, Juergen; Beck, Michael; Lang, Peter; Ploeckl, Bernhard; Weisbart, Wolfgang [MPI fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching (Germany); Cardella, Antonio; Macian-Juan, Rafael [Lehrstuhl fuer Nukleartechnik, TU Munich, Boltzmannstr. 15, 85748 Garching (Germany); Koechl, Florian [Association EURATOM-OeAW/ATI, Atominstitut, TU Wien, 1020 Vienna (Austria); Kocsis, Gabor; Szepesi, Tamas [Wigner RCP, RMI, EURATOM Association, P.O.Box 49, H-1525 Budapest-114 (Hungary)

    2014-07-01

    Foreseen to serve for the new stellarator W7-X for pellet investigations, the former ASDEX Upgrade Blower Gun was revised and revitalized in a test bed. The gun is able now to launch cylindrical pellets of 2 mm diameter and 2 mm length, produced from frozen Deuterium (D{sub 2}) or Hydrogen (H{sub 2}). Pellets are accelerated by a short pulse of pressurized helium propellant gas to velocities in the range of 100-250 m/s. Delivery reliabilities at the launcher exit close to unity are achieved. For pellet transfer to the plasma vessel a first mock up guiding tube version was investigated. Transfer through this S-shaped (inner diameter 8 mm; length 6 m) stainless steel guiding tube containing two 1 m curvature radii was investigated for both H{sub 2} and D{sub 2} pellets. Tests were performed applying repetition rates from 2 Hz to 50 Hz and propellant gas pressures ranging from 1 bar to 6 bar. For both H{sub 2} and D{sub 2}, low overall delivery efficiencies were observed at slow repetition rates, but stable efficiencies of about 90% above 10 Hz.

  18. Hermatically sealed motor blower unit with stator inside hollow armature

    Science.gov (United States)

    Donelian, Khatchik O.

    1976-01-20

    13. A hermetically sealed motor blower unit comprising, in combination, a sealed housing having a thrust plate mounted therein and having a re-entrant wall forming a central cavity in said housing, a rotor within said housing, said rotor comprising an impeller, a hollow shaft embracing said cavity and a thrust collar adapted to cooperate with said thrust plate to support the axial thrust of said shaft, one or more journal bearings within said housing for supporting the radial load of said shaft and electric motor means for rotating said rotor, said motor means comprising a motor-stator located within said cavity and adapted to cooperate through a portion of said re-entrant wall with a motor-rotor mounted within said hollow shaft, the portion of said re-entrant wall located between said motor-stator and said motor-rotor being made relatively thin to reduce electrical losses, the bearing surfaces of said thrust plate, thrust collar and journal bearings being in communication with the discharge of said impeller, whereby fluid pumped by said impeller can flow directly to said bearing surfaces to lubricate them.

  19. Whistle-blower accuses VA inspector general of a "whitewash"

    Directory of Open Access Journals (Sweden)

    Robbins RA

    2014-09-01

    Full Text Available No abstract available. Article truncated after 150 words. Yesterday, Dr. Sam Foote, the initial whistle-blower at the Phoenix VA, criticized the Department of Veterans Affairs inspector general's (VAOIG report on delays in healthcare at the Phoenix VA at a hearing before the House Committee of Veterans Affairs (1,2. Foote accused the VAOIG of minimizing bad patient outcomes and deliberately confusing readers, downplaying the impact of delayed health care at Phoenix VA facilities. "At its best, this report is a whitewash. At its worst, it is a feeble attempt at a cover-up," said Foote. Foote earlier this year revealed that as many as 40 Phoenix patients died while awaiting care and that the Phoenix VA maintained secret waiting lists while under-reporting patient wait times for appointments. His disclosures triggered the national VA scandal. Richard Griffin, the acting VAOIG, said that nearly 300 patients died while on backlogged wait lists in the Phoenix VA Health Care System, a much higher ...

  20. 42 CFR 84.142 - Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators...

    Science.gov (United States)

    2010-10-01

    ... air blowers; Type A supplied-air respirators; minimum requirements. 84.142 Section 84.142 Public....142 Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators; minimum requirements. (a) Blowers shall be designed and constructed to deliver an adequate amount of...

  1. Speed adjustment of blowers in refrigeration engineering. Exemplary applications; Verfahren der Drehzahlveraenderung von Ventilatoren in der Kaeltetechnik. Beispiel verschiedener Anwendungsfaelle

    Energy Technology Data Exchange (ETDEWEB)

    Albig, J. [Ziehl-Abegg AG, Kuenzelsau (Germany)

    2007-02-15

    Apart from the motor performance, also the investment cost of speed adjustment systems decide the economic efficiency of blowers. The blower performance itself is left out of account in this investigation. The most common control strategies are investigated, i.e. voltage control, frequence control, and EC technology. (orig.)

  2. Geometria na educação infantil: da manipulação empirista ao concreto piagetiano

    Directory of Open Access Journals (Sweden)

    Simone de Souza

    2012-01-01

    Full Text Available Refletir sobre os conhecimentos de geometria do professor de educação infantil e as concepções epistemológicas que fundamentam suas condutas pedagógicas foi o objetivo de nossa pesquisa. A análise dos discursos indicou boa vontade das professoras para o trabalho geométrico, entretanto o desconhecimento da geometria enquanto teoria e a enraizada concepção epistemológica empirista, reportaram à ideia de que este conhecimento está nos objetos, bastando sua manipulação para que haja aprendizagem. Assim, caberia às crianças, por meio de estímulos e da organização dos materiais manipuláveis pelos docentes, a descoberta das formas geométricas presentes no mundo que as rodeia. Buscamos, na epistemologia genética de Jean Piaget, as bases sólidas para contribuições à reflexão e atuação de professores.

  3. Variable volume combustor with pre-nozzle fuel injection system

    Energy Technology Data Exchange (ETDEWEB)

    Keener, Christopher Paul; Johnson, Thomas Edward; McConnaughhay, Johnie Franklin; Ostebee, Heath Michael

    2016-09-06

    The present application provides a combustor for use with a gas turbine engine. The combustor may include a number of fuel nozzles, a pre-nozzle fuel injection system supporting the fuel nozzles, and a linear actuator to maneuver the fuel nozzles and the pre-nozzle fuel injection system.

  4. Four-channel accelerometer for diagnostic testing of roller bearings of mine blowers

    Energy Technology Data Exchange (ETDEWEB)

    Lebiedzki, A.

    1992-01-01

    Discusses design, operation and use of a four-channel vibroacoustic monitoring system for control of the main blowers driven by electric motors with a revolution rate of 500 rpm and 1 MW power. The PPWa-22PN piezoelectric acceleration converters manufactured by the EKCEL plant in Katowice were used. The converters were equipped with built-in preamplifiers that enabled measuring cables up to 100 m long to be used. The converters were mounted on the casings of blower roller bearings. Rising acoustic emission and mechanical vibrations measured and recorded by the system were signalled to a driver by three lamps (green, yellow and red ones) showing acoustic emission increase by 2 dB, 4 dB or 6 dB. Reliability of blower control using the system is discussed. 3 refs.

  5. Blowers in industrial use III. Proceedings; Ventilatoren im industriellen Einsatz III. Tagungsband

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This VDI Report comprises 36 papers presented at this conference which deal with calculation, design and performance of blowers in industrial use. The proceedings volume addresses engineers and scientists in the research, development and design departments of blower production and plant construction companies. Blower operators, researchers and university teachers may be interested as well. (orig/AKF) [Deutsch] Der VDI Bericht enthaelt 36 Vortraege dieser Tagung, die die Fortschritte auf den Gebieten fer Berechnung, Kostruktion and des Betriebsverhaltens von Ventilatoren fuer verschiedene industrielle Anwendungsfaelle wiedergeben. Der Tagungsband richtet sich an Ingenieure und Wissenschaftler von Unternehmen der Ventilatorherstellung und des Anlagebaus aus den Bereichen Forschung und Entwicklung sowie Konstruktion. Ebenfalls werden damit Betreiber und auf diesem Gebiet taetige Forscher und Hochschullehrer angesprochen. (orig/AKF)

  6. The blower: a useful tool to complete thrombectomy of the mechanical prosthetic valve.

    Science.gov (United States)

    Aroussi, Aziz Alami; Sami, Ibrahim Mohamed; Leguerrier, Alain; Verhoye, Jean Phillippe

    2006-05-01

    Thrombectomy could be an excellent approach on one condition (ie, that all parts of the thrombus are removed). We propose to use a tool (ie, the blower) to complete thrombectomy of the prosthetic mechanical valve. The blower is a vaporizer that mixes air and heparinized saline with regulator of flow and proportion used in beating heart surgery. For thrombectomy, we have modified the air-water mixing part and intensity until we obtained a jet that enabled us to remove the micro thrombus that covered the prosthetic valve and surrounding tissues. The blower completely cleaned the prosthetic valve. With this tool, thrombectomy seems easier, more complete, and more reliable with the advantages of short cross-clamping time.

  7. Effect of diffuser width on rotating stall in centrifugal blower with vaneless diffuser

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.H. [Small and Medium Industry Promotion Corporation (Korea); Cho, K.R. [Yonsei University, Seoul (Korea)

    2001-10-01

    It is generally known that radial vane blowers with vaneless diffuser may generate mostly only a rotating stall but backward curved vane blowers may do both an impeller and a diffuser rotating stalls. In this study, it was found from the numerical and experimental results that the diffuser rotating stall does not appear in a radial vane because of the suppression for the diffuser stall appearance by occuring of impeller rotating stall in a large flow rate coefficient. The diffuser rotating stalls occurring when the width of diffuser is broaden for a backward curved vane blower are classified definitely by the diffuser flow rate coefficient defined by adopting the varying diffuser width. (author). 12 refs., 9 figs.

  8. OPTIMIZING IMPELLER GEOMETRY FOR PERFORMANCE ENHANCEMENT OF A CENTRIFUGAL BLOWER USING THE TAGUCHI QUALITY CONCEPT

    Directory of Open Access Journals (Sweden)

    R RAGOTH SINGH

    2012-10-01

    Full Text Available As the diffusion of flow process is highly complex in centrifugal blower operation, it is necessary to design / develop the geometry of impeller and casing to reduce the flow losses significantly. In the present study, the methodology to find near optimum combination of blower operating variables for performance enhancement were analyzed using computational fluid dynamics(CFD. Taguchi orthogonal array (OA based design of experiments (DoE technique determines the required experimental trials. The experimental results are justifiedby Analysis of Variance (ANOVA and confirmed by conformation experiments. The parameters chosen for design optimization are Impeller outlet diameter, Impeller wheel width, Thickness of blade and Impeller inlet diameter. The levels for the parametric specification are chosen from the ranges where the blower will get thebest efficiency. CFD results were validated by the fine conformity between the CFD results and the experimental results.

  9. Retrofit device to improve vapor compression cooling system performance by dynamic blower speed modulation

    Science.gov (United States)

    Roth, Robert Paul; Hahn, David C.; Scaringe, Robert P.

    2015-12-08

    A device and method are provided to improve performance of a vapor compression system using a retrofittable control board to start up the vapor compression system with the evaporator blower initially set to a high speed. A baseline evaporator operating temperature with the evaporator blower operating at the high speed is recorded, and then the device detects if a predetermined acceptable change in evaporator temperature has occurred. The evaporator blower speed is reduced from the initially set high speed as long as there is only a negligible change in the measured evaporator temperature and therefore a negligible difference in the compressor's power consumption so as to obtain a net increase in the Coefficient of Performance.

  10. Retrofit device to improve vapor compression cooling system performance by dynamic blower speed modulation

    Energy Technology Data Exchange (ETDEWEB)

    Roth, Robert Paul; Hahn, David C.; Scaringe, Robert P.

    2015-12-08

    A device and method are provided to improve performance of a vapor compression system using a retrofittable control board to start up the vapor compression system with the evaporator blower initially set to a high speed. A baseline evaporator operating temperature with the evaporator blower operating at the high speed is recorded, and then the device detects if a predetermined acceptable change in evaporator temperature has occurred. The evaporator blower speed is reduced from the initially set high speed as long as there is only a negligible change in the measured evaporator temperature and therefore a negligible difference in the compressor's power consumption so as to obtain a net increase in the Coefficient of Performance.

  11. Pulmonary embolism caused by a carbon dioxide blower during off-pump coronary artery bypass grafting.

    Science.gov (United States)

    Hirata, Naoyuki; Kanaya, Noriaki; Yamazaki, Yutaka; Sonoda, Hajime; Namiki, Akiyoshi

    2010-02-01

    We report a rare case of pulmonary embolism (PE) caused by a carbon dioxide (CO2) blower during off-pump coronary artery bypass grafting (OPCAB). When the anastomosis of the right internal thoracic artery to left anterior descending artery was performed, the operator tore the right ventricle outflow track (RVOT) that was adjacent to the left anterior descending artery. Immediately after the anastomosis and repair of the torn RVOT with CO2 blower, the systolic pulmonary artery pressure (PAP) increased from 28 to 64 mmHg, and end-tidal CO2 decreased from 32 to 12 mmHg. Because transesophageal echocardiograph (TEE) showed numerous gas bubbles in the main pulmonary artery, we diagnosed PE caused by invasion of CO2 gas bubbles via the torn RVOT. Although a CO2 blower is useful to enhance visualization of the anastomosis during OPCAB, it should not be used for the venous system because it may cause CO2 embolism.

  12. High-velocity, multistage, nozzled, ion driven wind generator and method of operation of the same adaptable to mesoscale realization

    Science.gov (United States)

    Dunn-Rankin, Derek (Inventor); Rickard, Matthew J. A. (Inventor)

    2011-01-01

    Gas flows of modest velocities are generated when an organized ion flux in an electric field initiates an ion-driven wind of neutral molecules. When a needle in ambient air is electrically charged to a potential sufficient to produce a corona discharge near its tip, such a gas flow can be utilized downstream of a ring-shaped or other permeable earthed electrode. In view of the potential practical applications of such devices, as they represent blowers with no moving parts, a methodology for increasing their flow velocities includes exploitation of the divergence of electric field lines, avoidance of regions of high curvature on the second electrode, control of atmospheric humidity, and the use of linear arrays of stages, terminating in a converging nozzle. The design becomes particularly advantageous when implemented in mesoscale domains.

  13. Using CO to Determine Inhaled Contaminant Volumes and Blower Effectiveness in Several Types of Respirators

    Directory of Open Access Journals (Sweden)

    Arthur T. Johnson

    2011-01-01

    Full Text Available This experiment was conducted to determine how much contaminant could be expected to be inhaled when overbreathing several different types of respirators. These included several tight-fitting and loose-fitting powered air-purifying respirators (PAPRs and one air-purifying respirator (APR. CO2 was used as a tracer gas in the ambient air, and several loose-and tight-fitting respirators were tested on the head form of a breathing machine. CO2 concentration in the exhaled breath was monitored as well as CO2 concentration in the ambient air. This concentration ratio was able to give a measurement of protection factor, not for the respirator necessarily, but for the wearer. Flow rates in the filter/blower inlet and breathing machine outlet were also monitored, so blower effectiveness (defined as the blower contribution to inhaled air could also be determined. Wearer protection factors were found to range from 1.1 for the Racal AirMate loose-fitting PAPR to infinity for the 3M Hood, 3M Breath-Easy PAPR, and SE 400 breath-responsive PAPR. Inhaled contaminant volumes depended on tidal volume but ranged from 2.02 L to 0 L for the same respirators, respectively. Blower effectiveness was about 1.0 for tight-fitting APRs, 0.18 for the Racal, and greater than 1.0 for two of the loose-fitting PAPRs. With blower effectiveness greater than 1.0, some blower flow during the exhalation phase contributes to the subsequent inhalation. Results from this experiment point to different ways to measure respirator efficacy.

  14. Using CO(2) to determine inhaled contaminant volumes and blower effectiveness in several types of respirators.

    Science.gov (United States)

    Johnson, Arthur T; Koh, Frank C; Scott, William H; Rehak, Timothy E

    2011-01-01

    This experiment was conducted to determine how much contaminant could be expected to be inhaled when overbreathing several different types of respirators. These included several tight-fitting and loose-fitting powered air-purifying respirators (PAPRs) and one air-purifying respirator (APR). CO(2) was used as a tracer gas in the ambient air, and several loose-and tight-fitting respirators were tested on the head form of a breathing machine. CO(2) concentration in the exhaled breath was monitored as well as CO(2) concentration in the ambient air. This concentration ratio was able to give a measurement of protection factor, not for the respirator necessarily, but for the wearer. Flow rates in the filter/blower inlet and breathing machine outlet were also monitored, so blower effectiveness (defined as the blower contribution to inhaled air) could also be determined. Wearer protection factors were found to range from 1.1 for the Racal AirMate loose-fitting PAPR to infinity for the 3M Hood, 3M Breath-Easy PAPR, and SE 400 breath-responsive PAPR. Inhaled contaminant volumes depended on tidal volume but ranged from 2.02  L to 0  L for the same respirators, respectively. Blower effectiveness was about 1.0 for tight-fitting APRs, 0.18 for the Racal, and greater than 1.0 for two of the loose-fitting PAPRs. With blower effectiveness greater than 1.0, some blower flow during the exhalation phase contributes to the subsequent inhalation. Results from this experiment point to different ways to measure respirator efficacy.

  15. Aerosol generation by blower motors as a bias in assessing aerosol penetration into cabin filtration systems.

    Science.gov (United States)

    Heitbrink, William A; Collingwood, Scott

    2005-01-01

    In cabin filtration systems, blower motors pressurize a vehicle cabin with clean filtered air and recirculate air through an air-conditioning evaporator coil and a heater core. The exposure reduction offered by these cabins is evaluated by optical particle counters that measure size-dependent aerosol concentration inside and outside the cabin. The ratio of the inside-to-outside concentration is termed penetration. Blower motors use stationary carbon brushes to transmit an electrical current through a rotating armature that abrades the carbon brushes. This creates airborne dust that may affect experimental evaluations of aerosol penetration. To evaluate the magnitude of these dust emissions, blower motors were placed in a test chamber and operated at 12 and 13.5 volts DC. A vacuum cleaner drew 76 m3/hour (45 cfm) of air through HEPA filters, the test chamber, and through a 5 cm diameter pipe. An optical particle counter drew air through an isokinetic sampling probe and measured the size-dependent particle concentrations from 0.3 to 15 microm. The concentration of blower motor aerosol was between 2 x 10(5) and 1.8 x 10(6) particles/m3. Aerosol penetration into three stationary vehicles, two pesticide application vehicles and one tractor were measured at two conditions: low concentration (outside in the winter) and high concentration (inside repair shops and burning incense sticks used as a supplemental aerosol source). For particles smaller than 1 microm, the in-cabin concentrations can be explained by the blower motor emissions. For particles larger than 1 microm, other aerosol sources, such as resuspended dirt, are present. Aerosol generated by the operation of the blower motor and by other sources can bias the exposure reduction measured by optical particle counters.

  16. Using CO2 to Determine Inhaled Contaminant Volumes and Blower Effectiveness in Several Types of Respirators

    Science.gov (United States)

    Johnson, Arthur T.; Koh, Frank C.; Scott, William H.; Rehak, Timothy E.

    2011-01-01

    This experiment was conducted to determine how much contaminant could be expected to be inhaled when overbreathing several different types of respirators. These included several tight-fitting and loose-fitting powered air-purifying respirators (PAPRs) and one air-purifying respirator (APR). CO2 was used as a tracer gas in the ambient air, and several loose-and tight-fitting respirators were tested on the head form of a breathing machine. CO2 concentration in the exhaled breath was monitored as well as CO2 concentration in the ambient air. This concentration ratio was able to give a measurement of protection factor, not for the respirator necessarily, but for the wearer. Flow rates in the filter/blower inlet and breathing machine outlet were also monitored, so blower effectiveness (defined as the blower contribution to inhaled air) could also be determined. Wearer protection factors were found to range from 1.1 for the Racal AirMate loose-fitting PAPR to infinity for the 3M Hood, 3M Breath-Easy PAPR, and SE 400 breath-responsive PAPR. Inhaled contaminant volumes depended on tidal volume but ranged from 2.02 L to 0 L for the same respirators, respectively. Blower effectiveness was about 1.0 for tight-fitting APRs, 0.18 for the Racal, and greater than 1.0 for two of the loose-fitting PAPRs. With blower effectiveness greater than 1.0, some blower flow during the exhalation phase contributes to the subsequent inhalation. Results from this experiment point to different ways to measure respirator efficacy. PMID:21792358

  17. Through an Annular Turbine Nozzle

    Directory of Open Access Journals (Sweden)

    Rainer Kurz

    1995-01-01

    is located in the gas turbine. The experiments were performed using total pressure probes and wall static pressure taps. The pitch variation modifies the flow field both upstream and downstream of the nozzle, although the experiments show that the effect is localized to the immediate neighborhood of the involved blades. The effects on the wakes and on the inviscid flow are discussed separately. The mean velocities show a strong sensitivity to the changes of the pitch, which is due to a potential flow effect rather than a viscous effect.

  18. Blowers in technical systems - with and without spiral casing; Ventilatoreinsatz in Geraeten - mit oder ohne Spiralgehaeuse

    Energy Technology Data Exchange (ETDEWEB)

    Anschuetz, J. [Gebhardt Ventilatoren, Waldenburg (Germany); Haertel, S. [Gebhardt Ventilatoren, Waldenburg (Germany)

    1996-08-01

    Blowers without casings are used wherever there is little space for installation - in recent years increasingly also in air conditioning systems. This contribution shows how the economic efficiency of the two types of systems can be compared in order to facilitate the choice of blower. (orig.) [Deutsch] In engsten Einbauraeumen ist in einer Vielzahl von Geraeten ein Ventilatorlaufrad ohne Ventilatorgehaeuse zu finden - seit einigen Jahren auch zunehmend in Klimageraeten als Alternative zum herkoemmlichen Spiralgehaeuseventilator. Im folgenden soll verdeutlicht werden, wie diese Konzepte in ihrem physikalischen Wirkungsprinzip, vorranging unter Beruecksichtigung der Wirtschaftlichkeit im Betrieb, verglichen werden koennen, um eine Auswahl zu erleichtern. (orig.)

  19. Characteristics of faces and centrifugal blowers in a system for air distribution control in a mine

    Energy Technology Data Exchange (ETDEWEB)

    Vasilenko, V.I.; Frolov, M.A. (Novocherkasskii Politekhnicheskii Institut (USSR))

    1990-04-01

    Analyzes operation of ventilation systems of underground coal mines on the example of the Rostovugol' mines in the USSR. Systems with types VTs and VTsD main centrifugal blowers are evaluated. Mathematical formulae and functions that characterize ventilation of longwall faces and mining levels are derived and plotted. Static and dynamic characteristics of working faces and the main centrifugal blowers are analyzed. A method for optimization of ventilation systems of underground coal mines is developed; its accuracy was verified on the basis of statistical data from Rostovugol'. 6 refs.

  20. New computer-assisted design of blower convectors; Neue computerunterstuetzte Auslegung von Geblaesekonvektoren

    Energy Technology Data Exchange (ETDEWEB)

    Enzensperger, M. [Axair GmbH, Garching-Hochbrueck (Germany)

    1999-08-01

    The problem is well-known: in the air conditioning market, an increasing trends towards blower convectors has emerged recently. Often the devices are exactly tailored to special applications, requiring accurate rating. The design of blower convectors must correspond to planning specifications. The available technical data deviate from the standard data sheets of manufacturers. (orig.) [German] Wer kennt das Problem nicht: In letzter Zeit ist auf dem Klimamarkt ein verstaerkter Trend zu Geblaesekonvektoren festzustellen. Die Projekte werden oft speziell auf die Anwendungsfaelle zugeschnitten und erfordern eine genauere Auslegung. Gemaess den Angaben eines Planers muss ein Geblaesekonvektor ausgelegt werden. Die vorliegenden technischen Daten weichen von den Standard-Herstellerangaben ab. (orig.)

  1. A constant air flow rate control of blower for residential applications

    Energy Technology Data Exchange (ETDEWEB)

    Yang, S.M. [Tamkang Univ., Taipei (Taiwan, Province of China). Dept. of Mechanical Engineering

    1998-03-01

    This paper presents a technique to control a blower for residential applications at constant air flow rate using an induction motor drive. The control scheme combines a variable volt/hertz ratio inverter drive and an average motor current regulation loop to achieve control of the motor torque-speed characteristics, consequently controlling the air flow rate of the blower which the motor is driving. The controller is simple to implement and practical for commercialization. It is also reliable, since no external pressure or air flow sensor is required. Both a theoretical derivation and an experimental verification for the control scheme are presented in this paper.

  2. Measurements of airtightness of building components using the blower door method - DB Hamm; Bestimmung der Luftdichtheit von einzelnen Gebaeudeteilen mit Hilfe der Blower-Door-Methode - DB Hamm

    Energy Technology Data Exchange (ETDEWEB)

    Heinrich, H.; Dahlem, K.H.; Rechenbach, O.

    2001-08-24

    The blower door measuring system consisted of a variable frame with airtight foil and integrated speed-controlled blower, a volume flow meter and differential pressure manometer. It was not possible in all cases to generate sufficient volume flow for achieving the desired pressure gradient, both in the atrium and the building as a whole. In these cases, only the volume flow for a pressure gradient was measured. The curve was approximated using typical curves, and an n{sub 50} value was extrapolated which is not a real n{sub 50} value but an estimated value based on the values measured for low pressure gradients. Extensive measurements were carried out on different parts of the building.

  3. Flow and Noise from Septa Nozzles

    Science.gov (United States)

    Zaman, K. B. M. Q.; Bridges, J. E.

    2017-01-01

    Flow and noise fields are explored for the concept of distributed propulsion. A model-scale experiment is performed with an 8:1 aspect ratio rectangular nozzle that is divided into six passages by five septa. The septa geometries are created by placing plastic inserts within the nozzle. It is found that the noise radiation from the septa nozzle can be significantly lower than that from the baseline rectangular nozzle. The reduction of noise is inferred to be due to the introduction of streamwise vortices in the flow. The streamwise vortices are produced by secondary flow within each passage. Thus, the geometry of the internal passages of the septa nozzle can have a large influence. The flow evolution is profoundly affected by slight changes in the geometry. These conclusions are reached by mostly experimental results of the flowfield aided by brief numerical simulations.

  4. Experimental study on the aerodynamic performance of 3-dimensional vortex-blowers. Sanjigen uzuryu blower no kuriki seino ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, S.; Ito, E.; Fujio, M.; Fujita, H. (Hitachi, Ltd., Tokyo (Japan))

    1992-10-25

    Vortex blowers with two-dimensional blades have such deficiencies as low aerodynamic performance and high noise. Accordingly, discussions have been given on effects of three-dimensionalized blades on internal flows and aerodynamic performance with the objective of making the vortex blowers smaller in size, higher in performance, and lower in noise. A spiral flow exists in the flow path in a casing, which has its flow velocity increased as the flow rate is decreased. The flow velocity at the closing point reaches about two times as large as the circumferential speed of the blades in the case of having three-dimensional leading blades. The spiral flow outflowing from outer circumference of the blades into the casing flow path has its flow velocity nearly halved while swirling in semi-circular form in the casing flow path, by which a vortex blower converts the total pressure in the casing flow path to a static pressure. When the outlet angle in the axial direction is changed from 90[degree] (two-dimensional blade) to 50[degree](three-dimensional leading blade), the flow velocity components increase largely in the circumferential direction, with the pressure coefficient and the dynamic coefficient increasing by about two fold respectively. When the inlet angle in the axial direction is reduced to 40[degree] , the blade incident loss reduces, while the pressure coefficient improves by about 20% and the heat insulation efficiency by about 30%. 4 refs., 15 figs., 1 tab.

  5. `CMLe` blower for houses saves 50% energy; Woonhuisventilator CMLe bespaart 50% energie

    Energy Technology Data Exchange (ETDEWEB)

    De Vries, H. [J.E. Stork Ventilatoren, Zwolle (Netherlands)

    1998-01-01

    One of the energy saving techniques to reduce the emission of CO2 is the use of an energy efficient direct current motor in a newly StorkAir developed blower for houses. A brief description of the innovation is given. 1 fig., 2 ills.

  6. Safety and efficiency keys to {open_quotes}surgeless blower{close_quotes}

    Energy Technology Data Exchange (ETDEWEB)

    Banyay, H.D.; Gutzwiller, L.

    1997-01-01

    When exhausting combustible hydrocarbon vapors form sea-going tankers, vapor recovery systems must be spark resistant and gas tight while maintaining stable operation over a wide flow range and minimizing noise, resisting corrosion and providing low maintenance. A {open_quotes}surgeless blower{close_quotes} has met these challenges in 17 US marine vapor emission control systems. The blower, which mounts on a dock, helps move vapors emitted during tanker loading from the tankers through long exhaust ducts to processing plants. The duct-work typically included valves, detonation arresters and other components that increase resistance to gas flow. The volume flow requirement of the exhaust system varies widely depending on the loading rate. A high-pressure blower is therefore needed to allow for a wide range of operating volumes-from 100 CFM to 13,000 CFM-without causing instability or surging. The materials used to construct blowers must be corrosion resistant on inside surfaces to withstand the corrosive effects of hydrocarbon vapor and outside surfaces to operate in the salt-spray environment of seaside docks.

  7. Modification and application of a leaf blower-vac for field sampling of arthropods

    NARCIS (Netherlands)

    Zou, Yi; Telgen, van Mario D.; Chen, Junhui; Xiao, Haijun; Kraker, de Joop; Bianchi, Felix J.J.A.; Werf, van der Wopke

    2016-01-01

    Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure,

  8. Coronary artery surgery without cardiopulmonary bypass: usefulness of the surgical blower-humidifier.

    Science.gov (United States)

    Maddaus, M; Ali, I S; Birnbaum, P L; Panos, A L; Salerno, T A

    1992-12-01

    Coronary artery bypass surgery can be performed without cardiopulmonary bypass (CPB). Bleeding obscuring the operative field and hemodilution of shed blood with irrigating saline are some of the drawbacks of this technique. We report the use of a newly developed surgical blower-humidifier (custom made [Research Medical, Inc.]) for improved visualization and facilitation of coronary artery surgery without CPB.

  9. 42 CFR 84.146 - Method of measuring the power and torque required to operate blowers.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Method of measuring the power and torque required... RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.146 Method of measuring the power and torque... blower, the drum is started in rotation manually at or slightly above the speed at which the...

  10. Densità di energia di deformazione locale e resistenza a fatica di giunti saldati di geometria complessa

    Directory of Open Access Journals (Sweden)

    P. Lazzarin

    2008-01-01

    Full Text Available Un recente criterio basato sul valore medio della densità di energia di deformazione (SED inun volume di controllo è applicato a diverse serie di dati sperimentali tratti dalla letteratura, relativi a giuntisaldati di geometria complessa realizzati in acciaio. Il volume di controllo è rappresentato da un settore circolare di raggio pari a 0.28 mm, centrato sul piede o sulla radice dei cordoni di saldatura. Entrambe le regioni sono modellate come intagli V non raccordati con differenti angoli di apertura. La densità di energia di deformazione viene valutata direttamente da modelli agli elementi finiti tridimensionali. I dati sperimentali, riconvertiti in termini energetici, si posizionano all’interno di una banda di dispersionerecentemente proposta in letteratura. La banda sintetizzava più di 650 dati sperimentali relativi a giunti saldati con cordone d’angolo, con rotture innescate indifferentemente al piede o alla radice dei cordonidi saldatura.

  11. Caminhos e percursos da Geometria Analítica: estudo histórico e epistemológico

    OpenAIRE

    Castro, Adriana

    2013-01-01

    A Geometria Analítica é parte integrante dos conteúdos a serem trabalhados na Educação Básica. Além disso, os conceitos trabalhados na Educação Básica são aprofundados nos componentes curriculares dos cursos de graduação das ciências exatas tais como Engenharia, Ciências da Computação, Arquitetura, Matemática, Física, etc. Seu estudo é relevante, pois é uma ferramenta importante para o Cálculo Diferencial e Integral e é uma das principais referências em um primeiro curso de Álgebra Linear. Es...

  12. Investigações em geometria via ambiente LOGO LOGO environment as an alternative methodological strategy to teach geometry

    Directory of Open Access Journals (Sweden)

    Raimundo Benedito do Nascimento

    2004-01-01

    Full Text Available A Matemática torna-se mais significativa para um aluno que está constantemente em contato com ampla variedade de problemas. Este artigo tem o objetivo de motivar o professor a não poupar esforços para estimular suas classes de Geometria com problemas que conduzam os alunos para além dos exercícios rotineiros. O ambiente LOGO é a estratégia metodológica alternativa que nos conduzirá ao objetivo proposto.Students find mathematics more significant if they are constantly in contact with a variety of problems. The purpose of this article is to motivate teachers to enhance their geometry classes with problems taken from the everyday lives of their students. The LOGO environment can be used as an alternative methodological strategy, providing problem situations.

  13. Machining of the Blower Shroud%静叶片座的加工

    Institute of Scientific and Technical Information of China (English)

    王林锋; 张雪萍

    2013-01-01

    静叶片(导风叶)座为6个弧段拼装而成,其外径达Φ2012 m m,加工后内径为Φ1804 m m,壁厚较薄(最薄厚度仅为20 m m),整个部件重量达到了2.6 T。静叶片装配通过橡胶压缩量进行撑紧,若装配补偿量不足,易导致导风叶松动,影响后续静叶片座的加工。同时,由于静叶片座壁厚较薄,加工易导致变形。文章通过改善静叶片装配与改变静叶片座加工装夹及吊运翻身方式来控制它的变形。%The blower shroud was composed of 6pcs of segment with outside diameter of¢2 012mm and machined inner diameter of¢1 804mm, being a thin wall thickness part (the thinnest thickness was only 20mm) and totaling 2.6T. The blower blade was held tightly depending on the rubber compression in this assembly. In case of that assem-bling compensation was not sufifcient, loosing of the blower blade would occur, thus, influencing the following proce-dure of the machining of the blower shroud. Meanwhile, deformation frequently happened after machining because of the thin wall of the blower shroud. Suggestions were pre-sented in the ifelds of improvement of the blade assembling, clamping way for machining process, machining method and hoisting/turning-over method, to control deformation during process.

  14. Jet noise suppression by porous plug nozzles

    Science.gov (United States)

    Bauer, A. B.; Kibens, V.; Wlezien, R. W.

    1982-01-01

    Jet noise suppression data presented earlier by Maestrello for porous plug nozzles were supplemented by the testing of a family of nozzles having an equivalent throat diameter of 11.77 cm. Two circular reference nozzles and eight plug nozzles having radius ratios of either 0.53 or 0.80 were tested at total pressure ratios of 1.60 to 4.00. Data were taken both with and without a forward motion or coannular flow jet, and some tests were made with a heated jet. Jet thrust was measured. The data were analyzed to show the effects of suppressor geometry on nozzle propulsive efficiency and jet noise. Aerodynamic testing of the nozzles was carried out in order to study the physical features that lead to the noise suppression. The aerodynamic flow phenomena were examined by the use of high speed shadowgraph cinematography, still shadowgraphs, extensive static pressure probe measurements, and two component laser Doppler velocimeter studies. The different measurement techniques correlated well with each other and demonstrated that the porous plug changes the shock cell structure of a standard nozzle into a series of smaller, periodic cell structures without strong shock waves. These structures become smaller in dimension and have reduced pressure variations as either the plug diameter or the porosity is increased, changes that also reduce the jet noise and decrease thrust efficiency.

  15. Design specifications for explosion protection blowers. Effects of the geometry of a radial blower on its dimensionless characteristics; Entwurfsanforderungen fuer Explosionsschutzventilatoren. Einfluss der geometrischen Konstruktionsgestaltungen eines Radialventilators auf seine dimensionslosen Kennzahlen

    Energy Technology Data Exchange (ETDEWEB)

    Prysok, E. [Forschungs- und Entwicklungszentrum Barowent, Katowice (Poland)

    2003-08-01

    Blowers transporting explosive mixtures of gases and vapours and/or explosive atmospheric dust require special safety measures. The contribution discusses general design principles for explosion protection blowers. [German] Ventilatoren, die zur Foerderung von explosionsfaehigen Gemischen brennbarer Gase und Daempfe sowie explosionsfaehiger Staeube in der Atmosphaere bestimmt sind, benoetigen die Anwendung entsprechender Sicherung fuer ihre Konstruktion. Im folgenden Beitrag werden allgemeine, Explosionsschutzventilatoren betreffende Konstruktionsprinzipien dargestellt. (orig.)

  16. Low flow rates and high air throughput: Cross-flow blowers; Niedrige Stroemungsgeschwindigkeiten bei hohem Luftdurchsatz: Querstromventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, J. [ebm-papst Landshut GmbH (Germany)

    2006-05-15

    Cross-flow blowers are everywhere, in electric towel driers, heaters, night storage heaters, floor heating systems, and open chimneys. With a diameter of only 30 mm, they are compact and effective. (orig.)

  17. Nuclear thermal rocket nozzle testing and evaluation program

    Science.gov (United States)

    Davidian, Kenneth O.; Kacynski, Kenneth J.

    1993-01-01

    Performance characteristics of the Nuclear Thermal Rocket can be enhanced through the use of unconventional nozzles as part of the propulsion system. The Nuclear Thermal Rocket nozzle testing and evaluation program being conducted at the NASA Lewis is outlined and the advantages of a plug nozzle are described. A facility description, experimental designs and schematics are given. Results of pretest performance analyses show that high nozzle performance can be attained despite substantial nozzle length reduction through the use of plug nozzles as compared to a convergent-divergent nozzle. Pretest measurement uncertainty analyses indicate that specific impulse values are expected to be within + or - 1.17 pct.

  18. Method of cooling gas only nozzle fuel tip

    Science.gov (United States)

    Bechtel, William Theodore; Fitts, David Orus; DeLeonardo, Guy Wayne

    2002-01-01

    A diffusion flame nozzle gas tip is provided to convert a dual fuel nozzle to a gas only nozzle. The nozle tip diverts compressor discharge air from the passage feeding the diffusion nozzle air swirl vanes to a region vacated by removal of the dual fuel components, so that the diverted compressor discharge air can flow to and through effusion holes in the end cap plate of the nozzle tip. In a preferred embodiment, the nozzle gas tip defines a cavity for receiving the compressor discharge air from a peripheral passage of the nozzle for flow through the effusion openings defined in the end cap plate.

  19. Integrated Composite Rocket Nozzle Extension Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop and demonstrate an Integrated Composite Rocket Nozzle Extension (ICRNE) for use in rocket thrust chambers. The ICRNE will utilize an...

  20. O ENSINO DE GEOMETRIA NAS SÉRIES INICIAIS DO ENSINO FUNDAMENTAL: ANALISANDO AS CONCEPÇÕES DOS ACADÊMICOS DO NORMAL SUPERIOR

    Directory of Open Access Journals (Sweden)

    Leny R. M. Teixeira

    2012-07-01

    Full Text Available O presente trabalho relata os resultados de um estudo que investigou concepções e dificuldades de acadêmicos do Curso Normal Superior da Universidade Católica Dom Bosco/Campo Grande-MS a respeito do ensino de Geometria nas séries iniciais do ensino fundamental. Os dados foram coletados mediante observações e aplicação de um questionário durante a realização de um minicurso que envolvia atividades relacionadas às formas tridimensionais e bidimensionais. O questionário tinha o propósito de identificar as concepções e dificuldades dos participantes a respeito da diferenciação entre sólidos e figuras planas. Os dados revelaram que as dificuldades dos acadêmicos, em Geometria, estão relacionadas tanto à nomeação e representação no plano de formas tridimensionais, como à diferenciação entre sólidos e figuras planas. Quanto às concepções, os acadêmicos apontam o livro didático como uma das principais alternativas para conduzir o ensino de Geometria

  1. Flow optimization in blowers by means of LDA measurements; Stroemungstechnische Optimierung von Ventilatoren mit Hilfe der LDA-Messtechnik

    Energy Technology Data Exchange (ETDEWEB)

    Reichert, E.; Strehle, M. [ebm Werke GmbH und Co. KG, Mulfingen (Germany); Bohl, K. [Heilbronn Fachhochschule (Germany)

    2003-06-01

    The contribution describes the application of LDA techniques for flow measurements and optimization of blowers. Three examples are presented to show how LDA measurements can be used for optimization and design of industrial blowers. [German] Der Beitrag beschreibt die Anwendung der LDA-Messtechnik fuer die stroemungstechnische Entwicklung und Optimierung von Ventilatoren. An drei Beispielen wird gezeigt, wie im industriellen Einsatz mit LDA-Messungen wesentliche Informationen ermittelt werden koennen, die dann zur Verbesserung oder zur Auslegung von Ventilatoren eingesetzt werden. (orig.)

  2. Design of a new type vapor recovery system nozzle

    Science.gov (United States)

    Fu, S. H.; Cao, G. J.; Zhang, D. S.

    2016-05-01

    To settle the problem of low-efficiency recovery for Vapor recovery system nozzle, this paper advances a purely mechanical structure of the self-sealing refueling VRS nozzle. The structure, operating principle and controlled process of the nozzle is given. And an application of the nozzle is discussed. All indicated that the nozzle has a reasonable structure, can fuel and vapor recovery simultaneous start and stop. And thus improve the recovery efficiency and reduce oil leakage.

  3. Hot Streak Characterization in Serpentine Exhaust Nozzles

    Science.gov (United States)

    2014-12-26

    55 3.1.5 Annular Area and Core Radius Calculations . . . . . . . . . . . . . 55 3.2 Nozzle Design...108 4.15 Grid Density at Nozzle Exit for Grid-Convergence Study . . . . . . . . . . . . 110 4.16 Grid Convergence Study Linearity Plots...engine spool. Thus, this type of duct can be considered an annular -to-rectangular transition. Prior research into the effect of this centerbody on

  4. Measurement and Analysis of the Noise Radiated by Low Mach Number Centrifugal Blowers.

    Science.gov (United States)

    Yeager, David Marvin

    An investigation was performed of the broad band, aerodynamically generated noise in low tip-speed Mach number, centrifugal air moving devices. An interdisciplinary experimental approach was taken which involved investigation of the aerodynamic and acoustic fields, and their mutual relationship. The noise generation process was studied using two experimental vehicles: (1) a scale model of a homologous family of centrifugal blowers typical of those used to cool computer and business equipment, and (2) a single blade from a centrifugal blower impeller placed in a known, controllable flow field. The radiation characteristics of the model blower were investigated by measuring the acoustic intensity distribution near the blower inlet and comparing it with the intensity near the inlet to an axial flow fan. Results showed that the centrifugal blower is a distributed, random noise source, unlike an axial fan which exhibited the effects of a coherent, interacting source distribution. Aerodynamic studies of the flow field in the inlet and at the discharge to the rotating impeller were used to assess the mean flow distribution through the impeller blade channels and to identify regions of excessive turbulence near the rotating blade row. Both circumferential and spanwise mean flow nonuniformities were identified along with a region of increased turbulence just downstream of the scroll cutoff. The fluid incidence angle, normally taken as an indicator of blower performance, was estimated from mean flow data as deviating considerably from an ideal impeller design. An investigation of the noise radiated from the single, isolated airfoil was performed using modern correlation and spectral analysis techniques. Radiation from the single blade in flow was characterized using newly developed expressions for the correlation area and the dipole source strength per unit area, and from the relationship between the blade surface pressure and the incident turbulent flow field. Results

  5. HyBlade sets new standards in axial blowers. Combination of metals and fibre-reinforced plastics; HyBlade setzt neue Massstaebe bei Axialventilatoren. Kombination von Metallen und faserverstaerkten Kunststoffen

    Energy Technology Data Exchange (ETDEWEB)

    Streng, G. [ebm-papst, Mulfingen (Germany)

    2008-03-15

    Motors with external rotors are common as a blower drives as the blower wheel can be mounted directly on the rotor. This simplifies blower construction and makes the blowers comparatively compact. This is an advantage not only in ari conditioning engineering where large blowers are commonly used, e.g. for passing air through heat exchangers. Demands on blowers are ever-increasing, i.e. maximum power, low noise, high efficiency, optimum corrosion protection, low weight, environmentally acceptable production technologies with a favourable energy balance, and - last but not least - an aesthetically pleasing design. (orig.)

  6. Análise Complexa e Geometria Diferencial de certas Superfícies do Espaço hiperbólico

    Directory of Open Access Journals (Sweden)

    Ricardo Sa Earp

    2003-11-01

    Full Text Available Desde os tempos de Gauss, Riemann e de outros que a GeometriaDiferencial entrelaça-se com a Análise Complexa. Um dos mais belos efeitos disto é a bem conhecida representação de Weierstrass para superfícies mínimas de R^3, consistindo de dados meromorfos (f,g que descrevem inteiramente uma tal superfície. O estudo da análise complexa aplicado neste contexto, ao longo das últimas décadas,tem produzido vertiginosos resultados e tem desenvolvido esta teoria para além das expectativas. Já é bem conhecido que as superfícies mínimas simplesmente conexas de R^3 pode-se associar suas primas no espaço hiperbólico tridimensional H^3 que possuem curvatura média igual a 1. Tal relação segue do teorema fundamental da Geometria, calcado nas equações de Gauss e de Codazzi-Mainardi. O fato é quetambém existem dados meromorfos sobre as superfícies de curvatura média 1 em H^3, o que sob um ponto de vista filosófico é de se esperar. Este é o escopo destas notas: Explicar um pouco as origens desta teoria e suas ligações com a teoria clássica das superfícies mínimas de R^3 e apresentar os dados meromorfos e exemplos, segundo um trabalho recente do autor com Toubiana. Como o espço hiperbólicopossui vários modelos naturais, diferentemente do espaço Euclideano, existem vários pontos de vistas alternativos nesta teoria revelando a riqueza inigualável da Geometria Hiperólica. Isto tem sido estabelecido por R. Bryant, Umehara,Yamada que são os pioneiros na moderna abordagem deste assunto. Notáveis trabalhos nesta área também têm sido compilados por Rossman, Small, Rosenberg, Collin, Hausswirth e Toubiana. De modo que fervilham resultados que exibem a pujança do link Análse Complexa, Geometria Hiperbólica & Geometria Diferencial.

  7. Impact of blower performance on residential forced-air heating system performance

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, B.G. [UNIES Ltd., Winnipeg, Manitoba (Canada)

    1998-10-01

    A Canadian association of electric utilities commissioned a study on Blower Efficiency in Domestic Heating Systems because furnace blowers have undesirable load characteristics for electrical utilities; their loads often peak coincident with utility system winter (heating) and summer (air-conditioning) peaks. The study examined air-handling technologies used in domestic furnaces, surveyed residential heating and cooling system installer practices, and measured air-handling performance of 71 existing forced-air heating systems installed between 1960 and 1994. This paper summarizes study findings, including changes in furnace airflows, static pressures, air-handling efficiencies, power requirements, and noise levels. It relates air-handling power requirements and airflows of new furnaces to furnace thermal efficiency.

  8. Boundary model-based reference control of blower cooled high temperature polymer electrolyte membrane fuel cells

    DEFF Research Database (Denmark)

    Jensen, Hans-Christian Becker; Kær, Søren Knudsen

    2011-01-01

    Fuel cells have, by design, a limited effective life time, which depends on how they are operated. The general consent is that operation of the fuel cell at the extreme of the operational range, or operation of the fuel cell without sufficient reactants (a.k.a. starvation), will lower the effective...... life time of a fuel cell significantly. On air cooled HTPEMFCs, the blower, which supplies the fuel cell with oxygen for the chemical process, also functions as the cooling system. This makes the blower bi-functional and as a result a higher supply of oxygen is often available, hence changes...... in the fuel cell output can be optimised by the knowledge of how much oxygen is supplied to the fuel cell at any given time, without reducing the effective life time of a fuel cell by starvation....

  9. Results from installation of waterlance soot blowers at Dairyland Power Cooperative`s JPM station

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D.L. [Dairyland Power Cooperative, La Crosse, WI (United States)

    1995-06-01

    Waterlance soot blowers were installed at the John P. Madgett (JPM) Station in 1992. Improvements in cleaning the furnace and wing wall areas have reduced furnace exit temperature, superheat and reheat sprays, the gas temperature entering the hot side precipitator and NO{sub x} emissions from the Boiler. Overall savings from the waterlances exceeds $11,000,000 in avoided costs and fuel savings. This paper discusses the installation and savings realized from the waterlances at the JPM station.

  10. Recognizing and avoiding wrong selections. Blowers in practice; Anwendungsfehler erkennen und vermeiden. Ventilatoren in der Praxis

    Energy Technology Data Exchange (ETDEWEB)

    Pielke, R.

    2002-02-01

    The contribution stresses that blower selection, i.e. design, material, integration in a system, drives and control units, should remain in the hand of experts. [German] Ventilatoren sind Stroemungsmaschinen zur Foerderung von Luft, die wir nicht sehen und fassen koennen. Die auf den Bedarfsfall zugeschnittene, optimale Auswahl eines Ventilators, die Klaerung der Materialfrage, die Einbindung des Ventilators in eine Anlage, die Festlegung des Antriebes sowie die erforderliche Regelung und Steuerung, das alles sind Fragen, die von einem Fachmann zu bearbeiten sind. (orig.)

  11. Blower burner market development. Boiler management by electronics; Ventilatorbrandermarkt in beweging. Elektronica maakt ketelmanagement mogelijk

    Energy Technology Data Exchange (ETDEWEB)

    Harms, R. [Monarch Nederland, Diemen (Netherlands)

    2004-09-01

    A brief overview is given of the developments in the market for blower burners. New technology concerns digital control techniques. [Dutch] De Nederlandse ventilatorbrandermarkt ondergaat de laatste jaren aanzienlijke wijzigingen. 25 jaar geleden trof men tientallen producenten en importeurs van gas-en oliebrandersnaar op een vakbeurs voor verwarming. Nu zijn er nog maar tien. Technische ontwikkelingen spelen zich op dit moment af op het terrein van de digitale besturingstechniek wat extra mogelijkheden biedt.

  12. Parametric study of solar thermal rocket nozzle performance

    Science.gov (United States)

    Pearson, J. Boise; Landrum, D. Brian; Hawk, Clark W.

    1995-01-01

    This paper details a numerical investigation of performance losses in low-thrust solar thermal rocket nozzles. The effects of nozzle geometry on three types of losses were studied; finite rate dissociation-recombination kinetic losses, two dimensional axisymmetric divergence losses, and compressible viscous boundary layer losses. Short nozzle lengths and supersonic flow produce short residence times in the nozzle and a nearly frozen flow, resulting in large kinetic losses. Variations in geometry have a minimal effect on kinetic losses. Divergence losses are relatively small, and careful shaping of the nozzle can nearly eliminate them. The boundary layer in these small nozzles can grow to a major fraction of nozzle radius, and cause large losses. These losses are attributed to viscous drag on the nozzle walls and flow blockage by the boundary layer, especially in the throat region. Careful shaping of the nozzle can produce a significant reduction in viscous losses.

  13. Nozzle assembly for an earth boring drill bit

    Energy Technology Data Exchange (ETDEWEB)

    Madigan, J. A.

    1985-09-24

    A nozzle assembly for an earth boring drill bit of the type adapted to receive drilling fluid under pressure and having a nozzle bore in the bottom thereof positioned closely adjacent the well bore bottom when the bit is in engagement therewith with the bore having inner and outer portions. The nozzle assembly comprises a generally cylindrical nozzle member of abrasion and erosion resistant material, selected from a plurality of such members, each being of the same outer diameter but having passaging therein of different cross-sectional area. The nozzle member is adapted to be fitted in the inner portion of the nozzle bore in sealing relationship therewith for forming a first seal for the nozzle assembly. The nozzle assembly further comprises a locknut, separate from the nozzle member, for detachbably securing the nozzle member in the nozzle bore, formed at least in part of an abrasion and erosion resistant material. The locknut has a threaded side wall engageable with the outer portion of the nozzle bore, and an aperture therethrough for enabling a stream of drilling fluid from the nozzle member to flow therethrough and being so configured in section as to receive a tool for turning the lockout to install it in and remove it from the nozzle bore.

  14. Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods

    Science.gov (United States)

    Zou, Yi; van Telgen, Mario D.; Chen, Junhui; Xiao, Haijun; de Kraker, Joop; Bianchi, Felix J. J. A.; van der Werf, Wopke

    2016-01-01

    Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure, application of this sampling device provides absolute estimates of the populations of arthropods as numbers per standardized sampling area. The sampling efficiency depends critically on the sampling duration. In a mature rice crop, a two-minute sampling in an enclosure of 0.13 m2 yields more than 90% of the arthropod population. The device also allows sampling of arthropods dwelling on the water surface or the soil in rice paddies, but it is not suitable for sampling fast flying insects, such as predatory Odonata or larger hymenopterous parasitoids. The modified blower-vac is simple to construct, and cheaper and easier to handle than traditional suction sampling devices, such as D-vac. The low cost makes the modified blower-vac also accessible to researchers in developing countries. PMID:27584040

  15. Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods.

    Science.gov (United States)

    Zou, Yi; van Telgen, Mario D; Chen, Junhui; Xiao, Haijun; de Kraker, Joop; Bianchi, Felix J J A; van der Werf, Wopke

    2016-08-10

    Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure, application of this sampling device provides absolute estimates of the populations of arthropods as numbers per standardized sampling area. The sampling efficiency depends critically on the sampling duration. In a mature rice crop, a two-minute sampling in an enclosure of 0.13 m(2) yields more than 90% of the arthropod population. The device also allows sampling of arthropods dwelling on the water surface or the soil in rice paddies, but it is not suitable for sampling fast flying insects, such as predatory Odonata or larger hymenopterous parasitoids. The modified blower-vac is simple to construct, and cheaper and easier to handle than traditional suction sampling devices, such as D-vac. The low cost makes the modified blower-vac also accessible to researchers in developing countries.

  16. Numerical Simulation of Unsteady Discharge Flow with Fluctuation in Positive Discharge Blower

    Institute of Scientific and Technical Information of China (English)

    LIU Zhengxian; WANG Dou; XU Lianhuan

    2009-01-01

    The operating performance of positive discharge blower/s markedly influenced by the pulsation of the discharge flow, but difficult to be measured with experimental methods. The internal and discharge flow of positive discharge blower with involute type three-lobe are numerically investigated, both in air cooling and countercurrent cooling conditions by means of computational fluid dynamics (CFD). The unsteady compressible flow equations are solved using RNG κ-ε turbulent model. The finite difference method and the second order upwind difference scheme are applied into discrete equations. In the numerical simulation, the dynamic mesh techniques are used to approach the rotating displacement of cell cubage and the alterability of inlet, outlet flow area. The non-uniform mesh is applied to the rotor-stator coupled area. The reliability of the numerical method is verified by simulating the inner flow and comparing with the semi-empirical theory. The flow flux curves and the distributing of velocity vector showed obvious vortex motion in all the discharge process, both in air cooling and countercurrent cooling conditions. These vortexes with different positions, intension and numbers at different rotating angles have remarkable influences on the discharge flux. For air cooling, the vortex produced a second pulsation with big-amplitude in a cycle, and led to the early appearance of maximum of backflow. For countercurrent cooling, the frequency of pulsation increased due to the pre-inflow, but the hackflow at the outlet is prevented, also the pulsation strength has greatly decreased.

  17. An analytical model to describe the compression in turbomolecular pumps and roots blowers

    Energy Technology Data Exchange (ETDEWEB)

    Voss, G [Oerlikon Leybold Vacuum Bonner Str. 498, D - 50968 Cologne (Germany)], E-mail: gerhard.voss@oerlikon.com

    2008-05-01

    An analytical model is presented, useful in practice, for calculating and analysing the compression curves of classical turbomolecular pumps, wide range turbomolecular pumps and Roots blowers. It is demonstrated that the model, primarily proposed for classical turbomolecular pumps, can be applied to wide range turbomolecular pumps and Roots blowers as well. The model is based on an ordinary differential equation for the pressure as a function of position inside the pump. Solving the differential equation makes it possible both to calculate the compression curves for a finite gas throughput (Q > 0) and for zero gas throughput. A hypothesis is posed holding that the compression curve for zero gas throughput can be derived from a compression curve for a finite gas throughput, e.g., Q = 1 sccm in the case of turbomolecular pumps. In the case of Roots blowers a proposal is made how to describe the backleakage phenomenon quantitatively. For each type of vacuum pump mentioned above the comparison with experimental data shows that the model provides an excellent qualitative and quantitative reproduction of the observed phenomena in the whole relevant pressure range, i.e., perfect agreement over more than five pressure decades is achieved.

  18. Deficiencies in building envelope performance. Quantitative results with blower-door and thermography

    Energy Technology Data Exchange (ETDEWEB)

    Popp, G.; Kalender, V.; Heidt, F.D. [Dept. of Physics, Univ. of Siegen (Germany)

    1996-12-31

    Air-tightness and lack of thermal bridges are indispensable characteristics of low energy houses and passive solar buildings. Although the German heating demand regulation (Waermeschutzverordnung) does not require a verification as yet, only measurements can give the proof of assured quality. Blower doors are well suited to test the air-tightness of buildings and thermographic records can identify and visualize thermal bridges. A new software-tool was developed to evaluate blower door measurements in accordance with the prescriptions of ISO 9972. Further, a new control of pressure differences across blower doors was developed to enable precise air flow measurements through single, small leakages in low-energy buildings by the balanced fan pressurization method. For quantitative analysis of thermographic pictures an evaluation software package was developed including an algorithm to determine lengths and surface areas of objects. Based on various assumptions and boundary conditions it is possible to determine the relative deviations of local U-values from their mean value. Measurements were carried out at 39 buildings of several construction techniques. Typical examples of commonly occuring thermal bridges and air leakages are rolling shutter boxes, window and floor joints as well as wall sockets. The total heat loss through thermal bridges can be reduced by up to 15% - as shown in simulations - with only few constructive measures. (orig.)

  19. Near-fatal methemoglobinemia after recreational inhalation of amyl nitrite aerosolized with a compressed gas blower.

    Science.gov (United States)

    Lin, Chih-Hao; Fang, Cheng-Chung; Lee, Chien-Chang; Ko, Patrick Chow-In; Chen, Wen-Jone

    2005-11-01

    Adverse effects associated with recreational inhalation of nitrites are usually mild and rarely life-threatening. We report a rare case of near-fatal methemoglobinemia after inhalation of amyl nitrite after aerosolizing the liquid using a compressed gas blower designed to clean photographic equipment that employed hydrofluoroalkane-134a as a propellant. A 31-year-old previously healthy male became dyspneic and fainted soon after the recreational inhalation of amyl nitrite aerosolized using a compressed gas blower. He was brought to the emergency department with severe cyanotic appearance and profound shock. Oxygen saturation was 82%, unresponsive to oxygen supply. His methemoglobin blood level was 52.2%. After 100 mg of methylene blue (2 mg/kg body weight) was administered intravenously, he recovered consciousness, and dyspnea and cyanosis subsided gradually. This case illustrates the extraordinary hazard of the use of a compressed gas blower in the recreational inhalation of nitrites. Prompt recognition and rapid antidotal treatment may adequately correct near-fatal overdose associated with recreational use of amyl nitrite.

  20. Upper Stage Engine Composite Nozzle Extensions

    Science.gov (United States)

    Valentine, Peter G.; Allen, Lee R.; Gradl, Paul R.; Greene, Sandra E.; Sullivan, Brian J.; Weller, Leslie J.; Koenig, John R.; Cuneo, Jacques C.; Thompson, James; Brown, Aaron; Shigley, John K.; Dovey, Henry N.; Roberts, Robert K.

    2015-01-01

    Carbon-carbon (C-C) composite nozzle extensions are of interest for use on a variety of launch vehicle upper stage engines and in-space propulsion systems. The C-C nozzle extension technology and test capabilities being developed are intended to support National Aeronautics and Space Administration (NASA) and United States Air Force (USAF) requirements, as well as broader industry needs. Recent and on-going efforts at the Marshall Space Flight Center (MSFC) are aimed at both (a) further developing the technology and databases for nozzle extensions fabricated from specific CC materials, and (b) developing and demonstrating low-cost capabilities for testing composite nozzle extensions. At present, materials development work is concentrating on developing a database for lyocell-based C-C that can be used for upper stage engine nozzle extension design, modeling, and analysis efforts. Lyocell-based C-C behaves in a manner similar to rayon-based CC, but does not have the environmental issues associated with the use of rayon. Future work will also further investigate technology and database gaps and needs for more-established polyacrylonitrile- (PAN-) based C-C's. As a low-cost means of being able to rapidly test and screen nozzle extension materials and structures, MSFC has recently established and demonstrated a test rig at MSFC's Test Stand (TS) 115 for testing subscale nozzle extensions with 3.5-inch inside diameters at the attachment plane. Test durations of up to 120 seconds have been demonstrated using oxygen/hydrogen propellants. Other propellant combinations, including the use of hydrocarbon fuels, can be used if desired. Another test capability being developed will allow the testing of larger nozzle extensions (13.5- inch inside diameters at the attachment plane) in environments more similar to those of actual oxygen/hydrogen upper stage engines. Two C-C nozzle extensions (one lyocell-based, one PAN-based) have been fabricated for testing with the larger

  1. Compressible vortex loops: Effect of nozzle geometry

    Energy Technology Data Exchange (ETDEWEB)

    Zare-Behtash, H. [School of MACE, University of Manchester, M60 1QD (United Kingdom)], E-mail: h.zare-behtash@postgrad.manchester.ac.uk; Kontis, K. [School of MACE, University of Manchester, M60 1QD (United Kingdom)], E-mail: k.kontis@manchester.ac.uk; Gongora-Orozco, N. [School of MACE, University of Manchester, M60 1QD (United Kingdom); Takayama, K. [Tohoku University, Shock Wave Research Centre, Sendai 980-8577 (Japan)

    2009-06-15

    Vortex loops are fundamental building blocks of supersonic free jets. Isolating them allows for an easier study and better understanding of such flows. The present study looks at the behaviour of compressible vortex loops of different shapes, generated due to the diffraction of a shock wave from a shock tube with different exit nozzle geometries. These include a 15 mm diameter circular nozzle, two elliptical nozzles with minor to major axis ratios of 0.4 and 0.6, a 30 x 30 mm square nozzle, and finally two exotic nozzles resembling a pair of lips with minor to major axis ratios of 0.2 and 0.5. The experiments were performed for diaphragm pressure ratios of P{sub 4}/P{sub 1}=4, 8, and 12, with P{sub 4} and P{sub 1} being the pressures within the high pressure and low pressure compartments of the shock tube, respectively. High-speed schlieren photography as well as PIV measurements of both stream-wise and head-on flows have been conducted.

  2. New inlet nozzle assembly: C Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Calkin, J.F.

    1960-10-19

    The use of self-supported fuel elements in ribless Zircaloy-2 tubes at C-Reactor requires some inlet nozzle modification to allow charging of the larger overall diameter fuel pieces. A new nozzle assembly has been developed (by Equipment Development Operation -- IPD) which will allow use of the new fuel pieces and at the same time increase the reliability of the header-to-tube piping and reduce pumping power losses. Flow test data were requested for the new assembly and the results of these tests are presented herein. This report also presents a comparison of the header to tube energy losses for the various reactor inlet nozzle assemblies which are currently used on the Hanford production reactors.

  3. Discharge coefficient of small sonic nozzles

    Directory of Open Access Journals (Sweden)

    Yin Zhao-Qin

    2014-01-01

    Full Text Available The purpose of this investigation is to understand flow characteristics in mini/micro sonic nozzles, in order to precisely measure and control miniscule flowrates. Experimental and numerical simulation methods have been used to study critical flow Venturi nozzles. The results show that the nozzle’s size and shape influence gas flow characteristics which leading the boundary layer thickness to change, and then impact on the discharge coefficient. With the diameter of sonic nozzle throat decreasing, the discharge coefficient reduces. The maximum discharge coefficient exits in the condition of the inlet surface radius being double the throat diameter. The longer the diffuser section, the smaller the discharge coefficient becomes. Diffuser angle affects the discharge coefficient slightly.

  4. A GEOMETRIA SE CONSTITUINDO PRÉ-REFLEXIVAMENTE: PROPOSTAS. GEOMETRY CONSTITUTING ITSELF IN A PRE-REFLEXIVE WAY: PROPOSALS

    Directory of Open Access Journals (Sweden)

    Adlai Ralph Detoni

    2012-11-01

    Full Text Available Este texto traz propostas de atividades didáticas em torno de temas pertinentes à Geometria Escolar para os anos iniciais do ensino fundamental que foram inicialmente trabalhadas em pesquisa de campo para estudos de doutoramento, cujos dados foram tratados metodologicamente na abordagem qualitativa fenomenológica. Faz-se uma exposição filosófica que sustenta uma concepção fenomenológica do espaço e reflexões de seu desdobramento para um pensamento pedagógico que valoriza o conhecimento constituído no domínio do pré-reflexivo.This text brings proposals of didactic activities on themes that are connected to Geometry in the initial years of elementary school and which were initially developed in field research for doctoring studies that methodologically treated the data in a qualitative phenomenological approach. A philosophical exposition is presented and it supports a phenomenological conception of space and reflections on its unfolding into a pedagogical thinking that valorizes the knowledge constituted in the pre-reflexive domain.

  5. A geometria do campo magnético na região da nuvem Lupus 1

    Science.gov (United States)

    Alves, F. P.; Franco, G. A. P.

    2003-08-01

    Apresentaremos os resultados de uma investigação polarimétrica na região de formação estelar junto à nuvem escura Lupus 1. Esse estudo baseia-se em polarimétria CCD obtida na banda R, e cobre Lupus 1, bem como a área vizinha a essa nuvem contendo a cavidade em 100 mm IRAS. Os dados observacionais foram coletados com o telescópio IAG de 60 cm do Observatório do Pico dos Dias (LNA/MCT - Brasópolis - MG). Nossa primeira análise mostra que uma variação da orientação do campo magnético através da região pode produzir padrões complexos de polarização cuja geometria do campo não pode ser facilmente determinada. Os padrões de polarização são inconsistentes com um campo magnético estritamente uniforme e unidimensional em larga escala. Comparação com a emissão em 100 mm mostra que localmente os vetores de polarização exibem um forte alinhamento com a orientação dos padrões observados em infravermelho.

  6. Biannular Airbreathing Nozzle Rig (BANR) facility checkout and plug nozzle performance test data

    Science.gov (United States)

    Cummings, Chase B.

    2010-09-01

    The motivation for development of a supersonic business jet (SSBJ) platform lies in its ability to create a paradigm shift in the speed and reach of commercial, private, and government travel. A full understanding of the performance capabilities of exhaust nozzle configurations intended for use in potential SSBJ propulsion systems is critical to the design of an aircraft of this type. Purdue University's newly operational Biannular Airbreathing Nozzle Rig (BANR) is a highly capable facility devoted to the testing of subscale nozzles of this type. The high accuracy, six-axis force measurement system and complementary mass flowrate measurement capabilities of the BANR facility make it rather ideally suited for exhaust nozzle performance appraisal. Detailed accounts pertaining to methods utilized in the proper checkout of these diagnostic capabilities are contained herein. Efforts to quantify uncertainties associated with critical BANR test measurements are recounted, as well. Results of a second hot-fire test campaign of a subscale Gulfstream Aerospace Corporation (GAC) axisymmetric, shrouded plug nozzle are presented. Determined test article performance parameters (nozzle thrust efficiencies and discharge coefficients) are compared to those of a previous test campaign and numerical simulations of the experimental set-up. Recently acquired data is compared to published findings pertaining to plug nozzle experiments of similar scale and operating range. Suggestions relating to the future advancement and improvement of the BANR facility are provided. Lessons learned with regards to test operations and calibration procedures are divulged in an attempt to aid future facility users, as well.

  7. Lightweight Nozzle Extension for Liquid Rocket Engines Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The ARES J-2X requires a large nozzle extension. Currently, a metallic nozzle extension is being considered with carbon-carbon composite as a backup. In Phase 1,...

  8. Noise of Embedded High Aspect Ratio Nozzles

    Science.gov (United States)

    Bridges, James E.

    2011-01-01

    A family of high aspect ratio nozzles were designed to provide a parametric database of canonical embedded propulsion concepts. Nozzle throat geometries with aspect ratios of 2:1, 4:1, and 8:1 were chosen, all with convergent nozzle areas. The transition from the typical round duct to the rectangular nozzle was designed very carefully to produce a flow at the nozzle exit that was uniform and free from swirl. Once the basic rectangular nozzles were designed, external features common to embedded propulsion systems were added: extended lower lip (a.k.a. bevel, aft deck), differing sidewalls, and chevrons. For the latter detailed Reynolds-averaged Navier-Stokes (RANS) computational fluid dynamics (CFD) simulations were made to predict the thrust performance and to optimize parameters such as bevel length, and chevron penetration and azimuthal curvature. Seventeen of these nozzles were fabricated at a scale providing a 2.13 inch diameter equivalent area throat." ! The seventeen nozzles were tested for far-field noise and a few data were presented here on the effect of aspect ratio, bevel length, and chevron count and penetration. The sound field of the 2:1 aspect ratio rectangular jet was very nearly axisymmetric, but the 4:1 and 8:1 were not, the noise on their minor axes being louder than the major axes. Adding bevel length increased the noise of these nozzles, especially on their minor axes, both toward the long and short sides of the beveled nozzle. Chevrons were only added to the 2:1 rectangular jet. Adding 4 chevrons per wide side produced some decrease at aft angles, but increased the high frequency noise at right angles to the jet flow. This trend increased with increasing chevron penetration. Doubling the number of chevrons while maintaining their penetration decreased these effects. Empirical models of the parametric effect of these nozzles were constructed and quantify the trends stated above." Because it is the objective of the Supersonics Project that

  9. Internal performance characteristics of vectored axisymmetric ejector nozzles

    Science.gov (United States)

    Lamb, Milton

    1993-01-01

    A series of vectoring axisymmetric ejector nozzles were designed and experimentally tested for internal performance and pumping characteristics at NASA-Langley Research Center. These ejector nozzles used convergent-divergent nozzles as the primary nozzles. The model geometric variables investigated were primary nozzle throat area, primary nozzle expansion ratio, effective ejector expansion ratio (ratio of shroud exit area to primary nozzle throat area), ratio of minimum ejector area to primary nozzle throat area, ratio of ejector upper slot height to lower slot height (measured on the vertical centerline), and thrust vector angle. The primary nozzle pressure ratio was varied from 2.0 to 10.0 depending upon primary nozzle throat area. The corrected ejector-to-primary nozzle weight-flow ratio was varied from 0 (no secondary flow) to approximately 0.21 (21 percent of primary weight-flow rate) depending on ejector nozzle configuration. In addition to the internal performance and pumping characteristics, static pressures were obtained on the shroud walls.

  10. Integrated Ceramic Matrix Composite and Carbon/Carbon Structures for Large Rocket Engine Nozzles and Nozzle Extensions Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Low-cost access to space demands durable, cost-effective, efficient, and low-weight propulsion systems. Key components include rocket engine nozzles and nozzle...

  11. Microalgal cell disruption via ultrasonic nozzle spraying.

    Science.gov (United States)

    Wang, M; Yuan, W

    2015-01-01

    The objective of this study was to understand the effect of operating parameters, including ultrasound amplitude, spraying pressure, nozzle orifice diameter, and initial cell concentration on microalgal cell disruption and lipid extraction in an ultrasonic nozzle spraying system (UNSS). Two algal species including Scenedesmus dimorphus and Nannochloropsis oculata were evaluated. Experimental results demonstrated that the UNSS was effective in the disruption of microalgal cells indicated by significant changes in cell concentration and Nile red-stained lipid fluorescence density between all treatments and the control. It was found that increasing ultrasound amplitude generally enhanced cell disruption and lipid recovery although excessive input energy was not necessary for best results. The effect of spraying pressure and nozzle orifice diameter on cell disruption and lipid recovery was believed to be dependent on the competition between ultrasound-induced cavitation and spraying-generated shear forces. Optimal cell disruption was not always achieved at the highest spraying pressure or biggest nozzle orifice diameter; instead, they appeared at moderate levels depending on the algal strain and specific settings. Increasing initial algal cell concentration significantly reduced cell disruption efficiency. In all UNSS treatments, the effectiveness of cell disruption and lipid recovery was found to be dependent on the algal species treated.

  12. Shock wave fabricated ceramic-metal nozzles

    NARCIS (Netherlands)

    Carton, E.P.; Stuivinga, M.E.C.; Keizers, H.L.J.; Verbeek, H.J.; Put, P.J. van der

    1999-01-01

    Shock compaction was used in the fabrication of high temperature ceramic-based materials. The materials' development was geared towards the fabrication of nozzles for rocket engines using solid propellants, for which the following metal-ceramic (cermet) materials were fabricated and tested: B4C-Ti (

  13. Fabrication of Microglass Nozzle for Microdroplet Jetting

    Directory of Open Access Journals (Sweden)

    Dan Xie

    2015-02-01

    Full Text Available An ejection aperture nozzle is the essential part for all microdrop generation techniques. The diameter size, the flow channel geometry, and fluid impedance are the key factors affecting the ejection capacity. A novel low-cost fabrication method of microglass nozzle involving four steps is developed in this work. In the first heating step, the glass pipette is melted and pulled. Then, the second heating step is to determine the tip cone angle and modify the flow channel geometry. The desired included angle is usually of 30~45 degrees. Fine grind can determine the exact diameter of the hole. Postheating step is the final process and it can reduce the sharpness of the edges of the hole. Micronozzles with hole diameters varying from 30 to 100 µm are fabricated by the homemade inexpensive and easy-to-operate setup. Hydrophobic treating method of microglass nozzle to ensure stable and accurate injection is also introduced in this work. According to the jetting results of aqueous solution, UV curing adhesive, and solder, the fabricated microglass nozzle can satisfy the need of microdroplet jetting of multimaterials.

  14. New atomization nozzle for spray drying

    NARCIS (Netherlands)

    Deventer, H.C. van; Houben, R.J.; Koldeweij, R.B.J.

    2013-01-01

    A new atomization nozzle based on ink jet technology is introduced for spray drying. Application areas are the food and dairy industry, in the first instance, because in these industries the quality demands on the final powders are high with respect to heat load, powder shape, and size distribution.

  15. Aggregate breakup in a contracting nozzle.

    Science.gov (United States)

    Soos, Miroslav; Ehrl, Lyonel; Bäbler, Matthäus U; Morbidelli, Massimo

    2010-01-05

    The breakup of dense aggregates in an extensional flow was investigated experimentally. The flow was realized by pumping the suspension containing the aggregates through a contracting nozzle. Variation of the cluster mass distribution during the breakage process was measured by small-angle light scattering. Because of the large size of primary particles and the dense aggregate structure image analysis was used to determine the shape and structure of the produced fragments. It was found, that neither aggregate structure, characterized by a fractal dimension d(f) = 2.7, nor shape, characterized by an average aspect ratio equal to 1.5, was affected by breakage. Several passes through the nozzle were required to reach the steady state. This is explained by the radial variation of the hydrodynamic stresses at the nozzle entrance, characterized through computational fluid dynamics, which implies that only the fraction of aggregates whose strength is smaller than the local hydrodynamic stress is broken during one pass through the nozzle. Scaling of the steady-state aggregate size as a function of the hydrodynamic stress was used to determine the aggregate strength.

  16. Tecnologias digitais na sala de aula para aprendizagem de conceitos de geometria analítica: manipulações no software GrafEq

    OpenAIRE

    Ricardo de Souza Santos

    2008-01-01

    Este estudo aborda a utilização de recursos disponibilizados pelas tecnologias digitais no ensino-aprendizagem de Matemática. Mais especificamente, o objeto de estudo é a introdução do software GrafEq no ensino de Geometria Analítica no Ensino Médio da Escola Básica, com reflexões acerca das contribuições identificadas. Para verificar o alcance destas contribuições, foi implantada uma sequência de atividades em duas turmas do segundo ano do nível médio em uma escola da rede privada de Porto A...

  17. Preventing resonance problems in speed-controlled blowers. Destruction of the blower-motor unit may result; Resonanzprobleme drehzahlgeregelter Ventilatoren vermeiden. Zerstoerung der Ventilator-Motoreinheit nicht ausgeschlossen

    Energy Technology Data Exchange (ETDEWEB)

    Lexis, J.

    2004-05-01

    The economic efficiency of a ventilation depends not least on the ease with which air volumes can be adapted to changing operating conditions. Speed control is the most common method, but undesired resonance phenomena may occur in certain operating conditions. This must be prevented at all cost as resonances will cause noise problems and may even destroy the blower-motor unit. (orig.) [German] Die Wirtschaftlichkeit einer lufttechnischen Anlage wird entscheidend dadurch bestimmt, wie gut oder wie schlecht sich die Anpassung der Luftmengen an veraenderte Betriebssituationen realisieren laesst. Die am haeufigsten verwendete Methode ist die Drehzahlregelung des Ventilators. Dabei kann es unter bestimmten Betriebsbedingungen zu unerwuenschten Resonanzerscheinungen kommen. Der Betrieb eines Ventilators in diesem Bereich ist aber auf keinen Fall zulaessig, denn Resonanzen koennen zu Geraeuschproblemen und zur Zerstoerung der Ventilator-Motoreinheit fuehren. (orig.)

  18. A method of forecasting wide band noise in axial blowers. Part 2; Prognoseverfahren fuer den Breitbandlaerm bei Axialventilatoren. Teil 2

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M.; Carolus, T. [Siegen Univ. (Germany). Inst. fuer Fluid- und Thermodynamik

    2003-05-01

    Apart from the aerodynamic data of blowers, their acoustic properties are gaining importance. In industrial practice, blower noise is commonly estimated by very simple methods which only take account of very basic machine parameters. On the other hand, many semi-empirical models have been published for calculating blower noise which require more detailed input parameters, e.g. the velocity field around the blades, boundary layer parameters, etc. These models promise to be more accurate than the simple methods. [German] Neben den aerodynamischen Daten gewinnt die Schallleistung von Ventilatoren in zunehmendem Masse an Bedeutung. In der industriellen Praxis wird das Ventilatorgeraeusch bislang mit sehr einfachen Verfahren abgeschaetzt, die nur grundlegende Maschinengroessen beruecksichtigen. In der Literatur findet man allerdings eine Vielzahl semi-empirischer Modelle fuer die Schallleistungsberechnung von Ventilatoren, die detailliertere Eingangsparameter wie das Geschwindigkeitsfeld um die Schaufeln, Grenzschichtparameter usw. erfordern. Diese Modelle versprechen eine bessere Schallprognose als die einfachen Verfahren. (orig.)

  19. Theoretical model with experimental validation of a regenerative blower for hydrogen recirculation in a PEM fuel cell system

    Energy Technology Data Exchange (ETDEWEB)

    Badami, M.; Mura, M. [Dipartimento di Energetica, Politecnico di Torino, C.so Duca degli Abruzzi 24, Torino (Italy)

    2010-03-15

    A theoretical model of a regenerative blower used for the hydrogen recirculation of a Proton Exchange Membrane (PEM) fuel cell (FC) for automotive applications has been implemented and validated by means of experimental data. A momentum exchange theory was used to determine the head-flow rate curves, whereas the circulatory flow rate was determined through a theory based on the consideration of the centrifugal force field in the side channel and in the impeller vane grooves. The model allows a good forecast to be made of the blower behaviour, and only needs its main geometrical characteristics and some fluid-dynamic data as input. For this reason, the model could be very interesting, especially during the first sizing and the design activity of the blower. (author)

  20. Intermediate blades in slow radial blowers. Final report; Zwischenschaufeln - Zwischenschaufeln in langsamlaeufigen Radialventilatoren. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Carolus, T.; Basile, R.

    2001-05-01

    The effects of intermediate blades on the aerodynamic characteristics of slow radial blowers was investigated. It was found that the installation of intermediate blades of optimized design will slightly raise the pressure coefficients at comparable performance, especially if the initial number of blades was low. Stall will be reduced as well. On the basis of extensive investigations, a design diagram was drawn up which enables producers of blowers to assess the optimal intermediate blade configuration for a given blower quickly and easily. (orig.) [German] Der Einfluss von Zwischenschaufeln auf die aerodynamischen Kennwerte langsamlaeufiger Radialventilatorlaufraeder mit rueckwaertsgekruemmten Schaufeln wurde untersucht. Als Einflussparameter wurden die Hauptschaufelzahl, der Schaufelwinkel, das Breitenverhaeltnis, das Durchmesserverhaeltnis und die Zwischenschaufellaenge und -position in Betracht gezogen. Um eine moeglichst umfassende Bewertung dieser Zwischenschaufeln zu erhalten, wurden fuer eine Vielzahl von Parameterkombinationen die Stromfelder numerisch berechnet und daraus die aerodynamischen Kennwerte ermittelt. Dazu wurden zunaechst verschiedene Rechenverfahren und Rechenraumgrenzen untersucht und anhand von Messungen und Plausibilitaetsbetrachtungen bewertet. Als taugliches Rechenverfahren erwies sich ein dreidimensionales Navier-Stokes-Verfahren mit einem Rechenraum, der Einlaufduese, Radialspalt, Saugmund und Schaufelkanal umfasst. Die Ergebnisse systematischer Variationen der Einflussparameter zeigen, dass die aerodynamischen Kennwerte von allen oben genannten Parametern abhaengen. Der Einbau optimal ausgefuehrter Zwischenschaufeln in ein Ausgangsrad ohne Zwischenschaufeln fuehrt zu einer - wenn auch moderaten - Steigerung der Druckzahlen bei vergleichbaren Wirkungsgraden, insbesondere bei niedriger Hauptschaufelzahl des Ausgangsrades. Eine Minderung der Versperrung (d.h. eine Reduktion der Volumenzahl) ist mit Zwischenschaufeln moeglich. Mit den

  1. Gas blower for use in potentially explosive atmosphere; Ventilatoren fuer den Einsatz in explosionsgefaehrdeten Bereichen

    Energy Technology Data Exchange (ETDEWEB)

    Frobese, D.-H.; Waldmann, R.

    1996-12-31

    The extension of emission control requirements during the last years lead to an increasing demand for blowers suited for the transport of explosive waste gas. Concerning hazardous explosive atmosphere which is classified as zone 1 or zone 2, the ``VDMA-Einheitsblaetter`` give guidance to appropriate constructional requirements for blowers. However, for zone 0-applications, there do not exist fixed construction requirements up til now. In the range of validity of the ``Verordnung fuer brennbare Fluessigkeiten - VbF`` a type approval is requested for blowers to be used for zone 0. Equipment intended for use in potentially explosive atmospheres will fall under the new Directive 94/9/EC (explosion protection directive) in future; equipment to be used for zone 0 will need an EC-type-examination certificate which shall be issued by a notified body in accordance to the Directive. (orig.) [Deutsch] Die zunehmende Erfassung von Anlagen durch emissionsrechtliche Anforderungen hat in den letzten Jahren zu einem immer groesseren Bedarf an Ventilatoren zur Foerderung von explosionsfaehiger Abluft gefuehrt. Fuer den Einsatz in explosionsgefaehrdeten Bereichen der Zonen 1 und 2 gelten VDMA-Einheitsblaetter, nach denen Ventilatoren konstruiert werden koennen; fuer den Einsatz im Bereich der Zone 0 hingegen existieren bislang keine festgelegten Konstruktionsanforderungen. Im Geltungsbereich der Verordnung ueber brennbare Fluessigkeiten (VbF) wird fuer den Einsatz in Zone 0 eine Bauartzulassung gefordert. Zukuenftig unterliegen Geraete, die in explosionsgefaehrdeten Bereichen eingesetzt werden, der neuen EG-Richtlinie 94/9/EG (Explosionsschutzrichtlinie), wonach fuer Geraete, die in Zone 0 eingesetzt werden, eine Baumusterpruefbescheinigung einer benannten Zertifizierstelle erforderlich ist. (orig.)

  2. 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.

  3. Use of EC-blowers contribute to green investment; Gebruik van EC-ventilatoren levert bijdrage aan groene investering

    Energy Technology Data Exchange (ETDEWEB)

    Huijgens, G.; Ridder, A.

    2009-07-01

    Despite their small share in the entire use, applying EC blowers (electronically commutated) in coolers and condensers can provide an interesting contribution to a sound green investment. This additional investment with EC blowers will pay off through more efficient energy use and easy operation with rpm control. [Dutch] Door gebruik te maken van EC-ventilatoren (EC staat voor 'electronically commutated') op koelers en condensors kan, ondanks het kleine aandeel in het totaalverbruik, toch een interessante bijdrage geleverd worden aan een verantwoorde groene investering. Deze meerinvestering met EC-ventilatoren betaalt zich uit in zuinig energieverbruik en eenvoudige aansturing met toerenregeling.

  4. 罗茨鼓风机设计结构探讨%Discussion of Design Construction for Roots Blower

    Institute of Scientific and Technical Information of China (English)

    冯育棠; 杨光; 李文英

    2001-01-01

    Comparative discussion is done for the design construction of various types of Roots blowers.Advantages & shortcomings are pointed out.The constructive feature of series SL three lobe Roots blower is mainly introduced.%对各种类型的罗茨鼓风机的设计结构做了对比性的探讨,指出了其优缺点。重点介绍了SL系列三叶罗茨鼓风机的结构特点。

  5. In-cylinder gas velocity measurements comparing crankcase and blower scavenging in a fired two-stroke cycle engine

    Science.gov (United States)

    Miles, P. C.; Green, R. M.; Witze, P. O.

    1994-01-01

    The in-cylinder flow field of a Schnuerle (loop) scavenged two-stroke engine has been examined under conditions simulating both blower and crankcase driven scavenging. Measurements of the radial component of velocity were obtained along the cylinder centerline during fired operation at delivery ratios of 0.4, 0.6, and 0.8. Both mean velocity profiles and root mean square velocity fluctuations near top center show a strong dependence on the scavenging method. Complementary in-cylinder pressure measurements indicate that combustion performance is better under blower driven scavenging for the engine geometry studied.

  6. When Whistle-blowers Become the Story: The Problem of the ‘Third Victim’

    Science.gov (United States)

    Waring, Justin

    2016-01-01

    In the healthcare context, whistleblowing has come to the fore of political, professional and public attention in the wake of major service scandals and mounting evidence of the routine threats to safety that patients face in their care. This paper offers a commentary and wider contextualisation of Mannion and Davies, ‘Cultures of silence and cultures of voice: the role of whistleblowing in healthcare organisations.’ It argues that closer attention is needed to the way in which whistle-blowers can become the focus and victim of raising concerns and speaking up. PMID:26927403

  7. Damage to soot blowers in a high-dust DENOX plant

    Energy Technology Data Exchange (ETDEWEB)

    Bolte, C.; Farwick, H. (STEAG-RWE OHG, Voerde (Germany). Voerde Power Plant)

    1993-06-01

    The two 710 MW Units A and B at Voerde are equipped with selective catalytic reduction reactors in the high dust range. Following commissioning of the DENOX plant, the prescribed soot blowing conditions were proven to be adequate. About nine months later, the first operating problems occurred on the soot blowers and these intensified in the course of time. Following the failure of several steam supply pipes, the soot blowing then had to be adjusted to two-way since leaky blast valves became permeable to the condensate and dampening of the catalyser had to be feared. 2 refs., 9 figs.

  8. The blower characteristic. What information does it provide?; Die Ventilator-Kennlinie. Welche Informationen bietet sie?

    Energy Technology Data Exchange (ETDEWEB)

    Lexis, J.

    2002-05-01

    The blower characteristic as a rule is difficult to interpret. The contribution therefore discusses how it should be read and what information can be derived. It also goes into the influence of pressure changes on the operating point. [German] Die Kennliniendarstellung von Ventilatoren zeigt in der Regel eine verwirrende Fuelle von Linien, Kurven und Skalenstaeben, deren Bedeutung und Information zum gewaehlten Betriebspunkt nicht immer auf Anhieb erkennbar wird. Im folgenden soll daher einmal ausfuehrlich und detailliert auf die Informationen, die ein Kennlinienfeld bietet, eingegangen werden. Des weiteren werden die Betriebspunktaenderungen infolge von Druckverschiebungen erlaeutert. (orig.)

  9. Room acoustic analysis of blower unit and noise control plan in the typical steel industry

    Directory of Open Access Journals (Sweden)

    2013-02-01

    Full Text Available Introduction: In the steel industry,air blowers used to supply compressed air are considered as sources of annoying noise. This study aims to acoustics analysis of theairblower workroomand sound source characteristics in order to present noise controlmeasuresinthe steel industry. .Material and Method: Measurement of noiselevel and its frequency analysis was performed usingsound levelmetermodelof CASELLA-Cell.450. Distribution of noise level in the investigated workroom in form of noise map was provided using Surfer software. In addition, acoustic analysis of workroom and control room was performed in view point of soundabsorption andinsulation. Redesignofdoor and window of controlroom and installation of soundabsorbing materialson theceiling of the workroom were proposed and the efficiency of these interventionswasestimated. .Result: The totalsound pressurelevelin the blower workroom was 95.4 dB(L and the dominant frequency was 2000Hz. Sound pressure level inside the room control was 80.1dB(A. The average absorption coefficient and reverberation time in the blower workroom was estimated equal to 0.082 Sab.m2 and 3.9 seconds respectively. These value in control room was 0.04 Sab.m2 and 3/4 seconds respectively. In control room, sound transmission loss between the two parts of the wall dividing was 13.7 dB(A. The average of noise dose in blower operators was 230%. With the installation of sound absorber on ceiling of workroom, average of absorption coefficient can increase to 0.33 Sab.m2 and sound transmission loss of the new designed door and window was estimated equal to 20dB. . Conclusion: The main cause of noise leakage in the control room was insufficient insulation properties of door and windows. By replacing the door and window and installation of sound absorbing on ceiling of workroom, the noise dose can reduce to 49.6%. New Improved door and window of control room can reduce noise dose to 69.65% solely.

  10. A emergência da singularidade em uma cena didática de uma aula de geometria

    Directory of Open Access Journals (Sweden)

    Eveline Vieira Costa

    Full Text Available Resumo Este artigo tem por objetivo mostrar uma recriação de uma situação em sala de aula na qual o professor distribui o poder do saber com os alunos em uma estratégia que liga os saberes espontâneos, ou prévios, aos saberes abordados, de forma a fomentar a singularidade dos sujeitos. Para tanto, usaremos as noções de Bakhtin de zona de contato, a fim de defender a ideia da comunicação criativa como possibilidade de apropriação do conhecimento pelo aluno, através do discurso interno persuasivo, oriundo desse diálogo. Mostraremos como, dessa forma, o aluno se torna o que Lave e Wenger chamam membro periférico legítimo de uma comunidade de prática, aqui considerada a sala de aula. Em seguida, passaremos a considerar a dinâmica da sala de aula através do que Costa chama de problematização, subvertendo a tradição secular e/ou cultural do professor em posição central e os alunos em posições periféricas. Por fim, consideraremos essa dinâmica do ponto de vista psicológico, mostrando, a partir da ideia de Valsiner de internalização-externalização, como o conhecimento pronto e construído passa a possuir um sentido pessoal e afetivo para o aluno, a partir do uso de um exemplo ilustrativo em sala de aula sobre geometria.

  11. Fluid Flow in Continuous Casting Mold with a Configured Nozzle

    Institute of Scientific and Technical Information of China (English)

    王镭; 沈厚发; 柳百成

    2004-01-01

    The influence of a configured nozzle on the turbulent fluid flow in a continuous casting mold was investigated using the simulation program Visual Cast, which used the finite difference method and the SIMPLER algorithm. CAD software was used to construct the complicated nozzle in the calculational region. The simulation accuracy was validated by comparison with the classic driven cavity flow problem. The simulation results agree well with water modeling experiments. The simulations show that the velocity distribution at the nozzle port is uneven and the jet faces downward more than the nozzle outlet. Simulations with a configured nozzle and the inlet velocity at the nozzle entrance give precise results and overcome the traditional difficulty in determining the nozzle outlet velocity.

  12. Computational Fluid Dynamics Simulation of Dual Bell Nozzle Film Cooling

    Science.gov (United States)

    Braman, Kalen; Garcia, Christian; Ruf, Joseph; Bui, Trong

    2015-01-01

    Marshall Space Flight Center (MSFC) and Armstrong Flight Research Center (AFRC) are working together to advance the technology readiness level (TRL) of the dual bell nozzle concept. Dual bell nozzles are a form of altitude compensating nozzle that consists of two connecting bell contours. At low altitude the nozzle flows fully in the first, relatively lower area ratio, nozzle. The nozzle flow separates from the wall at the inflection point which joins the two bell contours. This relatively low expansion results in higher nozzle efficiency during the low altitude portion of the launch. As ambient pressure decreases with increasing altitude, the nozzle flow will expand to fill the relatively large area ratio second nozzle. The larger area ratio of the second bell enables higher Isp during the high altitude and vacuum portions of the launch. Despite a long history of theoretical consideration and promise towards improving rocket performance, dual bell nozzles have yet to be developed for practical use and have seen only limited testing. One barrier to use of dual bell nozzles is the lack of control over the nozzle flow transition from the first bell to the second bell during operation. A method that this team is pursuing to enhance the controllability of the nozzle flow transition is manipulation of the film coolant that is injected near the inflection between the two bell contours. Computational fluid dynamics (CFD) analysis is being run to assess the degree of control over nozzle flow transition generated via manipulation of the film injection. A cold flow dual bell nozzle, without film coolant, was tested over a range of simulated altitudes in 2004 in MSFC's nozzle test facility. Both NASA centers have performed a series of simulations of that dual bell to validate their computational models. Those CFD results are compared to the experimental results within this paper. MSFC then proceeded to add film injection to the CFD grid of the dual bell nozzle. A series of

  13. Blower door measurements. Guide 'Airtightness-testing' for house owners and planners; Blower-Door-Messung. Leitfaden 'Gebaeudedichtigkeits-Pruefung' fuer Bauherren und Planer. Fachtext 3.4. Maerz 2003

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-03-01

    To determine the air tightness of the external envelope, blower door measurements are normally carried out. The thus determined integral figure for the complete structure is an insufficient basis for carrying out specific insulation procedures in existing buildings. Within the scope of the air tightness measurements with the blower door, additional measuring methods permit the determination of additional information on the leakage distribution and the leakage routes. The expanded measuring methods that are known from the bibliography 'opening a door' and 'adding a hole' as well as the new method of 'adding a hole plus' are explained, compared by means of exemplary measurements, and are considered for their suitability during field trials. [German] Zur Bestimmung der Luftdichtheit der Gebaeudehuelle werden im allgemeinen Blower Door-Messungen durchgefuehrt. Der hierbei bestimmte integrale Wert fuer das gesamte Gebaeude stellt fuer das Ergreifen von gezielten Abdichtungsmassnahmen im Gebaeudebestand eine zu geringe Basis dar. Weiterfuehrende Messmethoden erlauben, im Rahmen von Luftdichtheitsmessungen mit der Blower Door zusaetzliche Informationen ueber die Leckageverteilung und ueber Leckagewege zu bestimmen. Die aus der Literatur bekannten erweiterten Messmethoden 'Opening A Door' und 'Adding A Hole' sowie die neue Methode 'Adding A Hole Plus' werden erlaeutert, anhand von exemplarischen Messungen verglichen und im Feldeinsatz auf ihre Anwendbarkeit hin betrachtet.

  14. Blower door measurement. Guide 'Airtightness-testing' for house owners and planners; Blower-Door-Messung. Leitfaden 'Gebaeudedichtigkeits-Pruefung' fuer Bauherren und Planer. Fachtext 3.4

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-08-15

    The blower door is a simple to use measuring device for determining the seal of the external surfaces of buildings. The accuracy of the measurement is dependent to a considerable extent on the external climatic conditions that prevail at the time of taking the measurement. (orig.)

  15. Blower door measurements. Guide 'Airtightness-testing' for house owners and planners; Blower-Door-Messung. Leitfaden 'Gebaeudedichtigkeits-Pruefung' fuer Bauherren und Planer. Fachtext 3.4. Mai 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-05-15

    The blower door is a simple to use measuring device for determining the seal of the external surfaces of buildings. The accuracy of the measurement is dependent to a considerable extent on the external climatic conditions that prevail at the time of taking the measurement. (GL)

  16. A robust and quick method for the estimation of long-term average indoor radon concentrations (extended Blower-Door method); Ein robustes und schnelles Verfahren zur Abschaetzung der langzeitlich mittleren Radonkonzentration in einem Gebaeude (erweiterte Blower-Door-Methode)

    Energy Technology Data Exchange (ETDEWEB)

    Maringer, F.J. [Bundesversuchs- und Forschungsanstalt Arsenal, Vienna (Austria); Akis, M.C.; Stadtmann, H. [Oesterreichisches Forschungszentrum Seibersdorf GmbH (Austria); Kaineder, H. [Amt der Oberoesterreichischen Landesregierung, Linz (Austria); Kindl, P. [Technische Univ., Graz (Austria); Kralik, C. [Bundesanstalt fuer Lebensmitteluntersuchung und -forschung, Vienna (Austria); Lettner, H.; Winkler, R. [Salzburg Univ. (Austria); Ringer, W. [Salzburg Univ. (Austria)]|[Atominstitut der Oesterreichischen Universitaeten, Vienna (Austria)

    1998-12-31

    Within the Austrian radon mitigation project `SARAH` different methods of radon diagnosis had been used. For these investigations a `Blower-Door` had been employed to apply a low pressure and to look for radon entry paths. On the occasion of the radon sniffing the team got the idea to measure the radon concentration in the Blower-Door exhaust air to get an estimate of the long-term average radon concentration in the building. In this paper the new method and their application possibilities are given. The estimation of the average radon entry rate, the average long-term radon concentration, and the evaluation of the mitigation success are described and discussed. The advantage of this procedure is to obtain a result for the annual mean indoor radon concentration after only about three hours. (orig.) [Deutsch] Im Rahmen des oesterreichischen Radonsanierungsprojekts `SARAH` wurden verschiedene Methoden zur Radondiagnose von Gebaeuden angewandt. Zum raschen Auffinden von Radoneintrittspfaden wurde auch ein `Blower-Door` zur Applikation eines Unterdrucks (-50 Pa) innerhalb der untersuchten Haeuser verwendet. Dabei entsprang die Idee, durch Messung der Radonkonzentration der Blower-Door-Abluft einen Hinweis auf die durchschnittliche Radonkonzentration im Gebaeude zu erhalten. In dieser Arbeit werden die neue Methode und deren Anwendungsmoeglichkeit zur Abschaetzung der mittleren Radoneintrittsrate und der langzeitlich mittleren Radonkonzentrationen (`Jahresmittelwert`) sowie des Sanierungserfolges (Ausmass der Radonreduktion) eines Gebaeudes beschrieben und diskutiert. Der Vorteil der Methode liegt darin, dass innerhalb von etwa drei Stunden Messzeit eine Abschaetzung fuer den Jahresmittelwert der Radonkonzentration eines Gebaeudes vorliegt. (orig.)

  17. O Movimento da Matemática Moderna e Diferentes Propostas Curriculares para o Ensino de Geometria no Brasil e em Portugal

    Directory of Open Access Journals (Sweden)

    José Manoel Matos

    2011-05-01

    Full Text Available O artigo tem o intuito de refletir sobre como as reformulações da matemática escolar durante o Movimento da Matemática Moderna (MMM afetam, interferem e modificam as propostas curriculares para o ensino de geometria no Brasil e em Portugal. O currículo de geometria é identificado como um problema (DETIENNE, 2000 que atravessa os dois países, fonte privilegiada para estudos comparativos. Analisamos livros didáticos destinados aos primeiros ciclos do ensino secundário e identificamos quatro casos nos dois países. Dois autores que mantém suas propostas para o ensino da geometria, António Palma Fernandes e Osvaldo Sangiorgi; e os livros de António de Almeida Costa e Alfredo Osório dos Anjos, por um lado, e os do Curso experimental da Bahia, que integram as novas idéias alterando profundamente o currículo geométrico. Em suma, concluímos que a elaboração de currículos apresentados nos livros didáticos não segue de forma linear as recomendações internacionais, mesmo quando elas não são uniformes, como no caso do currículo de geometria durante a Matemática Moderna. As produções deste novo momento curricular hibridizam as influências externas produzindo novas entidades culturais que não são cópias de recomendações curriculares internacionais. Antes procedem de forma diversificada, com maior ou menor sucesso, adaptando-se às contingências de cada sistema educativo. Palavras-chave: Movimento da Matemática Moderna. Ensino de geometria. Brasil. Portugal. The Modern Mathematics Movement and Distinct Curricular Proposals for Teaching Geometry in Brazil and in Portugal Abstract This article reflects about how changes in school mathematics during the Modern Mathematics Movement influence and modify curricular proposals for teaching geometry in Brazil and Portugal. Geometry curriculum is identified as a problem (DETIENNE, 2000 traversing the two countries, and consequently a privileged source for comparative

  18. Pumice in the interglacial Whidbey Formation at Blowers Bluff, central Whidbey Island, WA, USA

    Science.gov (United States)

    Dethier, D.P.; Dragovich, J.D.; Sarna-Wojcicki, A. M.; Fleck, R.J.

    2008-01-01

    A new 40Ar/39Ar age of 128??9 ka and chemical analyses of pumice layers from interglacial alluvium at Blowers Bluff, Whidbey Island, WA, show that the deposits are part of the Whidbey Formation, a widespread, mainly subsurface unit. Glass chemistry of the dated dacitic pumice does not match any analyzed northern Cascade source, but upper Pleistocene dacites from Glacier Peak and early Pleistocene silicic rocks from the Kulshan caldera are chemically similar. The chemistry of pumiceous dacite in younger units, including the latest Pleistocene Partridge Gravel, is similar to that of the dated material. The deep troughs of the modern northern Puget lowland must have been filled during deposition of the Whidbey Formation, allowing volcanic-rich sediment to reach what is now Whidbey Island. Topographic analysis of LIDAR images demonstrates that extensive erosion occurred during latest Pleistocene ice retreat. The Partridge Gravel likely records subglacial fluvial erosion along an ice tunnel and ice-marginal deposition into adjacent marine waters. Pumice in the Partridge Gravel probably was reworked from stratigraphically and topographically lower deposits, including those at Blowers Bluff. ?? 2007 Elsevier Ltd and INQUA.

  19. Design of the working channel for regenerative blowers; Dimensionierung des Arbeitskanals von Seitenkanalverdichtern

    Energy Technology Data Exchange (ETDEWEB)

    Surek, D. [Fachbereich Maschinenbau, Fachhochschule Merseburg (Germany); Galinsky, H. [Fachbereich Maschinenbau, Fachhochschule Merseburg (Germany)

    1996-04-01

    Regenerative blowers were built for pressure ratios from 1.2 to 1.5. They are used in many industrial areas for the compression of air and technical gases. They are also used as a compressor for coarse vacuum in the paper and polygraphic industrie. The design of the blower, especially the side channel, was done for incompression flow with a constant cross section of the side channel over all of the perimeter. The accessible pressure ratios make it necessary, to consider the alternation of the density by the designing of the machine and to have optimal flow in the side channel over all of the perimeter. In this article was shown the designing calculation for the cross section dependent on the peripheral angle and the most important quantities for the calculation given. (orig.) [Deutsch] Seitenkanalverdichter werden fuer Druckverhaeltnisse von {pi}=1,2 bis 1,5 gebaut und in vielen Industriebereichen zur Verdichtung von Luft und technischen Gasen sowie als Verdichter im Grobvakuumbereich in der Papier- und polygraphischen Industrie eingesetzt. Die Auslegung der Verdichter, insbesondere des Seitenkanals erfolgt bisher fuer inkompressible Stroemung mit konstantem Querschnitt im gesamten Umfangsbereich. Die angestrebten Druckverhaeltnisse zwingen jedoch dazu, die Dichteaenderung im Seitenkanal bei der Auslegung zu beruecksichtigen, wenn optimale Stroemungsverhaeltnisse im gesamten Seitenkanal angestrebt werden. Die Auslegungsrechnung mit dem Querschnittsverlauf des Seitenkanals in Abhaengigkeit des Umfangswinkels werden dargestellt und die wichtigsten Einflussgroessen fuer die Berechnung angegeben. (orig.)

  20. PDE Nozzle Optimization Using a Genetic Algorithm

    Science.gov (United States)

    Billings, Dana; Turner, James E. (Technical Monitor)

    2000-01-01

    Genetic algorithms, which simulate evolution in natural systems, have been used to find solutions to optimization problems that seem intractable to standard approaches. In this study, the feasibility of using a GA to find an optimum, fixed profile nozzle for a pulse detonation engine (PDE) is demonstrated. The objective was to maximize impulse during the detonation wave passage and blow-down phases of operation. Impulse of each profile variant was obtained by using the CFD code Mozart/2.0 to simulate the transient flow. After 7 generations, the method has identified a nozzle profile that certainly is a candidate for optimum solution. The constraints on the generality of this possible solution remain to be clarified.

  1. Explosion-protected blowers for removing explosive atmospheres from zone 0; Explosionsgeschuetzte Ventilatoren fuer die Foerderung von explosionsfaehiger Atmosphaere aus Zone 0

    Energy Technology Data Exchange (ETDEWEB)

    Frobese, D.H. [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany)

    2006-09-15

    Blowers for use in areas with high explosion hazards and/or for removal of explosive fluids are subject to directive 94/9/EG and must be explosion-protected according to Appendix II of that directive. So far, Germany only had VDMA specification leaflet 24169, which lists requirements on blowers for use in zones 1, 2, or 11. In the meantime, prEN 14986 has been elaborated which lists speciications for construction and testing of explosion-protected blowers. It applies to blower categories 1G, 2G or 3G, i.e. blowers for zones 0, 1, 2 or for explosive atmospheres in zones 1 or 2. It also applies to blowers of categories 2D and 3D, i.e. for transport of and/or use in areas with explosive dust/air mixtures of zones 21 and 22 but not air/dust mixtures of zone 20. The standard enables producers to assess the ignition hazard of an explosion-protected lower and lists constructional requirements and testing requirements. This enables the producer to construct explosion-proof blowers. The standard was intended for publication in the first half of 2006. (orig.)

  2. Jet Engine Exhaust Nozzle Flow Effector

    Science.gov (United States)

    Turner, Travis L. (Inventor); Cano, Roberto J. (Inventor); Silox, Richard J. (Inventor); Buehrle, Ralph D. (Inventor); Cagle, Christopher M. (Inventor); Cabell, Randolph H. (Inventor); Hilton, George C. (Inventor)

    2014-01-01

    A jet engine exhaust nozzle flow effector is a chevron formed with a radius of curvature with surfaces of the flow effector being defined and opposing one another. At least one shape memory alloy (SMA) member is embedded in the chevron closer to one of the chevron's opposing surfaces and substantially spanning from at least a portion of the chevron's root to the chevron's tip.

  3. Dual Nozzle Aerodynamic and Cooling Analysis Study.

    Science.gov (United States)

    1981-02-27

    ALRC Irwin Alber , Consultant Jim Duey, ALRC Joe Hoffman, Purdue University This report presents the Summary, Section I - Introduction, Section II...SCISEARCH. Papers which referred to the works of Korst, Bauer, and Alber were sought in this way. 19 I III, A, Literature Survey (cont.) The second...Point ’rfil Fna! ’w Turnino Annie Wall Anile at Attachrient Pnint hpar I ivPr ’hir r, ,ioz f Nnze Area Datioi P - Primary Nozzle Throa! Radius F Pati

  4. Flow Energy Piezoelectric Bimorph Nozzle Harvester

    Science.gov (United States)

    Sherrit, Stewart; Lee, Hyeong Jae; Kim, Namhyo; Sun, Kai; Corbett, Gary; Walkemeyer, Phillip; Hasenoehrl, Jennifer; Hall, Jeffery L.; Colonius, Tim; Tosi, Luis Phillipe; Arrazola, Alvaro

    2014-01-01

    There is a need for a long-life power generation scheme that could be used downhole in an oil well to produce 1 Watt average power. There are a variety of existing or proposed energy harvesting schemes that could be used in this environment but each of these has its own limitations. The vibrating piezoelectric structure is in principle capable of operating for very long lifetimes (decades) thereby possibly overcoming a principle limitation of existing technology based on rotating turbo-machinery. In order to determine the feasibility of using piezoelectrics to produce suitable flow energy harvesting, we surveyed experimentally a variety of nozzle configurations that could be used to excite a vibrating piezoelectric structure in such a way as to enable conversion of flow energy into useful amounts of electrical power. These included reed structures, spring mass-structures, drag and lift bluff bodies and a variety of nozzles with varying flow profiles. Although not an exhaustive survey we identified a spline nozzle/piezoelectric bimorph system that experimentally produced up to 3.4 mW per bimorph. This paper will discuss these results and present our initial analyses of the device using dimensional analysis and constitutive electromechanical modeling. The analysis suggests that an order-of-magnitude improvement in power generation from the current design is possible.

  5. Coherent structures in a supersonic complex nozzle

    Science.gov (United States)

    Magstadt, Andrew; Berry, Matthew; Glauser, Mark

    2016-11-01

    The jet flow from a complex supersonic nozzle is studied through experimental measurements. The nozzle's geometry is motivated by future engine designs for high-performance civilian and military aircraft. This rectangular jet has a single plane of symmetry, an additional shear layer (referred to as a wall jet), and an aft deck representative of airframe integration. The core flow operates at a Mach number of Mj , c = 1 . 6 , and the wall jet is choked (Mj , w = 1 . 0). This high Reynolds number jet flow is comprised of intense turbulence levels, an intricate shock structure, shear and boundary layers, and powerful corner vortices. In the present study, stereo PIV measurements are simultaneously sampled with high-speed pressure measurements, which are embedded in the aft deck, and far-field acoustics in the anechoic chamber at Syracuse University. Time-resolved schlieren measurements have indicated the existence of strong flow events at high frequencies, at a Strouhal number of St = 3 . 4 . These appear to result from von Kàrmàn vortex shedding within the nozzle and pervade the entire flow and acoustic domain. Proper orthogonal decomposition is applied on the current data to identify coherent structures in the jet and study the influence of this vortex street. AFOSR Turbulence and Transition Program (Grant No. FA9550-15-1-0435) with program managers Dr. I. Leyva and Dr. R. Ponnappan.

  6. Simple on-site assembled blower-mister device provides sufficient humidification and visualization in off-pump surgery.

    Science.gov (United States)

    Wippermann, Jens; Albes, Johannes M; Liebing, Kai; Breuer, Martin; Kaluza, Mirko; Strauch, Justus; Wahlers, Thorsten

    2006-09-01

    To effectively perform an anastomosis on a coronary artery under beating heart conditions, the anastomotic site must be cleared of blood to allow visualization for accurate suturing. We describe a simple, cost effective, on-site assembled blower-mister system.

  7. The impact of rotary lobe blower seal upgrades at INCO's Copper Cliff Nickel Refinery

    Energy Technology Data Exchange (ETDEWEB)

    Corless, C; Costigan, J. [INCO Copper Cliff Nickel Refinery, Copper Cliff, ON (Canada)

    2000-10-01

    INCO's Pressure Carbonyl (IPC) plant at Copper Cliff is unique in the world in that it utilizes the same basic chemistry, but forms the nickel carbonyl at high pressure to accelerate the reaction and utilize less pure refinery feeds. Two main process gases are used, namely carbon monoxide and nickel carbonyl which are transported throughout the plant using various compressors and blowers depending on whether the gas is at high pressure or at low pressure. The high-pressure transport is accomplished by three five-stage reciprocating compressors. There are numerous low pressure gas blowers; all of them must have seals to ensure that the gas does not escape into the plant atmosphere, and just as importantly, to prevent the lubricating oil from entering the process gases. This paper describes an incident in 1997 when Castrol R40, a lubricant, entered the IPC plant carrier gas stream, adversely affecting equipment availability and process control. The main source of the Castrol R40 was determined to be the carrier gas and low pressure gas blowers. The entry of Castrol R40 into the carrier gas stream was successfully prevented when the mechanical shaft seals were replaced with Ferrofluidics seals. Details of the resulting new sealing arrangements, the status of blower upgrade project and results achieved to date are reviewed.

  8. Blower door tests of a group of identical flats in a new student accommodation in the Arctic

    DEFF Research Database (Denmark)

    Kotol, Martin; Rode, Carsten; Vahala, Jan

    air quality (IAQ) as well as performance of some single components. In summer 2012 a blower door test was performed on all 37 living units out of which 33 are identical single room flats and 4 are larger double room flats. The purpose was to evaluate the air tightness of the envelope and to find out...

  9. Drum rotor blowers in EC technology. Energy conservation, comfortable control, low noise; Trommellaeufer-Ventilatoren in EC-Technik. Energieersparnis, komfortable Regelung und geringe Geraeuschentwicklung

    Energy Technology Data Exchange (ETDEWEB)

    Sigloch, U. [ebm-papst Mulfingen GmbH und Co. KG (Germany). Projektmanagement Vertrieb Europa; Reiff, E.C. [Redaktionsbuero Stutensee (Germany)

    2008-07-01

    Compact drum rotor blowers with forward-curved blades are quite common in air conditioning and ventilation because of their high efficiency and compact dimensions. They are found in air conditioner boxes, in air current systems in department stores, or in fan coils in hotel rooms, wherever other types of blowers would be too big. Until recently, EC technology was not available for the blower motors so the users had do accept low efficiency and the poor control options of conventional AC drives. This has changed by now. (orig.)

  10. Energy conservation measures cause damage to radial blowers; Mechanical consequences are not always taken into account. Energiebesparing kraakt radiale ventilatoren; Mechanische consequenties worden niet altijd onderkend

    Energy Technology Data Exchange (ETDEWEB)

    Hillebrand, A.F. (Hoogovens IJmuiden (Netherlands))

    1991-02-01

    Hoogovens IJmuiden, the iron and steel division of the Hoogovens Groep, has tried to save energy by changing the operation mode of installed blowers, which have capacities to 2.5 MW. Instead of continuous operation a start-stop procedure has been introduced. However, service life of the blowers can be affected seriously because mechanical damage of impellers by fatigue has been observed. Replacement or better constructed impellers increase costs or investment and the latter demands skill of blower producers which is not always available. 3 figs., 2 refs., 1 ill.

  11. Details of Side Load Test Data and Analysis for a Truncated Ideal Contour Nozzle and a Parabolic Contour Nozzle

    Science.gov (United States)

    Ruf, Joseph H.; McDaniels, David M.; Brown, Andrew M.

    2010-01-01

    Two cold flow subscale nozzles were tested for side load characteristics during simulated nozzle start transients. The two test article contours were a truncated ideal and a parabolic. The current paper is an extension of a 2009 AIAA JPC paper on the test results for the same two nozzle test articles. The side load moments were measured with the strain tube approach in MSFC s Nozzle Test Facility. The processing techniques implemented to convert the strain gage signals into side load moment data are explained. Nozzle wall pressure profiles for separated nozzle flow at many NPRs are presented and discussed in detail. The effect of the test cell diffuser inlet on the parabolic nozzle s wall pressure profiles for separated flow is shown. The maximum measured side load moments for the two contours are compared. The truncated ideal contour s peak side load moment was 45% of that of the parabolic contour. The calculated side load moments, via mean-plus-three-standard-deviations at each nozzle pressure ratio, reproduced the characteristics and absolute values of measured maximums for both contours. The effect of facility vibration on the measured side load moments is quantified and the effect on uncertainty is calculated. The nozzle contour designs are discussed and the impact of a minor fabrication flaw in the nozzle contours is explained.

  12. Navier-Stokes predictions of multifunction nozzle flows

    Science.gov (United States)

    Wilmoth, Richard G.; Leavitt, Laurence D.

    1987-10-01

    A two-dimensional, Navier-Stokes code developed by Imlay based on the implicit, finite-volume method of MacCormack has been applied to the prediction of the flow fields and performance of several nonaxisymmetric, convergent-divergent nozzles with and without thrust vectoring. Comparisons of predictions with experiment show that the Navier-Stokes code can accurately predict both the flow fields and performance for nonaxisymmetric nozzles where the flow is predominantly two-dimensional and at nozzle pressure ratios at or above the design values. Discrepancies between predictions and experiment are noted at lower nozzle pressure ratios where separation typically occurs in portions of the nozzle. The overall trends versus parameters such as nozzle pressure ratio, flap angle, and vector angle were generally predicted correctly.

  13. Fluidized-bed calciner with combustion nozzle and shroud

    Science.gov (United States)

    Wielang, Joseph A.; Palmer, William B.; Kerr, William B.

    1977-01-01

    A nozzle employed as a burner within a fluidized bed is coaxially enclosed within a tubular shroud that extends beyond the nozzle length into the fluidized bed. The open-ended shroud portion beyond the nozzle end provides an antechamber for mixture and combustion of atomized fuel with an oxygen-containing gas. The arrangement provides improved combustion efficiency and excludes bed particles from the high-velocity, high-temperature portions of the flame to reduce particle attrition.

  14. Bergemann lance-type water blowers for coal boilers; Bergemann-Wasserlanzenblaeser fuer Kohlekessel

    Energy Technology Data Exchange (ETDEWEB)

    Bartels, F.; Weber, H.G.

    1995-12-31

    Residues from coal combustion create considerable problems for boilers. Slag and ashes on heating surfaces have a negative influence on steam generator efficiency and reduce boiler cycles. If different types of coal are used there are not only specific demands for stable furnace operation but problems of slag control at the different steam generator surfaces. Vaporiser heating surfaces of combustion chambers show extra-tough slag which can not always be removed by steam or air blowers. Forty years ago one therefore started using water as an alternative cleaning agent. At first, hand-held lances were used. Due to its high kinetic energy, water jets penetrate the pores of the slag layers on the vaporiser pipes where it evaporates and makes the slag pop off due to the sudden considerable increase in volume. These results consequently lead to the mechanisation of water-blowing as early as the 1950s; steam soot blowers were retrofitted for water. The Bergemann company used its own system of wall-blowers and improved the water blowing technology with the help of RWE by testing the technology under real life conditions in one or RWE`s lignite power stations. (orig.) [Deutsch] Rueckstaende aus der Verbrennung von Kohle-Brennstoffen fuehren beim Betrieb von Kesselanlagen zu erheblichen Problemen. Der Wirkungsgrad der Dampferzeuger wird durch zum Teil hartnaeckige Ansaetze von Schlacken und Aschen auf den Heizflaechen negativ beeinflusst und die Kessel-Reisezeit herabgesetzt. Besonders die Verbrennung von verschiedenen Kohlearten mit einem breiten Brennstoffband fuehrt neben spezifischen Anforderungen an den stabilen Feuerungsbetrieb vor allem auch zu den Fragen der Beherrschung von Verschlackungen an den unterschiedlichen Dampferzeugerheizflaechen. An den Verdampferheizflaechen der Brennkammern koennen besonders hartnaeckige Verschlackungen auftreten, die mit Dampf und Luft als Blasmedium nicht immer zu entfernen sind. Wasser wurde deshalb als alternatives Reinigungsmedium

  15. Heat and fluid flow properties of circular impinging jet with a low nozzle to plate spacing. Improvement by nothched nozzle; Nozzle heibankan kyori ga chiisai baai no enkei shototsu funryu no ryudo dennetsu tokusei. Kirikaki nozzle ni yoru kaizen kojo

    Energy Technology Data Exchange (ETDEWEB)

    Shakouchih, T. [Mie University, Mie (Japan). Faculty of Engineering; Matsumoto, A.; Watanabe, A.

    2000-10-25

    It is well known that as decreasing the nozzle to plate spacing considerably the heat transfer coefficient of circular impinging jet, which impinges to the plate normally, increases remarkably. At that time, the flow resistance of nozzle-plate system also increases rapidly. In this study, in order to reduce the flow resistance and to enhance the heat transfer coefficient of the circular impinging jet with a considerably low nozzle to plate spacing, a special nozzle with notches is proposed, and considerable improvement of the flow and heat transfer properties are shown. The mechanism of enhancement of the heat transfer properties is also discussed. (author)

  16. Evaluation of nozzle shapes for an optical flow meter

    Science.gov (United States)

    Sheikholeslami, M. Z.; Patel, B. R.

    1992-05-01

    Numerical modeling is performed for turbulent flow in axisymmetric nozzles using Creare's computer program FLUENT/BFC. The primary objective of the project was to assist Spectron Development Laboratories in selecting an optimum nozzle shape for an optical flowmeter. The nozzle performance is evaluated for various length to diameter ratios, area contraction ratios, and Reynolds numbers. The computations have demonstrated that a cubic profile nozzle with length to diameter ratio of 1.6 and area contraction ratio of 6.2 can decrease the velocity profile non-uniformity from 15 percent at the entrance to 1 percent at the exit. The configuration is recommended for further investigation.

  17. Experimental study of subsonic microjet escaping from a rectangular nozzle

    Science.gov (United States)

    Aniskin, V. M.; Maslov, A. A.; Mukhin, K. A.

    2016-10-01

    The first experiments on the subsonic laminar microjets escaping from the nozzles of rectangular shape are carried out. The nozzle size is 83.3x3823 microns. Reynolds number calculated by the nozzle height and the average flow velocity at the nozzle exit ranged from 58 to 154. The working gas was air at room temperature. The velocity decay and velocity fluctuations along the center line of the jet are determined. The fundamental difference between the laminar microjets characteristics and subsonic turbulent jets of macro size is shown. Based on measurements of velocity fluctuations it is shown the presence of laminar-turbulent transition in microjets and its location is determined.

  18. Low Cost Carbon-Carbon Rocket Nozzle Development Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This development will provide an inexpensive vacuum nozzle manufacturing option for NOFBXTM monopropellant systems that are currently being developed under NASA SBIR...

  19. Variable volume combustor with aerodynamic fuel flanges for nozzle mounting

    Energy Technology Data Exchange (ETDEWEB)

    McConnaughhay, Johnie Franklin; Keener, Christopher Paul; Johnson, Thomas Edward; Ostebee, Heath Michael

    2016-09-20

    The present application provides a combustor for use with a gas turbine engine. The combustor may include a number of micro-mixer fuel nozzles and a fuel injection system for providing a flow of fuel to the micro-mixer fuel nozzles. The fuel injection system may include a number of support struts supporting the fuel nozzles and for providing the flow of fuel therethrough. The fuel injection system also may include a number of aerodynamic fuel flanges connecting the micro-mixer fuel nozzles and the support struts.

  20. Flow separation in rocket nozzles under high altitude condition

    Science.gov (United States)

    Stark, R.; Génin, C.

    2017-01-01

    The knowledge of flow separation in rocket nozzles is crucial for rocket engine design and optimum performance. Typically, flow separation is studied under sea-level conditions. However, this disregards the change of the ambient density during ascent of a launcher. The ambient flow properties are an important factor concerning the design of altitude-adaptive rocket nozzles like the dual bell nozzle. For this reason an experimental study was carried out to study the influence of the ambient density on flow separation within conventional nozzles.

  1. Analysis of Nozzle Jet Plume Effects on Sonic Boom Signature

    Science.gov (United States)

    Bui, Trong

    2010-01-01

    An axisymmetric full Navier-Stokes computational fluid dynamics (CFD) study was conducted to examine nozzle exhaust jet plume effects on the sonic boom signature of a supersonic aircraft. A simplified axisymmetric nozzle geometry, representative of the nozzle on the NASA Dryden NF-15B Lift and Nozzle Change Effects on Tail Shock (LaNCETS) research airplane, was considered. The highly underexpanded nozzle flow is found to provide significantly more reduction in the tail shock strength in the sonic boom N-wave pressure signature than perfectly expanded and overexpanded nozzle flows. A tail shock train in the sonic boom signature, similar to what was observed in the LaNCETS flight data, is observed for the highly underexpanded nozzle flow. The CFD results provide a detailed description of the nozzle flow physics involved in the LaNCETS nozzle at different nozzle expansion conditions and help in interpreting LaNCETS flight data as well as in the eventual CFD analysis of a full LaNCETS aircraft. The current study also provided important information on proper modeling of the LaNCETS aircraft nozzle. The primary objective of the current CFD research effort was to support the LaNCETS flight research data analysis effort by studying the detailed nozzle exhaust jet plume s imperfect expansion effects on the sonic boom signature of a supersonic aircraft. Figure 1 illustrates the primary flow physics present in the interaction between the exhaust jet plume shock and the sonic boom coming off of an axisymmetric body in supersonic flight. The steeper tail shock from highly expanded jet plume reduces the dip of the sonic boom N-wave signature. A structured finite-volume compressible full Navier-Stokes CFD code was used in the current study. This approach is not limited by the simplifying assumptions inherent in previous sonic boom analysis efforts. Also, this study was the first known jet plume sonic boom CFD study in which the full viscous nozzle flow field was modeled, without

  2. Calculation of the temperature distribution and thermal stresses in a gas turbine nozzle cooled by air film; Calculo de la distribucion de temperaturas y esfuerzos termicos en una tobera de turbina de gas enfriada por pelicula de aire

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez R, Alejandro; Garcia I, Rafael; Mazur C, Zdislaw [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2004-07-01

    The analysis begins with the generation of a computational geometric model of the gas turbine nozzle using reverse engineering techniques. For the obtaining of the original geometry of the blade, a measurement machine by coordinates and computerized numerical control was used. Next, the computational model is converted into a three-dimensional mesh. In advance, a study of boundary conditions was made of the nozzle material as well as of the turbine operating conditions during non-operating cycles, start-ups and shut-downs. On the other hand, with the boundary conditions imposed to the model, the distributions of the temperature and pressures on the aerofoil profile of the nozzle blade were calculated. These results had to be manipulated to be exported to a finite element software (ANSYS); at this point, another nozzle model was elaborated to be able to import the temperature distribution. With the temperatures correctly imported, the simulations for the calculation of the thermal stresses were made in the nozzle. [Spanish] El analisis inicia con la generacion de un modelo geometrico computacional de la tobera de la turbina de gas utilizando tecnicas de ingenieria inversa. Para la obtencion de la geometria original del alabe, se utilizo una maquina de medicion por coordenadas y control numerico computarizado. A continuacion, el modelo computacional es convertido en una malla tridimensional. Con antelacion, se realizo un estudio de las condiciones de frontera, tanto del material de la tobera como de las condiciones de operacion de la turbina, durante ciclos de paro, arranque y disparo. Por otra parte, con las condiciones de frontera impuestas al modelo, se calcularon las distribuciones de las temperaturas y presiones sobre el perfil aerodinamico de la paleta de la tobera. Estos resultados tuvieron que ser manipulados para ser exportados a un software de elemento finito (ANSYS); en este punto, se elaboro otro modelo de la tobera para poder importar la distribucion de

  3. Enhancing the operational dependability of oil and gas burners: radial blowers with compression in two stages; Zur Erhoehung der Betriebssicherheit von Oel- und Gasbrennern: Radialgeblaese mit zweistufiger Verdichtung

    Energy Technology Data Exchange (ETDEWEB)

    Koehler, H. [Produktmanagement Anwendungstechnik, Oertli-Rohleder Waermetechnik GmbH, Moeglingen (Germany)

    1999-02-01

    A blower system for oil and gas burners with blowers (Duopress) is described which achieves high blower compression at low rates of air intake. The high starting resistance of burners is thus easily overcome and operational dependability is much enhanced. Moreover, the system permits modular construction of burner blowers. As a consequence, different sizes of burners can be built and their ease of maintenance is enhanced. (orig.) [Deutsch] Es wird ein Geblaesesystem fuer Oel- oder Gasgeblaesebrenner (Duopress) vorgestellt, welches es ermoeglicht, hohe Geblaesepressungen bei niedrigem Luftvolumenstrom zu erreichen. So lassen sich die hohen Anfahrwiderstaende bei den Brennerstarts muehelos ueberwinden, und man kann eine deutlich gesteigerte Betriebssicherheit erreichen. Das vorgestellte System ermoeglicht zudem eine modulare Bauweise der Brennergeblaese. Dadurch koennen auf einfache Art verschiedene Baugroessen eines Brenners realisiert und die Wartungsfreundlichkeit der Brenner gesteigert werden. (orig.)

  4. Blower speed variation in refrigeration engineering and potential applications; Verschiedene Verfahren der Drehzahlveraenderung von Ventilatoren in der Kaeltetechnik mit einer Betrachtung moeglicher Anwendungsfaelle

    Energy Technology Data Exchange (ETDEWEB)

    Albig, J. [Ziehl-Abegg AG, Kuenzelsau (Germany)

    2006-07-01

    Various methods of blower speed control in refrigeration engineering enable user-oriented efficiency increase in axial blowers in refrigeration engineering. Apart from the motor efficiency, the economic efficiency of a blower is also determined by the investment cost of speed control systems. The blower efficiency is left out of account in this contribution. The most common control systems were compared, i.e. voltage control, frequency control and EC control. For an optimum result, the optimum system must be selected already in the planning stage. For this, the advantages and shortcomings must be known for each solution and application. Exemplary recommendations are given for various applications, and the speed control systems described are compared with regard to their efficiency and investment cost. (orig.)

  5. Use of lance-type water blowers in refuse incineration plants; Einsatz von Wasserlanzenblaesern in Muellverbrennungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Schaefers, W.; Fey, W. [Babcock-Steinmueller GmbH, Gummersbach (Germany); Simon, S.; Kahle, F.D. [Clyde Bergemann GmbH, Wesel (Germany)

    1999-10-01

    In order to achieve the desired boiler campaign lengths in refuse incineration plants, cleaning devices are an absolute necessity. Whereas the cleaning of convective heating surfaces in vertical-pass and horizontal-pass boilers presents no great difficulty, the possibilities for effective cleaning of the radiant passes were up to now limited. The use of lance-type water blowers has considerably improved this situation. (orig.) [German] Um die gewuenschten Reisezeiten bei Muellverbrennungsanlagen einhalten zu koennen, ist der Einsatz von Reinigungseinrichtungen notwendig. Waehrend die Reinigung der Konvektivheizflaechen bei Vertikal- und Horizontalzugkesseln keine Probleme bereitet, waren bisher die Moeglichkeiten zur Reinhaltung der Strahlungszuege begrenzt. Durch den Einsatz von Wasserlanzenblaesern ergibt sich hier eine deutlich verbesserte Situation. (orig.)

  6. Blowers in bus systems; Einsatz von Ventilatoren in BUS-Systemen

    Energy Technology Data Exchange (ETDEWEB)

    Schneeweiss, H. [ebm - Werke GmbH und Co., Mulfingen (Germany). R und D

    2000-07-01

    Modern industrial blowers are compact and have good control characteristics. Centralized or decentralized monitoring has become a state-of-the-art technology. Bus systems make it possible to monitor and analyze component status at any time. Electronically commutated external rotor motors with bus interfaces offer a wide spectrum of applications. [German] Beim Einsatz von Ventilatoren und Geblaesen in der Industrie ist es heute Standard, dass die Geraete einen kompakten Aufbau und gute Regel- bzw. Steuereigenschaften aufweisen. Immer mehr setzt sich auch die zentrale und dezentrale Ueberwachung von Geraeten durch. Mit einem BUS-System kann der aktuelle Status jeder Komponente jederzeit abgefragt und der Zustand analysiert werden. Durch spezielle Einsatzbedingungen werden heute elektronisch kommutierte Aussenlaeufermotoren mit BUS-Schnittstellen versehen. Damit steht ein breites Anwendungsspektrum zur Verfuegung. (orig.)

  7. A Blower-Like Approach to Predict the Effectiveness of Vaccines in a TB Dynamic Carlos

    Directory of Open Access Journals (Sweden)

    Frederico Fronza

    2014-06-01

    Full Text Available In this paper we present an extension of an automata approach proposed by S. Blower (1998 to describe the tuberculosis progression in a bi-dimensional space. In our extended model, the vaccination was included as an inhibitory variable in order to study its influence on the behavior of the tuberculosis spread. Our simulations showed that the earlier the vaccine is administered in the population, the lower the number of infected individuals, as expected for an in vivo system. However, our results also indicated that although the usual vaccination processes help reducing the strength of infection, the disease is not extinct, remaining the endemic state at low levels. These results strongly suggest that further actions are needed to increase the effectiveness of immunizations.

  8. Testicular cancer trends as 'whistle blowers' of testicular developmental problems in populations

    DEFF Research Database (Denmark)

    Skakkebaek, N E; Rajpert-De Meyts, Ewa; Jørgensen, N;

    2007-01-01

    in TGCC rates of a population may be 'whistle blowers' of other reproductive health problems. As cancer registries are often of excellent quality - in contrast to registries for congenital abnormalities - health authorities should consider an increase in TGCC as a warning that other reproductive health......Recently a worldwide rise in the incidence of testicular germ cell cancer (TGCC) has been repeatedly reported. The changing disease pattern may signal that other testicular problems may also be increasing. We have reviewed recent research progress, in particular evidence gathered in the Nordic....../disorders of sex differentiation and male fertility problems may be symptoms with varying penetration. In spite of their fetal origin, most of the TDS symptoms, including TGCC and poor semen quality, can only be diagnosed in adulthood. Data from a Danish-Finnish research collaboration strongly suggest that trends...

  9. Testicular cancer trends as 'whistle blowers' of testicular developmental problems in populations

    DEFF Research Database (Denmark)

    Skakkebaek, N E; Rajpert-De Meyts, E; Jørgensen, N

    2007-01-01

    Recently a worldwide rise in the incidence of testicular germ cell cancer (TGCC) has been repeatedly reported. The changing disease pattern may signal that other testicular problems may also be increasing. We have reviewed recent research progress, in particular evidence gathered in the Nordic...... countries, which shows strong associations between testicular cancer, undescended testis, hypospadias, poor testicular development and function, and male infertility. These studies have led us to suggest the existence of a testicular dysgenesis syndrome (TDS), of which TGCC, undescended testis, hypospadias...... in TGCC rates of a population may be 'whistle blowers' of other reproductive health problems. As cancer registries are often of excellent quality - in contrast to registries for congenital abnormalities - health authorities should consider an increase in TGCC as a warning that other reproductive health...

  10. Study of nozzle deposit formation mechanism for direct injection gasoline engines; Chokufun gasoline engine yo nozzle no deposit seisei kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, M.; Saito, A. [Toyota Central Research and Development Labs., Inc., Aichi (Japan); Matsushita, S. [Toyota Motor Corp., Aichi (Japan); Shibata, H. [Nippon Soken, Inc., Tokyo (Japan); Niwa, Y. [Denso Corp., Aichi (Japan)

    1997-10-01

    Nozzles in fuel injectors for direct injection gasoline engines are exposed to high temperature combustion gases and soot. In such a rigorous environment, it is a fear that fuel flow rate changes in injectors by deposit formation on nozzles. Fundamental factors of nozzle deposit formation were investigated through injector bench tests and engine dynamometer tests. Deposit formation processes were observed by SEM through engine dynamometer tests. The investigation results reveal nozzle deposit formation mechanism and how to suppress the deposit. 4 refs., 8 figs., 3 tabs.

  11. Simulating radiative shocks in nozzle shock tubes

    Science.gov (United States)

    van der Holst, B.; Tóth, G.; Sokolov, I. V.; Daldorff, L. K. S.; Powell, K. G.; Drake, R. P.

    2012-06-01

    We use the recently developed Center for Radiative Shock Hydrodynamics (CRASH) code to numerically simulate laser-driven radiative shock experiments. These shocks are launched by an ablated beryllium disk and are driven down xenon-filled plastic tubes. The simulations are initialized by the two-dimensional version of the Lagrangian Hyades code which is used to evaluate the laser energy deposition during the first 1.1 ns. Later times are calculated with the CRASH code. CRASH solves for the multi-material hydrodynamics with separate electron and ion temperatures on an Eulerian block-adaptive-mesh and includes a multi-group flux-limited radiation diffusion and electron thermal heat conduction. The goal of the present paper is to demonstrate the capability to simulate radiative shocks of essentially three-dimensional experimental configurations, such as circular and elliptical nozzles. We show that the compound shock structure of the primary and wall shock is captured and verify that the shock properties are consistent with order-of-magnitude estimates. The synthetic radiographs produced can be used for comparison with future nozzle experiments at high-energy-density laser facilities.

  12. Magnetic Nozzle Simulation Studies for Electric Propulsion

    Science.gov (United States)

    Tarditi, Alfonso

    2010-11-01

    Electric Propulsion has recently re-gained interest as one of the key technologies to enable NASA's long-range space missions. Options are being considered also in the field of aneutronic fusion propulsion for high-power electric thrusters. To support these goals the study of the exhaust jet in a plasma thruster acquires a critical importance because the need of high-efficiency generation of thrust. A model of the plasma exhaust has been developed with the 3D magneto-fluid NIMROD code [1] to study the physics of the plasma detachment in correlation with experimentally relevant configurations. The simulations show the role of the plasma diamagnetism and of the magnetic reconnection process in the formation of a detached plasma. Furthermore, in direct fusion-propulsion concepts high-energy (MeV range) fusion products have to be efficiently converted into a slower and denser plasma jet (with specific impulse down to few 1000's seconds, for realistic missions in the Solar System). For this purpose, a two-stage conversion process is being modeled where high-energy ions are non-adiabatically injected and confined into a magnetic duct leading to the magnetic nozzle, transferring most of their energy into their gyro-motion and drifting at slower speed along with the plasma propellant. The propellant acquires then thermal energy that gets converted into the direction of thrust by the magnetic nozzle. [1] C. R. Sovinec et al., J. Comput. Phys. 195, 355 (2004).

  13. Instability of jet plume from an overexpanded nozzle

    Science.gov (United States)

    Papamoschou, Dimitri

    2005-11-01

    Our study involves the phenomenon of supersonic nozzle flow separation wherein a shock forms inside a convergent-divergent nozzle. Of particular interest is the instability of the jet plume exiting this type of nozzle. A rectangular apparatus of aspect ratio 3.57 and flexible walls enabled a parametric study of the mean and turbulent properties of the jet plume versus nozzle pressure ratio (from 1.2 to 2.0), exit-to-throat area ratio (from 1.0 to 1.8) and wall divergence angle at the nozzle exit (from 0 to 4 deg.) Time-resolved surveys of total pressure were obtained by means of a dynamic Pitot probe. The growth rate of the jet and the peak rms value of total pressure fluctuation near the nozzle exit increase several fold with area ratio. This trend becomes most pronounced for nozzle pressure ratio around 1.6. At fixed area ratio and nozzle pressure ratio, the wall divergence angle has little effect on the instability.

  14. Rapid Fabrication Techniques for Liquid Rocket Channel Wall Nozzles

    Science.gov (United States)

    Gradl, Paul R.

    2016-01-01

    The functions of a regeneratively-cooled nozzle are to (1) expand combustion gases to increase exhaust gas velocity while, (2) maintaining adequate wall temperatures to prevent structural failure, and (3) transfer heat from the hot gases to the coolant fluid to promote injector performance and stability. Regeneratively-cooled nozzles are grouped into two categories: tube-wall nozzles and channel wall nozzles. A channel wall nozzle is designed with an internal liner containing a series of integral coolant channels that are closed out with an external jacket. Manifolds are attached at each end of the nozzle to distribute coolant to and away from the channels. A variety of manufacturing techniques have been explored for channel wall nozzles, including state of the art laser-welded closeouts and pressure-assisted braze closeouts. This paper discusses techniques that NASA MSFC is evaluating for rapid fabrication of channel wall nozzles that address liner fabrication, slotting techniques and liner closeout techniques. Techniques being evaluated for liner fabrication include large-scale additive manufacturing of freeform-deposition structures to create the liner blanks. Abrasive water jet milling is being evaluated for cutting the complex coolant channel geometries. Techniques being considered for rapid closeout of the slotted liners include freeform deposition, explosive bonding and Cold Spray. Each of these techniques, development work and results are discussed in further detail in this paper.

  15. Analytical study of nozzle performance for nuclear thermal rockets

    Science.gov (United States)

    Davidian, Kenneth O.; Kacynski, Kenneth J.

    1991-01-01

    Nuclear propulsion has been identified as one of the key technologies needed for human exploration of the Moon and Mars. The Nuclear Thermal Rocket (NTR) uses a nuclear reactor to heat hydrogen to a high temperature followed by expansion through a conventional convergent-divergent nozzle. A parametric study of NTR nozzles was performed using the Rocket Engine Design Expert System (REDES) at the NASA Lewis Research Center. The REDES used the JANNAF standard rigorous methodology to determine nozzle performance over a range of chamber temperatures, chamber pressures, thrust levels, and different nozzle configurations. A design condition was set by fixing the propulsion system exit radius at five meters and throat radius was varied to achieve a target thrust level. An adiabatic wall was assumed for the nozzle, and its length was assumed to be 80 percent of a 15 degree cone. The results conclude that although the performance of the NTR, based on infinite reaction rates, looks promising at low chamber pressures, finite rate chemical reactions will cause the actual performance to be considerably lower. Parameters which have a major influence on the delivered specific impulse value include the chamber temperature and the chamber pressures in the high thrust domain. Other parameters, such as 2-D and boundary layer effects, kinetic rates, and number of nozzles, affect the deliverable performance of an NTR nozzle to a lesser degree. For a single nozzle, maximum performance of 930 seconds and 1030 seconds occur at chamber temperatures of 2700 and 3100 K, respectively.

  16. Influence of different developer nozzle types on the photomask performance

    Science.gov (United States)

    Schmädicke, Cindy; Feicke, Axel; Herrmann, Mark; Bürgel, Christian

    2016-05-01

    The long-term development of electronics obliges increasingly tighter specifications for photomasks to meet the requirements of continuing miniaturization. We report on the influence of two different linear drive nozzle types A and B used for conducting the develop process on important mask properties, which comprise CD uniformity (CDU), loading behaviour, mean to target (MTT), iso-dense bias, line width roughness (LWR), linearity, resolution and defectivity. The results are presented for different resists, resist thicknesses and blank materials. First, the most important recipe parameters to ensure the best develop performance are defined and experimentally determined. Those critical factors are the nozzle scan speed over the mask, the develop time, the distance between nozzle and mask surface and the flow rate of the medium. It is demonstrated how these parameters can significantly affect the develop process performance. Dark loss experiments reveal that a more uniform resist removal takes place with the B kind of nozzle compared to that achieved with nozzle A. Based on the mask properties, the performances of two different nozzle types are compared. It is found that improvements with the B like nozzle can be achieved for CDU and loading. The presented nozzle type shows a promising approach to meet the requirements of future electronics.

  17. Acoustic measurements of models of military style supersonic nozzle jets

    NARCIS (Netherlands)

    Kuo, C.W.; Veltin, J.; McLaughlin, D.K.

    2014-01-01

    Modern military aircraft jet engines are designed with variable-geometry nozzles to provide optimal thrust in different operating conditions, depending on the flight envelope. However, acoustic measurements for such nozzles are scarce, due to the cost involved in making full-scale measurements and t

  18. Shape memory alloy actuated adaptive exhaust nozzle for jet engine

    Science.gov (United States)

    Song, Gangbing (Inventor); Ma, Ning (Inventor)

    2009-01-01

    The proposed adaptive exhaust nozzle features an innovative use of the shape memory alloy (SMA) actuators for actively control of the opening area of the exhaust nozzle for jet engines. The SMA actuators remotely control the opening area of the exhaust nozzle through a set of mechanism. An important advantage of using SMA actuators is the reduction of weight of the actuator system for variable area exhaust nozzle. Another advantage is that the SMA actuator can be activated using the heat from the exhaust and eliminate the need of other energy source. A prototype has been designed and fabricated. The functionality of the proposed SMA actuated adaptive exhaust nozzle is verified in the open-loop tests.

  19. Nozzle cooling of hot surfaces with various orientations

    Directory of Open Access Journals (Sweden)

    Horsky Jaroslav

    2012-04-01

    Full Text Available The aim of this research is an investigation of hot surface orientation influence on heat transfer during cooling by a nozzle. Two types of nozzles were used for the experiments (air-mist nozzle and hydraulic nozzle. A test plate was cooled in three positions – top, side and bottom position. The aim was to simulate a cooling situation in the secondary zone of a continuous casting machine. Temperature was measured in seven locations under the cooled surface by thermocouples. These data were used for an inverse heat conduction problem and then boundary conditions were computed. These boundary conditions are represented by surface temperature, heat transfer coefficient and heat flux. Results from an inverse calculation were compared in each position of thermocouples separately. The total cooling intensity was specified for all configurations of nozzles and test plate orientation. Results are summarised in a graphical and numerical format.

  20. Cosmet'eau-Changes in the personal care product consumption practices: from whistle-blowers to impacts on aquatic environments.

    Science.gov (United States)

    Bressy, Adèle; Carré, Catherine; Caupos, Émilie; de Gouvello, Bernard; Deroubaix, José-Frédéric; Deutsch, Jean-Claude; Mailler, Romain; Marconi, Anthony; Neveu, Pascale; Paulic, Laurent; Pichon, Sébastien; Rocher, Vincent; Severin, Irina; Soyer, Mathilde; Moilleron, Régis

    2016-07-01

    The Cosmet'eau project (2015-2018) investigates the "changes in the personal care product (PCP) consumption practices: from whistle-blowers to impacts on aquatic environments." In this project, the example of PCPs will be used to understand how public health concerns related to micropollutants can be addressed by public authorities-including local authorities, industries, and consumers. The project aims to characterize the possible changes in PCP consumption practices and to evaluate the impact of their implementation on aquatic contamination. Our goals are to study the whistle-blowers, the risk perception of consumers linked with their practices, and the contamination in parabens and their substitutes, triclosan, and triclocarban from wastewater to surface water. The project investigates the following potential solutions: modifications of industrial formulation or changes in consumption practices. The final purpose is to provide policy instruments for local authorities aiming at building effective strategies to fight against micropollutants in receiving waters.

  1. The Screw Blower Use for Save Energy%螺杆风机的节能改造

    Institute of Scientific and Technical Information of China (English)

    梁恒伟

    2015-01-01

    本文通过对负责单位污水处理车间改造螺杆风机为变频器控制,较好地使设备运转更平稳,降低了用电及维护费用,同时减少了单位生产成本,提高了设备的运行效率,响应了当今节能降耗的号召。%To change screw blower controlling and save electric cost for the company waste water treatment Plant.It is improve to screw blower use efficient as well as responded to the call of saving energy and reducing consumption today.

  2. Novel design for transparent high-pressure fuel injector nozzles

    Science.gov (United States)

    Falgout, Z.; Linne, M.

    2016-08-01

    The efficiency and emissions of internal combustion (IC) engines are closely tied to the formation of the combustible air-fuel mixture. Direct-injection engines have become more common due to their increased practical flexibility and efficiency, and sprays dominate mixture formation in these engines. Spray formation, or rather the transition from a cylindrical liquid jet to a field of isolated droplets, is not completely understood. However, it is known that nozzle orifice flow and cavitation have an important effect on the formation of fuel injector sprays, even if the exact details of this effect remain unknown. A number of studies in recent years have used injectors with optically transparent nozzles (OTN) to allow observation of the nozzle orifice flow. Our goal in this work is to design various OTN concepts that mimic the flow inside commercial injector nozzles, at realistic fuel pressures, and yet still allow access to the very near nozzle region of the spray so that interior flow structure can be correlated with primary breakup dynamics. This goal has not been achieved until now because interior structures can be very complex, and the most appropriate optical materials are brittle and easily fractured by realistic fuel pressures. An OTN design that achieves realistic injection pressures and grants visual access to the interior flow and spray formation will be explained in detail. The design uses an acrylic nozzle, which is ideal for imaging the interior flow. This nozzle is supported from the outside with sapphire clamps, which reduces tensile stresses in the nozzle and increases the nozzle's injection pressure capacity. An ensemble of nozzles were mechanically tested to prove this design concept.

  3. Continuous boiler cleaning with explosion generators. The alternative to soot blowers; Heizflaechenabreinigung mit Explosionsgeneratoren. Die Alternative zu Russblaesern

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, Christian; Rueegg, Hans [Explosion Power GmbH, Lenzburg (Switzerland); Pajarskas, Arno [Explosion Power DE GmbH, Duesseldorf (Germany)

    2011-07-01

    The explosion generator was recently developed by Explosion Power GmbH. With explosion generators, the boiler is cleaned by pressure waves, which are created by controlled gas explosions of natural gas and oxygen. The experience of 22 months of operation in the WtE plant in Lucerne shows that the cleaning efficiency of the explosion generators is much higher than that of soot blowers. Explosion generators are installed Europe-wide in more than 13 different boiler lines. (orig.)

  4. Cosmet'eau -Changes in the personal care product consumption practices: from whistle-blowers to impacts on aquatic environments

    OpenAIRE

    Bressy, Adèle; Carré, Catherine; Caupos, Émilie; Gouvello, Bernard de; Deroubaix, José-Frédéric; Deutsch, Jean-Claude; Mailler, Romain; Marconi, Anthony; Neveu, Pascale; Paulic, Laurent; Pichon, Sébastien; Rocher, Vincent; Severin, Irina; SOYER, Mathilde; Moilleron, Régis

    2016-01-01

    International audience; The Cosmet'eau project (2015-2018) investigates the " changes in the personal care product (PCP) consumption practices: from whistle-blowers to impacts on aquatic environments. " In this project, the example of PCPs will be used to understand how public health concerns related to micropollutants can be addressed by public authorities – including local authorities –, industries and consumers. The project aims to characterize the possible changes in PCP consumption pract...

  5. Effects of inlet radius and bell mouth radius on flow rate and sound quality of centrifugal blower

    Energy Technology Data Exchange (ETDEWEB)

    Son, Pham Ngoc; Kim, Jae Won; Byun, S. M. [Sunmoon University, Asan (Korea, Republic of); Ahn, E. Y. [Hanbat National University, Daejeon (Korea, Republic of)

    2012-05-15

    The effect of inlet radius and bell mouth radius on flow rate of centrifugal blower were numerically simulated using a commercial CFD program, FLUENT. In this research, a total of eight numerical models were prepared by combining different values of bell mouth radii and inlet radii (the cross section of bell mouth was chosen as a circular arc in this research). The frozen rotor method combined with a realizable k-epsilon turbulence model and non-equilibrium wall function was used to simulate the three-dimensional flow inside the centrifugal blowers. The inlet radius was then revealed to have significant impact on flow rate with the maximum difference between analyzed models was about 4.5% while the bell mouth radius had about 3% impact on flow rate. Parallel experiments were carried out to confirm the results of CFD analysis. The CFD results were thereafter validated owning to the good agreement between CFD results and the parallel experiment results. In addition to performance analysis, noise experiments were carried out to analyze the dependence of sound quality on inlet radius and bell mouth radius with different flow rate. The noise experiment results showed that the loudness and sharpness value of different models were quite similar, which mean the inlet radius and the bell mouth radius didn't have a clear impact on sound quality of centrifugal blower.

  6. Safety demonstration tests on pressure rise in ventilation system and blower integrity of a fuel-reprocessing plant

    Energy Technology Data Exchange (ETDEWEB)

    Takada, Junichi; Suzuki, Motoe; Tsukamoto, Michio; Koike, Tadao; Nishio, Gunji [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-12-01

    In JAERI, the demonstration test was carried out as a part of safety researches of the fuel-reprocessing plant using a large-scale facility consist of cells, ducts, dumpers, HEPA filters and a blower, when an explosive burning due to a rapid reaction of thermal decomposition for solvent/nitric acid occurs in a cell of the reprocessing plant. In the demonstration test, pressure response propagating through the facility was measured under a blowing of air from a pressurized tank into the cell in the facility to elucidate an influence of pressure rise in the ventilation system. Consequently, effective pressure decrease in the facility was given by a configuration of cells and ducts in the facility. In the test, transient responses of HEPA filters and the blower by the blowing of air were also measured to confirm the integrity. So that, it is confirmed that HEPA filters and the blower under pressure loading were sufficient to maintain the integrity. The content described in this report will contribute to safety assessment of the ventilation system in the event of explosive burning in the reprocessing plant. (author)

  7. Investigation of convergent-divergent nozzles applicable to reduced-power supersonic cruise aircraft

    Science.gov (United States)

    Berrier, B. L.; Re, R. J.

    1980-01-01

    An investigation was conducted of isolated convergent-divergent nozzles to determine the effect of several design parameters on nozzle performance. Tests were conducted using high pressure air for propulsion simulation at Mach numbers from 0.60 to 2.86 at an angle of attack of 0 deg and at nozzle pressure ratios from jet off to 46.0. Three power settings (dry, partial afterburning, and maximum afterburning), three nozzle lengths, and nozzle expansion ratios from 1.22 to 2.24 were investigated. In addition, the effects of nozzle throat radius and a cusp in the external boattail geometry were studied. The results of this study indicate that, for nozzles operating near design conditions, increasing nozzle length increases nozzle thrust-minus-drag performance. Nozzle throat radius and an external boattail cusp had negligible effects on nozzle drag or internal performance.

  8. Ubi Materia, Ibi Geometria

    Science.gov (United States)

    2000-09-29

    ideal on the other, caused probably certain tension for Kepler during his later studies. Primamn contrarietatem Aristoteles in metaphysicis recipit itlam...quam ex materia aut occasione materiae, aut uidi materia, tbi geometrra. Itaque quam Aristoteles dixit primam con trarietatem sine medio inter idem et... Aristoteles .7 For example, in his study of the snowflake (Strena seu de Nine sexangula ([10]) ,s Kepler searches the reason and cause for the sixfold

  9. Feedback mechanism for smart nozzles and nebulizers

    Science.gov (United States)

    Montaser, Akbar [Potomac, MD; Jorabchi, Kaveh [Arlington, VA; Kahen, Kaveh [Kleinburg, CA

    2009-01-27

    Nozzles and nebulizers able to produce aerosol with optimum and reproducible quality based on feedback information obtained using laser imaging techniques. Two laser-based imaging techniques based on particle image velocimetry (PTV) and optical patternation map and contrast size and velocity distributions for indirect and direct pneumatic nebulizations in plasma spectrometry. Two pulses from thin laser sheet with known time difference illuminate droplets flow field. Charge coupled device (CCL)) captures scattering of laser light from droplets, providing two instantaneous particle images. Pointwise cross-correlation of corresponding images yields two-dimensional velocity map of aerosol velocity field. For droplet size distribution studies, solution is doped with fluorescent dye and both laser induced florescence (LIF) and Mie scattering images are captured simultaneously by two CCDs with the same field of view. Ratio of LIF/Mie images provides relative droplet size information, then scaled by point calibration method via phase Doppler particle analyzer.

  10. Transient performance characteristics of uncontrolled and controlled ventilation systems with a single blower, two blowers connected in parallel, or two blowers connected in series; Das instationaere Betriebsverhalten ungeregelter und geregelter lufttechnischer Anlagen mit einem, zwei in Reihe oder zwei parallelgeschalteten Ventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Schulze Dieckhoff, B.

    1999-07-01

    Transient performance characteristics of uncontrolled and controlled ventilation systems with single blowers and blowers connected in series and in parallel are investigated. The model comprises mathematical models of transient, frictional and one-dimensional flow in the plant components. The pipeline component is modelled using so-called distributed parameters. The controller assumed in the model is a randomly parametrizable PID controller. The effects of time-dependent controlled controller actions are investigated to begin with in order to identify global system instabilities. An important class of flow-linduced instabilities are continuous, self-excited pressure and mass flow pulsations (pumping) or, in case of blowers connected in parallel, periodic alternating blower volume increase (oscillation). These two types of oscillation are based on fundamentally different, nonlinear physical mechanisms. Control of pressures and mass flow in ventilation systems is investigated, e.g. by analyzing controller-induced oscillations. [German] Es wird das instationaere Betriebsverhalten ungeregelter und geregelter lufttechnischer Anlagen mit Ventilatoren in Einzelanordnung, Reihen- und Parallelschaltung untersucht. Wesentliche Elemente des Rechenmodells sind mathematische Modelle fuer die instationaere, reibungsbehaftete und eindimensionale Stroemung in den Anlagenkomponenten. Die Komponente 'Rohrleitung' ist mit sog. verteilten Parametern modelliert. Als Regler ist ein beliebig parametrierbarer PID-Regler modelliert. Zunaechst werden die Auswirkungen zeitabhaengiger, gesteuerter Stelleingriffe untersucht. Ein wesentliches Ergebnis ist die Identifikation globaler Systeminstabilitaeten. Eine wichtige Klasse stroemungsbedingter Instabilitaeten sind kontinuierliche, selbsterregte Druck- und Massenstrompulsationen (Pumpen) oder, bei parallelgeschalteten Ventilatoren, eine periodische, wechselweise Mehrfoerderung der Ventilatoren (Pendeln). Diesen beiden

  11. Serrating Nozzle Surfaces for Complete Transfer of Droplets

    Science.gov (United States)

    Kim, Chang-Jin " CJ" Yi, Uichong

    2010-01-01

    A method of ensuring the complete transfer of liquid droplets from nozzles in microfluidic devices to nearby surfaces involves relatively simple geometric modification of the nozzle surfaces. The method is especially applicable to nozzles in print heads and similar devices required to dispense liquid droplets having precise volumes. Examples of such devices include heads for soft printing of ink on paper and heads for depositing droplets of deoxyribonucleic acid (DNA) or protein solutions on glass plates to form microarrays of spots for analysis. The main purpose served by the present method is to ensure that droplets transferred from a nozzle have consistent volume, as needed to ensure accuracy in microarray analysis or consistent appearance of printed text and images. In soft printing, droplets having consistent volume are generated inside a print head, but in the absence of the present method, the consistency is lost in printing because after each printing action (in which a drop is ejected from a nozzle), a small residual volume of liquid remains attached to the nozzle. By providing for complete transfer of droplets (and thus eliminating residual liquid attached to the nozzle) the method ensures consistency of volume of transferred droplets. An additional benefit of elimination of residue is prevention of cross-contamination among different liquids printed through the same nozzle a major consideration in DNA microarray analysis. The method also accelerates the printing process by minimizing the need to clean a printing head to prevent cross-contamination. Soft printing involves a hydrophobic nozzle surface and a hydrophilic print surface. When the two surfaces are brought into proximity such that a droplet in the nozzle makes contact with the print surface, a substantial portion of the droplet becomes transferred to the print surface. Then as the nozzle and the print surface are pulled apart, the droplet is pulled apart and most of the droplet remains on the

  12. Application of LBB to a nozzle-pipe interface

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Y.J.; Sohn, G.H.; Kim, Y.J. [and others

    1997-04-01

    Typical LBB (Leak-Before-Break) analysis is performed for the highest stress location for each different type of material in the high energy pipe line. In most cases, the highest stress occurs at the nozzle and pipe interface location at the terminal end. The standard finite element analysis approach to calculate J-Integral values at the crack tip utilizes symmetry conditions when modeling near the nozzle as well as away from the nozzle region to minimize the model size and simplify the calculation of J-integral values at the crack tip. A factor of two is typically applied to the J-integral value to account for symmetric conditions. This simplified analysis can lead to conservative results especially for small diameter pipes where the asymmetry of the nozzle-pipe interface is ignored. The stiffness of the residual piping system and non-symmetries of geometry along with different material for the nozzle, safe end and pipe are usually omitted in current LBB methodology. In this paper, the effects of non-symmetries due to geometry and material at the pipe-nozzle interface are presented. Various LBB analyses are performed for a small diameter piping system to evaluate the effect a nozzle has on the J-integral calculation, crack opening area and crack stability. In addition, material differences between the nozzle and pipe are evaluated. Comparison is made between a pipe model and a nozzle-pipe interface model, and a LBB PED (Piping Evaluation Diagram) curve is developed to summarize the results for use by piping designers.

  13. Effusive Atomic Oven Nozzle Design Using a Microcapillary Array

    CERN Document Server

    Senaratne, Ruwan; Geiger, Zachary A; Fujiwara, Kurt M; Lebedev, Vyacheslav; Weld, David M

    2014-01-01

    We present a simple and inexpensive design for a multichannel effusive oven nozzle which provides improved atomic beam collimation and thus extended oven lifetimes. Using this design we demonstrate an atomic lithium source suitable for trapped-atom experiments. At a nozzle temperature of 525$^{\\circ}$C the total atomic beam flux directly after the nozzle is $1.2 \\times 10^{14}$ atoms per second with a peak beam intensity greater than $5.0 \\times 10^{16}$ atoms per second per steradian. This suggests an oven lifetime of several centuries of continuous operation.

  14. Simple and Compact Nozzle Design for Laser Vaporization Sources

    CERN Document Server

    Kokish, M G; Odom, B C

    2015-01-01

    We have developed and implemented a compact transparent nozzle for use in laser vaporization sources. This nozzle eliminates the need for an ablation aperture, allowing for a more intense molecular beam. We use this nozzle to prepare a molecular beam of aluminum monohydride (AlH) suitable for ion trap loading of AlH$^+$ via photoionization in ultra-high vacuum. We demonstrate stable AlH production over hour time scales using a liquid ablation target. The long-term stability, low heat load and fast ion production rate of this source are well-suited to molecular ion experiments employing destructive state readout schemes requiring frequent trap reloading.

  15. Probabilistic assessment of space nuclear propulsion system nozzle

    Science.gov (United States)

    Shah, Ashwin R.; Ball, Richard D.; Chamis, Christos C.

    1994-01-01

    In assessing the reliability of a space nuclear propulsion system (SNPS) nozzle, uncertainties associated with the following design parameters were considered: geometry, boundary conditions, material behavior, and thermal and pressure loads. A preliminary assessment of the reliability was performed using NESSUS (Numerical Evaluation of Stochastic Structures Under Stress), a finite-element computer code developed at the NASA Lewis Research Center. The sensitivity of the nozzle reliability to the uncertainties in the random variables was quantified. With respect to the effective stress, preliminary results showed that the nozzle spatial geometry uncertainties have the most significant effect at low probabilities whereas the inner wall temperature has the most significant effect at higher probabilities.

  16. A review on nozzle wear in abrasive water jet machining application

    Science.gov (United States)

    Syazwani, H.; Mebrahitom, G.; Azmir, A.

    2016-02-01

    This paper discusses a review on nozzle wear in abrasive water jet machining application. Wear of the nozzle becomes a major problem since it may affect the water jet machining performance. Design, materials, and life of the nozzle give significance effect to the nozzle wear. There are various parameters that may influence the wear rate of the nozzle such as nozzle length, nozzle inlet angle, nozzle diameter, orifice diameter, abrasive flow rate and water pressure. The wear rate of the nozzle can be minimized by controlling these parameters. The mechanism of wear in the nozzle is similar to other traditional machining processes which uses a cutting tool. The high pressure of the water and hard abrasive particles may erode the nozzle wall. A new nozzle using a tungsten carbide-based material has been developed to reduce the wear rate and improve the nozzle life. Apart from that, prevention of the nozzle wear has been achieved using porous lubricated nozzle. This paper presents a comprehensive review about the wear of abrasive water jet nozzle.

  17. Design requirements to magnetic bearings for primary circuit blowers of high-temperature reactors. Final report; Auslegungsanforderungen an Magnetlager fuer Primaerkuehlgasgeblaese von Hochtemperaturreaktoren. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    1992-02-12

    To study the operational behaviour of blower shafts with magnetic bearings, a modular computer model was set up based on model laws, which permits to simulate shaft behaviour during dynamic loads acting on the blower shaft. During simulation runs, essential properties of position regulation (guide behaviour, secondary behaviour, and fault behaviour), and the behaviour of the blower shaft in the event of failure of a final stage of magnetic bearing electronics, with not-single-failure-proof and with failure-tolerant design of the final stages, as well as the effects of mechanical vibrations, e.g. as a result of earthquakes, on the behaviour of blower shafts were investigated. In order to transfer the results of the catch bearing tests to other designs of blowers with a vertical blower shaft, transmission laws and procedures were derived from theoretical considerations and from a dimension analysis which, however, could not be verified by means of tests. Application of the test results to horizontally placed blower shafts is possible only in part. The computer simulation model set up for the behaviour of the blower shafts is applicable without significant limitations to other blower shaft arrangements. (orig.). [Deutsch] Zur Untersuchung des Betriebsverhaltens magnetisch gelagerter Geblaesewellen wurde anhand von Modellgesetzen ein modulares Rechenmodell aufgebaut, das die Simulation des Wellenverhaltens bei auf die Geblaesewelle wirkenden dynamischen Belastungen erlaubt. In Simulationslaeufen wurden wesentliche Eigenschaften der Lageregelung (Fuehrungsverhalten, Folgeverhalten und Stoerungsverhalten) und das Verhalten der Geblaesewellen bei Ausfall einer Endstufe der Magnetlagerelektronik bei nicht einzelfehlersicherer und bei fehlertoleranter Ausfuehrung der Endstufen sowie die Auswirkungen mechanischer Erschuetterungen z.B. infolge von Erdbeben auf das Verhalten der Geblaesewelle untersucht. Zur Uebertragung der Ergebnisse der Fanglagerversuche auf andere

  18. Testicular cancer trends as 'whistle blowers' of testicular developmental problems in populations.

    Science.gov (United States)

    Skakkebaek, N E; Rajpert-De Meyts, E; Jørgensen, N; Main, K M; Leffers, H; Andersson, A-M; Juul, A; Jensen, T K; Toppari, J

    2007-08-01

    Recently a worldwide rise in the incidence of testicular germ cell cancer (TGCC) has been repeatedly reported. The changing disease pattern may signal that other testicular problems may also be increasing. We have reviewed recent research progress, in particular evidence gathered in the Nordic countries, which shows strong associations between testicular cancer, undescended testis, hypospadias, poor testicular development and function, and male infertility. These studies have led us to suggest the existence of a testicular dysgenesis syndrome (TDS), of which TGCC, undescended testis, hypospadias/disorders of sex differentiation and male fertility problems may be symptoms with varying penetration. In spite of their fetal origin, most of the TDS symptoms, including TGCC and poor semen quality, can only be diagnosed in adulthood. Data from a Danish-Finnish research collaboration strongly suggest that trends in TGCC rates of a population may be 'whistle blowers' of other reproductive health problems. As cancer registries are often of excellent quality - in contrast to registries for congenital abnormalities - health authorities should consider an increase in TGCC as a warning that other reproductive health problems may also be rising.

  19. Effect of Inlet Clearance on the Aerodynamic Performance of a Centrifugal Blower

    Science.gov (United States)

    Hariharan, C.; Govardhan, M.

    2016-09-01

    The present work reports the effect of inlet clearance on the performance of a centrifugal blower, with parallel wall volute, over its full operating range. For a particular impeller configuration, four volutes based on constant angular momentum principle, have been designed and analysed numerically for varying inlet clearances ranging from 0 mm (ideal clearance) to 5 mm. The computational methodology is validated using experimental data. The results indicate that as the clearance increases, the impeller performance in terms of both static and total pressure rise deteriorate. Further, the stage performances deteriorate in terms of efficiency and specific work for all mass flow rates. However, the performance of volute improves at lower mass flow rates compared to the Best Efficiency Point (BEP). A set of correlations have been developed to predict the change in stage performance as a function of clearance ratio. The non-dimensional values of change in specific work, isentropic efficiency and static pressure are found to be same irrespective of the shape of the volute.

  20. Blower/air cooler with internally finned tubes; Ventilator-Luftkuehler mit innenberippten Rohren

    Energy Technology Data Exchange (ETDEWEB)

    Arnemann, M. [FKU - Forschungszentrum fuer Kaelte- und Umwelttechnik, Berlin (Germany)

    1997-12-31

    Heat transfer is higher in finned tubes than in smooth tubes. In order to assess the extent of improvement, internal heat tranfer coefficients and pressure losses of smooth and finned tubes were investigated on behalf of Walter Roller GmbH and Co. Two blower-type air coolers of identical design (except for the tubes) were investigated in a calorimeter using R22 and different refrigerant mass flows, evaporation temperatures and air temperatures. The results are the basis for new develoments by Walter Roller. Energetic assessment of the new type of evaporator was made on the basis of the DIN 8955 and ENV 328 standards. The results and findings are presented. (orig.) [Deutsch] Der Einsatz von innenberippten Rohren laesst im Vergleich mit glatten Rohren einen deutlich verbesserten inneren Waermeuebergang erwarten. Zur Abschaetzung der Groessenordnung dieser Verbesserungen wurden im Auftrag der Firma Walter Roller GmbH and Co. die inneren Waermeuebergangskoeffizienten und die Druckverluste von glatten und innenberippten Rohren experimentell bestimmt. Dazu wurden zwei bis auf die Rohre baugleiche Ventilator-Luftkuehler ineinem Kalorimeter untersucht. Mit dem Kaeltemittel R22 wurden fuer verschiedene Kaeltemittelmassenstroeme, Verdampfungstemperaturen und Lufttemperaturen die Kennzahlen bestimmt, die zur Charakterisierung der Rohre dienlich sind. Die Ergebnisse bildeten die Grundlage fuer eine Neuentwicklung im Hause Walter Roller. Die energetische Bewertung des neuen Verdampfertyps erfolgte in Anlehnung an die Normen DIN 8955 bzw. ENV 328. Die Untersuchungen und die Ergebnisse werden praesentiert. (orig.)

  1. A noninvasive high frequency oscillation ventilator: Achieved by utilizing a blower and a valve.

    Science.gov (United States)

    Yuan, YueYang; Sun, JianGuo; Wang, Baicun; Feng, Pei; Yang, ChongChang

    2016-02-01

    After the High Frequency Oscillatory Ventilation (HFOV) has been applied in the invasive ventilator, the new technique of noninvasive High Frequency Oscillatory Ventilation (nHFOV) which does not require opening the patient's airway has attracted much attention from the field. This paper proposes the design of an experimental positive pressure-controlled nHFOV ventilator which utilizes a blower and a special valve and has three ventilation modes: spontaneous controlled ventilation combining HFOV, time-cycled ventilation combining HFOV (T-HFOV), and continuous positive airway pressure ventilation combining HFOV. Experiments on respiratory model are conducted and demonstrated the feasibility of using nHFOV through the control of fan and valve. The experimental ventilator is able to produce an air flow with small tidal volume (VT) and a large minute ventilation volume (MV) using regular breath tubes and nasal mask (e.g., under T-HFOV mode, with a maximum tidal volume of 100 ml, the minute ventilation volume reached 14,400 ml). In the process of transmission, there is only a minor loss of oscillation pressure. (Under experimental condition and with an oscillation frequency of 2-10 Hz, peak pressure loss was around 0%-50% when it reaches the mask.).

  2. Condition Monitoring of Forward Curved Centrifugal Blower Using Coast Down Time Analysis

    Directory of Open Access Journals (Sweden)

    G. R. Rameshkumar

    2010-01-01

    Full Text Available Mechanical malfunctions such as, rotor unbalance and shaft misalignment are the most common causes of vibration in rotating machineries. Vibration is the most widely used parameter to monitor and asses the machine health condition. In this work, the Coast Down Time (CDT, which is an indicator of faults, is used to assess the condition of the rotating machine as a condition monitoring parameter. CDT is the total time taken by the system to dissipate the momentum acquired during sustained operation. Extensive experiments were conducted on Forward Curved Centrifugal Blower Test Rig at selected cutoff speeds for several combinations of combined horizontal and vertical parallel misalignment, combined parallel and angular misalignment, as well as for various unbalance conditions. As mechanical faults increase, a drastic decrease in CDT is found and this is represented as CDT reduction percentage. A specific correlation between the CDT reduction percentage, level of mechanical faults, and rotational cutoff speeds is observed. The results are analyzed and compared with vibration analysis for potential use of CDT as one of the condition monitoring parameter.

  3. Enhancement of Nutrient Removal in a Hybrid Constructed Wetland Utilizing an Electric Fan Air Blower with Renewable Energy of Solar and Wind Power

    Directory of Open Access Journals (Sweden)

    Dong Jin Lee

    2015-01-01

    Full Text Available The sewage treatment efficiency of hybrid constructed wetlands (CWs was evaluated under different ventilation methods. The removal efficiencies of biochemical oxygen demand (BOD, total nitrogen (TN, and total phosphorus (TP in the vertical flow- (VF- horizontal flow (HF CWs using an electric fan air blower by the renewable energy of solar and wind power were higher than those by natural ventilation, excluding only suspended solids (SS. The TN treatment efficiency in the CW using the air blower especially increased rapidly by 16.6% in comparison with the CW employing natural ventilation, since the VF bed provided suitable conditions (aerobic for nitrification to occur. The average removal efficiencies of BOD, SS, TN, and TP in the effluent were 98.8, 97.4, 58.0, and 48.3% in the CW using an electric fan air blower, respectively. The treatment performance of the CWs under different ventilation methods was assessed, showing TN in the CW using an electric fan air blower to be reduced by 57.5~58.6% for inlet TN loading, whereas reduction by 19.0~53.3% was observed in the CW with natural ventilation. Therefore, to increase the removal of nutrients in CWs, an improved ventilation system, providing ventilation via an electric fan air blower with the renewable energy, is recommended.

  4. Flashback detection sensor for lean premix fuel nozzles

    Science.gov (United States)

    Thornton, Jimmy Dean; Richards, George Alan; Straub, Douglas L.; Liese, Eric Arnold; Trader, Jr., John Lee; Fasching, George Edward

    2002-08-06

    A sensor for detecting the flame occurring during a flashback condition in the fuel nozzle of a lean premix combustion system is presented. The sensor comprises an electrically isolated flashback detection electrode and a guard electrode, both of which generate electrical fields extending to the walls of the combustion chamber and to the walls of the fuel nozzle. The sensor is positioned on the fuel nozzle center body at a location proximate the entrance to the combustion chamber of the gas turbine combustion system. The sensor provides 360.degree. detection of a flashback inside the fuel nozzle, by detecting the current conducted by the flame within a time frame that will prevent damage to the gas turbine combustion system caused by the flashback condition.

  5. Noise Characteristics of Overexpanded Jets from Convergent-Divergent Nozzles

    Science.gov (United States)

    Zaman, K. B. M. Q.

    2008-01-01

    A broadband noise component occurring in the overexpanded flow regime with convergent-divergent nozzles is identified. Relative to a convergent nozzle, at same pressure ratios, this excess noise can lead to a large increase in the overall sound pressure levels. Several features distinguish it from the more familiar broadband shock associated noise. Unlike the latter, it is observed even at shallow polar locations and there is no noticeable shift of the spectral content in frequency with observation angle. The amplitudes are found to be more pronounced with nozzles having larger half-angle of the divergent section. The noise apparently occurs when a shock resides within the divergent section of the nozzle and results from random unsteady motion of the shock.

  6. An evaluation of nozzle afterbody code - AR02P

    Science.gov (United States)

    Guyton, F. C.

    1986-07-01

    A project was undertaken to develop a computational fluid dynamics (CFD) code for use in nozzle afterbody analysis. Objectives were to create a three-dimensional code capable of calculating afterbody flows with accuracy quantitatively close to the Navier-Stokes solutions, but which would use significantly fewer computer resources. The resulting program coupled an inverse boundary-layer routine with an Euler code and incorporated a jet plume. Calculations were made for the axisymmetric AGARD 15-deg boattail afterbody with variations in nozzle pressure ratio for Mach numbers 0.6 and 0.9, and compared with experimental results. The code predicted drag changes with NPR which showed the proper variations, but the code did not provide the accuracy required for typical nozzle afterbody analysis. (NPR = Nozzle total pressure to free stream static pressure ratio.)

  7. Design of a continuously variable Mach-number nozzle

    Institute of Scientific and Technical Information of China (English)

    郭善广; 王振国; 赵玉新

    2015-01-01

    A design method was developed to specify the profile of the continuously variable Mach-number nozzle for the supersonic wind tunnel. The controllable contour design technique was applied to obtaining the original nozzle profile, while other Mach- numbers were derived from the transformation of the original profile. A design scheme, covering a Mach-number range of 3.0nozzle. The computed results indicate that exit uniform flow is obtained with 1.19% of the maximal Mach-number deviation at the nozzle exit. The present design method achieves the continuously variable Mach-number flow during a wind tunnel running.

  8. Optimal Thrust Vectoring for an Annular Aerospike Nozzle Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Recent success of an annular aerospike flight test by NASA Dryden has prompted keen interest in providing thrust vector capability to the annular aerospike nozzle...

  9. Altitude Compensating Nozzle Transonic Performance Flight Demonstration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Altitude compensating nozzles continue to be of interest for use on future launch vehicle boosters and upper stages because of their higher mission average Isp and...

  10. Characteristics of Multiplexed Grooved Nozzles for High Flow Rate Electrospray

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyoung Tae; Kim, Woo Jin; Kim, Sang Soo [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2007-10-15

    The electrospray operated in the cone-jet mode can generate highly charged micro droplets in an almost uniform size at flow rates. Therefore, the multiplexing system which can retain the characteristics of the cone-jet mode is inevitable for the electrospray application. This experiment reports the multiplexed grooved nozzle system with the extractor. The effects of the grooves and the extractor on the performance of the electrospray were evaluated through experiments. Using the grooved nozzle, the stable cone-jet mode can be achieved at the each groove in the grooved mode. Furthermore, the number of nozzles per unit area is increased by the extractor. The multiplexing density is 12 jets per cm{sup 2} at 30 mm distance from the nozzle tip to the ground plate. The multiplexing system for the high flow rate electrospray is realized with the extractor which can diminish the space charge effect without sacrificing characteristics of the cone-jet mode.

  11. Improvement of Flow Quality in NAL Chofu Mach 10 Nozzle

    Science.gov (United States)

    Lacey, John; Inoue, Yasutoshi; Higashida, Akio; Inoue, Manabu; Ishizaka, Kouichi; Korte, John J.

    2002-01-01

    As a result of CFD analysis and remachining of the nozzle, the flow quality of the Mach 10 Hypersonic Wind Tunnel at NAL Chofu, Japan was improved. The subsequent test results validated the CFD analytical predictions by NASA and MHL.

  12. Feasibility evaluation of the monolithic braided ablative nozzle

    Science.gov (United States)

    Director, Mark N.; McPherson, Douglass J., Sr.

    1992-02-01

    The feasibility of the monolithic braided ablative nozzle was evaluated as part of an independent research and development (IR&D) program complementary to the National Aeronautics and Space Administration/Marshall Space Flight Center (NASA/MSFC) Low-Cost, High-Reliability Case, Insulation and Nozzle for Large Solid Rocket Motors (LOCCIN) Program. The monolithic braided ablative nozzle is a new concept that utilizes a continuous, ablative, monolithic flame surface that extends from the nozzle entrance, through the throat, to the exit plane. The flame surface is fabricated using a Through-the-Thickness braided carbon-fiber preform, which is impregnated with a phenolic or phenolic-like resin. During operation, the braided-carbon fiber/resin material ablates, leaving the structural backside at temperatures which are sufficiently low to preclude the need for any additional insulative materials. The monolithic braided nozzle derives its potential for low life cycle cost through the use of automated processing, one-component fabrication, low material scrap, low process scrap, inexpensive raw materials, and simplified case attachment. It also has the potential for high reliability because its construction prevents delamination, has no nozzle bondlines or leak paths along the flame surface, is amenable to simplified analysis, and is readily inspectable. In addition, the braided construction has inherent toughness and is damage-tolerant. Two static-firing tests were conducted using subscale, 1.8 - 2.0-inch throat diameter, hardware. Tests were approximately 15 seconds in duration, using a conventional 18 percent aluminum/ammonium perchlorate propellant. The first of these tests evaluated the braided ablative as an integral backside insulator and exit cone; the second test evaluated the monolithic braided ablative as an integral entrance/throat/exit cone nozzle. Both tests met their objectives. Radial ablation rates at the throat were as predicted, approximately 0.017 in

  13. Optimisation of acoustics and efficiency of axial blowers, e.g. in liquefiers or recirculation coolers; Optimierung der Akustik und der Effizienz von Axialventilatoren, die beispielsweise auf Verfluessigern und Rueckkuehlern eingesetzt werden

    Energy Technology Data Exchange (ETDEWEB)

    Dietle, J.; Neumeier, R. [Ziehl-Abegg AG, Kuenzelsau (Germany)

    2006-07-01

    Blowers are the main source of noise in air-cooled refrigerator components. The noise development mechanisms can be characterized as flow noise, mechanical noise and electrical noise, which are differentiated depending on the type of application. The optimisation of the blower and overall system is illustrated for different influencing factors. (orig.)

  14. Magnetic Nozzles for Plasma Thrusters: Acceleration, Thrust, and Detachment Mechanisms

    Science.gov (United States)

    2011-10-01

    A. Plasma flow layer features and Non - Maxwellian EEDF Essentially, a quasineutral steepening layer (QSL) is an electric potential fall of the order of...nozzle. It is needed to analyze the far beam. It requires a more sophisticated integration technique. 5. Plasma detachment via non -neutral...Magnetic nozzles for plasma thrusters: acceleration, thrust, and detachment mechanisms Eduardo Ahedo Mario Merino Plasmas and Space

  15. Jet-Engine Exhaust Nozzle With Thrust-Directing Flaps

    Science.gov (United States)

    Wing, David J.

    1996-01-01

    Convergent/divergent jet-engine exhaust nozzle has cruciform divergent passage containing flaps that move to deflect flow of exhaust in either or both planes perpendicular to main fore-and-aft axis of undeflected flow. Prototype of thrust-vector-control nozzles installed in advanced, high-performance airplanes to provide large pitching (usually, vertical) and yawing (usually, horizontal) attitude-control forces independent of attitude-control forces produced by usual aerodynamic control surfaces.

  16. Influences of Geometric Parameters upon Nozzle Performances in Scramjets

    Institute of Scientific and Technical Information of China (English)

    Li Jianping; Song Wenyan; Xing Ying; Luo Feiteng

    2008-01-01

    This article investigates and presents the influences of geomea'ic parameters of a scramjet exerting upon its nozzle performances. These parameters include divergent angles, total lengths, height ratios, cowl lengths, and cowl angles. The flow field within the scramjet nozzle is simulated numerically by using the CFD software--FLUENT in association with coupled implicit solver and an RNG k-ε tur-bulence model.

  17. Fluidic Control of Nozzle Flow: Some Performance Measurements

    Science.gov (United States)

    Federspiel, John; Bangert, Linda; Wing, David; Hawkes, Tim

    1995-01-01

    Results are presented of an experimental program that investigated the use of a secondary air stream to control the amount of flow through a convergent-divergent nozzle. These static tests utilized high pressure, ambient temperature air that was injected at the throat of the nozzle through an annular slot. Multiple injection slot sizes and injection angles were tested. The introduction of secondary flow was made in an opposing direction to the primary flow and the resulting flow field caused the primary stream to react as though the physical throat size had been reduced. The percentage reduction in primary flow rate was generally about twice the injected flow rate. The most effective throttling was achieved by injecting through the smallest slot in an orientation most nearly opposed to the approaching primary flow. Thrust edliciency, as measured by changes in nozzle thrust coefficient, was highest at high nozzle pressure ratios, NPR. The static test results agreed with predictions obtained prior from PABSD, a fully viscous computational fluid dynamics program. Since use of such an injection system on gas turbine engine exhaust nozzles would be primarily at high NPRs, it was concluded that fluidic control holds promise for reducing nozzle weight and complexity on future systems.

  18. Effect of Tabs on a Rectangular Nozzle Studied

    Science.gov (United States)

    2005-01-01

    In a continuing research program, jets from nozzles of different geometries are being investigated with the aim of increasing mixing and spreading in those flows. Flow fields from nozzles with elliptic, rectangular, and other more complex cross-sectional shapes are being studied in comparison to circular nozzles over a wide Mach number range. As noted by previous researchers, noncircular jets usually spread faster than circular jets. Another technique being investigated to increase jet spreading even further for a given nozzle is the use of "tabs" to generate vortices. A typical tab is a triangular-shaped protrusion placed at the nozzle exit, with the base of the triangle touching the nozzle wall and the apex leaning downstream at 45 to the stream direction. This geometry was determined by a parametric study to produce the optimum effect for a given area blockage. The tabs can increase jet spreading significantly. The underlying mechanism traces to a pair of counter-rotating streamwise vortices originating from each tab. These vortex pairs persist in the flow; and with the appropriate number and strength, they can increase spreading.

  19. Nozzle Mounting Method Optimization Based on Robot Kinematic Analysis

    Science.gov (United States)

    Chen, Chaoyue; Liao, Hanlin; Montavon, Ghislain; Deng, Sihao

    2016-08-01

    Nowadays, the application of industrial robots in thermal spray is gaining more and more importance. A desired coating quality depends on factors such as a balanced robot performance, a uniform scanning trajectory and stable parameters (e.g. nozzle speed, scanning step, spray angle, standoff distance). These factors also affect the mass and heat transfer as well as the coating formation. Thus, the kinematic optimization of all these aspects plays a key role in order to obtain an optimal coating quality. In this study, the robot performance was optimized from the aspect of nozzle mounting on the robot. An optimized nozzle mounting for a type F4 nozzle was designed, based on the conventional mounting method from the point of view of robot kinematics validated on a virtual robot. Robot kinematic parameters were obtained from the simulation by offline programming software and analyzed by statistical methods. The energy consumptions of different nozzle mounting methods were also compared. The results showed that it was possible to reasonably assign the amount of robot motion to each axis during the process, so achieving a constant nozzle speed. Thus, it is possible optimize robot performance and to economize robot energy.

  20. Simulating radiative shocks in nozzle shock tubes

    CERN Document Server

    van der Holst, B; Sokolov, I V; Daldorff, L K S; Powell, K G; Drake, R P

    2011-01-01

    We use the recently developed Center for Radiative Shock Hydrodynamics (CRASH) code to numerically simulate laser-driven radiative shock experiments. These shocks are launched by an ablated beryllium disk and are driven down xenon-filled plastic tubes. The simulations are initialized by the two-dimensional version of the Lagrangian Hyades code which is used to evaluate the laser energy deposition during the first 1.1ns. The later times are calculated with the CRASH code. This code solves for the multi-material hydrodynamics with separate electron and ion temperatures on an Eulerian block-adaptive-mesh and includes a multi-group flux-limited radiation diffusion and electron thermal heat conduction. The goal of the present paper is to demonstrate the capability to simulate radiative shocks of essentially three-dimensional experimental configurations, such as circular and elliptical nozzles. We show that the compound shock structure of the primary and wall shock is captured and verify that the shock properties a...

  1. Application of transient numeric simulation methods for calculating aeroacoustic sources of noise in axial blowers; Anwendung von instationaeren numerischen Simulationsmethoden zur Berechnung aeroakustischer Schallquellen bei Axialventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Reese, H.

    2007-07-01

    The publication intends to contribute to the calculation of aeroacoustic noise of axial blowers. Using the example of a typical low-pressure axial blower, the transient flow field, aeroacoustic sound waves and noise emissions are calculated. Four methods of numeric flow simulation are used, each with a different degree of approximation. In order to investigate different noise development mechanisms, flow to the blower rotor was investigated in the undisturbed state and in a highly turbulent state. Low-frequency noise as a rule is dominated by mechanisms like secondary flow or turbulent inflow which can be predicted rather well by numeric simulations of medium accuracy. Higher-frequency noise resulting from the turbulent boundary layer can only be predicted by large eddy simulation, which is quite time-consuming. (orig.)

  2. Imergindo a Geometria Dinâmica em Sistemas de Educação a Distância: IGEOM e SAW

    Directory of Open Access Journals (Sweden)

    Leônidas de Oliveira Brandão

    2009-06-01

    Full Text Available Neste trabalho, apresentamos algumas novas funcionalidades desenvolvidas no programa para ensino-aprendizagem de Geometria, o iGeom. Também mostramos um novo sistema gerenciador de cursos pela Web, o SAW, e alguns benefícios trazidos por estes ambientes. Dentre os principais recursos desenvolvidos no iGeom, destacamos: a autoria e a avaliação automática de exercícios e a comunicação com servidores Web. Deste modo, professor e aluno obtém mais benefícios. O professor tem sua tarefa de avaliação de exercícios reduzida ou eliminada, enquanto o aluno, além de poder estudar em seu próprio ritmo, pode obter uma pronta resposta sobre como seu exercício foi avaliado. O iGeom já pode ser descarregado gratuitamente pela Web, e o SAW terá seu código disponibilizado ainda este ano.

  3. Geometria dinâmica na sala de aula: o desenvolvimento do futuro professor de matemática diante da imprevisibilidade

    Directory of Open Access Journals (Sweden)

    Guilherme Henrique Gomes da Silva

    2013-01-01

    Full Text Available Este artigo é baseado em resultados de uma pesquisa cujo objetivo foi analisar como futuros professores de matemática, vinculados a um grupo de estudos, se apropriaram de um software de geometria dinâmica, de forma a inseri-lo em atividades de ensino. O grupo se reuniu para ler e discutir artigos científicos, explorar um software e elaborar uma oficina para alunos do Ensino Médio. Aqui são discutidas reflexões do grupo sobre os imprevistos que podem ocorrer quando o professor atua num ambiente de aprendizagem baseado em Tecnologia da Informação e Comunicação (TIC. São apresentados episódios que ilustram como uma zona de risco pode se constituir numa zona de possibilidades para aprendizagem da docência. O grupo fornece estímulo e condições para se refletir e enfrentar os imprevistos decorrentes de um ambiente computacional, o que impulsiona o movimento para o desenvolvimento profissional.

  4. Potential of energy conservation in heating systems by means of blower convectors; Energieeinsparungspotential in Heizungsystemen durch den Einsatz von Geblaesekonvektoren

    Energy Technology Data Exchange (ETDEWEB)

    Binder, Andreas; Raisch, Ingo

    2011-07-01

    Blowers are used for heating in buildings, mostly under windows, in corners, or in niches. When heating systems are modernized, it is a useful strategy to reduce the flow temperature, but this means that the existing radiator is underdimensioned. A convective blower is presented that fits into most heating niches and provides the same capacity at lower water temperatures. Disadvantages are electric power consumption, higher noise, and faster soiling. Advantages are fast and comfortable room temperature control and the possibility of cooling. Theoretical assessments are made to investigate the potential savings resulting from convective blowers as well as their effects in terms of comfort and air quality. [German] In Gebaeuden werden zur Raumheizung in vielen Faellen Radiatoren eingesetzt. Diese werden beispielsweise unter Fenstern oder in Ecken platziert. Der Architekt sieht fuer den Einbau der Geraete oftmals eine Nische vor. Wird das komplette Heizungssystem saniert, ist es unter energetischen Gesichtspunkten sinnvoll die Vorlauftemperatur zu reduzieren. Der vorhandene Heizkoerper ist damit unterdimensioniert. Es wird ein Geblaesekonvektor entwickelt, der in eine Vielzahl der architektonisch ueblichen Heiznischen passt. Bei Abgabe der gleichen thermischen Leistung, ist es mit diesem Geraet moeglich die Heizung bei geringeren Wassertemperaturen zu betreiben. Die Beheizung von Raeumen mittels Konvektoren ist aber auch mit einigen Nachteilen behaftet, so wird elektrische Energie benoetigt, die Geraete emittieren Schall und neigen staerker zur Verschmutzung. Dem gegenueber stehen einige Vorteile wie einer schnelleren und komfortableren Regelung der Raumtemperatur und die Moeglichkeit zu Kuehlen. Es werden theoretische Abschaetzungen durchgefuehrt, wie gross das Einsparpotential durch Geblaesekonvektoren sein kann, und wie sich die Umstellung auf den Komfort, und die Luftqualitaet auswirkt.

  5. Automation of the control system and reform of the COSIPA no. 3 turbo blower; Automacao dos sistema de controle e reforma do turbo soprador n. 3 da Cosipa

    Energy Technology Data Exchange (ETDEWEB)

    Kobukloski, Sandro; Martins, Marcos Rogerio S.; Garcia, Jose Eduardo da S.; Reis, Joao de Paula; Romao Junior, Wilson; Vilarinho, Joao Clovis; Spinassi, Luiz Carlos; Florencio, Aurelio Freire; Rocha, Jose Olimpio Castro Pereira da [Companhia Siderurgica Paulista (COSIPA), Cubatao, SP (Brazil)

    2001-07-01

    The turbo blower no. 3 (TS no. 3) start operation in 1976 blowing for the COSIPA blast furnace no. 2. Since 1993 the equipment was dedicated to the blast furnace no. 1, which is smaller than the previous one, consequently releasing the excess air to the atmosphere. Due to some modifications and for safety of the equipment, an operational conditional has been introducing with higher energy consumption. Due to operational requests a complete machine control system reformation was decided, blower stator and rotor blade replacement, and installation of a self-cleaning pre-filtering system. (author)

  6. 高炉鼓风机的改造实践%Transformation of Blast Furnace Blower

    Institute of Scientific and Technical Information of China (English)

    陈庆凯; 赵健

    2001-01-01

    Transforming method of blast furnace blower is introduced,and main structural dimension after transformation is given. Comparison is carried out on each target before & after transformation. The obtaind economic benefits is described.%介绍了为提高流量的高炉鼓风机改造方案,给出了改造后的主要结构尺寸。对改造前后的各项指标做了对比,说明了取得的经济效益。

  7. Speed-controlled blowers reduce energy consumption in air conditioning systems; Drehzahlregulierte Luefter reduzieren Energieverbrauch einer Klimaanlage

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, W.

    1996-08-01

    Speed-controlled blower engines are described. The engines have four major advantages: Energy conservation and reduction of the operating cost; Variable air volume flow for optimum adaptation to varying operating conditions; Speed control reduces wear; Lower noise at lower speed (higher comfort). (HW) [Deutsch] Es werden drehzahlregulierte Lueftermotoren vorgestellt. Diese Motoren haben 4 wesentliche Vorteile - Energieeinsparung, Senkung der Betriebskosten - variabler Luftvolumenstrom bringt eine optimale Anpassung an die jeweiligen Betriebsbedingungen - eine moegliche Drehzahlreduzierung senkt den Verschleiss - kleinere Drehzahlen machen die Anlage leiser (Komfortverbesserung). (HW)

  8. Damage to soot blowers in a high dust DENOX plant. Schaeden an Russblaesern in einer High-dust-DENOX-Anlage

    Energy Technology Data Exchange (ETDEWEB)

    Bolte, C. (Kraftwerk Voerde, STEAG-RWE oHG (Germany)); Farwick, H. (Kraftwerk Voerde, STEAG-RWE oHG (Germany))

    1993-06-01

    The two 710 MW Units A and B at Voerde are equipped with selective catalytic reduction reactors in the high dust range. Following commissioning of the DENOX plant, the prescribed soot blowing conditions were proven to be adequate. About nine months later, the first operating problems occurred on the soot blowers and these intensified in the course of time. Following the failure of several steam supply pipes, the soot blowing then had to be adjusted to two-way since leaky blast valves became permeable to the condensate and dampening of the catalyser had to be feared. (orig.)

  9. Accurate measurement of air supply. Radial blower with a mass flow sensor; Fuer eine exakte Luftzuteilung. Radialgeblaese mit Massenstromsensor

    Energy Technology Data Exchange (ETDEWEB)

    Hartauer, Siegbert [ebm-papst Landshut GmbH, Landshut (Germany)

    2009-07-01

    Fire is alive, which has always made it an interesting object for interior decoration, e.g. open chimneys or chimneys with glass windows. Modern gas-fuelled chimneys combine the soothing vision of open flames with efficient room heating. For low pollution and low consumption, fire needs fuel and oxygen in an optimum ratio. Conventional ''atmospheric'' burners must be adjusted on site, but variations of temperature and atmospheric pressure will still vary the air supply. As an optimum alternative, the contribution presents a new radial blower with an integrated mass flow sensor. (orig.)

  10. Pressure drop and blower performance tests in very high temperature Helium Experimental LooP (HELP)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chan Soo; Hong, Sung Deok; Kim, Yong Wan [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    Korea Atomic Energy Research Institute (KAERI) has developed the gas loops to develop and verify the key components of the nuclear hydrogen production system. At the present, KAERI is operating a small scale gas loop for feasibility tests of process heat exchanger and a very high temperature Helium Experimental LooP (HELP) for verification tests of bench scale prototypes for high temperature key components in Very High Temperature gas cooled Reactor (VHTR). Figure 1 presents the HELP assembled with the key components. The size was designed for the verification test of a 150kW intermediate heat exchanger or the simulation test in a 1/6 scaled down fuel block. The loop consists of the primary loop and the secondary loop. The primary loop and the secondary loop simulate VHTR and intermediate loop in nuclear hydrogen production system, respectively. The loops were designed to withstand the maximum temperature of 1000 .Deg. C, the maximum pressure of 9.0 MPa, and the normal mass velocity of 0.5 kg/sec. The working fluid is helium as the actual coolant of VHTR. The primary loop is composed of a preheater, a high temperature heater, a hot gas duct, intermediate heat exchangers, a water cooled U tube heat exchanger, a gas bearing circulator, a passive venting system and gas filters. The secondary loop has the same system configuration as the primary loop except a high temperature heater. Two loops share a helium supply system, a helium purification system and the water loop for a cooling tower as Figure 2. In this study, the experimental results of the bypass line pressure drop and blower performance at the nitrogen condition are analyzed to predict the main line mass flow rates without heaters.

  11. Transient tests on blower trip and rod removal at the HTR-10

    Energy Technology Data Exchange (ETDEWEB)

    Hu Shouyin [Institute of Nuclear Energy Technology, Tsinghua University, P.O. Box 1021, Beijing 102201 (China)]. E-mail: hyyhtr@tsinghua.edu.cn; Wang Ruipian [Institute of Nuclear Energy Technology, Tsinghua University, P.O. Box 1021, Beijing 102201 (China); Gao Zuying [Institute of Nuclear Energy Technology, Tsinghua University, P.O. Box 1021, Beijing 102201 (China)

    2006-03-15

    Safety demonstration tests on the 10 MW high temperature gas-cooled reactor test module (HTR-10) were conducted to verify the inherent safety features of MHTGRs and to obtain the core and primary cooling system transient data for validation of safety analysis codes. Two simulated anticipated transients without scram (ATWS) tests, lose of forced cooling by trip of the helium blower and reactivity insertion via control rod withdrawal were performed. This paper describes the tests with detailed test method, condition and results. Calculated results show that the strongly negative temperature coefficient causes reactor power to closely follow heat removal levels. Maximum fuel temperature changes are limited by the large core heat capacity to below 1230 deg. C during two tests. The test of tripping the helium circulator ATWS test was conducted on October 15, 2003. Although none of 10 control rods was moved, the reactor power immediately decreased due to the negative temperature coefficient. After about 50 min, the reactor became criticality again. Finally, the reactor power went to a stable level with about 200 kW. The test of reactivity insertion ATWS test was conducted two times. Following the control rod withdrawal, the reactor power increased rapidly, the maximum power level reached to 5037 and 7230 kW from the initial power of 3000 kW in accordance with reactivity insertion of 0.136 and 0.689, respectively. After the reactivity introduced was compensated by means of the strong negative reactivity feedback effect, the reactor went to subcritical and the power decreased.

  12. Study on Characteristics of Different Types of Nozzles for Coal-Water Slurry Atomization

    Institute of Scientific and Technical Information of China (English)

    Kun Yuan; Lifang Chen; Chengkang Wu

    2001-01-01

    Three types of nozzles: a low-pressure multistage nozzle, an effervescent nozzle and a newly developed internal mixing air-blast nozzle, for atomization of Coal-Water Slurry (CWS) were investigated. Influence of CWS properties including surface tension and apparent viscosity on atomization was studied. Comparisons among the nozzles were carried out in terms of spray droplet mean diameter and fuel output. Versatility of each nozzle was investigated and atomization mechanism of each nozzle was analyzed as well. The results showed that the newly developed internal-mixing air-blast nozzle has high fuel output and small mean droplet size in the spray, but the multistage nozzle has high versatility for handling of low quality CWS.

  13. Parametric study of single expansion ramp nozzles at subsonic/transonic speeds

    Science.gov (United States)

    Capone, F. J.; Re, R. J.; Bare, E. A.; Maclean, M. K.

    1987-01-01

    The Langley Research Center has conducted a parametric investigation to determine the aeropropulsive characteristics of single expansion ramp nozzles (SERN). The SERN is a nonaxisymmetric, variable-area, internal/external expansion exhaust nozzle. Internal nozzle parameters that were varied included upper ramp length, ramp chordal angle, lower flap length, flap angle and the axial and vertical locations of nozzle throat. Convergent-divergent and convergent nozzles were included in this investigation which was conducted in the Langley 16-Foot Transonic Tunnel at Mach numbers from 0.6 to 1.2 and at nozzle pressure ratios up to 12.0.

  14. Influence of spray nozzle shape upon atomization process

    Science.gov (United States)

    Beniuga, Marius; Mihai, Ioan

    2016-12-01

    The atomization process is affected by a number of operating parameters (pressure, viscosity, temperature, etc.) [1-6] and the adopted constructive solution. In this article are compared parameters of atomized liquid jet with two nozzles that have different lifespan, one being new and the other one out. The last statement shows that the second nozzle was monitored as time of operation on the one hand and on the other hand, two dimensional nozzles have been analyzed using laser profilometry. To compare the experimental parameters was carried an experimental stand to change the period and pulse width in injecting liquid through two nozzles. Atomized liquid jets were photographed and filmed quickly. Images obtained were analyzed using a Matlab code that allowed to determine a number of parameters that characterize an atomized jet. Knowing the conditions and operating parameters of atomized jet, will establish a new wastewater nozzle block of parameter values that can be implemented in controller that provides dosing of the liquid injected. Experimental measurements to observe the myriad forms of atomized droplets to a wide range of operating conditions, realized using the electronic control module.

  15. CFD calculations in high-performance blower design; Einsatz von CFD-Berechnungen bei der Auslegung von Hochleistungsgeblaesen

    Energy Technology Data Exchange (ETDEWEB)

    Rick, W.; Benz, E.; Godichon, A.

    2001-07-01

    ABB is using 3D CFD simulations on the basis of the Navier-Stokes equations for optimizing high-performance blower design. This will also shorten development times. For an exemplary two-stage blower, numeric results are discussed for full load and part load conditions, and integral measured and calculated data are compared. Using the example of a single-stage variant, it is shown how the spiral casing could be better matched to the rotor on the basis of 3D flow calculation. [German] Fuer den Entwurf von Hochleistungsgeblaesen verwendet ABB in zunehmendem Umfang 3-D CFD-Simulationen auf der Basis der Navier-Stokes-Gleichungen um Komponenten sowie deren Abstimmung zu optimieren. Neben der Erzielung eines verbesserten Betriebsverhaltens koennen durch die Reduzierung experimenteller Untersuchungen kuerzere Entwicklungszeiten erreicht werden. Anhand eines zweiflutigen Geblaeses werden numerische Ergebnisse fuer den Voll- und Teillastbetrieb diskutiert und integrale Leistungsdaten von Rechnung und Messung verglichen. Am Beispiel einer einflutigen Variante wird gezeigt, wie auf der Basis einer 3-D Stroemungsberechnung eine verbesserte Anpassung des Spiralgehaeuses zum Laufrad erzielt werden konnte. (orig.)

  16. Temperature Histories in Ceramic-Insulated Heat-Sink Nozzle

    Science.gov (United States)

    Ciepluch, Carl C.

    1960-01-01

    Temperature histories were calculated for a composite nozzle wall by a simplified numerical integration calculation procedure. These calculations indicated that there is a unique ratio of insulation and metal heat-sink thickness that will minimize total wall thickness for a given operating condition and required running time. The optimum insulation and metal thickness will vary throughout the nozzle as a result of the variation in heat-transfer rate. The use of low chamber pressure results in a significant increase in the maximum running time of a given weight nozzle. Experimentally measured wall temperatures were lower than those calculated. This was due in part to the assumption of one-dimensional or slab heat flow in the calculation procedure.

  17. Aeroelastic stability analysis of flexible overexpanded rocket nozzle

    Science.gov (United States)

    Bekka, N.; Sellam, M.; Chpoun, A.

    2016-07-01

    The aim of this paper is to present a new aeroelastic stability model taking into account the viscous effects for a supersonic nozzle flow in overexpanded regimes. This model is inspired by the Pekkari model which was developed initially for perfect fluid flow. The new model called the "Modified Pekkari Model" (MPM) considers a more realistic wall pressure profile for the case of a free shock separation inside the supersonic nozzle using the free interaction theory of Chapman. To reach this objective, a code for structure computation coupled with aerodynamic excitation effects is developed that allows the analysis of aeroelastic stability for the overexpanded nozzles. The main results are presented in a comparative manner using existing models (Pekkari model and its extended version) and the modified Pekkari model developed in this work.

  18. The modelling of an SF6 arc in a supersonic nozzle: II. Current zero behaviour of the nozzle arc

    Science.gov (United States)

    Zhang, Q.; Liu, J.; Yan, J. D.; Fang, M. T. C.

    2016-08-01

    The present work (part II) forms the second part of an investigation into the behaviour of SF6 nozzle arc. It is concerned with the aerodynamic and electrical behaviour of a transient nozzle arc under a current ramp specified by a rate of current decay (di/dt) before current zero and a voltage ramp (dV/dt) after current zero. The five flow models used in part I [1] for cold gas flow and DC nozzle arcs have been applied to study the transient arc at three stagnation pressures (P 0) and two values of di/dt for the current ramp, representing a wide range of arcing conditions. An analysis of the physical mechanisms encompassed in each flow model is given with an emphasis on the adequacy of a particular model in describing the rapidly varying arc around current zero. The critical rate of rise of recovery voltage (RRRV) is found computationally and compared with test results of Benenson et al [2]. For transient nozzle arcs, the RRRV is proportional to the square of P 0, rather than to the square root of P 0 for DC nozzle arcs. The physical mechanisms responsible for the strong dependence of RRRV on P 0 have been investigated. The relative merits of the flow models employed are discussed.

  19. Experimental Investigation of 'Transonic Resonance' with Convergent-Divergent Nozzles

    Science.gov (United States)

    Zaman, K. B. M. Q.; Dahl, M. D.; Bencic, T. J.; Zaman, Khairul (Technical Monitor)

    2001-01-01

    Convergent-divergent nozzles, when run at pressure ratios lower than the design value, often undergo a flow resonance accompanied by the emission of acoustic tones. The phenomenon, different in characteristics from conventional 'screech' tones, has been studied experimentally. Unlike screech, the frequency increases with increasing supply pressure. There is a 'staging' behavior; 'odd harmonic' stages resonate at lower pressures while the fundamental occurs in a range of higher pressures corresponding to a fully expanded Mach number (M(sub j)) around unity. The frequency (f(sub N)) variation with M(sub j) depends on the half angle-of-divergence (theta) of the nozzle. At smaller theta, the slope of f(sub N) versus M(sub j) curve becomes steeper. The resonance involves standing waves and is driven by unsteady shock/boundary layer interaction. The distance between the foot of the shock and the nozzle exit imposes the lengthscale (L'). The fundamental corresponds to a quarterwave resonance, the next stage at a lower supply pressure corresponds to a three-quarter-wave resonance, and so on. The principal trends in the frequency variation are explained simply from the characteristic variation of the length-scale L'. Based on the data, correlation equations are provided for the prediction of f(sub N). A striking feature is that tripping of the boundary layer near the nozzle's throat tends to suppress the resonance. In a practical nozzle a tendency for the occurrence of the phenomenon is thought to be a source of 'internal noise'; thus, there is a potential for noise benefit simply by appropriate boundary layer tripping near the nozzle's throat.

  20. Numerical Optimization of converging diverging miniature cavitating nozzles

    Science.gov (United States)

    Chavan, Kanchan; Bhingole, B.; Raut, J.; Pandit, A. B.

    2015-12-01

    The work focuses on the numerical optimization of converging diverging cavitating nozzles through nozzle dimensions and wall shape. The objective is to develop design rules for the geometry of cavitating nozzles for desired end-use. Two main aspects of nozzle design which affects the cavitation have been studied i.e. end dimensions of the geometry (i.e. angle and/or curvature of the inlet, outlet and the throat and the lengths of the converging and diverging sections) and wall curvatures(concave or convex). Angle of convergence at the inlet was found to control the cavity growth whereas angle of divergence of the exit controls the collapse of cavity. CFD simulations were carried out for the straight line converging and diverging sections by varying converging and diverging angles to study its effect on the collapse pressure generated by the cavity. Optimized geometry configurations were obtained on the basis of maximum Cavitational Efficacy Ratio (CER)i.e. cavity collapse pressure generated for a given permanent pressure drop across the system. With increasing capabilities in machining and fabrication, it is possible to exploit the effect of wall curvature to create nozzles with further increase in the CER. Effect of wall curvature has been studied for the straight, concave and convex shapes. Curvature has been varied and effect of concave and convex wall curvatures vis-à-vis straight walls studied for fixed converging and diverging angles.It is concluded that concave converging-diverging nozzles with converging angle of 20° and diverging angle of 5° with the radius of curvature 0.03 m and 0.1530 m respectively gives maximum CER. Preliminary experiments using optimized geometry are indicating similar trends and are currently being carried out. Refinements of the CFD technique using two phase flow simulations are planned.

  1. EC blowers for school building ventilation. Wholesome climate and high energy efficiency; EC-Ventilatoren fuer Schullueftungskonzepte. Gesundes Klima bei hoher Energieeffizienz

    Energy Technology Data Exchange (ETDEWEB)

    Salig, Andreas [ebm-papst, Mulfingen (Germany). Verkauf Inland; Grohmann, Erwin [Grohmann Lueftungstechnik GmbH, Forchtenberg (Germany); Reiff, Ellen-Christine [Redaktionsbuero Stutensee (Germany)

    2009-07-01

    Government funds of several thousands of millions were provided in 2009 for the modernisation of school buildings. There are highly flexible commercial ventilation and air conditioning systems for this type of buildings which combine energy savings with optimum room air quality. EC blowers contribute to this. (orig.)

  2. Effect of the blade design on the dissipation and noise emission of radial blowers; Einfluss der Schaufelform auf Dissipation und Schallemission bei Radialventilatoren. Aerodynamische und akustische Qualitaetsbeurteilung

    Energy Technology Data Exchange (ETDEWEB)

    Sentek, J. [Akademia Gorniczo-Hutnicza, Cracow (Poland); Bommes, L. [Fachhochschule Duesseldorf (Germany). Inst. fuer Stroemungsmaschinen

    2000-04-01

    The flow condition caused within a radial blower by the blade design is known to have a considerable effect both on the hydraulic losses as well as on the level of the emitted noise. (orig.) [German] Der durch die Schaufelform verursachte Stroemungszustand im Inneren eines Radialventilators hat bekanntermassen einen erheblichen Einfluss sowohl auf die hydraulischen Verluste als auch auf die Staerke der Schallabstrahlung. (orig.)

  3. Criteria for selecting optimum blower drives. Integrated power electronics is gaining ground in the market; Kriterien zur Auswahl des optimalen Ventilatorantriebs. Die integrierte Leistungselektronik gewinnt Marktanteile

    Energy Technology Data Exchange (ETDEWEB)

    Albig, J. [Ziehl-Abegg AG, Kuenzelsau (Germany). Fachbereich Produktmanagement

    2008-05-15

    In the field of speed controllers, systems with power electronics are gaining ground. Thes compact, matched units simplify the installation of refrigeration systems and enable reliable and efficient operation. Design concepts vary between the various producers, and blower design and technology may be quite different. (orig.)

  4. Development of Filter-Blower Unit for use in the Advanced Nuclear Biological Chemical Protection System (ANBCPS) Helicopter/Transport-aircraft version

    NARCIS (Netherlands)

    Sabel, R.; Reffeltrath, P.A.; Jonkman, A.; Post, T.

    2006-01-01

    As a participant in the three-nation partnership for development of the ANBCP-S for use in Helicopters, Transport Aircraft and Fast Jet, the Royal Netherlands Airforce (RNLAF) picked up the challenge to design a Filter- Blower-Unit (FBU). Major Command (MajCom) of the RNLAF set priority to develop a

  5. 气动旋转式吹灰器系统的技术应用%The Actual Application of Pneumatic Soot Blower in Heat Medium Heater

    Institute of Scientific and Technical Information of China (English)

    陈江波

    2000-01-01

    The pneumatic ratchet soot blower and the structure and control principle of CKQ—Ⅱ controller as well as its application in heat medium heater are introduced.The pneumatic ratchet soot blower has got many advantages,such as high level automation control(unattended),soot blower integrated with controller,stable control process,high efficiency and easier to repair compared with conventional soot blower.This soot blower can be adopted in heater and boiler.%介绍了气动旋转式吹灰器和CKQ-Ⅱ型吹灰控制器的结构、控制原理及在热媒炉上的应用,与电动吹灰器相比,气动旋转式吹灰器具有自动化程度高、吹灰器和控制器自成系统、可实现无人职守、控制过程稳定可靠、吹灰效果理想、操作灵活、维修方便等优点。可在各种加热炉、锅炉的吹扫系统中应用。

  6. Analytical study of nozzle performance for nuclear thermal rockets

    Science.gov (United States)

    Davidian, Kenneth O.; Kacynski, Kenneth J.

    1991-01-01

    A parametric study has been conducted by the NASA-Lewis Rocket Engine Design Expert System for the convergent-divergent nozzle of the Nuclear Thermal Rocket system, which uses a nuclear reactor to heat hydrogen to high temperature and then expands it through the nozzle. It is established by the study that finite-rate chemical reactions lower performance levels from theoretical levels. Major parametric roles are played by chamber temperature and chamber pressure. A maximum performance of 930 sec is projected at 2700 K, and of 1030 at 3100 K.

  7. Injection nozzle materials for a coal-fueled diesel locomotive

    Energy Technology Data Exchange (ETDEWEB)

    Mehan, R.L.; Leonard, G.L.; Johnson, R.N.; Lavigne, R.G.

    1990-12-31

    In order to identify materials resistant to coal water mixture (CWM) erosive wear, a number of materials were evaluated using both orifice slurry and dry air erosion tests. Both erosion tests ranked materials in the same order, and the most erosion resistant material identified was sintered diamond compact. Based on operation using CWM in a single-cylinder locomotive test, superhard nozzle materials such as diamond, cubic boron nitride, and perhaps TiB{sub 2} were found to be necessary in order to obtain a reasonable operating life. An injection nozzle using sintered diamond compacts was designed and built, and has operated successfully in a CWM fired locomotive engine.

  8. Effect of nozzle geometry on the resistojet exhaust plume

    Science.gov (United States)

    Breyley, Loranell; Serafini, John S.; Hoffman, David J.; Zana, Lynette M.

    1987-01-01

    Five nozzle configurations were used to study the effect of geometry on the plume structure of a resistojet exhausting into a vacuum. Mass flux data in the forward and back flux regions were obtained with a cryogenically cooled quartz crystal microbalance. The propellant used was CO2 at 300 K and a mass flow rate of 0.2 g/s. The data reveal that the percent of mass flow contained within half angles of 10, 30, and 40 deg varied by less than 12 percent from a standard 20 deg half-angle cone nozzle.

  9. Jet Engine Nozzle Exit Configurations and Associated Systems and Methods

    Science.gov (United States)

    Mengle, Vinod G. (Inventor)

    2013-01-01

    Nozzle exit configurations and associated systems and methods are disclosed. An aircraft system in accordance with one embodiment includes a jet engine exhaust nozzle having an internal flow surface and an exit aperture, with the exit aperture having a perimeter that includes multiple projections extending in an aft direction. Aft portions of individual neighboring projections are spaced apart from each other by a gap, and a geometric feature of the multiple can change in a monotonic manner along at least a portion of the perimeter.

  10. Ice Control with Brine Spread with Nozzles on Highways

    DEFF Research Database (Denmark)

    Bolet, Lars; Fonnesbech, Jens Kristian

    2010-01-01

    . The improvements gained by the county of Funen were mainly due to the use of technologies (brine spreading with nozzles) giving a more precise spread pattern than the traditional gritting of pre-wetted salt. The spread pattern for every spreader, tested in The County of Funen, has been meassured 3 hours after...... spreading on a highway with traffic. A total of 800 spots were measured for residual salt for every spreader. The measurements and the spread pattern for brine spreading with nozzles were so precisely, that we learned: “When there is moisture, water or ice on the road, we need to take into account...

  11. Intensification of heat transfer by changing the burner nozzle

    Science.gov (United States)

    DzurÅák, Róbert; Kizek, Ján; Jablonský, Gustáv

    2016-06-01

    Thermal aggregates are using burner which burns combustible mixture with an oxidizing agent, by adjustment of the burner nozzle we can achieve better conditions of combustion to intensify heat transfer at furnace space. The aim of the present paper was using a computer program Ansys Workbench to create a computer simulation which analyzes the impact of the nozzle on the shape of a flame thereby intensifies heat transfer in rotary drum furnaces and radiation heat transfer from the flue gas into the furnace space. Article contains analysis of the geometry of the burner for achieving temperature field in a rotary drum furnace using oxy-combustion and the practical results of computer simulations

  12. Numerical study on drop formation through a micro nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Il; Son, Gi Hun [Sogang Univ., Seoul (Korea, Republic of)

    2005-02-01

    The drop ejection process from a micro nozzle is investigated by numerically solving the conservation equations for mass and momentum. The liquid-gas interface is tracked by a level set method which is extended for two-fluid flows with irregular solid boundaries. Based on the numerical results, the liquid jet breaking and droplet formation behavior is found to depend strongly on the pulse type of forcing pressure and the contact angle at the gas-liquid-solid interline. The negative pressure forcing can be used to control the formation of satelite droplets. Also, various nozzle shapes are tested to investigate their effect on droplet formation.

  13. Rocket nozzle thermal shock tests in an arc heater facility

    Science.gov (United States)

    Painter, James H.; Williamson, Ronald A.

    1986-01-01

    A rocket motor nozzle thermal structural test technique that utilizes arc heated nitrogen to simulate a motor burn was developed. The technique was used to test four heavily instrumented full-scale Star 48 rocket motor 2D carbon/carbon segments at conditions simulating the predicted thermal-structural environment. All four nozzles survived the tests without catastrophic or other structural failures. The test technique demonstrated promise as a low cost, controllable alternative to rocket motor firing. The technique includes the capability of rapid termination in the event of failure, allowing post-test analysis.

  14. Advanced nozzle characterization for hydrogen fluoride overtone chemical lasers

    Science.gov (United States)

    Duncan, William A.; Patterson, Stanley P.; Graves, Bruce R.; Sollee, Jeffrey L.; Yonehara, Gordon N.; Dering, John P.

    1992-07-01

    The parametric characterization and optimization of the hypersonic, low-temperature (HYLTE) nozzle concept for the hydrogen fluoride (HF) overtone and HF fundamental performance are reviewed. The HF fundamental space-based laser for weapons systems is considered to be more mature, nearer term potential application than the overtone. Emphasis is placed on the Task 3 advanced gain generator technology configurations (AGGTC) aimed at a thorough characterization in the fundamental regime. The experiments were based on advanced multilayer dielectric coatings on uncooled silicon substrates. It is concluded that the Task 3 AGGTC hardware functioned quite well in optimizing the performance of the HYLTE nozzle concept.

  15. Lewis Carroll, a educação e o ensino de geometria na Inglaterra vitoriana - Lewis Carroll, education and the teaching of geometry in victorian England

    Directory of Open Access Journals (Sweden)

    Rafael Montoito

    2015-04-01

    Full Text Available Parte da pesquisa motivada pela tradução para o português do livro Euclides e seus rivais modernos, publicado por Lewis Carroll em 1879, este artigo se inscreve numa série de estudos que visam a um exame hermenêutico dessa obra. São discutidos temas relacionados com a educação, a educação matemática e o ensino de geometria na Inglaterra vitoriana.Palavras-chave: Lewis Carroll, Euclides e seus rivais modernos, história da educação, educação matemática, geometria. LEWIS CARROLL, EDUCATION AND THE TEACHING OF GEOMETRY IN VICTORIAN ENGLANDAbstractResearch partly motivated by Lewis Carrroll's Euclid and his modern rivals (1879 portuguese translation, this paper presents some hermeneutical remarks taken as necessary to understand the context in which such book was produced. The paper focuses particularly on education, in general, and on the teaching of mathematics and geometry in victorian England.Key-words: Lewis Carroll, Euclid and his modern rivals, history of education, mathematics education, geometry. LEWIS CARROLL, LA EDUCACIÓN Y EL ENSINO DE GEOMETRÍA EN LA INGLATERRA VICTORIANAResumenParte de la investigación motivada por la traducción al portugués del libro Euclides y sus enemigos modernos, publicado por Lewis Carroll en 1879, este artículo se inscribe en una serie de estudios que tienen por objetivo hacer un examen hermenéutico de la obra. Son aquí discutidos temas relacionados como la educación, la educación matemática y la enseñanza de geometría en la Inglaterra victoriana.Palabras-clave: Lewis Carroll, Euclides y sus enemigos modernos, historia de la educación, educación matemática, geometría. LEWIS CARROLL, L’ÉDUCATION ET L’ENSEIGMENT DE GÉOMÉTRIE EN L’ANGLETERRE VICTORIENNERésuméFaisant partie de la recherche motivée par la traduction en portugais du livre Euclide et ses rivaux modernes, publié par Lewis Carrol en 1879 , cet article s’inscrit dans une série d’études dont le but

  16. Internal performance of two nozzles utilizing gimbal concepts for thrust vectoring

    Science.gov (United States)

    Berrier, Bobby L.; Taylor, John G.

    1990-01-01

    The internal performance of an axisymmetric convergent-divergent nozzle and a nonaxisymmetric convergent-divergent nozzle, both of which utilized a gimbal type mechanism for thrust vectoring was evaluated in the Static Test Facility of the Langley 16-Foot Transonic Tunnel. The nonaxisymmetric nozzle used the gimbal concept for yaw thrust vectoring only; pitch thrust vectoring was accomplished by simultaneous deflection of the upper and lower divergent flaps. The model geometric parameters investigated were pitch vector angle for the axisymmetric nozzle and pitch vector angle, yaw vector angle, nozzle throat aspect ratio, and nozzle expansion ratio for the nonaxisymmetric nozzle. All tests were conducted with no external flow, and nozzle pressure ratio was varied from 2.0 to approximately 12.0.

  17. Structure Optimization and Numerical Simulation of Nozzle for High Pressure Water Jetting

    Directory of Open Access Journals (Sweden)

    Shuce Zhang

    2015-01-01

    Full Text Available Three kinds of nozzles normally used in industrial production are numerically simulated, and the structure of nozzle with the best jetting performance out of the three nozzles is optimized. The R90 nozzle displays the most optimal jetting properties, including the smooth transition of the nozzle’s inner surface. Simulation results of all sample nozzles in this study show that the helix nozzle ultimately displays the best jetting performance. Jetting velocity magnitude along Y and Z coordinates is not symmetrical for the helix nozzle. Compared to simply changing the jetting angle, revolving the jet issued from the helix nozzle creates a grinding wheel on the cleaning surface, which makes not only an impact effect but also a shearing action on the cleaning object. This particular shearing action improves the cleaning process overall and forms a wider, effective cleaning range, thus obtaining a broader jet width.

  18. DURACON - Variable Emissivity Broadband Coatings for Liquid Propellant Rocket Nozzles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The need exists for a fast drying, robust, low gloss, black, high emissivity coating that can be applied easily on aircraft rocket nozzles and nozzle extensions....

  19. Computational Simulation on a Coaxial Substream Powder Feeding Laval Nozzle of Cold Spraying

    Directory of Open Access Journals (Sweden)

    Guosheng HUANG

    2014-09-01

    Full Text Available In this paper, a substream coaxial powder feeding nozzle was investigated for use in cold spraying. The relationship between nozzle structure and gas flow, the acceleration behavior of copper particles were examined by computational simulation method. Also, one of the nozzle was used to spray copper coating on steel substrate. The simulation results indicate that: the velocity of gas at the center of the nozzle is lower than that of the conventional nozzle. Powders are well restrained near the central line of the nozzle, no collision occurred between the nozzle wall and the powders. This type of nozzle with expansion 3.25 can successfully deposit copper coating on steel substrate, the copper coating has low porosity about 3.1 % – 3.8 % and high bonding strength about 23.5 MPa – 26.8 MPa. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.4244

  20. Performance characteristics of two multiaxis thrust-vectoring nozzles at Mach numbers up to 1.28

    Science.gov (United States)

    Wing, David J.; Capone, Francis J.

    1993-01-01

    The thrust-vectoring axisymmetric (VA) nozzle and a spherical convergent flap (SCF) thrust-vectoring nozzle were tested along with a baseline nonvectoring axisymmetric (NVA) nozzle in the Langley 16-Foot Transonic Tunnel at Mach numbers from 0 to 1.28 and nozzle pressure ratios from 1 to 8. Test parameters included geometric yaw vector angle and unvectored divergent flap length. No pitch vectoring was studied. Nozzle drag, thrust minus drag, yaw thrust vector angle, discharge coefficient, and static thrust performance were measured and analyzed, as well as external static pressure distributions. The NVA nozzle and the VA nozzle displayed higher static thrust performance than the SCF nozzle throughout the nozzle pressure ratio (NPR) range tested. The NVA nozzle had higher overall thrust minus drag than the other nozzles throughout the NPR and Mach number ranges tested. The SCF nozzle had the lowest jet-on nozzle drag of the three nozzles throughout the test conditions. The SCF nozzle provided yaw thrust angles that were equal to the geometric angle and constant with NPR. The VA nozzle achieved yaw thrust vector angles that were significantly higher than the geometric angle but not constant with NPR. Nozzle drag generally increased with increases in thrust vectoring for all the nozzles tested.

  1. Preliminary Tests of Blowers of Three Designs Operating in Conjunction with a Wing-Duct Cooling System for Radial Engines, Special Report

    Science.gov (United States)

    Biermann, David; Valentine, E. Floyd

    1939-01-01

    This paper is one of several dealing with methods intended to reduce the drag of present-day radial engine installations and improve the cooling at zero and low air speeds, The present paper describes model wind-tunnel tests of blowers of three designs tested in conjunction with a wing-nacelle combination. The principle of operation involved consists of drawing cooling air into ducts located in the wing root at the point of maximum slipstream velocity, passing the air through the engine baffles from rear to front, and exhausting the air through an annular slot located between the propeller and the engine with the aid of a blower mounted on the spinner. The test apparatus consisted essentially of a stub wing having a 5-foot chord and a 15-foot span, an engine nacelle of 20 inches diameter enclosing a 25-horsepower electric motor, and three blowers mounted on propeller spinners. Two of the blowers utilize centrifugal force while the other uses the lift from airfoils to force the air out radially through the exit slot. Maximum efficiencies of over 70 percent were obtained for the system as a whole. Pressures were measured over the entire flight range which were in excess of those necessary to cool present-day engines, The results indicated that blowers mounted on propeller spinners could be built sufficiently powerful and efficient to warrant their use as the only, or chief, means of forcing air through the cooling system, so that cooling would be independent of the speed of the airplane.

  2. Nozzle design in a fiber spinning process for a maximal pressure gradient

    Directory of Open Access Journals (Sweden)

    Yang Zhanping

    2013-01-01

    Full Text Available The thickness of a spinneret is always a geometrical constraint in nozzle design. The geometrical form of a nozzle has a significant effect on the subsequent spinning characteristics. This paper gives an optimal condition for maximal pressure gradient through the nozzle.

  3. Effect of spray nozzle design on fish oil-whey protein microcapsule properties.

    Science.gov (United States)

    Legako, Jerrad; Dunford, Nurhan Turgut

    2010-08-01

    Microencapsulation improves oxidative stability and shelf life of fish oil. Spray and freeze drying are widely used to produce microcapsules. Newer spray-nozzles utilize multiple fluid channels allowing for mixing of wall and core materials at the point of atomization. Sonic energy has also been employed as a means of atomization. The objective of this study was to examine the effect of nozzle type and design on fish oil encapsulation efficiency and microcapsule properties. A total of 3 nozzle types, a pressure nozzle with 1 liquid channel, a pressure nozzle with 2 liquid channels, and a sonic atomizer with 2 liquid channels were examined for their suitability to encapsulate fish oil in whey protein isolate. Physical and chemical properties of freeze dried microcapsules were compared to those of microcapsules produced by spray drying. The 2-fluid pressure and ultrasonic nozzles had the highest (91.6%) and the lowest microencapsulation efficiencies (76%), respectively. There was no significant difference in bulk density of microcapsules produced by ultrasonic and 3-fluid pressure nozzles. The ultrasonic nozzle showed a significantly narrower particle size distribution than the other nozzles. This study demonstrated that new nozzle designs that eliminate emulsion preparation prior to spray drying can be beneficial for microencapsulation applications. However, there is still a need for research to improve microencapsulation efficiency of multiple channel spray nozzles. Practical Application: Since this research evaluates new spray nozzle designs for oil microencapsulation, the information presented in this article could be an interest to fish oil producers and food industry.

  4. UMA ABORDAGEM DE CONCEITOS ELEMENTARES DE GEOMETRIA NÃO EUCLIDIANA: UMA EXPERIÊNCIA VIVENCIADA NO ENSINO DE MATEMÁTICA A PARTIR DE UMA SEQUÊNCIA DIDÁTICA

    Directory of Open Access Journals (Sweden)

    Wanderley Pivatto Brum

    2014-02-01

    Full Text Available Neste artigo apresentamos um relato de uma experiência, de caráter qualitativo, a qual teve como objetivo analisar se a utilização de diferentes atividades, por meio de uma sequência didática para o ensino de Geometria não Euclidiana, em particular, Esférica e Hiperbólica. Para isso, realizamos uma pesquisa participante com 14 estudantes da 2ª série do Ensino Médio de uma escola da rede pública de Tijucas, Santa Catarina. A pesquisa esteve sentada na Teoria da Aprendizagem Significativa de Ausubel. A pesquisa foi dividida em três momentos: no primeiro foi aplicado um pré-teste, no segundo momento ocorreu a aplicação da sequência didática, e por fim, foi aplicado um pós-teste. Os resultados evidenciam que, após a sequência grande parte dos estudantes conseguiram assimilar, diferenciar e reconciliar conceitos de Geometria Euclidiana, Esférica e Hiperbólica, por ser um tema ainda novo nos bancos escolares, houve estudantes que permaneceram com um posicionamento euclidiano frente ao problema não euclidiano.

  5. Equilibrium retention in the nozzle of oxygen hydrogen propulsion systems

    Science.gov (United States)

    Ford, D. I.

    1987-01-01

    Arguments are presented for the retention of vibrational equilibrium of species in the nozzle of the Space Shuttle Main Engine which are especially applicable to water and the hydroxyl radical. It is shown that the reaction OH + HH yields HOH + H maintains equilibrium as well. This is used to relate OH to H, the temperature, and the oxidizer-to-fuel ratio.

  6. SHINE Tritium Nozzle Design: Activity 6, Task 1 Report

    Energy Technology Data Exchange (ETDEWEB)

    Okhuysen, Brett S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pulliam, Elias Noel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-05

    In FY14, we studied the qualitative and quantitative behavior of a SHINE/PNL tritium nozzle under varying operating conditions. The result is an understanding of the nozzle’s performance in terms of important flow features that manifest themselves under different parametric profiles. In FY15, we will consider nozzle design with a focus on nozzle geometry and integration. From FY14 work, we will understand how the SHINE/PNL nozzle behaves under different operating scenarios. The first task for FY15 is to evaluate the FY14 model as a predictor of the actual flow. Considering different geometries is more time-intensive than parameter studies, therefore we recommend considering any relevant flow features that were not included in the FY14 model. In the absence of experimental data, it is particularly important to consider any sources of heat in the domain or boundary conditions that may affect the flow and incorporate these into the simulation if they are significant. Additionally, any geometric features of the beamline segment should be added to the model such as the orifice plate. The FY14 model works with hydrogen. An improvement that can be made for FY15 is to develop CFD properties for tritium and incorporate those properties into the new models.

  7. Shock unsteadiness in a thrust optimized parabolic nozzle

    Science.gov (United States)

    Verma, S. B.

    2009-07-01

    This paper discusses the nature of shock unsteadiness, in an overexpanded thrust optimized parabolic nozzle, prevalent in various flow separation modes experienced during start up {(δ P0 /δ t > 0)} and shut down {(δ P0/δ t tube. Shock unsteadiness in the separation region is seen to increase significantly just before the onset of each flow transition, even during steady nozzle operation. The intensity of this measure ( rms level) is seen to be strongly influenced by relative locations of normal and overexpansion shock, the decrease in radial size of re-circulation zone in the back-flow region, and finally, the local nozzle wall contour. During restricted shock separation, the pressure fluctuations in separation region exhibit periodic characteristics rather than the usually observed characteristics of intermittent separation. The possible physical mechanisms responsible for the generation of flow unsteadiness in various separation modes are discussed. The results are from an experimental study conducted in P6.2 cold-gas subscale test facility using a thrust optimized parabolic nozzle of area-ratio 30.

  8. Nonlinear indirect combustion noise for compact supercritical nozzle flows

    Science.gov (United States)

    Huet, M.

    2016-07-01

    In this paper, indirect combustion noise generated by the acceleration of entropy perturbations through a supercritical nozzle is investigated in the nonlinear regime and in the low-frequency limit (quasi-static hypothesis). This work completes the study of Huet and Giauque (Journal of Fluid Mechanics 733 (2013) 268-301) for nonlinear noise generation in nozzle flows without shock and particularly focuses on shocked flow regimes. It is based on the analytical model of Marble and Candel for compact nozzles (Journal of Sound and Vibration 55 (1977) 225-243), initially developed for excitations in the linear regime and rederived here for nonlinear perturbations. Full nonlinear analytical solutions are provided in the absence of shock as well as second-order analytical expressions when a shock is present in the diffuser. An analytical evaluation of the shock displacement inside the nozzle caused by the forcing is proposed and maximum possible forcings to avoid unchoke and 'over-choke' are discussed. The accuracy of the second-order model and the nonlinear contributions to the generated waves are then addressed. This model is found to be very accurate for the generated entropy wave with negligible nonlinear contributions. Nonlinearities are more visible, but still limited, for the downstream acoustic wave for large inlet Mach numbers. Analytical developments are validated thanks to comparisons with numerical simulations.

  9. Numerical modeling of a compressible multiphase flow through a nozzle

    Science.gov (United States)

    Niedzielska, Urszula; Rabinovitch, Jason; Blanquart, Guillaume

    2012-11-01

    New thermodynamic cycles developed for more efficient low temperature resource utilization can increase the net power production from geothermal resources and sensible waste heat recovery by 20-40%, compared to the traditional organic Rankine cycle. These improved systems consist of a pump, a liquid heat exchanger, a two-phase turbine, and a condenser. The two-phase turbine is used to extract energy from a high speed multiphase fluid and consists of a nozzle and an axial impulse rotor. In order to model and optimize the fluid flow through this part of the system an analysis of two-phase flow through a specially designed convergent-divergent nozzle has to be conducted. To characterize the flow behavior, a quasi-one-dimensional steady-state model of the multiphase fluid flow through a nozzle has been constructed. A numerical code capturing dense compressible multiphase flow under subsonic and supersonic conditions and the coupling between both liquid and gas phases has been developed. The output of the code delivers data vital for the performance optimization of the two-phase nozzle.

  10. High-Melt Carbon-Carbon Coating for Nozzle Extensions

    Science.gov (United States)

    Thompson, James

    2015-01-01

    Carbon-Carbon Advanced Technologies, Inc. (C-CAT), has developed a high-melt coating for use in nozzle extensions in next-generation spacecraft. The coating is composed primarily of carbon-carbon, a carbon-fiber and carbon-matrix composite material that has gained a spaceworthy reputation due to its ability to withstand ultrahigh temperatures. C-CAT's high-melt coating embeds hafnium carbide (HfC) and zirconium diboride (ZrB2) within the outer layers of a carbon-carbon structure. The coating demonstrated enhanced high-temperature durability and suffered no erosion during a test in NASA's Arc Jet Complex. (Test parameters: stagnation heat flux=198 BTD/sq ft-sec; pressure=.265 atm; temperature=3,100 F; four cycles totaling 28 minutes) In Phase I of the project, C-CAT successfully demonstrated large-scale manufacturability with a 40-inch cylinder representing the end of a nozzle extension and a 16-inch flanged cylinder representing the attach flange of a nozzle extension. These demonstrators were manufactured without spalling or delaminations. In Phase II, C-CAT worked with engine designers to develop a nozzle extension stub skirt interfaced with an Aerojet Rocketdyne RL10 engine. All objectives for Phase II were successfully met. Additional nonengine applications for the coating include thermal protection systems (TPS) for next-generation spacecraft and hypersonic aircraft.

  11. Liquid Atomization out of a Full Cone Pressure Swirl Nozzle

    CERN Document Server

    Rimbert, Nicolas

    2010-01-01

    A thorough numerical, theoretical and experimental investigation of the liquid atomization in a full cone pressure swirl nozzle is presented. The first part is devoted to the study of the inner flow. CAD and CFD software are used in order to determine the most important parameters of the flow at the exit of nozzle. An important conclusion is the existence of two flow regions: one in relatively slow motion (the boundary layer) and a second nearly in solid rotation at a very high angular rate (about 100 000 rad/s) with a thickness of about 4/5th of the nozzle section. Then, a theoretical and experimental analysis of the flow outside the nozzle is carried out. In the theoretical section, the size of the biggest drops is successfully compared to results stemming from linear instability theory. However, it is also shown that this theory cannot explain the occurrence of small drops observed in the stability domain whose size are close to the Kolmogorov and Taylor turbulent length scale. A Phase Doppler Particle Ana...

  12. Cavitation Inside High-Pressure Optically Transparent Fuel Injector Nozzles

    Science.gov (United States)

    Falgout, Z.; Linne, M.

    2015-12-01

    Nozzle-orifice flow and cavitation have an important effect on primary breakup of sprays. For this reason, a number of studies in recent years have used injectors with optically transparent nozzles so that orifice flow cavitation can be examined directly. Many of these studies use injection pressures scaled down from realistic injection pressures used in modern fuel injectors, and so the geometry must be scaled up so that the Reynolds number can be matched with the industrial applications of interest. A relatively small number of studies have shown results at or near the injection pressures used in real systems. Unfortunately, neither the specifics of the design of the optical nozzle nor the design methodology used is explained in detail in these papers. Here, a methodology demonstrating how to prevent failure of a finished design made from commonly used optically transparent materials will be explained in detail, and a description of a new design for transparent nozzles which minimizes size and cost will be shown. The design methodology combines Finite Element Analysis with relevant materials science to evaluate the potential for failure of the finished assembly. Finally, test results imaging a cavitating flow at elevated pressures are presented.

  13. Acoustic measurements of models of military style supersonic nozzle jets

    Directory of Open Access Journals (Sweden)

    Ching-Wen Kuo

    2014-02-01

    Full Text Available Modern military aircraft jet engines are designed with variable-geometry nozzles to provide optimal thrust in different operating conditions, depending on the flight envelope. However, acoustic measurements for such nozzles are scarce, due to the cost involved in making full-scale measurements and the lack of details about the exact geometries of these nozzles. Thus the present effort at Pennsylvania State University (PSU in partnership with GE Aviation and the NASA Glenn Research Center is aiming to study and characterize the acoustic field produced by supersonic jets issuing from converging-diverging military style nozzles, and to identify and test promising noise reduction techniques. An equally important objective is to develop methodology for using data obtained from small- and moderate-scale experiments to reliably predict the full-scale engine noise. The experimental results presented show reasonable agreement between small-scale and medium-scale jets, as well as between heated jets and heat-simulated ones.

  14. Vortex structures downstream a lobed nozzle/mixer

    Institute of Scientific and Technical Information of China (English)

    Hui Hu; Toshio Kobayashi

    2008-01-01

    An experimental study was conducted to investigate the evolutions of unsteady vortex structures downstream a lobed mixer/nozzle. A novel dual-plane stereoscopic PIV system was used to measure all 3-components of vorticity distributions to revealed both the large-scale streamwise vortices produced by the lobed mixer/nozzle and the Kelvin-Helmholtz vortex structures generated due to the Kelvin-Helmholtz instabilities simultaneously and quantitatively for the first time. The instantaneous and the ensemble-averaged vorticity distributions displayed quite different aspects about the evolutions of the unsteady vortex structures. While the ensemble-averaged vorticity distributions indicated the overall effect of the special geometry of the lobed nozzle/mixer on the enhanced mixing process, the instantaneous vorticity distributions elucidated many details about how the enhanced mixing process was conducted. In addition to quantitatively confirming conjectures of previous studies, further insight about the formation, evolution and interaction characteristics of the unsteady vortex structures downstream of the lobed mixer/nozzle were also uncovered quantitatively in the present study.

  15. Acoustic measurements of models of military style supersonic nozzle jets

    Institute of Scientific and Technical Information of China (English)

    Ching-Wen Kuo; Jérémy Veltin; Dennis K. McLaughlin

    2014-01-01

    Modern military aircraft jet engines are designed with variable-geometry nozzles to provide optimal thrust in different operating conditions, depending on the flight envelope. How-ever, acoustic measurements for such nozzles are scarce, due to the cost involved in making full-scale measurements and the lack of details about the exact geometries of these nozzles. Thus the present effort at Pennsylvania State University (PSU) in partnership with GE Aviation and the NASA Glenn Research Center is aiming to study and characterize the acoustic field produced by supersonic jets issuing from converging-diverging military style nozzles, and to identify and test promising noise reduction techniques. An equally important objective is to develop methodology for using data obtained from small-and moderate-scale experiments to reliably predict the full-scale engine noise. The experimental results presented show reasonable agreement between small-scale and medium-scale jets, as well as between heated jets and heat-simulated ones.

  16. Radical recombination in a hydrocarbon-fueled scramjet nozzle

    Directory of Open Access Journals (Sweden)

    Zhang Xiaoyuan

    2014-12-01

    Full Text Available To reveal the radical recombination process in the scramjet nozzle flow and study the effects of various factors of the recombination, weighted essentially non-oscillatory (WENO schemes are applied to solve the decoupled two-dimensional Euler equations with chemical reactions to simulate the hydrocarbon-fueled scramjet nozzle flow. The accuracy of the numerical method is verified with the measurements obtained by a shock tunnel experiment. The overall model length is nearly 0.5 m, with inlet static temperatures ranging from 2000 K to 3000 K, inlet static pressures ranging from 75 kPa to 175 kPa, and inlet Mach numbers of 2.0 ± 0.4 are involved. The fraction Damkohler number is defined as functions of static temperature and pressure to analyze the radical recombination progresses. Preliminary results indicate that the energy releasing process depends on different chemical reaction processes and species group contributions. In hydrocarbon-fueled scramjet nozzle flow, reactions with H have the greatest contribution during the chemical equilibrium shift. The contrast and analysis of the simulation results show that the radical recombination processes influenced by inflow conditions and nozzle scales are consistent with Damkohler numbers and potential dissociation energy release. The increase of inlet static temperature improves both of them, thus making the chemical non-equilibrium effects on the nozzle performance more significant. While the increase of inlet static pressure improves the former one and reduces the latter, it exerts little influence on the chemical non-equilibrium effects.

  17. Vortex flow and cavitation in diesel injector nozzles

    Science.gov (United States)

    Andriotis, A.; Gavaises, M.; Arcoumanis, C.

    Flow visualization as well as three-dimensional cavitating flow simulations have been employed for characterizing the formation of cavitation inside transparent replicas of fuel injector valves used in low-speed two-stroke diesel engines. The designs tested have incorporated five-hole nozzles with cylindrical as well as tapered holes operating at different fixed needle lift positions. High-speed images have revealed the formation of an unsteady vapour structure upstream of the injection holes inside the nozzle volume, which is referred to as . Computation of the flow distribution and combination with three-dimensional reconstruction of the location of the strings inside the nozzle volume has revealed that strings are found at the core of recirculation zones; they originate either from pre-existing cavitation sites forming at sharp corners inside the nozzle where the pressure falls below the vapour pressure of the flowing liquid, or even from suction of outside air downstream of the hole exit. Processing of the acquired images has allowed estimation of the mean location and probability of appearance of the cavitating strings in the three-dimensional space as a function of needle lift, cavitation and Reynolds number. The frequency of appearance of the strings has been correlated with the Strouhal number of the vortices developing inside the sac volume; the latter has been found to be a function of needle lift and hole shape. The presence of strings has significantly affected the flow conditions at the nozzle exit, influencing the injected spray. The cavitation structures formed inside the injection holes are significantly altered by the presence of cavitation strings and are jointly responsible for up to 10% variation in the instantaneous fuel injection quantity. Extrapolation using model predictions for real-size injectors operating at realistic injection pressures indicates that cavitation strings are expected to appear within the time scales of typical injection

  18. Que geometria ensinar? uma breve história da redefinição do conhecimento elementar matemático para crianças Which geometry should we teach? a brief history of the redefinition of elementary mathematics knowledge for children

    Directory of Open Access Journals (Sweden)

    Wagner Rodrigues Valente

    2013-04-01

    Full Text Available O artigo aborda a geometria para crianças, seu ensino para alunos das primeiras séries escolares. Leva em conta, inicialmente, a trajetória da Geometria para o nível elementar, desde, praticamente, a Independência do Brasil. Nessa análise, evidencia a permanência de conteúdos da geometria euclidiana até quase meados do século XX. Em seguida, analisa as propostas de alteração do ensino de Geometria elaboradas na década de 1960. Com isso, procura mostrar as intenções de modificar os conteúdos desse ramo matemático, em busca da redefinição de um novo elementar: um novo conhecimento elementar de geometria, vindo de processos de apropriação das contribuições trazidas pelos estudos da Psicologia cognitiva.The article discusses geometry for children and its teaching for students from early grades. It takes into account, firstly, the geometry journey at the elementary level since practically the Independence of Brazil. This analysis highlights the presence of Euclidean geometry contents up to the mid-twentieth century. It then analyzes the proposed amendment to the teaching of geometry developed in the 1960s. Thus, this article attempts to show the intentions to modify the contents of this branch of mathematics in search of a redefinition of the 'new elementary': a new elementary knowledge of geometry, coming from the appropriation processes of the contributions made by studies of cognitive psychology.

  19. Dewetting Process of Blast Furnace Blower%高炉鼓风机前脱湿技术

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    Blast furnace dewetting blast is an important measure for energy conservation of blast furnace and it plays an important role in stabilizing production of blast furnace. The dewetting process and features of blast blower are described. The significance to popularize the process in steel enterprises is introduced briefly.%  高炉脱湿鼓风是高炉节能的重要措施,并对高炉的稳定生产具有重要作用。对高炉鼓风机前脱湿的工艺和特点进行说明,并简述其在钢铁企业推广的意义。

  20. Development of the Blower Efficiency Measuring Instrument%风机效率测试仪的研制

    Institute of Scientific and Technical Information of China (English)

    任仁良

    2001-01-01

    This paper describes the basic principles of blower efficiency measuring instrument which is developed by adopting microprocessor technology.Mathematic models of measurement and calculation as well as realization methods are discussed,Software calibration method is used to increase measuring accuracy and reliability.Actual application shows high measuring accuracy and easy operation of the instrument.%本文论述了利用单片机技术研制成功的风机效率测试仪的基本原理、测量和运算的数学模型及其实现方法。采用软件校正的办法,提高了测量精度和可靠性。实际使用表明,该测试仪测量精度高,操作简单。

  1. Failure Analysis of Blower Wheel%鼓风机转子叶轮失效分析

    Institute of Scientific and Technical Information of China (English)

    张峥; 苏梅; 钟群鹏

    2001-01-01

    The failure of blower wheel is caused by corrosion fatigue with the analysis of material, macro and micro fracture appearance, and composition of corrosion material. The crack initiated from the corrosion pits. The analysis result provides the technological support to prevent the same accident.%通过材质、断口宏微观和腐蚀产物成分分析,确定鼓风机转子叶轮失效模式为腐蚀疲劳,鼓风机转子叶轮上裂纹起源于腐蚀坑。分析结果为防止类似事故的再次发生提供了技术依据。

  2. Forecasting of wide band noise in axial blowers. Part 1; Prognoseverfahren fuer den Breitbandlaerm bei Axialventilatoren - Teil 1

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M.; Carolus, T. [Universitaet Siegen (Germany). Institut fuer Fluid- und Thermodynamik

    2003-04-01

    Next to the aerodynamic data, acoustic emissions of blowers are getting increasing attention. So far, estimates have been very simple, but a number of semi-empirical models have also been published which require more detailed parameters, e.g. the velocity field around the blades, boundary layer parameter, etc. These models provide more accurate predictions than the simpler methods. [German] Neben den aerodynamischen Daten gewinnt die Schallleistung von Ventilatoren in zunehmendem Masse an Bedeutung. In der industriellen Praxis wird das Ventilatorgeraeusch bislang mit sehr einfachen Verfahren abgeschaetzt, die nur grundlegende Maschinengroessen beruecksichtigen. In der Literatur findet man allerdings eine Vielzahl semi-empirischer Modelle fuer die Schallleistungsberechnung von Ventilatoren, die detailliertere Eingangsparameter wie das Geschwindigkeitsfeld um die Schaufeln, Grenzschichtparameter usw. erfordern. Diese Modelle versprechen eine bessere Schallprognose als die einfachen Verfahren. (orig.)

  3. Development of Roots Blower with High Temperature%高温罗茨鼓风机的研发

    Institute of Scientific and Technical Information of China (English)

    张海芹

    2013-01-01

      介绍了一种进气温度高达200℃的高温用途罗茨鼓风机,并着重阐述了机组的隔热结构设计、高温气体密封、降温设计和选用的隔热材料。通过对机组进行200℃高温性能试验,验证了机组性能满足工况要求。%This paper introduced a type of roots blower with inlet temperature up to 200℃ for high temperature application. And this paper focused on heat insulation design, high-temperature gas seal, cooling design and selection of heat insulation material of the unit. The unit performance meeting the operating requirement was verified based on the 200℃ high temperature performance test for the unit.

  4. Effectiveness of mist-blower applications of malathion and permethrin to foliage as barrier sprays for salt marsh mosquitoes.

    Science.gov (United States)

    Anderson, A L; Apperson, C S; Knake, R

    1991-03-01

    Permethrin and malathion were applied as salt marsh mosquito barrier sprays by mist-blower to the shrub border of a park. At one and 24 h after treatment, mosquito landing counts in both insecticide treated areas declined by 80-90% relative to counts in an untreated control area. After 48 h, in the malathion-treated area, mosquito activity returned to levels observed in the control area. From 2 to 8 days post-treatment, mosquito landing counts in the permethrin-treated area remained depressed and significantly (P less than 0.01) different from the malathion-treated and control areas. On days 9 and 10 post-treatment, mosquito landing rates returned to high levels in the insecticide-treated and control areas.

  5. Turbine combustor with fuel nozzles having inner and outer fuel circuits

    Science.gov (United States)

    Uhm, Jong Ho; Johnson, Thomas Edward; Kim, Kwanwoo

    2013-12-24

    A combustor cap assembly for a turbine engine includes a combustor cap and a plurality of fuel nozzles mounted on the combustor cap. One or more of the fuel nozzles would include two separate fuel circuits which are individually controllable. The combustor cap assembly would be controlled so that individual fuel circuits of the fuel nozzles are operated or deliberately shut off to provide for physical separation between the flow of fuel delivered by adjacent fuel nozzles and/or so that adjacent fuel nozzles operate at different pressure differentials. Operating a combustor cap assembly in this fashion helps to reduce or eliminate the generation of undesirable and potentially harmful noise.

  6. System and method having multi-tube fuel nozzle with differential flow

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Michael John; Johnson, Thomas Edward; Berry, Jonathan Dwight; York, William David

    2017-01-03

    A system includes a multi-tube fuel nozzle with a fuel nozzle body and a plurality of tubes. The fuel nozzle body includes a nozzle wall surrounding a chamber. The plurality of tubes extend through the chamber, wherein each tube of the plurality of tubes includes an air intake portion, a fuel intake portion, and an air-fuel mixture outlet portion. The multi-tube fuel nozzle also includes a differential configuration of the air intake portions among the plurality of tubes.

  7. Parametric Study of Afterbody/nozzle Drag on Twin Two-dimensional Convergent-divergent Nozzles at Mach Numbers from 0.60 to 1.20

    Science.gov (United States)

    Pendergraft, Odis C., Jr.; Burley, James R., II; Bare, E. Ann

    1986-01-01

    An investigation has been conducted in the Langley 16-Foot Transonic Tunnel to determine the effects of upper and lower external nozzle flap geometry on the external afterbody/nozzle drag of nonaxisymmetric two-dimensional convergent-divergent exhaust nozzles having parallel external sidewalls installed on a generic twin-engine, fighter-aircraft model. Tests were conducted over a Mach number range from 0.60 to 1.20 and over an angle-of-attack range from -5 to 9 deg. Nozzle pressure ratio was varied from jet off (1.0) to approximately 10.0, depending on Mach number.

  8. The proton therapy nozzles at Samsung Medical Center: A Monte Carlo simulation study using TOPAS

    Science.gov (United States)

    Chung, Kwangzoo; Kim, Jinsung; Kim, Dae-Hyun; Ahn, Sunghwan; Han, Youngyih

    2015-07-01

    To expedite the commissioning process of the proton therapy system at Samsung Medical Center (SMC), we have developed a Monte Carlo simulation model of the proton therapy nozzles by using TOol for PArticle Simulation (TOPAS). At SMC proton therapy center, we have two gantry rooms with different types of nozzles: a multi-purpose nozzle and a dedicated scanning nozzle. Each nozzle has been modeled in detail following the geometry information provided by the manufacturer, Sumitomo Heavy Industries, Ltd. For this purpose, the novel features of TOPAS, such as the time feature or the ridge filter class, have been used, and the appropriate physics models for proton nozzle simulation have been defined. Dosimetric properties, like percent depth dose curve, spreadout Bragg peak (SOBP), and beam spot size, have been simulated and verified against measured beam data. Beyond the Monte Carlo nozzle modeling, we have developed an interface between TOPAS and the treatment planning system (TPS), RayStation. An exported radiotherapy (RT) plan from the TPS is interpreted by using an interface and is then translated into the TOPAS input text. The developed Monte Carlo nozzle model can be used to estimate the non-beam performance, such as the neutron background, of the nozzles. Furthermore, the nozzle model can be used to study the mechanical optimization of the design of the nozzle.

  9. Effects of Nozzle Geometry and Intermittent Injection of Aerodynamic Tab on Supersonic Jet Noise

    Science.gov (United States)

    Araki, Mikiya; Sano, Takayuki; Fukuda, Masayuki; Kojima, Takayuki; Taguchi, Hideyuki; Shiga, Seiichi; Obokata, Tomio

    Effects of the nozzle geometry and intermittent injection of aerodynamic tabs on exhaust noise from a rectangular plug nozzle were investigated experimentally. In JAXA (Japan Aerospace Exploration Agency), a pre-cooled turbojet engine for an HST (Hypersonic transport) is planned. A 1/100-scaled model of the rectangular plug nozzle is manufactured, and the noise reduction performance of aerodynamic tabs, which is small air jet injection from the nozzle wall, was investigated. Compressed air is injected through the rectangular plug nozzle into the atmosphere at the nozzle pressure ratio of 2.7, which corresponds to the take-off condition of the vehicle. Aerodynamic tabs were installed at the sidewall ends, and 4 kinds of round nozzles and 2 kinds of wedge nozzles were applied. Using a high-frequency solenoid valve, intermittent gas injection is also applied. It is shown that, by use of wedge nozzles, the aerodynamic tab mass flow rate, necessary to gain 2.3dB reduction in OASPL (Overall sound pressure level), decreases by 29% when compared with round nozzles. It is also shown that, by use of intermittent injection, the aerodynamic tab mass flow rate, necessary to gain 2.3dB reduction in OASPL, decreases by about 40% when compared with steady injection. By combination of wedge nozzles and intermittent injection, the aerodynamic tab mass flow rate significantly decreases by 57% when compared with the conventional strategy.

  10. Static investigation of two STOL nozzle concepts with pitch thrust-vectoring capability

    Science.gov (United States)

    Mason, M. L.; Burley, J. R., II

    1986-01-01

    A static investigation of the internal performance of two short take-off and landing (STOL) nozzle concepts with pitch thrust-vectoring capability has been conducted. An axisymmetric nozzle concept and a nonaxisymmetric nozzle concept were tested at dry and afterburning power settings. The axisymmetric concept consisted of a circular approach duct with a convergent-divergent nozzle. Pitch thrust vectoring was accomplished by vectoring the approach duct without changing the nozzle geometry. The nonaxisymmetric concept consisted of a two dimensional convergent-divergent nozzle. Pitch thrust vectoring was implemented by blocking the nozzle exit and deflecting a door in the lower nozzle flap. The test nozzle pressure ratio was varied up to 10.0, depending on model geometry. Results indicate that both pitch vectoring concepts produced resultant pitch vector angles which were nearly equal to the geometric pitch deflection angles. The axisymmetric nozzle concept had only small thrust losses at the largest pitch deflection angle of 70 deg., but the two-dimensional convergent-divergent nozzle concept had large performance losses at both of the two pitch deflection angles tested, 60 deg. and 70 deg.

  11. 加热炉风机噪声特征及控制方法%Characteristics of noise from blower of reheating furnace and its control method

    Institute of Scientific and Technical Information of China (English)

    张天久; 丁岳明

    2011-01-01

    The noise coming from running blowers of the reheating furnace installed in the technical revamp of a specific mill severely contaminates the environments and hurts the health of the worker and staff.In light of the character of the noise from the blower of the reheating furnace a series counter measures have been taken such as installing a silencers at the inlet of the blower,improving the flexible link of the tuyeres,strengthening the stiffness of the blade of rotors,making proper balance between the dynamic and static status of the blade of rotors and checking and examining their vibration,controlling the value of vibration speed within the range of less than 5 mm/s,selecting proper sound insulation door and windows and wrapping the shell of the blower and network of tubes with selected sound absorb materials,well adjusting the wind blow rate,controlling the angle of the wind door and avoiding the abnormal noise from the ventilation system and mutation.By adoption of the above mentioned noise reduction measures the noise from the reheating furnace blowers has been lowered to about 78 db(A) from original 84 db(A),an average reduction of noise about 6 db(A),therefore the environmental conditions around the blower chamber have been greatly improved.%某厂在技术改造中所安装的加热炉风机运行时产生的噪声严重污染环境并有损职工健康。针对加热炉风机噪声特征,在风机进口处设计安装了阻性复合消声器,改进风口的软连接,增强转子叶轮刚度,做好转子叶轮的动静平衡及振动检测,把振动速度值控制在5 mm/s以下;选用隔声门和隔声窗并采用吸声材料包扎风机外壳和管网,调整风量,控制风门角度,避开通风系统异常噪声及突变。实施一系列降噪措施后使加热炉风机的噪声从84 dB(A)左右降低到78 dB(A)左右,平均降低了6 dB(A),使风机室周边环境得到了改善。

  12. Investigation of Thrust and Drag Characteristics of a Plug-type Exhaust Nozzle

    Science.gov (United States)

    Hearth, Donald P; Gorton, Gerald C

    1954-01-01

    An investigation was conducted in the 8- by 6-foot supersonic wind tunnel on the external and internal characteristics of a plug-type exhaust nozzle. Two positions of the center plug, one simulating a convergent nozzle and the other a convergent-divergent nozzle, were investigated. Data were obtained at free-stream Mach numbers of 0.1, 0.6, 1.6, and 2.0 over a pressure-ratio range of 1 to 20 and angles of attack of zero and 8 degrees. Results of this investigation indicated that the plug nozzle had thrust-minus-drag performance over the entire pressure-ratio range comparable with equivalent conventional nozzles. The effect of the exhaust jet on the external aerodynamics was similar to results observed for conventional nozzles. In addition, the thrust characteristics were generally insensitive to external flow and good agreement was noted with data obtained on comparable plug nozzles in quiescent air.

  13. Wall Pressure Measurements in a Convergent-Divergent Nozzle with Varying Inlet Asymmetry

    Science.gov (United States)

    Senthilkumar, C.; Elangovan, S.; Rathakrishnan, E.

    2016-06-01

    In this paper, flow separation of a convergent-divergent (C-D) nozzle is placed downstream of a supersonic flow delivered from Mach 2.0 nozzle is investigated. Static pressure measurements are conducted using pressure taps. The flow characteristics of straight and slanted entry C-D nozzle are investigated for various NPR of Mach 2.0 nozzle. The effect of asymmetry at inlet by providing 15°, 30°, 45° and 57° cut is analyzed. Particular attention is given to the location of the shock within the divergent section of the test nozzle. This location is examined as a function both NPR of Mach 2.0 nozzle and test nozzle inlet angle. Some of the measurements are favorably compared to previously developed theory. A Mach number ratio of 0.81 across the flow separation region was obtained.

  14. Modeling parameter influences on MHD swirl combustion nozzle design

    Science.gov (United States)

    Lilley, D. G.; Gupta, A. K.; Busnaina, A. A.

    1982-01-01

    Attention is given to a research project which has the goal to develop a two-stage slagging gasifier-combustor in the form of a high-intensity combustor, taking into account a suitable aerodynamic design of the second stage nozzle which will prevent the separation of the boundary layer as the flow turns from axial to radial direction. The specific objectives of the present investigation are to test the effect of various second-stage nozzle geometries, flow rates, swirl number, and distribution in the first and second stages upon the corresponding flowfield in the second stage. Special emphasis is given to the avoidance of boundary layer separation as the flow turns from axial to radial direction into the MHD disk generator.

  15. 3D Reacting Flow Analysis of LANTR Nozzles

    Science.gov (United States)

    Stewart, Mark E. M.; Krivanek, Thomas M.; Hemminger, Joseph A.; Bulman, M. J.

    2006-01-01

    This paper presents performance predictions for LANTR nozzles and the system implications for their use in a manned Mars mission. The LANTR concept is rocket thrust augmentation by injecting Oxygen into the nozzle to combust the Hydrogen exhaust of a Nuclear Thermal Rocket. The performance predictions are based on three-dimensional reacting flow simulations using VULCAN. These simulations explore a range of O2/H2 mixture ratios, injector configurations, and concepts. These performance predictions are used for a trade analysis within a system study for a manned Mars mission. Results indicate that the greatest benefit of LANTR will occur with In-Situ Resource Utilization (ISRU). However, Hydrogen propellant volume reductions may allow greater margins for fitting tanks within the launch vehicle where packaging issues occur.

  16. Development of Submerged Entry Nozzles that Resist Clogging

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Jeffrey D. Smith; Kent D. Peasle

    2002-10-14

    Accretion formation and the associated clogging of SENs is a major problem for the steel industry leading to decreased strand speed, premature changing of SENs or strand termination and the associated reductions in productivity, consistency, and steel quality. A program to evaluate potentially clog resistance materials was initiated at the University of Missouri-Rolla. The main objective of the research effort was to identify combinations of steelmaking and refractory practices that would yield improved accretion resistance for tundish nozzles and submerged entry nozzles. A number of tasks were identified during the initial kick-off meeting and each was completed with two exceptions, the thermal shock validation and the industrial trials. Not completing these two tasks related to not having access to industrial scale production facilities. Though much of the results and information generated in the project is of proprietary nature.

  17. Cooling nozzles characteristics for numerical models of continuous casting

    Directory of Open Access Journals (Sweden)

    R. Pyszko

    2013-10-01

    Full Text Available Modelling the temperature field of a continuously cast strand is an important tool for the process diagnostics. The main preconditions for numerical simulation of the temperature field of the solidifying strand are correct boundary conditions, especially the surface condition in the secondary zone of the caster. The paper deals with techniques of determining the surface condition under cooling nozzles as well as their approximation and implementation into the model algorithm. Techniques used for laboratory measurements of both cold and hot spraying characteristics of water or water-air cooling nozzles are described. The relationship between the cold and hot characteristics was found. Implementation of such a dependence into the model algorithm reduces the duration and cost of laboratory measurements.

  18. Reaction thrust of water jet for conical nozzles

    Institute of Scientific and Technical Information of China (English)

    HUANG Guo-qin; YANG You-sheng; LI Xiao-hui; ZHU Yu-quan

    2009-01-01

    Clear knowledge on the reaction thrust of water jet is valuable for better design of water jet propulsion system.In this paper,theoretical,numerical and experimental studies were carried out to investigate the effects of the nozzle geometry as well as the inlet conditions on the reaction thrust of water jet.Comparison analyses reveal that the reaction thrust has a direct proportional relationship with the product of the inlet pressure,the square of flow rate and two-thirds power exponent of the input power.The results also indicate that the diameter of the cylinder column for the conical nozzle has great influence on the reaction thrust characteristics.In addition,the best values of the half cone angle and the cylinder column length exist to make the reaction thrust reach its maximum under the same inlet conditions.

  19. Low NOx nozzle tip for a pulverized solid fuel furnace

    Science.gov (United States)

    Donais, Richard E; Hellewell, Todd D; Lewis, Robert D; Richards, Galen H; Towle, David P

    2014-04-22

    A nozzle tip [100] for a pulverized solid fuel pipe nozzle [200] of a pulverized solid fuel-fired furnace includes: a primary air shroud [120] having an inlet [102] and an outlet [104], wherein the inlet [102] receives a fuel flow [230]; and a flow splitter [180] disposed within the primary air shroud [120], wherein the flow splitter disperses particles in the fuel flow [230] to the outlet [104] to provide a fuel flow jet which reduces NOx in the pulverized solid fuel-fired furnace. In alternative embodiments, the flow splitter [180] may be wedge shaped and extend partially or entirely across the outlet [104]. In another alternative embodiment, flow splitter [180] may be moved forward toward the inlet [102] to create a recessed design.

  20. German blowers for the world. Hidden champion: Ziehl-Abegg; Deutsche Ventilatoren fuer die ganze Welt. 'Hidden Champion: Ziehl-Abegg

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2002-05-01

    In the past 5 years, Ziehl-Abegg increased their exports to 60 percent, especially in the field of ventilation and blowers. [German] In den vergangenen 5 Jahren hat sich der Exportanteil bei Ziehl-Abegg auf 60 Prozent erhoeht. Hauptanteil daran hat die Lueftungstechnik, wozu auch Ventilatoren fuer kaelte- und klimatechnische Anwendungen zaehlen. Und obwohl das Familienunternehmen heute im Weltmarkt zur Spitze zaehlt, wurde bislang kein grosses Aufheben darum gemacht. (orig.)

  1. Novel geometry for rotor and casing. Radial blowers of the drum rotor type; Neuartige Laufrad- und Gehaeusegeometrie. Radialventilatoren in Trommellaeufer-Bauweise

    Energy Technology Data Exchange (ETDEWEB)

    Riedel, Hans Jochen [YOCIEL Klimatechnik, Leipzig (Germany)

    2008-11-15

    In blowers with drum rotors, i.e. with forward-curved blades, much energy is consumed for raising the internal air flow rate, and they are not efficient in converting this high velocity into static pressure. This was the starting point for new research whose results are presented here. Modifications of the rotor and casing geometry reduced the internal air flow rate and resulted in higher static pressure gradients, lower energy consumption, and also lower noise. (orig.)

  2. Detailed noise propagation of blower-ventilated liquefiers/recirculation coolers installed outside; Detaillierte Schallausbreitung von ventilatorbeluefteten Verfluessigern / Rueckkuehlern bei Aussenaufstellung

    Energy Technology Data Exchange (ETDEWEB)

    Roth, P. [Guentner AG und Co. KG, Fuerstenfeldbruck (Germany). Abt. Versuch

    2006-07-01

    Experimentally identified and parametrized noise pressure level distributions (Goldemund (1)) of outdoor heat exchangers with blowers provide a new and detailed basis for nose emissions planning. Inhomogeneous noise emission characteristics were not known before; they often caused noise emissions exceeding limiting values even though the noise calculations for the plants had been correct. Using selected examples, it is shown how spatially resolved noise pressure level distributions can help optimize both the type and number of units and their site and positioning. (orig.)

  3. EC technology for blower drives. Maximum efficiency across the whole speed range; EC-Technik fuer Ventilator- und Geblaeseantriebe. Hoechste Wirkungsgrade im gesamten Drehzahlbereich

    Energy Technology Data Exchange (ETDEWEB)

    Sauer, T. [ebm-papst Mulfingen GmbH und Co. KG, Mulfingen (Germany)

    2006-03-15

    Blowers are often powered by rotary-current asynchronous motors with short-circuit rotors, which are robust, simple and reliable. Today, specifications have become more demanding. For example, economic efficiency and low noise - combined with speed control which again should be as simple as possible - are now required. Asynchronous motors are hardly capable of meeting these requirements, so they are being replaced in many applications by electronically commuted permanent magnet motors, so-called EC drives. (orig.)

  4. Thermal analysis of the MC-1 chamber/nozzle

    Science.gov (United States)

    Davis, Darrell

    2001-02-01

    This paper will describe the thermal analysis techniques used to predict temperatures in the film-cooled ablative rocket nozzle used on the MC-1 60K rocket engine. A model was developed that predicts char and pyrolysis depths, liner thermal gradients, and temperatures of the bondline between the overwrap and liner. Correlation of the model was accomplished by thermal analog tests performed at Southern Research, and specially instrumented hot fire tests at the Marshall Space Flight Center. Infrared thermography was instrumental in defining nozzle hot wall surface temperatures. In-depth and outboard thermocouple data was used to correlate the kinetic decomposition routine used to predict char and pyrolysis depths. These depths were anchored with measured char and pyrolysis depths from cross-sectioned hot-fire nozzles. For the X-34 flight analysis, the model includes the ablative Thermal Protection System (TPS) material that protects the overwrap from the recirculating plume. Results from model correlation, hot-fire testing, and flight predictions will be discussed .

  5. Measuring Spray Droplet Size from Agricultural Nozzles Using Laser Diffraction.

    Science.gov (United States)

    Fritz, Bradley K; Hoffmann, W Clint

    2016-09-16

    When making an application of any crop protection material such as an herbicide or pesticide, the applicator uses a variety of skills and information to make an application so that the material reaches the target site (i.e., plant). Information critical in this process is the droplet size that a particular spray nozzle, spray pressure, and spray solution combination generates, as droplet size greatly influences product efficacy and how the spray moves through the environment. Researchers and product manufacturers commonly use laser diffraction equipment to measure the spray droplet size in laboratory wind tunnels. The work presented here describes methods used in making spray droplet size measurements with laser diffraction equipment for both ground and aerial application scenarios that can be used to ensure inter- and intra-laboratory precision while minimizing sampling bias associated with laser diffraction systems. Maintaining critical measurement distances and concurrent airflow throughout the testing process is key to this precision. Real time data quality analysis is also critical to preventing excess variation in the data or extraneous inclusion of erroneous data. Some limitations of this method include atypical spray nozzles, spray solutions or application conditions that result in spray streams that do not fully atomize within the measurement distances discussed. Successful adaption of this method can provide a highly efficient method for evaluation of the performance of agrochemical spray application nozzles under a variety of operational settings. Also discussed are potential experimental design considerations that can be included to enhance functionality of the data collected.

  6. Chemical processes in the turbine and exhaust nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Lukachko, S.P.; Waitz, I.A. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Aero-Environmental Lab.; Miake-Lye, R.C.; Brown, R.C.; Anderson, M.R. [Aerodyne Research, Inc., Billerica, MA (United States); Dawes, W.N. [University Engineering Dept., Cambridge (United Kingdom). Whittle Lab.

    1997-12-31

    The objective is to establish an understanding of primary pollutant, trace species, and aerosol chemical evolution as engine exhaust travels through the nonuniform, unsteady flow fields of the turbine and exhaust nozzle. An understanding of such processes is necessary to provide accurate inputs for plume-wake modeling efforts and is therefore a critical element in an assessment of the atmospheric effects of both current and future aircraft. To perform these studies, a numerical tool was developed combining the calculation of chemical kinetics and one-, two-, or three-dimensional (1-D, 2-D, 3-D) Reynolds-averaged flow equations. Using a chemistry model that includes HO{sub x}, NO{sub y}, SO{sub x}, and CO{sub x} reactions, several 1-D parametric analyses were conducted for the entire turbine and exhaust nozzle flow path of a typical advanced subsonic engine to understand the effects of various flow and chemistry uncertainties on a baseline 1-D result. These calculations were also used to determine parametric criteria for judging 1-D, 2-D, and 3-D modeling requirements as well as to provide information about chemical speciation at the nozzle exit plane. (author) 9 refs.

  7. Exhaust Nozzle Materials Development for the High Speed Civil Transport

    Science.gov (United States)

    Grady, J. E.

    1999-01-01

    The United States has embarked on a national effort to develop the technology necessary to produce a Mach 2.4 High Speed Civil Transport (HSCT) for entry into service by the year 2005. The viability of this aircraft is contingent upon its meeting both economic and environmental requirements. Two engine components have been identified as critical to the environmental acceptability of the HSCT. These include a combustor with significantly lower emissions than are feasible with current technology, and a lightweight exhaust nozzle that meets community noise standards. The Enabling Propulsion Materials (EPM) program will develop the advanced structural materials, materials fabrication processes, structural analysis and life prediction tools for the HSCT combustor and low noise exhaust nozzle. This is being accomplished through the coordinated efforts of the NASA Lewis Research Center, General Electric Aircraft Engines and Pratt & Whitney. The mission of the EPM Exhaust Nozzle Team is to develop and demonstrate this technology by the year 1999 to enable its timely incorporation into HSCT propulsion systems.

  8. Piezoelectric diffuser/nozzle micropump with double pump chambers

    Institute of Scientific and Technical Information of China (English)

    Wei WANG; Ying ZHANG; Li TIAN; Xiaojie CHEN; Xiaowei LIU

    2008-01-01

    To eliminate check valve fatigue and valve clogging, diffuser/nozzle elements are used for flow rec-tification in a valveless diffuser/nozzle micropump instead of valves. However, the application of this type of micro-pump is restricted because of its pulsating or periodic flow and low pump flux. In this paper, a diffuser/nozzle Si/ Glass micropump with two pump chambers by IC and MEMS technology is designed. The fabrication process requires only one mask and one etch step, so that the fabrication has the advantages of low cost, short proces-sing period, and facilitation of miniaturization. The pump is equipped with a glass cover board so as to conveniently observe the flow status. Pump-chambers and diffuser ele-ments are fabricated by the anisotropic KOH-etch tech-nique on the silicone substrate, and the convex corner is designed to compensate for an anisotropic etch. The driv-ing force of the micropump is produced by the PZT piezo-electric actuator, The pump performance with both actuators actuated in anti- or same-phase mode is also researched. The result indicates that the micropump achieves great performance with the actuators working at anti-phase. This may be because the liquid flows stead-ily, pulse phenomenon is very weak, and the optimal working frequency, pump back pressure, and flow rate are both double that of the pump driven in same-phase.

  9. Thermal Barriers Developed for Solid Rocket Motor Nozzle Joints

    Science.gov (United States)

    Steinetz, Bruce M.; Dunlap, Patrick H., Jr.

    2000-01-01

    Space shuttle solid rocket motor case assembly joints are sealed with conventional O-ring seals that are shielded from 5500 F combustion gases by thick layers of insulation and by special joint-fill compounds that fill assembly splitlines in the insulation. On a number of occasions, NASA has observed hot gas penetration through defects in the joint-fill compound of several of the rocket nozzle assembly joints. In the current nozzle-to-case joint, NASA has observed penetration of hot combustion gases through the joint-fill compound to the inboard wiper O-ring in one out of seven motors. Although this condition does not threaten motor safety, evidence of hot gas penetration to the wiper O-ring results in extensive reviews before resuming flight. The solid rocket motor manufacturer (Thiokol) approached the NASA Glenn Research Center at Lewis Field about the possibility of applying Glenn's braided fiber preform seal as a thermal barrier to protect the O-ring seals. Glenn and Thiokol are working to improve the nozzle-to-case joint design by implementing a more reliable J-leg design and by using a braided carbon fiber thermal barrier that would resist any hot gases that the J-leg does not block.

  10. Development of Thermal Barriers For Solid Rocket Motor Nozzle Joints

    Science.gov (United States)

    Steinetz, Bruce M.; Dunlap, Patrick H., Jr.

    2000-01-01

    Joints in the Space Shuttle solid rocket motors are sealed by O-rings to contain combustion gases inside the rocket that reach pressures of up to 900 psi and temperatures of up to 5500 F. To provide protection for the O-rings, the motors are insulated with either phenolic or rubber insulation. Gaps in the joints leading up to the O-rings are filled with polysulfide joint-fill compounds as an additional level of protection. The current RSRM nozzle-to-case joint design incorporating primary, secondary, and wiper O-rings experiences gas paths through the joint-fill compound to the innermost wiper O-ring in about one out of every seven motors. Although this does not pose a safety hazard to the motor, it is an undesirable condition that NASA and rocket manufacturer Thiokol want to eliminate. Each nozzle-to-case joint gas path results in extensive reviews and evaluation before flights can be resumed. Thiokol and NASA Marshall are currently working to improve the nozzle-to-case joint design by implementing a more reliable J-leg design that has been used successfully in the field and igniter joint. They are also planning to incorporate the NASA Glenn braided carbon fiber thermal barrier into the joint. The thermal barrier would act as an additional level of protection for the O-rings and allow the elimination of the joint-fill compound from the joint.

  11. Nozzle Flow with Vibrational Nonequilibrium. Ph.D. Thesis

    Science.gov (United States)

    Landry, John Gary

    1995-01-01

    Flow of nitrogen gas through a converging-diverging nozzle is simulated. The flow is modeled using the Navier-Stokes equations that have been modified for vibrational nonequilibrium. The energy equation is replaced by two equations. One equation accounts for energy effects due to the translational and rotational degrees of freedom, and the other accounts for the affects due to the vibrational degree of freedom. The energy equations are coupled by a relaxation time which measures the time required for the vibrational energy component to equilibrate with the translational and rotational energy components. An improved relaxation time is used in this thesis. The equations are solved numerically using the Steger-Warming flux vector splitting method and the Implicit MacCormack method. The results show that uniform flow is produced outside of the boundary layer. Nonequilibrium exists in both the converging and diverging nozzle sections. The boundary layer region is characterized by a marked increase in translational-rotational temperature. The vibrational temperature remains frozen downstream of the nozzle, except in the boundary layer.

  12. Performance of Several Conical Convergent-Divergent Rocket-Type Exhaust Nozzles

    Science.gov (United States)

    Campbell, C. E.; Farley, J. M.

    1960-01-01

    An investigation was conducted to obtain nozzle performance data with relatively large-scale models at pressure ratios as high as 120. Conical convergent-divergent nozzles with divergence angles alpha of 15, 25, and 29 deg. were each tested at area ratios of approximately 10, 25, and 40. Heated air (1200 F) was supplied at the nozzle inlet at pressures up to 145 pounds per square inch absolute and was exhausted into quiescent air at pressures as low as 1.2 pounds per square inch absolute. Thrust ratios for all nozzle configurations are presented over the range of pressure ratios attainable and were extrapolated when possible to design pressure ratio and beyond. Design thrust ratios decreased with increasing nozzle divergence angle according to the trend predicted by the (1 + cos alpha)/2 parameter. Decreasing the nozzle divergence angle resulted in sizable increases in thrust ratio for a given surface-area ratio (nozzle weight), particularly at low nozzle pressure ratios. Correlations of the nozzle static pressure at separation and of the average static pressure downstream of separation with various nozzle parameters permitted the calculation of thrust in the separated-flow region from unseparated static-pressure distributions. Thrust ratios calculated by this method agreed with measured values within about 1 percent.

  13. Design and Checkout of a High Speed Research Nozzle Evaluation Rig

    Science.gov (United States)

    Castner, Raymond S.; Wolter, John D.

    1997-01-01

    The High Flow Jet Exit Rig (HFJER) was designed to provide simulated mixed flow turbojet engine exhaust for one- seventh scale models of advanced High Speed Research test nozzles. The new rig was designed to be used at NASA Lewis Research Center in the Nozzle Acoustic Test Rig and the 8x6 Supersonic Wind Tunnel. Capabilities were also designed to collect nozzle thrust measurement, aerodynamic measurements, and acoustic measurements when installed at the Nozzle Acoustic Test Rig. Simulated engine exhaust can be supplied from a high pressure air source at 33 pounds of air per second at 530 degrees Rankine and nozzle pressure ratios of 4.0. In addition, a combustion unit was designed from a J-58 aircraft engine burner to provide 20 pounds of air per second at 2000 degrees Rankine, also at nozzle pressure ratios of 4.0. These airflow capacities were designed to test High Speed Research nozzles with exhaust areas from eighteen square inches to twenty-two square inches. Nozzle inlet flow measurement is available through pressure and temperature sensors installed in the rig. Research instrumentation on High Speed Research nozzles is available with a maximum of 200 individual pressure and 100 individual temperature measurements. Checkout testing was performed in May 1997 with a 22 square inch ASME long radius flow nozzle. Checkout test results will be summarized and compared to the stated design goals.

  14. Noise Characteristics of Centrifugal Blower with Low Solidity Cascade Diffuser (Noise Reduction by means of Small Groove Located at LSD Blade Leading Tip)

    Institute of Scientific and Technical Information of China (English)

    Tengen MURAKAMI; Masahiro ISHIDA; Daisaku SAKAGUCHI; Yu KOBA

    2009-01-01

    This paper deals with the effect of the blade tip-groove of the low solidity cascade diffuser (LSD) on the blower characteristic and the noise generated by the LSD. The small grooves were set up at the root and/or tip near the leading edge of the LSD blade. In order to clarify the mechanism of noise increase due to LSD and also to reduce the noise, the relationships between the noise increase based on the LSD, the LSD performance and the secondary flow formed additionally by the tip-groove were investigated experimentally as well as numerically, especially analyzing flow behaviors in the LSD in view points of flow separation on the suction surface of the LSD blade and the secondary flow on the side walls. By reducing the stagnation region smaller near the root and/or tip of the LSD blade leading edge, the secondary flow behavior changes remarkably around the LSD blade, as a result, the noise level and the blower characteristics vary. It can be concluded that, by means of a small tip-groove located only at the shroud side near the LSD blade leading edge, the noise generated by the LSD can be reduced without deteriorations of the LSD performance and the blower characteristics as well.

  15. Optimization in the design and efficiency of retractable soot blowers; Optimacion del diseno y la eficiencia de sopladores de hollin retractiles

    Energy Technology Data Exchange (ETDEWEB)

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

    1987-12-31

    In this article the importance of soot blowers in the subject of design, operation and maintenance are described and the effects that its inefficient functioning causes in the steam generators. The activities and the results of a project for the evaluation of the functioning of the soot blowers in the Comision Federal de Electricidad (CFE) boilers. Finally, the scope of a new project oriented towards the retractable soot blowers efficiency optimization, and to the creation of the infra-structure to substitute the import of its components. [Espanol] En este articulo se describe la importancia de los sopladores de hollin en los aspectos de diseno, operacion y mantenimiento, y los efectos que su funcionamiento deficiente produce en los generadores de vapor. Se presentan tambien las actividades y los resultados de un proyecto para evaluar el funcionamiento de los deshollinadores de las calderas de la Comision Federal de Electricidad (CFE). Finalmente, se presenta el alcance de un nuevo proyecto que se orienta a optimar la eficiencia de los sopladores de hollin retractiles y a crear la infraestructura para sustituir las importaciones de sus componentes.

  16. Optimal geometry and dimensions for the receiver of a parabolic solar concentrator with an angle of 90 degrees; Determiancion de la geometria y dimensiones optimas de un receptor para un concentrador solar paraboloidal con angulo de apertura de 90 grados

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, Claudio A; Arancibia, Camilo [Centro de Investigacion en Energia UNAM, Temixco, Morelos (Mexico); Hernandez, Nestor [Centro Nacional de Investigacion y Desarrollo Tecnologico, Cuernavaca, Morelos (Mexico)

    2000-07-01

    The optimal geometry and dimensions for the receiver of a parabolic solar concentrator based on microwave communication antenna are obtained. First, the experiments for the determination of the angular error of the concentrator and the dimensions of its focal region are described. Results are also presented for the ray tracing study, from which the optimal characteristics of the receiver are obtained according to the experimental results. As the aluminum antenna has a rim angle of 90 Celsius degrees, it is necessary to use a cavity receiver to allow external as well as internal absorption of radiative flux. Cylindrical, conical and spherical geometric were considered, as well as combinations of them. The best results are achieved using a conical cavity. Its dimensions are calculated to maximize the radiative transfer efficiency from the aperture of the concentrator to the receiver. [Spanish] Se determinan la geometria y dimensiones optimas del receptor de un concentrador solar parabolico obtenido a partir de una antena de telecomunicaciones para microondas. Primeramente se describen los experimentos realizados para obtener el valor del error angular asociado al concentrador y de las dimensiones de su region focal. Tambien se presentan los resultados del estudio optico de trazado de rayos, que permitio determinar teoricamente las caracteristicas del receptor, de acuerdo a los resultados de los experimentos. Debido a que la antena de aluminio tiene un angulo de borde de 90 grados Celcius, es necesario usar un receptor tipo cavidad que permita la captacion de energia tanto interna como externa. Se consideraron geometrias cilindrica, conica, esferica y combinaciones entre ellas, resultando ser la conica la que da los mejores resultados. Las dimensiones del receptor fueron determinadas maximizando la eficiencia del transporte de radiacion de la apertura del concentrador al receptor.

  17. Analysis to the elements of solar geometry and it relation with the conformation of prehispanic site; Analisis de los elementos de geometria solar y sus relacion con la conformacion de un sitio prehispanico

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Torres, Juan M; Navarrete Padilla, Roberto; Martinez Cossio, Jose L. [Universidad de Guanajuato, Guanjuato, Gto. (Mexico); Castaneda Lopez, Carlos [Instituto Nacional de Antropologia y Historia (INAH), Marfil, Gto. (Mexico)

    2000-07-01

    The first results are presented from the analysis to the general elements of solar geometry in the archaeological place of Plazuelas these elements they are presented as two possible cases, a) the general structure of the place and b) the elements in existent Scale model in the contiguous esplanade to the place that is contemplated above the 400 scale models in the current registrations, of those which approximately 20 present characteristic of design that could be models to scale of other places of great importance for their magnitude and conformation. The astronomical elements initially contemplate alone the relative thing to the limited Solar Geometry mainly for the phase of intervention of the place, which is in the first preliminary works and they have not allowed to discover all the geometric elements of the place, however in this first approach they can be derived some hypotheses of the definition of the same one. [Spanish] Se presentan los primeros resultados del analisis a los elementos generales de geometria solar en el sitio arqueologico de Plazuelas estos elementos se presentan como dos posibles casos, a) la estructura general del sitio y b) los elementos en Maqueta existentes en la explanada contigua al sitio, que en los registros actuales se contempla por encima de las 400 maquetas, de las cuales aproximadamente 20 presentan caracteristicas de diseno que podrian ser modelos a escala de otros sitios de gran importancia por su magnitud y conformacion. Los elementos astronomicos inicialmente contemplan solo lo relativo a la geometria solar limitado principalmente por la fase de intervencion del lugar, el cual se encuentra en los primeros trabajos preliminares y no ha permitido descubrir todos los elementos geometricos del sitio, sin embargo en este primer acercamiento se pueden derivar algunas hipotesis de la definicion del mismo.

  18. Plastic Limit Load Analysis of Cylindrical Pressure Vessels with Different Nozzle Inclination

    Science.gov (United States)

    Prakash, Anupam; Raval, Harit Kishorchandra; Gandhi, Anish; Pawar, Dipak Bapu

    2016-04-01

    Sudden change in geometry of pressure vessel due to nozzle cutout, leads to local stress concentration and deformation, decreasing its strength. Elastic plastic analysis of cylindrical pressure vessels with different inclination angles of nozzle is important to estimate plastic limit load. In the present study, cylindrical pressure vessels with combined inclination of nozzles (i.e. in longitudinal and radial plane) are considered for elastic plastic limit load analysis. Three dimensional static nonlinear finite element analyses of cylindrical pressure vessels with nozzle are performed for incremental pressure loading. The von Mises stress distribution on pressure vessel shows higher stress zones at shell-nozzle junction. Approximate plastic limit load is obtained by twice elastic slope method. Variation in limit pressure with different combined inclination angle of nozzle is analyzed and found to be distinct in nature. Reported results can be helpful in optimizing pressure vessel design.

  19. Effect of Nozzle Material on Downstream Lateral Injection Cold Spray Performance

    Science.gov (United States)

    MacDonald, D.; Leblanc-Robert, S.; Fernández, R.; Farjam, A.; Jodoin, B.

    2016-08-01

    In cold gas dynamic spraying, the gas nature, process stagnation pressure and temperature, and the standoff distance are known to be important parameters that affect the deposition efficiency and coating quality. This investigation attempts to elucidate the effect of nozzle material on coatings produced using a downstream lateral injection cold spray system. Through experimentation, it is shown that the nozzle material has a substantial effect on deposition efficiency and particle velocity. It is proposed that the effects are related to complex interaction between the particles and the internal nozzle walls. The results obtained lead to the conclusion that during the particle/nozzle wall contact, a nozzle with higher thermal diffusivity transfers more heat to the particles. This heat transfer results in lower critical velocities and therefore higher deposition efficiencies, despite a noticeable reduction of particle velocities which is also attributed to particle-nozzle interactions.

  20. Static internal performance including thrust vectoring and reversing of two-dimensional convergent-divergent nozzles

    Science.gov (United States)

    Re, R. J.; Leavitt, L. D.

    1984-01-01

    The effects of geometric design parameters on two dimensional convergent-divergent nozzles were investigated at nozzle pressure ratios up to 12 in the static test facility. Forward flight (dry and afterburning power settings), vectored-thrust (afterburning power setting), and reverse-thrust (dry power setting) nozzles were investigated. The nozzles had thrust vector angles from 0 deg to 20.26 deg, throat aspect ratios of 3.696 to 7.612, throat radii from sharp to 2.738 cm, expansion ratios from 1.089 to 1.797, and various sidewall lengths. The results indicate that unvectored two dimensional convergent-divergent nozzles have static internal performance comparable to axisymmetric nozzles with similar expansion ratios.

  1. Simulation of Cold Flow in a Truncated Ideal Nozzle with Film Cooling

    Science.gov (United States)

    Braman, K. E.; Ruf, J. H.

    2015-01-01

    Flow transients during rocket start-up and shut-down can lead to significant side loads on rocket nozzles. The capability to estimate these side loads computationally can streamline the nozzle design process. Towards this goal, the flow in a truncated ideal contour (TIC) nozzle has been simulated using RANS and URANS for a range of nozzle pressure ratios (NPRs) aimed to match a series of cold flow experiments performed at the NASA MSFC Nozzle Test Facility. These simulations were performed with varying turbulence model choices and for four approximations of the supersonic film injection geometry, each of which was created with a different simplification of the test article geometry. The results show that although a reasonable match to experiment can be obtained with varying levels of geometric fidelity, the modeling choices made do not fully represent the physics of flow separation in a TIC nozzle with film cooling.

  2. Development of automated nondestructive inspection system for BMI nozzles in nuclear vessel

    Energy Technology Data Exchange (ETDEWEB)

    Park, Joon Soo; Lee, Won Kun; Han, Won Jin; Lee, Sun Ho; Seong, Un Hak [Doosan Heavy Industries and Construction Co., Ltd., Changwon (Korea, Republic of)

    2013-02-15

    BMI nozzles in bottom head of the nuclear vessel are one of major components in nuclear power plants. The BMI nozzles have high possibility to generate PWSCC(primary water stress corrosion crack) according to recent foreign case although operation temperature is lower then the upper head of the nuclear vessel. Thus, nondestructive inspection of the BMI nozzles is required. But, inspection of BMI nozzles is not easy since the BMI nozzles placed in high radiated area and inside the nozzles filled with boric acid. Thus, in this study, a TOFD transducer for inspection of BMI and automated scanner system with water were developed. Also, validation of performance of the developed transducer and system are performed using specimens with artificial defects.

  3. 燃煤炉鼓风机中变频器的节能分析%Energy conservation analysis of the inverter in coal-fired furnace blower

    Institute of Scientific and Technical Information of China (English)

    武欣

    2011-01-01

    In order to lower the power consumption rate of coal-fired furnace blower, to reduce the starting current, to increase the power factor, and to improve the fireman's working intensity, frequency converter was proposed to be used in coal-fired furnace blower. Compared to the traditional coal-fired furnace blower system,this system used converter to control the flow (air volume), which could save a lot of power. Through a detailed analysis of the pressure H-flow Q curve, it is clear that after the frequency conversion, the required power of blower is reduced. Meanwhile, the soft-start function of the converter and the feature of smooth speed governing could realized the smooth adjustment of the system,which made the system worked stable and extended the service life of various components of the boiler. Finally, the practice data shows it is energy-efficient to use the frequency converter in coal-fired furnace blower.%为了降低燃煤炉鼓风机的用电率、减少起动电流、提高功率因数、改善司炉工工作强度,提出了将变频器用在燃煤炉鼓风机中.与传统的燃煤炉鼓风机系统相比较,该系统利用变频器进行流量(风量)控制时,可节约大量电能.通过详细分析压力H-流量Q曲线,得出变频调速后风机所需功率明显减少.同时,变频器的软启动功能和平滑调速的特点可实现对系统的平稳调节,使系统工作状态稳定,延长锅炉各部件的使用寿命.最后通过实际数据可知使用变频器后的燃煤炉鼓风机是节能的.

  4. Effects of varying podded nacelle-nozzle installations on transonic aeropropulsive characteristics of a supersonic fighter aircraft

    Science.gov (United States)

    Capone, F. J.; Reubush, D. E.

    1983-01-01

    The aeropropulsive characteristics of an advanced twin engine fighter designed for supersonic cruise was investigated in the 16 foot Transonic Tunnel. The performance characteristics of advanced nonaxisymmetric nozzles installed in various nacelle locations, the effects of thrust induced forces on overall aircraft aerodynamics, the trim characteristics, and the thrust reverser performance were evaluated. The major model variables included nozzle power setting; nozzle duct aspect ratio; forward, mid, and aft nacelle axial locations; inboard and outboard underwing nacelle locations; and underwing and overwing nacelle locations. Thrust vectoring exhaust nozzle configurations included a wedge nozzle, a two dimensional convergent divergent nozzle, and a single expansion ramp nozzle, each with deflection angles up to 30 deg. In addition to the nonaxisymmetric nozzles, an axisymmetric nozzle installation was also tested. The use of a canard for trim was also assessed.

  5. The Effect of Fuel Injector Nozzle Configuration on JP-8 Sprays at Diesel Engine Conditions

    Science.gov (United States)

    2014-10-01

    The Effect of Fuel Injector Nozzle Configuration on JP-8 Sprays at Diesel Engine Conditions by Matthew Kurman, Luis Bravo, Chol-Bum Kweon...Fuel Injector Nozzle Configuration on JP-8 Sprays at Diesel Engine Conditions Matthew Kurman, Luis Bravo, and Chol-Bum Kweon Vehicle Technology...March 2014 4. TITLE AND SUBTITLE The Effect of Fuel Injector Nozzle Configuration on JP-8 Sprays at Diesel Engine Conditions 5a. CONTRACT NUMBER 5b

  6. Diffusive self-ignition of hydrogen upon efflux from a nozzle array

    Science.gov (United States)

    Golub, V. V.; Bazhenova, T. V.; Laskin, I. N.; Semin, N. V.

    2009-03-01

    It is experimentally demonstrated that the efflux of hydrogen at a high pressure into air via a nozzle array is accompanied by the interaction of jets, which results in the conditions for self-ignition at a nozzle diameter below the values for which self-ignition is possible in a single jet. Conditions for the safe efflux of hydrogen via a nozzle array from a reservoir at a pressure of 400 bar (and below) are established.

  7. Non-local electron energy probability function in a plasma expanding along a magnetic nozzle.

    Directory of Open Access Journals (Sweden)

    Roderick William Boswell

    2015-03-01

    Full Text Available Electron energy probability functions (eepfs have been measured along the axis of low pressure plasma expanding in a magnetic nozzle. The eepf at the maximum magnetic field of the nozzle shows a depleted tail commencing at an energy corresponding to the measured potential drop in the magnetic nozzle. The eepfs measured along the axis demonstrate that the potential and kinetic energies of the electrons are conserved and confirm the non-local collisionless kinetics of the electron dynamics.

  8. Flow visualization and interpretation of visualization data for deflected thrust V/STOL nozzles

    Science.gov (United States)

    Kao, H. C.; Burstadt, P. L.; Johns, A. L.

    1984-01-01

    Flow visualization studies were made for four deflected thrust nozzle models at subsonic speeds. Based on topological rules and the assumption that observed streaks constitute continuous vector fields, available visualization pictures are interpreted and flow patterns on interior surfaces of the nozzles are synthesized. In particular, three dimensional flow structure and separations are discussed. From the synthesized patterns, the overall features of the flow field in a given nozzle can be approximately perceived. Previously announced in STAR as N84-14147

  9. Parametric investigation of single-expansion-ramp nozzles at Mach numbers from 0.60 to 1.20

    Science.gov (United States)

    Capone, Francis J.; Re, Richard J.; Bare, E. Ann

    1992-01-01

    An investigation was conducted in the Langley 16-Foot Transonic Tunnel to determine the effects of varying six nozzle geometric parameters on the internal and aeropropulsive performance characteristics of single-expansion-ramp nozzles. This investigation was conducted at Mach numbers from 0.60 to 1.20, nozzle pressure ratios from 1.5 to 12, and angles of attack of 0 deg +/- 6 deg. Maximum aeropropulsive performance at a particular Mach number was highly dependent on the operating nozzle pressure ratio. For example, as the nozzle upper ramp length or angle increased, some nozzles had higher performance at a Mach number of 0.90 because of the nozzle design pressure was the same as the operating pressure ratio. Thus, selection of the various nozzle geometric parameters should be based on the mission requirements of the aircraft. A combination of large upper ramp and large lower flap boattail angles produced greater nozzle drag coefficients at Mach number greater than 0.80, primarily from shock-induced separation on the lower flap of the nozzle. A static conditions, the convergent nozzle had high and nearly constant values of resultant thrust ratio over the entire range of nozzle pressure ratios tested. However, these nozzles had much lower aeropropulsive performance than the convergent-divergent nozzle at Mach number greater than 0.60.

  10. Formation of Vortex Structures in the Prenozzle Space of an Engine with a Vectorable Thrust Nozzle

    Science.gov (United States)

    Volkov, K. N.; Emel'yanov, V. N.; Denisikhin, S. V.

    2016-05-01

    A numerical simulation of the hydrodynamic effects arising in the process of work of the vectorable thrust nozzle of a solid-propellant rocket engine has been performed. The fields of the flows of combustion products in the channel of a charge, the prenozzle space, and the nozzle unit were calculated for different angles of vectoring of the nozzle. The distributions of the gasdynamic parameters of the flow of combustion products in the prenozzle space, corresponding to their efflux from the cylindrical and star-shaped channels of charges, were compared. The formation of a vortex flow in the neighborhood of the back cover of the nozzle was considered.

  11. Design and development of SiC/(W, Ti)C gradient ceramic nozzle

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The idea of functionally gradient material (FGM) theory was used to design ceramic nozzle based on the erosion wear behaviors of the ceramic nozzles and the outstanding properties of FGM. The purpose is to reduce the tensile stress at the entry region of the nozzle during sand blasting processes. The design theory and methods of gradient ceramic nozzle were proposed. The physical, micromechanical, and composition distribution models of gradient ceramic nozzle were established. The optimum composition distribution of the gradient ceramic nozzle material was determined from the solution of the multi-objective optimization calculation by constructing the models of the composition distribution versus the structural integrity of the compact in fabricating process. Results showed that compressive residual stresses appeared at the entry area of the gradient ceramic nozzle. The optimized component distribution exponent p is 0.5. An SiC/(W,Ti)C gradient ceramic nozzle material was synthesized by hot-pressing according to the design result. Results showed that the surface Vickers hardness of the FGM-1 gradient ceramic nozzle materials was greatly improved in comparison with that of the other layers.

  12. Numerical Investigation of Jet Noise Prediction in Exhaust Nozzle by Passive Control Techniques

    Directory of Open Access Journals (Sweden)

    Alagu sundaram.A

    2015-05-01

    Full Text Available The project mainly focuses on the reduction of jet noise emission in the exhaust nozzle of TURBOFAN ENGINES. Reduction of noise in the exhaust system is done by attaching chevrons with particular parameters in the nozzle exit. Numerical investigations have been carried out on chevron nozzles to assess the importance of chevron parameters such as the number of chevrons like (chevron count, chevron penetration and the mixing characteristics of co flow jet. Chevron count is the pertinent parameter for noise reduction at low nozzle pressure ratios, whereas at high nozzle pressure ratios, chevron penetration is crucial. The results illustrate that by careful selection of chevron parameters substantial noise reduction can be achieved. The sound pressure level (SPL can be calculated from that we determined the noise level at nozzle exit section. After assessing the chevron parameters we are going to modify the chevron shapes in order to get maximum noise reduction along with very negligible thrust loss. Modification of chevron is based on aspect of increasing the mixing of cold jet and the hot jet in order to decrease the noise emission. ANSYS-Fluent is a commercial CFD code which will be used for performing the simulation and the simulation configuration contains three different velocities (100,150,200 with two different nozzle model(plain & chevron nozzle. The simulation results are evaluated to find out nozzle noise level in the engine exhaust system.

  13. Comparison of CFD Simulations with Experimental Measurements of Nozzle Clogging in Continuous Casting of Steels

    Science.gov (United States)

    Mohammadi-Ghaleni, Mahdi; Asle Zaeem, Mohsen; Smith, Jeffrey D.; O'Malley, Ronald

    2016-12-01

    Measurements of clog deposit thickness on the interior surfaces of a commercial continuous casting nozzle are compared with computational fluid dynamics (CFD) predictions of melt flow patterns and particle-wall interactions to identify the mechanisms of nozzle clogging. A submerged entry nozzle received from industry was encased in epoxy and carefully sectioned to allow measurement of the deposit thickness on the internal surfaces of the nozzle. CFD simulations of melt flow patterns and particle behavior inside the nozzle were performed by combining the Eulerian-Lagrangian approach and detached eddy simulation turbulent model, matching the geometry and operating conditions of the industrial test. The CFD results indicated that convergent areas of the interior cross section of the nozzle increased the velocity and turbulence of the flowing steel inside the nozzle and decreased the clog deposit thickness locally in these areas. CFD simulations also predicted a higher rate of attachment of particles in the divergent area between two convergent sections of the nozzle, which matched the observations made in the industrial nozzle measurements.

  14. Numerical analysis of Chevron nozzle effects on performance of the supersonic ejector-diffuser system

    Science.gov (United States)

    Kong, Fanshi; Jin, Yingzi; Setoguchi, Toshiaki; Kim, Heuy Dong

    2013-10-01

    The supersonic nozzle is the most important device of an ejector-diffuser system. The best operation condition and optimal structure of supersonic nozzle are hardly known due to the complicated turbulent mixing, compressibility effects and even flow unsteadiness which are generated around the nozzle extent. In the present study, the primary stream nozzle was redesigned using convergent nozzle to activate the shear actions between the primary and secondary streams, by means of longitudinal vortices generated between the Chevron lobes. Exactly same geometrical model of ejector-diffuser system was created to validate the results of experimental data. The operation characteristics of the ejector system were compared between Chevron nozzle and conventional convergent nozzle for the primary stream. A CFD method has been applied to simulate the supersonic flows and shock waves inside the ejector. It is observed that the flow structure and shock system were changed and primary numerical analysis results show that the Chevron nozzle achieve a positive effect on the supersonic ejector-diffuser system performance. The ejector with Chevron nozzle can entrain more secondary stream with less primary stream mass flow rate.

  15. Free-jet acoustic investigation of high-radius-ratio coannular plug nozzles

    Science.gov (United States)

    Knott, P. R.; Janardan, B. A.; Majjigi, R. K.; Bhutiani, P. K.; Vogt, P. G.

    1984-01-01

    The experimental and analytical results of a scale model simulated flight acoustic exploratory investigation of high radius ratio coannular plug nozzles with inverted velocity and temperature profiles are summarized. Six coannular plug nozzle configurations and a baseline convergent conical nozzle were tested for simulated flight acoustic evaluation. The nozzles were tested over a range of test conditions that are typical of a Variable Cycle Engine for application to advanced high speed aircraft. It was found that in simulate flight, the high radius ratio coannular plug nozzles maintain their jet noise and shock noise reduction features previously observed in static testing. The presence of nozzle bypass struts will not significantly affect the acousticn noise reduction features of a General Electric type nozzle design. A unique coannular plug nozzle flight acoustic spectral prediction method was identified and found to predict the measured results quite well. Special laser velocimeter and acoustic measurements were performed which have given new insights into the jet and shock noise reduction mechanisms of coannular plug nozzles with regard to identifying further benificial research efforts.

  16. Transonic Investigation of Two-Dimensional Nozzles Designed for Supersonic Cruise

    Science.gov (United States)

    Capone, Francis J.; Deere, Karen A.

    2015-01-01

    An experimental and computational investigation has been conducted to determine the off-design uninstalled drag characteristics of a two-dimensional convergent-divergent nozzle designed for a supersonic cruise civil transport. The overall objectives were to: (1) determine the effects of nozzle external flap curvature and sidewall boattail variations on boattail drag; (2) develop an experimental data base for 2D nozzles with long divergent flaps and small boattail angles and (3) provide data for correlating computational fluid dynamic predictions of nozzle boattail drag. The experimental investigation was conducted in the Langley 16-Foot Transonic Tunnel at Mach numbers from 0.80 to 1.20 at nozzle pressure ratios up to 9. Three-dimensional simulations of nozzle performance were obtained with the computational fluid dynamics code PAB3D using turbulence closure and nonlinear Reynolds stress modeling. The results of this investigation indicate that excellent correlation between experimental and predicted results was obtained for the nozzle with a moderate amount of boattail curvature. The nozzle with an external flap having a sharp shoulder (no curvature) had the lowest nozzle pressure drag. At a Mach number of 1.2, sidewall pressure drag doubled as sidewall boattail angle was increased from 4deg to 8deg. Reducing the height of the sidewall caused large decreases in both the sidewall and flap pressure drags. Summary

  17. Static internal performance of a two-dimensional convergent-divergent nozzle with thrust vectoring

    Science.gov (United States)

    Bare, E. Ann; Reubush, David E.

    1987-01-01

    A parametric investigation of the static internal performance of multifunction two-dimensional convergent-divergent nozzles has been made in the static test facility of the Langley 16-Foot Transonic Tunnel. All nozzles had a constant throat area and aspect ratio. The effects of upper and lower flap angles, divergent flap length, throat approach angle, sidewall containment, and throat geometry were determined. All nozzles were tested at a thrust vector angle that varied from 5.60 tp 23.00 deg. The nozzle pressure ratio was varied up to 10 for all configurations.

  18. Computational Study of an Axisymmetric Dual Throat Fluidic Thrust Vectoring Nozzle for a Supersonic Aircraft Application

    Science.gov (United States)

    Deere, Karen A.; Flamm, Jeffrey D.; Berrier, Bobby L.; Johnson, Stuart K.

    2007-01-01

    A computational investigation of an axisymmetric Dual Throat Nozzle concept has been conducted. This fluidic thrust-vectoring nozzle was designed with a recessed cavity to enhance the throat shifting technique for improved thrust vectoring. The structured-grid, unsteady Reynolds- Averaged Navier-Stokes flow solver PAB3D was used to guide the nozzle design and analyze performance. Nozzle design variables included extent of circumferential injection, cavity divergence angle, cavity length, and cavity convergence angle. Internal nozzle performance (wind-off conditions) and thrust vector angles were computed for several configurations over a range of nozzle pressure ratios from 1.89 to 10, with the fluidic injection flow rate equal to zero and up to 4 percent of the primary flow rate. The effect of a variable expansion ratio on nozzle performance over a range of freestream Mach numbers up to 2 was investigated. Results indicated that a 60 circumferential injection was a good compromise between large thrust vector angles and efficient internal nozzle performance. A cavity divergence angle greater than 10 was detrimental to thrust vector angle. Shortening the cavity length improved internal nozzle performance with a small penalty to thrust vector angle. Contrary to expectations, a variable expansion ratio did not improve thrust efficiency at the flight conditions investigated.

  19. Static performance of nonaxisymmetric nozzles with yaw thrust-vectoring vanes

    Science.gov (United States)

    Mason, Mary L.; Berrier, Bobby L.

    1988-01-01

    A static test was conducted in the static test facility of the Langley 16 ft Transonic Tunnel to evaluate the effects of post exit vane vectoring on nonaxisymmetric nozzles. Three baseline nozzles were tested: an unvectored two dimensional convergent nozzle, an unvectored two dimensional convergent-divergent nozzle, and a pitch vectored two dimensional convergent-divergent nozzle. Each nozzle geometry was tested with 3 exit aspect ratios (exit width divided by exit height) of 1.5, 2.5 and 4.0. Two post exit yaw vanes were externally mounted on the nozzle sidewalls at the nozzle exit to generate yaw thrust vectoring. Vane deflection angle (0, -20 and -30 deg), vane planform and vane curvature were varied during the test. Results indicate that the post exit vane concept produced resultant yaw vector angles which were always smaller than the geometric yaw vector angle. Losses in resultant thrust ratio increased with the magnitude of resultant yaw vector angle. The widest post exit vane produced the largest degree of flow turning, but vane curvature had little effect on thrust vectoring. Pitch vectoring was independent of yaw vectoring, indicating that multiaxis thrust vectoring is feasible for the nozzle concepts tested.

  20. Static performance of an axisymmetric nozzle with post-exit vanes for multiaxis thrust vectoring

    Science.gov (United States)

    Berrier, Bobby L.; Mason, Mary L.

    1988-01-01

    An investigation was conducted in the static test facility of the Langley 16-Foot Transonic Tunnel to determine the flow-turning capability and the nozzle internal performance of an axisymmetric convergent-divergent nozzle with post-exit vanes installed for multiaxis thrust vectoring. The effects of vane curvature, vane location relative to the nozzle exit, number of vanes, and vane deflection angle were determined. A comparison of the post-exit-vane thrust-vectoring concept with other thrust-vectoring concepts is provided. All tests were conducted with no external flow, and nozzle pressure ratio was varied from 1.6 to 6.0.

  1. Direct Numerical Simulation of Hypersonic Turbulent Boundary Layer inside an Axisymmetric Nozzle

    Science.gov (United States)

    Huang, Junji; Zhang, Chao; Duan, Lian; Choudhari, Meelan M.

    2017-01-01

    As a first step toward a study of acoustic disturbance field within a conventional, hypersonic wind tunnel, direct numerical simulations (DNS) of a Mach 6 turbulent boundary layer on the inner wall of a straight axisymmetric nozzle are conducted and the results are compared with those for a flat plate. The DNS results for a nozzle radius to boundary-layer thickness ratio of 5:5 show that the turbulence statistics of the nozzle-wall boundary layer are nearly unaffected by the transverse curvature of the nozzle wall. Before the acoustic waves emanating from different parts of the nozzle surface can interfere with each other and undergo reflections from adjacent portions of the nozzle surface, the rms pressure fluctuation beyond the boundary layer edge increases toward the nozzle axis, apparently due to a focusing effect inside the axisymmetric configuration. Spectral analysis of pressure fluctuations at both the wall and the freestream indicates a similar distribution of energy content for both the nozzle and the flat plate, with the peak of the premultiplied frequency spectrum at a frequency of [(omega)(delta)]/U(sub infinity) approximately 6.0 inside the free stream and at [(omega)(delta)]/U(sub infinity) approximately 2.0 along the wall. The present results provide the basis for follow-on simulations involving reverberation effects inside the nozzle.

  2. Injector Nozzle Flow Model and Its Effects on the Calculations of High Pressure Sprays

    Institute of Scientific and Technical Information of China (English)

    WEI Ming-rui; LIU Yong-chang; WEN Hua; ZHANG Yue-heng

    2004-01-01

    This paper discusses the flowing process inside a nozzle, especially the formation mechanism of cavitations within the nozzle and puts forward a nozzle flow model, which takes account of the injection conditions and nozzle geometry. By the model being implemented to the KIVA codes, the spray characteristics (e.g., spray penetration and cone angle) of diesel and dimethyl ether (DME) are simulated. The comparisons between the computational and experimental results are performed, which show that the liquid spray characteristics could be more truly demonstrated by considering the existence of the cavitations.

  3. Interior flow and near-nozzle spray development in a marine-engine diesel fuel injector

    Science.gov (United States)

    Hult, J.; Simmank, P.; Matlok, S.; Mayer, S.; Falgout, Z.; Linne, M.

    2016-04-01

    A consolidated effort at optically characterising flow patterns, in-nozzle cavitation, and near-nozzle jet structure of a marine diesel fuel injector is presented. A combination of several optical techniques was employed to fully transparent injector models, compound metal-glass and full metal injectors. They were all based on a common real-scale dual nozzle hole geometry for a marine two-stroke diesel engine. In a stationary flow rig, flow velocities in the sac-volume and nozzle holes were measured using PIV, and in-nozzle cavitation visualized using high-resolution shadowgraphs. The effect of varying cavitation number was studied and results compared to CFD predictions. In-nozzle cavitation and near-nozzle jet structure during transient operation were visualized simultaneously, using high-speed imaging in an atmospheric pressure spray rig. Near-nozzle spray formation was investigated using ballistic imaging. Finally, the injector geometry was tested on a full-scale marine diesel engine, where the dynamics of near-nozzle jet development was visualized using high-speed shadowgraphy. The range of studies focused on a single common geometry allows a comprehensive survey of phenomena ranging from first inception of cavitation under well-controlled flow conditions to fuel jet structure at real engine conditions.

  4. An Interactive Method of Characteristics Java Applet to Design and Analyze Supersonic Aircraft Nozzles

    Science.gov (United States)

    Benson, Thomas J.

    2014-01-01

    The Method of Characteristics (MOC) is a classic technique for designing supersonic nozzles. An interactive computer program using MOC has been developed to allow engineers to design and analyze supersonic nozzle flow fields. The program calculates the internal flow for many classic designs, such as a supersonic wind tunnel nozzle, an ideal 2D or axisymmetric nozzle, or a variety of plug nozzles. The program also calculates the plume flow produced by the nozzle and the external flow leading to the nozzle exit. The program can be used to assess the interactions between the internal, external and plume flows. By proper design and operation of the nozzle, it may be possible to lessen the strength of the sonic boom produced at the rear of supersonic aircraft. The program can also calculate non-ideal nozzles, such as simple cone flows, to determine flow divergence and nonuniformities at the exit, and its effect on the plume shape. The computer program is written in Java and is provided as free-ware from the NASA Glenn central software server.

  5. Design and development of SiC/(W,Ti)C gradient ceramic nozzle

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The idea of functionally gradient material (FGM) theory was used to design ceramic nozzle based on the erosion wear behaviors of the ceramic nozzles and the out- standing properties of FGM. The purpose is to reduce the tensile stress at the entry region of the nozzle during sand blasting processes. The design theory and methods of gradient ceramic nozzle were proposed. The physical, micromechanical, and composition distribution models of gradient ceramic nozzle were established. The optimum composition distribution of the gradient ceramic nozzle material was determined from the solution of the multi-objective optimization calculation by constructing the models of the composition distribution versus the structural in- tegrity of the compact in fabricating process. Results showed that compressive residual stresses appeared at the entry area of the gradient ceramic nozzle. The optimized component distribution exponent p is 0.5. An SiC/(W,Ti)C gradient ce- ramic nozzle material was synthesized by hot-pressing according to the design result. Results showed that the surface Vickers hardness of the FGM-1 gradient ceramic nozzle materials was greatly improved in comparison with that of the other layers.

  6. Comparison of CFD Simulations with Experimental Measurements of Nozzle Clogging in Continuous Casting of Steels

    Science.gov (United States)

    Mohammadi-Ghaleni, Mahdi; Asle Zaeem, Mohsen; Smith, Jeffrey D.; O'Malley, Ronald

    2016-08-01

    Measurements of clog deposit thickness on the interior surfaces of a commercial continuous casting nozzle are compared with computational fluid dynamics (CFD) predictions of melt flow patterns and particle-wall interactions to identify the mechanisms of nozzle clogging. A submerged entry nozzle received from industry was encased in epoxy and carefully sectioned to allow measurement of the deposit thickness on the internal surfaces of the nozzle. CFD simulations of melt flow patterns and particle behavior inside the nozzle were performed by combining the Eulerian-Lagrangian approach and detached eddy simulation turbulent model, matching the geometry and operating conditions of the industrial test. The CFD results indicated that convergent areas of the interior cross section of the nozzle increased the velocity and turbulence of the flowing steel inside the nozzle and decreased the clog deposit thickness locally in these areas. CFD simulations also predicted a higher rate of attachment of particles in the divergent area between two convergent sections of the nozzle, which matched the observations made in the industrial nozzle measurements.

  7. State and heat up of the gas in regenerative blowers; Zustandsaenderung und Aufheizung des Gases in Seitenkanalverdichtern

    Energy Technology Data Exchange (ETDEWEB)

    Surek, D. [Fachbereich Maschinenbau, Fachhochschule Merseburg (Germany); Galinsky, H. [Fachbereich Maschinenbau, Fachhochschule Merseburg (Germany)

    1995-05-01

    Regenerative blowers have thermical loads in spite of their low pressure ratio. On the basis of the compression-end temperature the machine load are increased. An increasing machine temperature heat up of the gas at the input in the machine, which influences the energy transfer. The results of practical investigations have shown that the heating-up process in the entering part of the side channel and in the front part are so that the energy transfer will have many loses. Among these are very high polytropic exponents with high pressure ratio in the particle load, which increase the heat transfer to the gas and lower the efficiency of the machine. (orig.) [Deutsch] Seitenkanalverdichter unterliegen trotz ihrer geringen Druckverhaeltnisse im Teillastbereich erheblichen thermischen Belastungen. Dadurch steigt nicht nur die Verdichtungsendtemperatur und die Maschinenbelastung, sondern mit steigender Maschinentemperatur erfolgt auch eine erhebliche Aufheizung des Gases bereits im Eintrittsbereich, wodurch die Arbeitsuebertragung beeinflusst wird. Die Resultate experimenteller Untersuchungen zeigen, dass die Aufheizung des Gases besonders im Eintrittsbereich des Seitenkanals erfolgt und dadurch die Arbeitsuebertragung im vorderen Bereich stark verlustbehaftet erfolgt. Die Folge davon sind sehr hohe Polytropenexponenten bei grossen Druckverhaeltnissen im Teillastbereich, die zu einer grossen Waermezufuhr an das Gas fuehren und den Wirkungsgrad der Maschinen mindern. (orig.)

  8. Design instructions for condensers and recirculation coolers with axial blowers; Auslegungshinweis fuer Verfluessiger und Rueckkuehler mit Axialventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Handschuh, R. [Hans Guentner GmbH, Fuerstenfeldbruck (Germany)

    2003-07-01

    Apart from an explanation of the selectrion criteria for condensers and recirculation coolers with axial blowers for outside installation, information is presented on sound propagation. Selection according to the condensing capacity O{sub c}, the recooling rate Q{sub H} and the available floor space can be made with the aid of the Guentner Product Calculator GPC. Permissible noise emissions and adjacent installation of condensers and recoolers are gone into as well as noise propagation as a function of external noise, noise direction, noise reflection, the number of noise sources, the distance of the noise source from the emission point, and possible noise abatement factors are gone into as well. (orig.) [German] Neben der Erlaeuterung der Auswahlkriterien fuer Verfluessiger und Rueckkuehler mit Axialventilatoren zur Aufstellung im Freien werden Hinweise fuer die Schallausbreitung gegeben. Die Auswahl nach der Verfluessigungsleistung Q{sub c} bzw. der Rueckkuehlleistung Q{sub H} und der vorhandenen Aufstellflaeche kann mit dem Guentner Product Calculator GPC geschehen. Es wird auf die zulaessige Geraeuschimmission auf die Nachbarschaft von Verfluessigern und Rueckkuehlern eingegangen und deren Schallausbreitung in Abhaengigkeit von Fremdgeraeuscheinwirkungen, Schallrichtwirkung, der Schallreflexion, der Anzahl der Schallquellen, der Entfernung der Schallquelle zur Emissionsstelle und moegliche Daempfungen betrachtet. (orig.)

  9. Optimal DO Setpoint Decision and Electric Cost Saving in Aerobic Reactor Using Respirometer and Air Blower Control

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kwang Su; Yoo, Changkyoo [Kyung Hee University, Yongin (Korea, Republic of); Kim, Minhan [Pangaea21 Ltd., Seongnam (Korea, Republic of); Kim, Jongrack [UnUsoft Ltd., Seoul (Korea, Republic of)

    2014-10-15

    Main objects for wastewater treatment operation are to maintain effluent water quality and minimize operation cost. However, the optimal operation is difficult because of the change of influent flow rate and concentrations, the nonlinear dynamics of microbiology growth rate and other environmental factors. Therefore, many wastewater treatment plants are operated for much more redundant oxygen or chemical dosing than the necessary. In this study, the optimal control scheme for dissolved oxygen (DO) is suggested to prevent over-aeration and the reduction of the electric cost in plant operation while maintaining the dissolved oxygen (DO) concentration for the metabolism of microorganisms in oxic reactor. The oxygen uptake rate (OUR) is real-time measured for the identification of influent characterization and the identification of microorganisms' oxygen requirement in oxic reactor. Optimal DO set-point needed for the micro-organism is suggested based on real-time measurement of oxygen uptake of micro-organism and the control of air blower. Therefore, both stable effluent quality and minimization of electric cost are satisfied with a suggested optimal set-point decision system by providing the necessary oxygen supply requirement to the micro-organisms coping with the variations of influent loading.

  10. Thrust Enhancement in Hypervelocity Nozzles by Chemical Catalysis

    Science.gov (United States)

    Singh, D. J.; Carpenter, Mark H.; Drummond, J. P.

    1997-01-01

    In the hypersonic flight regime, the air-breathing supersonic combustion ramjet (scramjet) has been shown to be a viable propulsion system. The current designs of scramjet engines provide performance benefits only up to a Mach number of 14. Performance losses increase rapidly as the Mach number increases. To extend the applicability of scram'jets beyond Mach 14, research is being conducted in the area of inlet and wave drag reduction, skin-friction and heat-transfer reduction, nozzle loss minimization, low-loss mixing, and combustion enhancement. For high Mach number applications, hydrogen is the obvious fuel choice because of its high energy content per unit mass in comparison with conventional fuels. These flight conditions require engines to operate at supersonic internal velocities, high combustor temperatures, and low static pressures. The high static temperature condition enhances the production of radicals such as H and OH, and the low-pressure condition slows the reaction rates, particularly the recombination reactions. High-temperature and low-pressure constraints, in combination with a small residence time, result in a radical-rich exhaust gas mixture exiting the combustor. At high Mach number conditions (due to low residence time), H and OH do not have enough time to recombine ; thus, a significant amount of energy is lost as these high-energy free radical are exhausted. The objective of the present study is to conduct a flowfield analysis for a typical nozzle geometry for NASP-type vehicle to assess for thrust enhancement in hypervelocity nozzles by substituting small amount of phosphine for hydrogen.

  11. Fluidically Augmented Nozzles for Pulse Detonation Engine Applications

    Science.gov (United States)

    2011-12-01

    Nozzles 15. NUMBER OF PAGES 147 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT Unclassified 18. SECURITY CLASSIFICATION OF THIS PAGE...COOH tpis91 *C2 g 6/01 C2H g 1/91 C2H2, acetylene g 5/01 C2H2,vinylidene g 4/02 CH2CO,ketene g 3/02... acetylene C2H2,vinylidene CH2CO,ketene O(CH)2O HO(CO)2OH C2H3,vinyl CH3CN CH3CO,acetyl C2H4 C2H4O,ethylen

  12. Two-phase nozzle flow and the subcharacteristic condition

    DEFF Research Database (Denmark)

    Linga, Gaute; Aursand, Peder; Flåtten, Tore

    2015-01-01

    We consider nozzle flow models for two-phase flow with phase transfer. Such models are based on energy considerations applied to the frozen and equilibrium limits of the underlying relaxation models. In this paper, we provide an explicit link between the mass flow rate predicted by these models a...... leakage of CO2 is presented, indicating that the frozen and equilibrium models provide significantly different predictions. This difference is comparable in magnitude to the modeling error introduced by applying simple ideal-gas/incompressible-liquid equations-of-state for CO2....

  13. An Investigation of Transonic Resonance in a Mach 2.2 Round Convergent-Divergent Nozzle

    Science.gov (United States)

    Dippold, Vance F., III; Zaman, Khairul B. M. Q.

    2015-01-01

    Hot-wire and acoustic measurements were taken for a round convergent nozzle and a round convergent-divergent (C-D) nozzle at a jet Mach number of 0.61. The C-D nozzle had a design Mach number of 2.2. Compared to the convergent nozzle jet flow, the Mach 2.2 nozzle jet flow produced excess broadband noise (EBBN). It also produced a transonic resonance tone at 1200 Herz. Computational simulations were performed for both nozzle flows. A steady Reynolds-Averaged Navier-Stokes simulation was performed for the convergent nozzle jet flow. For the Mach 2.2 nozzle flow, a steady RANS simulation, an unsteady RANS (URANS) simulation, and an unsteady Detached Eddy Simulation (DES) were performed. The RANS simulation of the convergent nozzle showed good agreement with the hot-wire velocity and turbulence measurements, though the decay of the potential core was over-predicted. The RANS simulation of the Mach 2.2 nozzle showed poor agreement with the experimental data, and more closely resembled an ideally-expanded jet. The URANS simulation also showed qualitative agreement with the hot-wire data, but predicted a transonic resonance at 1145 Herz. The DES showed good agreement with the hot-wire velocity and turbulence data. The DES also produced a transonic tone at 1135 Herz. The DES solution showed that the destabilization of the shock-induced separation region inside the nozzle produced increased levels of turbulence intensity. This is likely the source of the EBBN.

  14. Transient Side Load Analysis of Out-of-Round Film-Cooled Nozzle Extensions

    Science.gov (United States)

    Wang, Ten-See; Lin, Jeff; Ruf, Joe; Guidos, Mike

    2012-01-01

    There was interest in understanding the impact of out-of-round nozzle extension on the nozzle side load during transient startup operations. The out-of-round nozzle extension could be the result of asymmetric internal stresses, deformation induced by previous tests, and asymmetric loads induced by hardware attached to the nozzle. The objective of this study was therefore to computationally investigate the effect of out-of-round nozzle extension on the nozzle side loads during an engine startup transient. The rocket engine studied encompasses a regeneratively cooled chamber and nozzle, along with a film cooled nozzle extension. The computational methodology is based on an unstructured-grid, pressure-based computational fluid dynamics formulation, and transient inlet boundary flow properties derived from an engine system simulation. Six three-dimensional cases were performed with the out-of-roundness achieved by three different degrees of ovalization, elongated on lateral y and z axes: one slightly out-of-round, one more out-of-round, and one significantly out-of-round. The results show that the separation line jump was the primary source of the peak side loads. Comparing to the peak side load of the perfectly round nozzle, the peak side loads increased for the slightly and more ovalized nozzle extensions, and either increased or decreased for the two significantly ovalized nozzle extensions. A theory based on the counteraction of the flow destabilizing effect of an exacerbated asymmetrical flow caused by a lower degree of ovalization, and the flow stabilizing effect of a more symmetrical flow, created also by ovalization, is presented to explain the observations obtained in this effort.

  15. Geometria de uma obra aberta

    OpenAIRE

    Malheiro, Ana Filipa Candeias de Castro, 1985-

    2013-01-01

    Tese de mestrado, Design de comunicação e novos media, Universidade de Lisboa, Faculdade de Belas Artes, 2013 Based on the proposal for a critical research laboratory in communication design, we propose a theoretical and projectual model acting in the various extensions of design in the context of the network culture. Assuming that the network culture is the exponent of contemporary communication, this paper seeks to examine the extent in which transdisciplinarity contributes to the wideni...

  16. Sludge mobilization with submerged nozzles in horizontal cylindrical tanks

    Energy Technology Data Exchange (ETDEWEB)

    Hylton, T.D.; Cummins, R.L.; Youngblood, E.L.; Perona, J.J.

    1995-10-01

    The Melton Valley Storage Tanks (MVSTs) and the evaporator service tanks at the Oak Ridge National Laboratory (ORNL) are used for the collection and storage of liquid low-level waste (LLLW). Wastes collected in these tanks are typically acidic when generated and are neutralized with sodium hydroxide to protect the tanks from corrosion; however, the high pH of the solution causes the formation of insoluble compounds that precipitate. These precipitates formed a sludge layer approximately 0.6 to 1.2 m (2 to 4 ft) deep in the bottom of the tanks. The sludge in the MVSTs and the evaporator service tanks will eventually need to be removed from the tanks and treated for final disposal or transferred to another storage facility. The primary options for removing the sludge include single-point sluicing, use of a floating pump, robotic sluicing, and submerged-nozzle sluicing. The objectives of this study were to (1) evaluate the feasibility of submerged-nozzle sluicing in horizontal cylindrical tanks and (2) obtain experimental data to validate the TEMPEST (time-dependent, energy, momentun, pressure, equation solution in three dimensions) computer code.

  17. Flow and acoustic features of a supersonic tapered nozzle

    Science.gov (United States)

    Gutmark, E.; Bowman, H. L.; Schadow, K. C.

    1992-05-01

    The acoustic and flow characteristics of a supersonic tapered jet were measured for free and shrouded flow configurations. Measurements were performed for a full range of pressure ratios including over- and underexpanded and design conditions. The supersonic tapered jet is issued from a converging-diverging nozzle with a 3∶1 rectangular slotted throat and a conical diverging section leading to a circular exit. The jet was compared to circular and rectangular supersonic jets operating at identical conditions. The distinct feature of the jet is the absence of screech tones in the entire range of operation. Its near-field pressure fluctuations have a wide band spectrum in the entire range of measurements, for Mach numbers of 1 to 2.5, for over- and underexpanded conditions. The free jet's spreading rate is nearly constant and similar to the rectangular jet, and in a shroud, the pressure drop it is inducing is linearly proportional to the primary jet Mach number. This behavior persisted in high adverse pressure gradients at overexpanded conditions, and with nozzle divergence angles of up to 35°, no inside flow separation was observed.

  18. Plasma-based Control of Supersonic Nozzle Flow

    CERN Document Server

    Gaitonde, Datta V

    2009-01-01

    The flow structure obtained when Localized Arc Filament Plasma Actuators (LAFPA) are employed to control the flow issuing from a perfectly expanded Mach 1.3 nozzle is elucidated by visualizing coherent structures obtained from Implicit Large-Eddy Simulations. The computations reproduce recent experimental observations at the Ohio State University to influence the acoustic and mixing properties of the jet. Eight actuators were placed on a collar around the periphery of the nozzle exit and selectively excited to generate various modes, including first and second mixed (m = +/- 1 and m = +/- 2) and axisymmetric (m = 0). In this fluid dynamics video http://ecommons.library.cornell.edu/bitstream/1813/13723/2/Alljoinedtotalwithmodetextlong2-Datta%20MPEG-1.m1v, http://ecommons.library.cornell.edu/bitstream/1813/13723/3/Alljoinedtotalwithmodetextlong2-Datta%20MPEG-2.m2v}, unsteady and phase-averaged quantities are displayed to aid understanding of the vortex dynamics associated with the m = +/- 1 and m = 0 modes exci...

  19. Noise reduction in supersonic jets by nozzle fluidic inserts

    Science.gov (United States)

    Morris, Philip J.; McLaughlin, Dennis K.; Kuo, Ching-Wen

    2013-08-01

    Professor Philip Doak spent a very productive time as a consultant to the Lockheed-Georgia Company in the early 1970s. The focus of the overall research project was the prediction and reduction of noise from supersonic jets. Now, 40 years on, the present paper describes an innovative methodology and device for the reduction of supersonic jet noise. The goal is the development of a practical active noise reduction technique for low bypass ratio turbofan engines. This method introduces fluidic inserts installed in the divergent wall of a CD nozzle to replace hard-wall corrugation seals, which have been demonstrated to be effective by Seiner (2005) [1]. By altering the configuration and operating conditions of the fluidic inserts, active noise reduction for both mixing and shock noise has been obtained. Substantial noise reductions have been achieved for mixing noise in the maximum noise emission direction and in the forward arc for broadband shock-associated noise. To achieve these reductions (on the order of greater than 4 and 2 dB for the two main components respectively), practically achievable levels of injection mass flow rates have been used. The total injected mass flow rates are less than 4% of the core mass flow rate and the effective operating injection pressure ratio has been maintained at or below the same level as the nozzle pressure ratio of the core flow.

  20. Experimental observations of a complex, supersonic nozzle concept

    Science.gov (United States)

    Magstadt, Andrew; Berry, Matthew; Glauser, Mark; Ruscher, Christopher; Gogineni, Sivaram; Kiel, Barry; Skytop Turbulence Labs, Syracuse University Team; Spectral Energies, LLC. Team; Air Force Research Laboratory Team

    2015-11-01

    A complex nozzle concept, which fuses multiple canonical flows together, has been experimentally investigated via pressure, schlieren and PIV in the anechoic chamber at Syracuse University. Motivated by future engine designs of high-performance aircraft, the rectangular, supersonic jet under investigation has a single plane of symmetry, an additional shear layer (referred to as a wall jet) and an aft deck representative of airframe integration. Operating near a Reynolds number of 3 ×106 , the nozzle architecture creates an intricate flow field comprised of high turbulence levels, shocks, shear & boundary layers, and powerful corner vortices. Current data suggest that the wall jet, which is an order of magnitude less energetic than the core, has significant control authority over the acoustic power through some non-linear process. As sound is a direct product of turbulence, experimental and analytical efforts further explore this interesting phenomenon associated with the turbulent flow. The authors acknowledge the funding source, a SBIR Phase II project with Spectral Energies, LLC. and AFRL turbine engine branch under the direction of Dr. Barry Kiel.

  1. An Investigation of Flow in Nozzle Hole of Dimethyl Ether

    Science.gov (United States)

    Kato, M.; Yokota, T.; Weber, J.; Gill, D.

    2015-12-01

    For over twenty years, DME has shown itself to be a most promising fuel for diesel combustion. DME is produced by simple synthesis of such common sources as coal, natural gas, biomass, and waste feedstock. DME is a flammable, thermally-stable liquid similar to liquefied petroleum gas (LPG) and can be handled like LPG. However, the physical properties of DME such as its low viscosity, lubricity and bulk modulus have negative effects for the fuel injection system, which have both limited the achievable injection pressures to about 500 bar and DME's introduction into the market. To overcome some of these effects, a common rail fuel injection system was adapted to operate with DME and produce injection pressures of up to 1000 bar. To understand the effect of the high injection pressure, tests were carried out using 2D optically accessed nozzles. This allowed the impact of the high vapour pressure of DME on the onset of cavitation in the nozzle hole to be assessed and improve the flow characteristics.

  2. Experimental investigation of shock-cell noise reduction for dual-stream nozzles in simulated flight comprehensive data report. Volume 1: Test nozzles and acoustic data

    Science.gov (United States)

    Yamamoto, K.; Janardan, B. A.; Brausch, J. F.; Hoerst, D. J.; Price, A. O.

    1984-01-01

    Parameters which contribute to supersonic jet shock noise were investigated for the purpose of determining means to reduce such noise generation to acceptable levels. Six dual-stream test nozzles with varying flow passage and plug closure designs were evaluated under simulated flight conditions in an anechoic chamber. All nozzles had combined convergent-divergent or convergent flow passages. Acoustic behavior as a function of nozzle flow passage geometry was measured. The acoustic data consist primarily of 1/3 octave band sound pressure levels and overall sound pressure levels. Detailed schematics and geometric characteristics of the six scale model nozzle configurations and acoustic test point definitions are presented. Tabulation of aerodynamic test conditions and a computer listing of the measured acoustic data are displayed.

  3. Water lance blowers for the cleaning of membrane walls of a 600 MW lignite-fired steam generator; Wasserlanzenblaeser zur Abreinigung von Membranwaenden eines 600-MW-Braunkohledampferzeugers. Betriebserfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, J. [RWE Rheinbraun AG, Kraftwerk Weisweiler (Germany)

    2000-07-01

    The optimal heat absorption in the area of the combustion chamber is not only a prerequisite to attain the designed plant efficiency, but by its direct influence on the combustion chamber temperature also a measure for the further pollution of the subsequent convection heating surfaces. This paper describes the operating experience on cleaning of the combustion chamber water lance blowers and compares the cleaning effect of water lance blowers with the cleaning effect of the so far used water blowers. (orig.) [German] Die optimale Waermeaufnahme des Verdampfers im Bereich des Feuerraumes ist nicht nur eine Voraussetzung fuer das Erreichen des ausgelegten Anlagenwirkungsgrades, sondern durch den direkten Einfluss auf die Feuerraumendtemperatur auch ein Mass fuer die weitere Heizflaechenverschmutzung der nachfolgenden Konvektionsheizflaechen. Im vorliegenden Beitrag werden die Betriebserfahrungen bei der Abreinigung des Feuerraumes mittels Wasserlanzenblaeser dargestellt und die Reinigungswirkung der Wasserlanzenblaeser mit der Reinigungswirkung der bisher eingesetzen Wasserblaeser verglichen. (orig.)

  4. An Evaluation on the Effect of Residual Stress and Phase Transformation Improvement by Welding in Half Nozzle Repair Method of BMI Nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Park, Giyeol; Lee, Sangho; Kim, Taeryong [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2015-10-15

    In this study, it is evaluated that the effect of Pad welding for the Half Nozzle Repair method in the BMI the main instrument of NPP using SYSWELD which is the weld analysis code. BMI (Bottom Mounted Instrumentation) Nozzle is less sensitive to PWSCC generation of Alloy 600 material because the operation temperature is in the relatively low temperature region. But, it is very important to ensure the maintenance of the technical preparation for the damage because Nozzle is installed at reactor bottom head which is not possible to replace. A damage of Reactor Vessel BMI Nozzle under operation was confirmed as No.1 and No.46 Nozzle was observed to find acid precipitate while inspecting the reactor vessel bottom head of STP unit 1 in April 2003. Thus maintenance technology was developed such as Half Nozzle Repair in order to prevent damage of J-Groove welding including BMI Nozzle. In case of J-Groove welding, after cutting J-Groove satisfied the condition required by welding geometry design, new Nozzle of Alloy 690 material is inserted. And then welding applied for welding process parameters is performed when welding procedure applied for Alloy 52 weld filler metal is satisfied. The result of evaluation can be obtained as the following. 1) In order to prevent PWSCC of the BMI nozzle, the Half Nozzle Repair method was performed. As the result, the material Alloy 690 which has the strong corrosion resistance, one of the main factors of PWSCC, was replaced to prevent PWSCC. However, the higher tensile stress, another factor of PWSCC, than yield strength (350MPa) was occurred for Alloy 690 in the inner diameter of the nozzle contacting with the primary water in terms of the Hoop Stress. But compared to the yield strength, it cannot be seen much difference, so the prevention of PWSCC can be estimated. However, additional mechanical surface enhancing procedure such as pinning after welding is required so as to reduce the high tensile stress of the entire welding portion. 2

  5. A Computational Study of a New Dual Throat Fluidic Thrust Vectoring Nozzle Concept

    Science.gov (United States)

    Deere, Karen A.; Berrier, Bobby L.; Flamm, Jeffrey D.; Johnson, Stuart K.

    2005-01-01

    A computational investigation of a two-dimensional nozzle was completed to assess the use of fluidic injection to manipulate flow separation and cause thrust vectoring of the primary jet thrust. The nozzle was designed with a recessed cavity to enhance the throat shifting method of fluidic thrust vectoring. Several design cycles with the structured-grid, computational fluid dynamics code PAB3D and with experiments in the NASA Langley Research Center Jet Exit Test Facility have been completed to guide the nozzle design and analyze performance. This paper presents computational results on potential design improvements for best experimental configuration tested to date. Nozzle design variables included cavity divergence angle, cavity convergence angle and upstream throat height. Pulsed fluidic injection was also investigated for its ability to decrease mass flow requirements. Internal nozzle performance (wind-off conditions) and thrust vector angles were computed for several configurations over a range of nozzle pressure ratios from 2 to 7, with the fluidic injection flow rate equal to 3 percent of the primary flow rate. Computational results indicate that increasing cavity divergence angle beyond 10 is detrimental to thrust vectoring efficiency, while increasing cavity convergence angle from 20 to 30 improves thrust vectoring efficiency at nozzle pressure ratios greater than 2, albeit at the expense of discharge coefficient. Pulsed injection was no more efficient than steady injection for the Dual Throat Nozzle concept.

  6. Nozzle optimization for water jet propulsion with a positive displacement pump

    Science.gov (United States)

    Yang, You-sheng; Xie, Ying-chun; Nie, Song-lin

    2014-06-01

    In the water jet propulsion system with a positive displacement (PD) pump, the nozzle, which converts pressure energy into kinetic energy, is one of the key parts exerting great influence on the reactive thrust and the efficiency of the system due to its high working pressure and easily occurring cavitation characteristics. Based on the previous studies of the energy loss and the pressure distribution of different nozzles, a model of water jet reactive thrust, which fully takes the energy loss and the nozzle parameters into consideration, is developed to optimize the nozzle design. Experiments and simulations are carried out to investigate the reactive thrust and the conversion efficiency of cylindrical nozzles, conical nozzles and optimized nozzles. The results show that the optimized nozzles have the largest reactive thrust and the highest energy conversion efficiency under the same inlet conditions. The related methods and conclusions are extended to the study of other applications of the water jet, such as water jet cutting, water mist fire suppression, water injection molding.

  7. Borehole Miner - Extendible Nozzle Development for Radioactive Waste Dislodging and Retrieval from Underground Storage Tanks

    Energy Technology Data Exchange (ETDEWEB)

    CW Enderlin; DG Alberts; JA Bamberger; M White

    1998-09-25

    This report summarizes development of borehole-miner extendible-nozzle water-jetting technology for dislodging and retrieving salt cake, sludge} and supernate to remediate underground storage tanks full of radioactive waste. The extendible-nozzle development was based on commercial borehole-miner technology.

  8. A refractory steerable nozzle for air and fuel injection in thermal plant boiler combustors

    Energy Technology Data Exchange (ETDEWEB)

    Peschard, J.

    1993-10-01

    The horizontal walls of the tiltable (downwards or upwards) nozzles are corrugated in such a way that they may undergo thermal expansion without cracking. The vertical walls are double-face designed with air flowing inside for cooling. The nozzle is made of refractory steel. Application to air injection with or without pulverized coal or gas, in thermal plants.

  9. Prediction of rarefied micro-nozzle flows using the SPARTA library

    Science.gov (United States)

    Deschenes, Timothy R.; Grot, Jonathan

    2016-11-01

    The accurate numerical prediction of gas flows within micro-nozzles can help evaluate the performance and enable the design of optimal configurations for micro-propulsion systems. Viscous effects within the large boundary layers can have a strong impact on the nozzle performance. Furthermore, the variation in collision length scales from continuum to rarefied preclude the use of continuum-based computational fluid dynamics. In this paper, we describe the application of a massively parallel direct simulation Monte Carlo (DSMC) library to predict the steady-state and transient flow through a micro-nozzle. The nozzle's geometric configuration is described in a highly flexible manner to allow for the modification of the geometry in a systematic fashion. The transient simulation highlights a strong shock structure that forms within the converging portion of the nozzle when the expanded gas interacts with the nozzle walls. This structure has a strong impact on the buildup of the gas in the nozzle and affects the boundary layer thickness beyond the throat in the diverging section of the nozzle. Future work will look to examine the transient thrust and integrate this simulation capability into a web-based rarefied gas dynamics prediction software, which is currently under development.

  10. Measurement and classification methods using the ASAE S572-1 reference nozzles

    Science.gov (United States)

    An increasing number of spray nozzle and agrochemical manufacturers are incorporating droplet size measurements into both research and development with each laboratory invariably having their own sampling setup and procedures, particularly with regard to both measurement distance from the nozzle and...

  11. Nozzle Optimization for Water Jet Propulsion with A Positive Displacement Pump

    Institute of Scientific and Technical Information of China (English)

    杨友胜; 谢迎春; 聂松林

    2014-01-01

    In the water jet propulsion system with a positive displacement (PD) pump, the nozzle, which converts pressure energy into kinetic energy, is one of the key parts exerting great influence on the reactive thrust and the efficiency of the system due to its high working pressure and easily occurring cavitation characteristics. Based on the previous studies of the energy loss and the pressure distribution of different nozzles, a model of water jet reactive thrust, which fully takes the energy loss and the nozzle parameters into consideration, is developed to optimize the nozzle design. Experiments and simulations are carried out to investigate the reactive thrust and the conversion efficiency of cylindrical nozzles, conical nozzles and optimized nozzles. The results show that the optimized nozzles have the largest reactive thrust and the highest energy conversion efficiency under the same inlet conditions. The related methods and conclusions are extended to the study of other applications of the water jet, such as water jet cutting, water mist fire suppression, water injection molding.

  12. Hybrid two fuel system nozzle with a bypass connecting the two fuel systems

    Science.gov (United States)

    Varatharajan, Balachandar [Cincinnati, OH; Ziminsky, Willy Steve [Simpsonville, SC; Yilmaz, Ertan [Albany, NY; Lacy, Benjamin [Greer, SC; Zuo, Baifang [Simpsonville, SC; York, William David [Greer, SC

    2012-05-29

    A hybrid fuel combustion nozzle for use with natural gas, syngas, or other types of fuels. The hybrid fuel combustion nozzle may include a natural gas system with a number of swozzle vanes and a syngas system with a number of co-annular fuel tubes.

  13. Selection of optimum blowers is higly important for energy conservation in ventilation and air conditioning engineering: High-performance radial blowers without a housing; Auswahl des optimalen Ventilators fuer Energieeinsparung in der Luft- und Klimatechnik von grosser Bedeutung: Hochleistungs-Radialventilatoren ohne Gehaeuse

    Energy Technology Data Exchange (ETDEWEB)

    Lexis, J. [Ingenieurbuero Beratung und Planung Luft- und Klimatechnik, Feucht bei Nuernberg (Germany)

    1998-12-01

    There isn`t another component in ventilation and air-conditioning whose choice can result in as much energy conservation as the choice of the optimum blower. Awareness of this fact is increasing. (orig.) [Deutsch] Mit keiner anderen Komponente in der Luft- und Klimatechnik kann so viel Energie gespart werden wie mit der Auswahl des optimalen Ventilators. Deshalb wird der Auswahl des Ventilators immer mehr Aufmerksamkeit geschenkt. (orig.)

  14. Experimental Study on Shock Wave Structures in Constant-area Passage of Cold Spray Nozzle

    Institute of Scientific and Technical Information of China (English)

    Hiroshi KATANODA; Takeshi MATSUOKA; Kazuyasu MATSUO

    2007-01-01

    Cold spray is a technique to make a coating on a wide variety of mechanical or electric parts by spraying solid particles accelerated through a high-speed gas flow in a converging-diverging nozzle. In this study, pseudo-shock waves in a modeled cold spray nozzle as well as high-speed gas jets are visualized by schlieren technique. The schlieren photographs reveals the supersonic flow with shock train in the nozzle. Static pressure along the barrel wall is also measured. The location of the head of pseudo-shock wave and its pressure distribution along the nozzle wall are analytically explained by using a formula of pseudo-shock wave. The analytical results show that the supersonic flow accompanying shock wave in the nozzle should be treated as pseudo-shock wave instead of normal shock wave.

  15. Ultrasonic Phased Array Evaluation of Control Rod Drive Mechanism (CRDM) Nozzle Interference Fit and Weld Region

    Energy Technology Data Exchange (ETDEWEB)

    Cinson, Anthony D.; Crawford, Susan L.; MacFarlan, Paul J.; Mathews, Royce; Hanson, Brady D.; Diaz, Aaron A.

    2011-10-01

    In this investigation, non-destructive and destructive testing were used to evaluate potential boric acid leakage paths around an Alloy 600 CRDM penetration (Nozzle 63) from the North Anna Unit 2 reactor pressure vessel head that was removed from service in 2003. For this investigation, Nozzle 63 was examined using phased array ultrasonic testing. Prior to examining Nozzle 63, a CRDM penetration mockup with known notches and boric acid deposits was used to assess probe sensitivity, resolution and calibration. Following the non-destructive testing of Nozzle 63, the nozzle was destructively examined to visually assess the leak paths. These destructive and nondestructive results are compared and results are presented. The results of this investigation may be used by NRC to evaluate licensees’ volumetric leak path assessment methodologies and to support regulatory inspection requirements.

  16. Gas Nozzle Effect on the Deposition of Polysilicon by Monosilane Siemens Reactor

    Directory of Open Access Journals (Sweden)

    Seung Oh Kang

    2012-01-01

    Full Text Available Deposition of polysilicon (poly-Si was tried to increase productivity of poly-Si by using two different types of gas nozzle in a monosilane Bell-jar Siemens (MS-Siemens reactor. In a mass production of poly-Si, deposition rate and energy consumption are very important factors because they are main performance indicators of Siemens reactor and they are directly related with the production cost of poly-Si. Type A and B nozzles were used for investigating gas nozzle effect on the deposition of poly-Si in a MS-Siemens reactor. Nozzle design was analyzed by computation cluid dynamics (CFD. Deposition rate and energy consumption of poly-Si were increased when the type B nozzle was used. The highest deposition rate was 1 mm/h, and the lowest energy consumption was 72 kWh⋅kg-1 in this study.

  17. Thrust distribution for attitude control in a variable thrust propulsion system with four ACS nozzles

    Science.gov (United States)

    Lim, Yeerang; Lee, Wonsuk; Bang, Hyochoong; Lee, Hosung

    2017-04-01

    A thrust distribution approach is proposed in this paper for a variable thrust solid propulsion system with an attitude control system (ACS) that uses a reduced number of nozzles for a three-axis attitude maneuver. Although a conventional variable thrust solid propulsion system needs six ACS nozzles, this paper proposes a thrust system with four ACS nozzles to reduce the complexity and mass of the system. The performance of the new system was analyzed with numerical simulations, and the results show that the performance of the system with four ACS nozzles was similar to the original system while the mass of the whole system was simultaneously reduced. Moreover, a feasibility analysis was performed to determine whether a thrust system with three ACS nozzles is possible.

  18. Controllable deposition distance of aligned pattern via dual-nozzle near-field electrospinning

    Science.gov (United States)

    Wang, Zhifeng; Chen, Xindu; Zeng, Jun; Liang, Feng; Wu, Peixuan; Wang, Han

    2017-03-01

    For large area micro/nano pattern printing, multi-nozzle electrohydrodynamic (EHD) printing setup is an efficient method to boost productivity in near-field electrospinning (NFES) process. And controlling EHD multi-jet accurate deposition under the interaction of nozzles and other parameters are crucial concerns during the process. The influence and sensitivity of various parameters such as the needle length, needle spacing, electrode-to-collector distance, voltage etc. on the direct-write patterning performance was investigated by orthogonal experiments with dual-nozzle NFES setup, and then the deposition distance estimated based on a novel model was compared with measurement results and proven. More controllable deposition distance and much denser of aligned naofiber can be achieved by rotating the dual-nozzle setup. This study can be greatly contributed to estimate the deposition distance and helpful to guide the multi-nozzle NFES process to accurate direct-write pattern in manufacturing process in future.

  19. Computational Fluid Dynamics Modeling of a Supersonic Nozzle and Integration into a Variable Cycle Engine Model

    Science.gov (United States)

    Connolly, Joseph W.; Friedlander, David; Kopasakis, George

    2015-01-01

    This paper covers the development of an integrated nonlinear dynamic simulation for a variable cycle turbofan engine and nozzle that can be integrated with an overall vehicle Aero-Propulso-Servo-Elastic (APSE) model. A previously developed variable cycle turbofan engine model is used for this study and is enhanced here to include variable guide vanes allowing for operation across the supersonic flight regime. The primary focus of this study is to improve the fidelity of the model's thrust response by replacing the simple choked flow equation convergent-divergent nozzle model with a MacCormack method based quasi-1D model. The dynamic response of the nozzle model using the MacCormack method is verified by comparing it against a model of the nozzle using the conservation element/solution element method. A methodology is also presented for the integration of the MacCormack nozzle model with the variable cycle engine.

  20. Design and testing of low-divergence elliptical-jet nozzles

    Energy Technology Data Exchange (ETDEWEB)

    Rouly, Etienne; Warkentin, Andrew; Bauer, Robert [Dalhousie University, Halifax (China)

    2015-05-15

    A novel approach was developed to design and fabricate nozzles to produce high-pressure low-divergence fluid jets. Rapid-prototype fabrication allowed for myriad experiments investigating effects of different geometric characteristics of nozzle internal geometry on jet divergence angle and fluid distribution. Nozzle apertures were elliptical in shape with aspect ratios between 1.00 and 2.45. The resulting nozzle designs were tested and the lowest elliptical jet divergence angle was 0.4 degrees. Nozzle pressures and flowrates ranged from 0.32 to 4.45 MPa and 13.6 to 37.9 LPM, respectively. CimCool CimTech 310 machining fluid was used in all experiments at a Brix concentration of 6.6 percent.

  1. Turbulent vortex-flow and dynamic pressure oscillations in regenerative blowers; Turbulente Wirbelstroemung und dynamische Druckschwankungen in Seitenkanalmaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Surek, D. [Fachbereich Maschinenbau, Fachhochschule Merseburg (Germany)

    1997-05-01

    Regenerative blowers with high pressure coefficients have high dissipation losses in the side channel and on the breaker. These losses can be in the same magnitude as the polytropic specific head. The cause of the high specific dissipation energy is the turbulent vortex flow in the side channel, which is released by the high numbers of blades and restrict the polytropic efficiency by {eta}=0.46 to 0.50. The enforced turbulent vortex-flow is the reason for the high head coefficients of regenerative blowers. In the side channel, pressure pulsations occur with pressure amplitudes of high frequency up to 40 kHz. These dynamic pressure oscillations are the result of the turbulent vortex-flow. They are indicated from the edge of the impeller blades and the impeller flow in the side channel. For instance, for one rotation of the impeller t=0.02 s and the time between two blades t=0.35 ms. The analysis of the dynamic pressure shows a distribution of the amplitudes over a wide area up to 10 kHz and higher. The dominant amplitudes are the amplitude of blade rotation frequency. The forced turbulent vortex-flow causes a high turbulent vortex-viscosity in the flow and releases a pulse-flow transportation in the side channel. This is the reason for the energy transfer and the increase of the specific dissipation energy in the side channel. With knowledge of the specific pulse-flow transportation of the turbulent vortex-flow the connection to the total transmitted enthalpy can be explained. (orig.) [Deutsch] In Seitenkanalmaschinen mit den grossen Druckzahlen treten hohe Dissipationsverluste im Seitenkanal und im Unterbrecher auf, die von der gleichen Groessenordnung sein koennen wie die polytrope spezifische Nutzarbeit. Die Ursache fuer den grossen spezifischen Dissipationsenergieanteil ist in der turbulenten Wirbelstroemung im Seitenkanal zu suchen, die von den Laufradschaufeln hoher Zahl ausgeloest wird und den Wirkungsgrad der Maschinen auf Werte von {eta}=0,46... 0

  2. PIV Measurements of Chevrons on F400-Series Tactical Aircraft Nozzle Model

    Science.gov (United States)

    Bridges, James; Wernet, Mark P.; Frate, Franco C.

    2011-01-01

    Reducing noise of tactical jet aircraft has taken on fresh urgency as core engine technologies allow higher specific-thrust engines and as society become more concerned for the health of its military workforce. Noise reduction on this application has lagged the commercial field as incentives for quieting military aircraft have not been as strong as in their civilian counterparts. And noise reduction strategies employed on civilian engines may not be directly applicable due to the differences in exhaust system architecture and mission. For instance, the noise reduction technology of chevrons, examined in this study, will need to be modified to take into account the special features of tactical aircraft nozzles. In practice, these nozzles have divergent slats that are tied to throttle position, and at take off the jet flow is highly overexpanded as the nozzle is optimized for cruise altitude rather than sea level. In simple oil flow visualization experiments conducted at the onset of the current test program flow barely stays attached at end of nozzle at takeoff conditions. This adds a new twist to the design of chevrons. Upon reaching the nozzle exit the flow shrinks inward radially, meaning that for a chevron to penetrate the flow it must extend much farther away from the baseline nozzle streamline. Another wrinkle is that with a variable divergence angle on the nozzle, the effective penetration will differ with throttle position and altitude. The final note of realism introduced in these experiments was to simulate the manner in which bypass flow is bled into the nozzle wall in real engines to cool the nozzle, which might cause very fat boundary layer at exit. These factors, along with several other issues specific to the application of chevrons to convergent-divergent nozzles have been explored with particle image velocimetry measurements and are presented in this paper.

  3. Computational fluid dynamics based aerodynamic optimization of the wind tunnel primary nozzle

    Science.gov (United States)

    Jan, Kolář; Václav, Dvořák

    2012-06-01

    The aerodynamic shape optimization of the supersonic flat nozzle is the aim of proposed paper. The nozzle discussed, is applied as a primary nozzle of the inlet part of supersonic wind tunnel. Supersonic nozzles of the measure area inlet parts need to guarantee several requirements of flow properties and quality. Mach number and minimal differences between real and required velocity and turbulence profiles at the nozzle exit are the most important parameters to meet. The aerodynamic shape optimization of the flat 2D nozzle in Computational Fluid Dynamics (CFD) is employed to reach as uniform exit velocity profile as possible, with the mean Mach number 1.4. Optimization process does not use any of standard routines of global or local optimum searching. Instead, newly formed routine, which exploits shape-based oriented sequence of nozzles, is used to research within whole discretized parametric space. The movement within optimization process is not driven by gradient or evolutionary too, instead, the Path of Minimal Shape Deformation is followed. Dynamic mesh approach is used to deform the shape and mesh from the actual nozzle to the subsequent one. Dynamic deformation of mesh allows to speed up whole converging process as an initialization of flow at the newly formed mesh is based on afore-computed shape. Shape-based similarity query in field of supersonic nozzles is discussed and applied. Evolutionary technique with genetic algorithm is used to search for minimal deformational path. As a result, the best variant from the set of solved shapes is analyzed at the base of momentum coefficient and desired Mach number at the nozzle exit.

  4. Application of shape-based similarity query for aerodynamic optimization of wind tunnel primary nozzle

    Directory of Open Access Journals (Sweden)

    Kolář Jan

    2012-04-01

    Full Text Available The aerodynamic shape optimization of the supersonic flat nozzle is the aim of proposed paper. The nozzle discussed, is applied as a primary nozzle of the inlet part of supersonic wind tunnel. Supersonic nozzles of the measure area inlet parts need to guarantee several requirements of flow properties and quality. Mach number and minimal differences between real and required velocity and turbulence profiles at the nozzle exit are the most important parameters to meet. The aerodynamic shape optimization of the flat 2D nozzle in CFD is employed to reach as uniform exit velocity profile as possible, with the mean Mach number 1.4. Optimization process does not use any of standard routines of global or local optimum searching. Instead, newly formed routine, which exploits shape-based oriented sequence of nozzles, is used to research within whole discretized parametric space. The movement within optimization process is not driven by gradient or evolutionary too, instead, the Path of Minimal Shape Deformation is followed. Dynamic mesh approach is used to deform the shape and mesh from the actual nozzle to the subsequent one. Dynamic deformation of mesh allows to speed up whole converging process as an initialization of flow at the newly formed mesh is based on afore-computed shape. Shape-based similarity query in field of supersonic nozzles is discussed and applied. Evolutionary technique with genetic algorithm is used to search for minimal deformational path. As a result, the best variant from the set of solved shapes is analyzed at the base of momentum coefficient and desired Mach number at the nozzle exit.

  5. Application of shape-based similarity query for aerodynamic optimization of wind tunnel primary nozzle

    Science.gov (United States)

    Kolář, Jan

    2012-04-01

    The aerodynamic shape optimization of the supersonic flat nozzle is the aim of proposed paper. The nozzle discussed, is applied as a primary nozzle of the inlet part of supersonic wind tunnel. Supersonic nozzles of the measure area inlet parts need to guarantee several requirements of flow properties and quality. Mach number and minimal differences between real and required velocity and turbulence profiles at the nozzle exit are the most important parameters to meet. The aerodynamic shape optimization of the flat 2D nozzle in CFD is employed to reach as uniform exit velocity profile as possible, with the mean Mach number 1.4. Optimization process does not use any of standard routines of global or local optimum searching. Instead, newly formed routine, which exploits shape-based oriented sequence of nozzles, is used to research within whole discretized parametric space. The movement within optimization process is not driven by gradient or evolutionary too, instead, the Path of Minimal Shape Deformation is followed. Dynamic mesh approach is used to deform the shape and mesh from the actual nozzle to the subsequent one. Dynamic deformation of mesh allows to speed up whole converging process as an initialization of flow at the newly formed mesh is based on afore-computed shape. Shape-based similarity query in field of supersonic nozzles is discussed and applied. Evolutionary technique with genetic algorithm is used to search for minimal deformational path. As a result, the best variant from the set of solved shapes is analyzed at the base of momentum coefficient and desired Mach number at the nozzle exit.

  6. Convective blower and radiator in a single unit: Heating and air conditioning; Geblaesekonvektor und Radiator in einem Geraet: Heizen und Klimatisieren

    Energy Technology Data Exchange (ETDEWEB)

    Steenheuer, H. [Ingenieurbuero Dohrmann, Essen (Germany); Schulz, A. [Axair GmbH, Garching-Hochbrueck (Germany)

    2005-03-01

    Auxiliary cooling of a building is often a question of money. There is a trend to dual-function units. With a central units and convective blowers, i.e. a combination of heat exchanger and heating radiator, air conditioning of rooms is possible in all seasons. [German] Haeufig ist die zusaetzliche Kuehlung von Gebaeuden eine Frage des Geldes. Deshalb geht der Trend immer mehr zu Produkten, die beides ermoeglichen. Mit Zentraleinheit und Geblaesekonvektoren - eine Kombination von Waermetauscher und Heizradiator - koennen Raeume ganzjaehrig klimatisiert werden.

  7. 矿井风机温度的实时采集与控制系统%Real-time acquisition and control system of mine air blower temperature

    Institute of Scientific and Technical Information of China (English)

    王利伟; 王大虎; 查小菲

    2011-01-01

    Air blower is one of the most important equipments for the safety in mine production.Based on the working condition of air blower,AT89C52 single chip microcomputer,the labview roller temperature of blower and the design scheme of online monitor and control system of motors' winding temp,hardware and software configuration of the system and each application function module have been introduced in this article.The collection,processing,presentation,record and early warning of data of mine air blowers' signal can be realized through labview the platform.Through a good labview man-machine interface,operators can demonstrate the dynamically-monitored real-time data and the changing state of parameters.This system can be used into the design of digital measure scope owes to its high stability,high precision and accuracy and provides a new intellectualized manner to test the malfunctions of mine air blowers.%防爆通风机是煤矿安全生产的重要设备,针对矿井通风机的工作状态,提出基于AT89C52单片机、LabView的风机轴温、电动机绕组温度的实时监测与控制的设计方案,并给出系统总体结构,系统软硬件结构和各应用功能模块.通过LabView平台,实现对矿井风机信号的数据采集、处理、显示、记录和报警等功能.利用LabView良好的人机交互界面,可方便工作人员实时得到所检测到的实时数据、参数变化状态.该系统稳定可靠、精度高、准确性好,可用于全数字化检测仪的设计中,为风机故障检测提供了一种新的智能化手段.

  8. 鼓风机轴断裂失效分析%Fracture failure analysis of blower shaft

    Institute of Scientific and Technical Information of China (English)

    王若民; 陈国宏; 施鹏; 缪春辉

    2016-01-01

    In order to find out the fracture reason of the imported blower shaft in a thermal power generating unit, methods of macro-observation, chemical composition analysis, metallographic examination, spectrum analysis, mechanical properties test and microhardness test were used to analyze the failure shaft. The results show that the main reason for the high cycle fatigue fracture of the shaft is due to abnormal secondary quenching, which results in the generation of harmful microstructure such as hardy and brittle quenched martensite and massive soft ferrite along the shaft neck.%针对某火力发电机组进口鼓风机主轴断裂问题,采用宏观断口分析、化学成分分析、金相分析、能谱分析、力学性能和显微硬度检测等手段对其断裂原因进行了分析。结果表明:轴断裂的主要原因是由于异常的二次淬火导致轴颈基体表面形成硬而脆的粗大淬火马氏体和软化的块状铁素体等不良组织,降低了轴颈处的抗疲劳性能,运行过程中在高周交变应力作用下发生疲劳断裂。

  9. Reason Analysis on Fracture of a Blower Coupling%风机联轴器断裂原因分析

    Institute of Scientific and Technical Information of China (English)

    张琴; 李锁才; 岳苗; 张蔓

    2012-01-01

    A membrane blower coupling fractured during the trial operation. Means such as macro examination, metallographic examination, chemical compositions analysis, and mechanical properties test were used to analyze fracture reason of the coupling. The results show that overheated microstructure caused by unsuitable heal treatment was the main reason for the frcature, which resulted in poor toughness of the coupling. And the stress wits not released in time by annealing. Finally early brittle fracture of the coupling occurred in service. Aloe, quenching and tempering treatment to the fractured coupling, the impact toughness wits greatly improved, and the comprehensive mechanical properties of the coupling were excellent.%某风机在试运行过程中其膜片联轴器发生断裂失效,采用宏观分析、金相检验、化学成分分析和力学性能测试等方法对联轴器的断裂原因进行了分析。结果表明:该联轴器发生断裂主要是由于联轴器锻造后热处理不当,形成过热组织缺陷,从而导致其韧性极差;另一方面是由于联轴器锻造后未进行退火处理,内应力未及时消除,最终导致其在使用过程中的应力作用下发生早期脆性断裂失效。对断裂的联轴器进行退火+调质处理,可使其韧性大幅度提高,得到优良的综合力学性能。

  10. LIVROS DIDÁTICOS DE MATEMÁTICA: ANÁLISE DOS RECURSOS DIDÁTICOS AUXILIARES PARA A APRENDIZAGEM DE CONCEITOS ELEMENTARES DE GEOMETRIA NÃO EUCLIDIANA

    Directory of Open Access Journals (Sweden)

    Wanderley Pivatto Brum

    2015-01-01

    Full Text Available Apresentamos os resultados de um estudo que objetivou analisar os recursos didáticos presentes em seis livros didáticos de Matemática, em relação ao conteúdo de Geometria não Euclidiana, utilizados por professores do ensino médio de uma escola pública, no ano de 2013, localizada na cidade de Florianópolis, Santa Catarina. O estudo de caráter documental com abordagem qualitativa, buscou primeiramente verificar o número de capítulos destinados ao tema “Geometria não Euclidiana” e, posteriormente, foram analisadas a presença e frequência de recursos didáticos categorizados como: figuras, charges, história em quadrinhos, indicação de sites, leitura adicional, glossário e práticas. Os resultados mostraram que a maioria dos livros analisados apresentaram o recursofiguras como o mais frequente, seguido por textos complementares para leitura adicional. Recursos didáticoscomo charge e indicação de sites foram encontrados em apenas um dos livros. Em geral, os livros analisados reproduzem ainda um modelo memorístico de ensino que não privilegia a contextualização e participação do estudante no processo de aprendizagem.PALAVRAS-CHAVE: livros didáticos; geometria não euclidiana, recursos didáticos; aprendizagem.TEXTBOOKS OF MATHEMATICS: ANALYSIS OF DIDACTIC RESOURCES AUXILIARY BISHOPS FOR THE LEARNING OF ELEMENTARY CONCEPTS OF NON EUCLIDEAN GEOMETRYABSTRACTWe present the results of a study that aimed to analyze the teaching resources present in six textbooks in Mathematics, in relation to the content of Geometry is not Euclidean, used by teachers of secondary education in a public school, in the year 2013, located in the city of Florianopolis, Santa Catarina.The study of character a qualitative nature, sought to first check the number of chapters for the theme "Geometry is not Euclidean" and, subsequently, were analyzed the presence and frequency of didactic resources categorized as: figures, cartoons, history in comics

  11. Desenho e geometria na escola primária: um casamento duradouro que termina com separação litigiosa - Drawing and geometry in elementary school: a long lasting marriage that ends with a contentious divorce

    Directory of Open Access Journals (Sweden)

    Maria Célia Leme da Silva, Brasil

    2014-01-01

    Full Text Available O artigo analisa a trajetória do Desenho e da Geometria na escola de primeiras letras. Como documentos de pesquisa recorreu-se à legislação e a revistas pedagógicas de grande circulação no período analisado. Conclui-se que, no início, houve uma importante ligação entre o Desenho e a Geometria. Isso mudou, na virada do século 19 para o 20, com a separação entre conteúdo e ensino, quando cada um deles passou a ter objetivos diferentes.Palavras-chave: desenho, geometria, grupos escolares. DRAWING AND GEOMETRY IN ELEMENTARY SCHOOL: A LONG LASTING MARRIAGE THAT ENDS WITH A CONTENTIOUS DIVORCEAbstractThe article analyzes the history of Drawing and Geometry at the elementary school. As sources of research, we use legislation and pedagogical journals of wide circulation in the period were analyzed. It is concluded that initially there was an important link between the drawing and geometry. At the turn of the nineteenth and twentieth centuries, this will change with the separation between teaching content. Each of them has different goals now.Key-words: drawing, geometry, elementary education DISEÑO Y LA GEOMETRÍA EN LA ESCUELA PRIMARIA: UN MATRIMONIO DURADERO QUE TERMINE  CON SEPARACIÓN CONTROVERTIDAResumenEl artículo analiza la trayectoria de Diseño y Geometría en la escuela primaria. Como fuentes de la investigación, utilizamos la legislación y las revistas pedagógicas de amplia circulación en el período analizado. Se concluye que en un principio no había un vínculo importante entre el diseño y la geometría. A la vuelta de los siglos 19 y 20, esto va a cambiar con la separación entre el contenido de la enseñanza. Cada uno de ellos tiene diferentes metas ahoraPalabras-clave: diseño, geometría, escuela primaria. LE DESSIN ET LA GEOMETRIE À L'ÉCOLE PRIMAIRE AU BRÉSIL: UN MARIAGE DURABLE QUI TERMINE PAR UN DIVORCE TURBULENTERésuméL'article analyse la trajectoire du dessin et de géométrie à l

  12. Two-fluid spray atomisation and pneumatic nozzles for fluid bed coating/agglomeration purposes: A review

    DEFF Research Database (Denmark)

    Hede, Peter Dybdahl; Bach, Poul; Jensen, Anker Degn

    2008-01-01

    understood. This paper provides a systematic and up-to-date review of two-fluid nozzle designs and principles together with a presentation of nozzle fundamentals introducing basic nozzle theory and thermodynamics. Correlations for the prediction of mean droplet diameters are reviewed, compared...

  13. EXAMPLE OF FLOW MODELLING CHARACTERISTICS IN DIESEL ENGINE NOZZLE

    Directory of Open Access Journals (Sweden)

    Dušan KOLARIČ

    2016-03-01

    Full Text Available Modern transport is still based on vehicles powered by internal combustion engines. Due to stricter ecological requirements, the designers of engines are continually challenged to develop more environmentally friendly engines with the same power and performance. Unfortunately, there are not any significant novelties and innovations available at present which could significantly change the current direction of the development of this type of propulsion machines. That is why the existing ones should be continually developed and improved or optimized their performance. By optimizing, we tend to minimize fuel consumption and lower exhaust emissions in order to meet the norms defined by standards (i.e. Euro standards. Those propulsion engines are actually developed to such extent that our current thinking will not be able to change their basic functionality, but possible opportunities for improvement, especially the improvement of individual components, could be introduced. The latter is possible by computational fluid dynamics (CFD which can relatively quickly and inexpensively produce calculations prior to prototyping and implementation of accurate measurements on the prototype. This is especially useful in early stages of development or at optimization of dimensional small parts of the object where the physical execution of measurements is impossible or very difficult. With advances of computational fluid dynamics, the studies on the nozzles and outlet channel injectors have been relieved. Recently, the observation and better understanding of the flow in nozzles at large pressure and high velocity is recently being possible. This is very important because the injection process, especially the dispersion of jet fuel, is crucial for the combustion process in the cylinder and consequently for the composition of exhaust gases. And finally, the chemical composition of the fuel has a strong impact on the formation of dangerous emissions, too. The

  14. ADDITIONAL STRESS AND FRACTURE MECHANICS ANALYSES OF PRESSURIZED WATER REACTOR PRESSURE VESSEL NOZZLES

    Energy Technology Data Exchange (ETDEWEB)

    Walter, Matthew [Structural Integrity Associates, Inc.; Yin, Shengjun [ORNL; Stevens, Gary [U.S. Nuclear Regulatory Commission; Sommerville, Daniel [Structural Integrity Associates, Inc.; Palm, Nathan [Westinghouse Electric Company, Cranberry Township, PA; Heinecke, Carol [Westinghouse Electric Company, Cranberry Township, PA

    2012-01-01

    In past years, the authors have undertaken various studies of nozzles in both boiling water reactors (BWRs) and pressurized water reactors (PWRs) located in the reactor pressure vessel (RPV) adjacent to the core beltline region. Those studies described stress and fracture mechanics analyses performed to assess various RPV nozzle geometries, which were selected based on their proximity to the core beltline region, i.e., those nozzle configurations that are located close enough to the core region such that they may receive sufficient fluence prior to end-of-life (EOL) to require evaluation of embrittlement as part of the RPV analyses associated with pressure-temperature (P-T) limits. In this paper, additional stress and fracture analyses are summarized that were performed for additional PWR nozzles with the following objectives: To expand the population of PWR nozzle configurations evaluated, which was limited in the previous work to just two nozzles (one inlet and one outlet nozzle). To model and understand differences in stress results obtained for an internal pressure load case using a two-dimensional (2-D) axi-symmetric finite element model (FEM) vs. a three-dimensional (3-D) FEM for these PWR nozzles. In particular, the ovalization (stress concentration) effect of two intersecting cylinders, which is typical of RPV nozzle configurations, was investigated. To investigate the applicability of previously recommended linear elastic fracture mechanics (LEFM) hand solutions for calculating the Mode I stress intensity factor for a postulated nozzle corner crack for pressure loading for these PWR nozzles. These analyses were performed to further expand earlier work completed to support potential revision and refinement of Title 10 to the U.S. Code of Federal Regulations (CFR), Part 50, Appendix G, Fracture Toughness Requirements, and are intended to supplement similar evaluation of nozzles presented at the 2008, 2009, and 2011 Pressure Vessels and Piping (PVP

  15. Computer Graphic Design Using Auto-CAD and Plug Nozzle Research

    Science.gov (United States)

    Rogers, Rayna C.

    2004-01-01

    The purpose of creating computer generated images varies widely. They can be use for computational fluid dynamics (CFD), or as a blueprint for designing parts. The schematic that I will be working on the summer will be used to create nozzles that are a part of a larger system. At this phase in the project, the nozzles needed for the systems have been fabricated. One part of my mission is to create both three dimensional and two dimensional models on Auto-CAD 2002 of the nozzles. The research on plug nozzles will allow me to have a better understanding of how they assist in the thrust need for a missile to take off. NASA and the United States military are working together to develop a new design concept. On most missiles a convergent-divergent nozzle is used to create thrust. However, the two are looking into different concepts for the nozzle. The standard convergent-divergent nozzle forces a mixture of combustible fluids and air through a smaller area in comparison to where the combination was mixed. Once it passes through the smaller area known as A8 it comes out the end of the nozzle which is larger the first or area A9. This creates enough thrust for the mechanism whether it is an F-18 fighter jet or a missile. The A9 section of the convergent-divergent nozzle has a mechanism that controls how large A9 can be. This is needed because the pressure of the air coming out nozzle must be equal to that of the ambient pressure other wise there will be a loss of performance in the machine. The plug nozzle however does not need to have an A9 that can vary. When the air flow comes out it can automatically sense what the ambient pressure is and will adjust accordingly. The objective of this design is to create a plug nozzle that is not as complicated mechanically as it counterpart the convergent-divergent nozzle.

  16. MHD Simulations of the Plasma Flow in the Magnetic Nozzle

    Science.gov (United States)

    Smith, T. E. R.; Keidar, M.; Sankaran, K.; olzin, K. A.

    2013-01-01

    The magnetohydrodynamic (MHD) flow of plasma through a magnetic nozzle is simulated by solving the governing equations for the plasma flow in the presence of an static magnetic field representing the applied nozzle. This work will numerically investigate the flow and behavior of the plasma as the inlet plasma conditions and magnetic nozzle field strength are varied. The MHD simulations are useful for addressing issues such as plasma detachment and to can be used to gain insight into the physical processes present in plasma flows found in thrusters that use magnetic nozzles. In the model, the MHD equations for a plasma, with separate temperatures calculated for the electrons and ions, are integrated over a finite cell volume with flux through each face computed for each of the conserved variables (mass, momentum, magnetic flux, energy) [1]. Stokes theorem is used to convert the area integrals over the faces of each cell into line integrals around the boundaries of each face. The state of the plasma is described using models of the ionization level, ratio of specific heats, thermal conductivity, and plasma resistivity. Anisotropies in current conduction due to Hall effect are included, and the system is closed using a real-gas equation of state to describe the relationship between the plasma density, temperature, and pressure.A separate magnetostatic solver is used to calculate the applied magnetic field, which is assumed constant for these calculations. The total magnetic field is obtained through superposition of the solution for the applied magnetic field and the self-consistently computed induced magnetic fields that arise as the flowing plasma reacts to the presence of the applied field. A solution for the applied magnetic field is represented in Fig. 1 (from Ref. [2]), exhibiting the classic converging-diverging field pattern. Previous research was able to demonstrate effects such as back-emf at a super-Alfvenic flow, which significantly alters the shape of the

  17. Fuel injection nozzle and method of manufacturing the same

    Energy Technology Data Exchange (ETDEWEB)

    Monaghan, James Christopher; Johnson, Thomas Edward; Ostebee, Heath Michael

    2017-02-21

    A fuel injection head for use in a fuel injection nozzle comprises a monolithic body portion comprising an upstream face, an opposite downstream face, and a peripheral wall extending therebetween. A plurality of pre-mix tubes are integrally formed with and extend axially through the body portion. Each of the pre-mix tubes comprises an inlet adjacent the upstream face, an outlet adjacent the downstream face, and a channel extending between the inlet and the outlet. Each pre-mix tube also includes at least one fuel injector that at least partially extends outward from an exterior surface of the pre-mix tube, wherein the fuel injector is integrally formed with the pre-mix tube and is configured to facilitate fuel flow between the body portion and the channel.

  18. Hydraulic Analogy for Isentropic Flow Through a Nozzle

    Directory of Open Access Journals (Sweden)

    J. S. Rao

    1983-04-01

    Full Text Available Modelling aspects of isentropic compressible gas flow using hydraulic analogy are discussed. Subsonic and supersonic flows through a typical nozzle are simulated as free surface incompressible water flow in an equivalent 2-D model on a water table. The results are first compared for the well known classical analogy in order to estimate experimental errors. Correction factors for pressure and temperature, to account for non-ideal compressible gas flow are presented and the results obtained on the water table are modified and compared with gas dynamic solution. Within the experimental errors, it is shown that the hydraulic analogy can be used as an effective tool for the study of two dimensional isentropic flows of gases.

  19. Hydrodynamic Study of a Submerged Entry Nozzle with Flow Modifiers

    Science.gov (United States)

    Real-Ramirez, Cesar Augusto; Miranda-Tello, Raul; Carvajal-Mariscal, Ignacio; Sanchez-Silva, Florencio; Gonzalez-Trejo, Jesus

    2016-12-01

    The fluid flow modifier technology for continuous casting process was evaluated through numerical simulations and physical experiments in this work. In the casting of steel into the mold, the process presents liquid surface instabilities which extend along the primary cooling stage. By the use of trapezoid elements installed on the external walls of the submerged nozzle, it was observed that it is possible to obtain symmetry conditions at the top of the mold and prevent high level fluctuations. The flow modifiers have equidistant holes in the submerged surface to reduce the velocity of the liquid surface by energy and mass transfer between the generated quadrants. A flow modifier drilled with a 25 pct of the submerged surface provides stability in the mold and structural stability of the proposal is guaranteed.

  20. Apparatus for mixing fuel in a gas turbine nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Barker, Carl Robert

    2016-11-22

    A fuel nozzle in a combustion turbine engine that includes: a fuel plenum defined between an circumferentially extending shroud and axially by a forward tube-sheet and an aft tube-sheet; and a mixing-tube that extends across the fuel plenum that defines a passageway connecting an inlet formed through the forward tube-sheet and an outlet formed through the aft tube-sheet, the mixing-tube comprising one or more fuel ports that fluidly communicate with the fuel plenum. The mixing-tube may include grooves on an outer surface, and be attached to the forward tube-sheet by a connection having a fail-safe leakage path.