Download or read book Mod lisation et calcul num rique des collisions de gouttes en coulements laminaires et turbulents written by Franck Pigeonneau and published by . This book was released on 1998 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: CE MEMOIRE A POUR OBJET LE CALCUL DES COLLISIONS DE GOUTTES DANS DIVERS ECOULEMENTS LAMINAIRES ET TURBULENTS. DANS LE CADRE DE L'APPROXIMATION DES EQUATIONS DE STOKES, LES FORCES D'INTERACTIONS HYDRODYNAMIQUES ENTRE DEUX GOUTTES SONT DETERMINEES DE FACON EXACTE AU MOYEN D'UN SYSTEME DE COORDONNEES BISPHERIQUES. CES FORCES PERMETTENT DE CALCULER LES TAUX DE COLLISION POUR DES ECOULEMENTS DE CISAILLEMENT SIMPLE ET D'ELONGATION PURE. LES SECTIONS DE COLLISION SONT OBTENUES PAR TRAJECTOGRAPHIE. LES RESULTATS MONTRENT UN ACCROISSEMENT DE L'EFFICACITE DE COLLISION LORSQUE L'INERTIE DES GOUTTES CROIT. L'EXPRESSION DU TAUX DE COLLISION EN ECOULEMENT TURBULENT EST ANALOGUE A CELLE UTILISEE EN THEORIE CINETIQUE DES GAZ. LA FONCTION DE DISTRIBUTION DE PAIRES DE PARTICULES EST OBTENUE DANS LE CADRE D'UNE TURBULENCE HOMOGENE ET ISOTROPE ET A L'AIDE DE NOTIONS DE PROBABILITES CONDITIONNELLES. LES TAUX DE COLLISION SONT CALCULES SANS ET AVEC LES FORCES DE GRAVITE. L'EVOLUTION GRANULOMETRIQUE D'UN NUAGE DE GOUTTES EST DECRITE A L'AIDE D'UNE EQUATION CINETIQUE DE TYPE SMOLUCHOWSKI. CETTE EQUATION EST RESOLUE AU MOYEN D'UNE METHODE NUMERIQUE ORIGINALE. DEUX CAS SONT TRAITES. POUR DE PETITES GOUTTES EN ECOULEMENT TURBULENT HOMOGENE ET ISOTROPE, L'ELARGISSEMENT DU SPECTRE DE GOUTTES DEMANDE PLUS DE TEMPS SI LES INTERACTIONS HYDRODYNAMIQUES SONT PRISES EN COMPTE. POUR DE GROSSES GOUTTES, COMPTE TENU DE LA GRAVITE, LA FORMATION PAR COLLISIONS DE GOUTTES DE DIAMETRE SUPERIEUR A 200 MICROMETRES DEPEND FORTEMENT DE LA TURBULENCE. LES RESULTATS CORROBORENT LES RELEVES IN SITU DANS DES NUAGES DE TYPE STRATUS.
Download or read book Multiphase Flow Handbook written by Clayton T. Crowe and published by CRC Press. This book was released on 2005-09-19 with total page 1146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Because of the importance of multiphase flows in a wide variety of industries, including power, petroleum, and numerous processing industries, an understanding of the behavior and underlying theoretical concepts of these systems is critical. Contributed by a team of prominent experts led by a specialist with more than thirty years of experience, the Multiphase Flow Handbook provides such an understanding, and much more. It covers all aspects of multiphase flows, from fundamentals to numerical methods and instrumentation. The book begins with an introduction to the fundamentals of particle/fluid/bubble interactions followed by gas/liquid flows and methods for calculating system parameters. It includes up-to-date information on practical industrial applications such as boiling and condensation, fluidized beds, aerosols, separation systems, pollution control, granular and porous media flow, pneumatic and slurry transport, and sprays. Coverage then turns to the most recent information on particle/droplet-fluid interactions, with a chapter devoted to microgravity and microscale flows and another on basic multiphase interactions. Rounding out the presentation, the authors discuss numerical methods, state-of-the art instrumentation, and advanced experimental techniques. Supplying up-to-date, authoritative information on all aspects of multiphase flows along with numerous problems and examples, the Multiphase Flow Handbook is the most complete reference available for understanding the flow of multiphase mixtures.
Download or read book Simulation num rique directe de gouttes et de groupes de gouttes qui s vaporent dans un coulement laminaire ou turbulent written by Romain Alis (docteur en mécanique des fluides).) and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'évaporation du carburant injecté dans une chambre de combustion est un phénomènecrucial dans un foyer aéronautique car elle détermine la quantité de vapeur qui sera ensuite brûléepour fournir de l'énergie au moteur. Cependant, ce phénomène reste mal décrit du fait desdifficultés de mesurer expérimentalement les taux d'évaporation des gouttes appartenant à unbrouillard. D'autre part, les hypothèses des modèles théoriques ne sont toujours pas représentativesdes conditions rencontrées dans les foyers de combustion.La thèse s'inscrit dans une démarche visant à étudier l'évaporation d'un groupe de gouttesdans un écoulement turbulent au moyen de la Simulation Numérique Directe (SND). En effet, lorsde l'évaporation de groupes de gouttes, des effets collectifs peuvent influer sur le taux d'évaporationde chaque goutte ou sur le taux d'évaporation global du nuage de gouttes. L'approche SNDpermet de quantifier précisément ces effets afin d'améliorer les modèles actuels d'évaporation.Dans un premier temps, des algorithmes ont été développés et utilisés dans une configuration1D sphérique pour décrire l'évaporation d'une goutte statique isolée et sans gravité. Puisdans un second temps, l'évaporation d'une goutte a été étudiée dans un écoulement laminaire.Une analyse des échanges de chaleur entre la goutte et le milieu extérieur ainsi que de la force detraînée exercée par l'écoulement laminaire sur la goutte a été effectuée. Dans cette partie, il a étémis en évidence que l'évaporation induit une diminution des échanges thermiques et de la traînée.Il a notamment été observé que dans certains cas de forte évaporation, la traînée de la gouttepeut devenir négative. Cela implique que l'évaporation peut être à l'origine d'un phénomène depropulsion de la goutte. Une analyse théorique permet de lier ce comportement à une asymétriedu débit d'évaporation. Dans un troisième temps, l'influence de la turbulence sur l'évaporationd'une goutte a été étudiée. Pour cela, un générateur de fluctuations turbulentes a été implémentéet des techniques de calculs parallèles ont été introduites pour réduire le temps des calculs. Celaa permis d'analyser les échanges thermiques et le comportement de la traînée d'une goutte eninteraction avec un écoulement turbulent. Il a été montré que ces deux grandeurs ont tendanceà être amplifiées par la turbulence. Enfin, dans un dernier temps, l'évaporation de groupes degouttes a été étudiée. Pour trois groupes de gouttes différents, les déplacements des gouttes ontété analysés avec les échanges de chaleur lorsque ceux-ci sont placés dans un écoulement laminaireou turbulent avec ou sans changement de phase. En présence d'évaporation, il a été mis enévidence que les déplacements sont différents des cas sans évaporation et donc que le changementde phase modifie les effets collectifs. De plus, ces effets de groupes ont aussi été observés sur leséchanges thermiques.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1048 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mod lisation d coulements turbulents d coll s written by Widah Haj-Ibrahim and published by . This book was released on 1989 with total page 219 pages. Available in PDF, EPUB and Kindle. Book excerpt: Le calcul d'un écoulement turbulent en présence d'un décollement nécessite la résolution numérique des équations de Navier-Stokes et la modélisation de la turbulence. Un code de calcul, développé pour des écoulements internes laminaires et basé sur une méthode de marche itérative pour les équations parabolisées, a été modifié pour simuler des écoulements turbulents. Pour cela, les équations de Navier-Stokes complètes ont été considérées. Pour la mise au point du code numérique, des calculs d'écoulements laminaires décollés (bidimensionnel, subsonique, faiblement compressible) ont été effectués. La longueur de décollement calculée en fonction du nombre de Reynolds dans le cas de la marche descendante est en très bon accord avec les mesures expérimentales. Différents modèles de turbulence ont été introduits moyennant quelques précautions pour conserver la stabilité du calcul. Un schéma à deux couches est adopté : un schéma de longueur de mélange dans les régions de paroi et différents systèmes d'équations de transport ailleurs. À partir des résultats obtenus, le modèle à deux équations de transport, une équation pour l'énergie cinétique de turbulence et une équation pour le frottement turbulent, semble être le plus apte à modéliser la turbulence dans le cas de la marche descendante. Une application à des cas d'écoulement turbulent ou un soufflage affecté le décollement derrière la marche, a mis en évidence la capacité du présent code de calcul à traiter des écoulements plus complexes.
Download or read book Multiphase Flow Handbook Second Edition written by Efstathios Michaelides and published by CRC Press. This book was released on 2016-10-26 with total page 1559 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Multiphase Flow Handbook, Second Edition is a thoroughly updated and reorganized revision of the late Clayton Crowe’s work, and provides a detailed look at the basic concepts and the wide range of applications in this important area of thermal/fluids engineering. Revised by the new editors, Efstathios E. (Stathis) Michaelides and John D. Schwarzkopf, the new Second Edition begins with two chapters covering fundamental concepts and methods that pertain to all the types and applications of multiphase flow. The remaining chapters cover the applications and engineering systems that are relevant to all the types of multiphase flow and heat transfer. The twenty-one chapters and several sections of the book include the basic science as well as the contemporary engineering and technological applications of multiphase flow in a comprehensive way that is easy to follow and be understood. The editors created a common set of nomenclature that is used throughout the book, allowing readers to easily compare fundamental theory with currently developing concepts and applications. With contributed chapters from sixty-two leading experts around the world, the Multiphase Flow Handbook, Second Edition is an essential reference for all researchers, academics and engineers working with complex thermal and fluid systems.
Download or read book A Parallel Finite Volume Algorithm for Large eddy Simulation of Turbulent Flows written by Trong T. Bui and published by . This book was released on 1998 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Particulate Two phase Flow written by M. C. Roco and published by Butterworth-Heinemann. This book was released on 1993 with total page 1032 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a collection of 28 contributions on basic phenomena and advanced methods of investigation for particulate two-phase flow. Written by leading scientists in the field, this book covers new measurement methods, experimental results on particulate two-phase flow microstructure at low and large Reynolds numbers, micromechanical, probabilistic, and numerical simulations, as well as production of ultrafine particles via aerosols and colloids for materials with controlled microstructure. Each chapter is focused on the qualitative progress made in the field in the last several years and has an extensive review section and original results. This unique volume assembles information previously found only in journals and specialized publications. It is an invaluable reference for researchers and engineers from academia and industry.
Download or read book Fundamentals of Heat and Mass Transfer written by S. C. Bhatia and published by . This book was released on 2002-02-01 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Slurry Flow written by C A Shook and published by Elsevier. This book was released on 2013-10-22 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: Slurry Flow: Principles and Practice describes the basic concepts and methods for understanding and designing slurry flow systems, in-plan installations, and long-distance transportation systems. The goal of this book is to enable the design or plant engineer to derive the maximum benefit from a limited amount of test data and to generalize operating experience to new situations. Design procedures are described in detail and are accompanied by illustrative examples needed by engineers with little or no previous experience in slurry transport. The technical literature in this field is extensive: this book facilitates its use by surveying current research results and providing explanations of mechanistic flow models. This discussion of background scientific principles helps the practitioner to better interpret test data, select pumps, specify materials of construction, and choose measuring devises for slurry transport systems. The extensive range of topics covered in Slurry Flow: Principles and practice includes slurry rheology, homogeneous and heterogeneous slurry flow principles, wear mechanisms, pumping equipment, instrumentation, and operating aspects.
Download or read book Advances in Hydroinformatics written by Philippe Gourbesville and published by Springer. This book was released on 2015-08-21 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a collection of extended papers based on presentations given during the SIMHYDRO 2014 conference, held in Sophia Antipolis in June 2014. It focuses on the modeling and simulation of fast hydraulic transients, on 3D modeling, and on uncertainties and multiphase flows. The book explores both the limitations and performance of current models and presents the latest developments based on new numerical schemes, high-performance computing, multiphysics and multiscale methods, and better interaction with field or scale model data. It addresses the interests of practitioners, stakeholders, researchers and engineers active in this field.
Download or read book Annular Two Phase Flow written by Geoffrey Hewitt and published by Elsevier. This book was released on 2013-10-22 with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annular Two-Phase Flow presents the wide range of industrial applications of annular two-phase flow regimes. This book discusses the fluid dynamics and heat transfer aspects of the flow pattern. Organized into 12 chapters, this book begins with an overview of the classification of the various types of interface distribution observed in practice. This text then examines the various regimes of two-phase flow with emphasis on the regions of occurrence of the annular flow regime. Other chapters consider the single momentum and energy balances, which illustrate the differences and analogies between single- and two-phase flows. This book discusses as well the simple modes for annular flow with consideration to the calculation of the profile of shear stress in the liquid film. The final chapter deals with the techniques that are developed for the measurement of flow pattern, entrainment, and film thickness. This book is a valuable resource for chemical engineers.
Download or read book Simon Denny written by Simon Denny and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Simon Denny's new body of work for Portikus ranks among the most ambitious the artist has developed to date. Over the period of one year, the artist researched and developed an intricate project that has grown to considerable dimensions -- both physically and in terms of its critical content. For two months, the monumental gallery space is turned into an homage to technology, communication, and the relentless need for innovation. Simon Denny has produced an embracing and multi-faceted installation that functions as a documentary of the South Korean technology giant Samsung and its global success story. The exhibition's title, "New Management", refers to the legendary management philosophy that Lee Kun-hee, Chairman of the Samsung Group, infamously introduced in the early nineties."--Publisher's website.
Download or read book The Heidegger Change written by Catherine Malabou and published by SUNY Press. This book was released on 2011-12-01 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elaborates the author’s conception of plasticity by proposing a new way of thinking through Heidegger’s writings on change.
Download or read book Computational Heat Transfer written by Yogesh Jaluria and published by Routledge. This book was released on 2017-10-19 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new edition updated the material by expanding coverage of certain topics, adding new examples and problems, removing outdated material, and adding a computer disk, which will be included with each book. Professor Jaluria and Torrance have structured a text addressing both finite difference and finite element methods, comparing a number of applicable methods.
Download or read book In the Flow written by Boris Groys and published by Verso Books. This book was released on 2016-02-16 with total page 211 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the early 20th century, art and its institutions came under critique from a new democratic and egalitarian spirit. In an age of secularism and materialism, artworks would be understood as merely things among other things. This meant an attack on the techniques of realism, and the traditional mission of the museum, both designed shield a small class of objects from the entropic fate awaiting everything else-and the development of an approach that Boris Groys calls "direct realism": an art that would not produce objects, but practices that could enter the flow of time to live and die like the rest of us. But for more than a century now, every advance in this direction has been quickly followed by new means of preserving art's distinction. In this major new work, Groys, one of the world's leading art theorists, charts the paradoxes produced by this tension, which continues to structure the production and reception of new art. The internet, the latest medium through which artists have attempted to disavow this special status, inverts the most notorious consequence of early modernist developments. If the techniques of mechanical reproduction gave us objects without aura, digital production generates aura without objects, transforming all its materials into vanishing markers of the transitory present.
Download or read book Wim Delvoye written by Wim Delvoye and published by Rectapublishers. This book was released on 2001 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Borrowing its name from the ancient sewer in Rome, Belgian conceptualist Wim Delvoye's new and improved "Cloaca" is a room-sized shit-making machine whose bowels process two meals a day, serving up a mouthful of complex themes: scatalogy and disgust, high and low culture, man as machine and vice-versa, and the inversion of art semiotics. Many of these same concerns are processed in Delvoye's other work, like the life-sized carved walnut replica of a cement truck, the wood cabinet stocked with 32 circular saw blades painted with scenes in Delft China blue, and a herd of pigs tatooed by Antwerp's finest needle-men. Feces and other anal subjects are parsed in accompanying essays by such luminaries as Milan Kundera, Gerardo Mosquera, Dan Cameron, Georges Bataille and Salvador Dali.
