Download or read book Contribution l tude des coulements turbulents dans une cavit rotor stator written by Roger Debuchy and published by . This book was released on 2016 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Les recherches exposées s’inscrivent dans la thématique des écoulements turbulents confinés dans une cavité délimitée par deux disques parallèles et coaxiaux, dont l’un est en rotation. Le premier chapitre inclut une description des installations expérimentales et des moyens de mesure mis en place pour étudier les effets d’une faible aspiration forcée sur les propriétés de l’écoulement inter-disques, sans et avec échanges de chaleur. Il présente le bilan des principales conclusions tirées de l’analyse des résultats expérimentaux, notamment du point de vue de l’influence des paramètres adimensionnés sur les champs de vitesses et de température, sur les corrélations turbulentes et les pressions pariétales. Ces travaux ouvrent une nouvelle voie de recherche visant à caractériser la sensibilité de l’écoulement aux effets de l’ouverture périphérique de la cavité rotor-stator à l’atmosphère. L’enjeu scientifique consiste à saisir les mécanismes qui régissent l’interaction entre les écoulements interne et externe à la cavité, tout en évitant une étude exhaustive de l’influence des nombreux paramètres géométriques possibles. Les moyens expérimentaux et numériques mis en oeuvre dans cette optique ainsi que les principales conclusions font l’objet du second chapitre. Le troisième chapitre met l’accent sur le développement de modèles théoriques basés sur une approche asymptotique couplée à des hypothèses simples mais réalistes. Il présente une synthèse des différentes solutions analytiques obtenues et des propriétés originales mises en lumière, telles que l’existence de quantités invariantes, que l'analyse seule des résultats expérimentaux et numériques n'aurait pas permis de déceler." [Source : 4ème de couv.]

Download or read book Advances in Turbulence VII written by Uriel Frisch and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 630 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Turbulence VII contains an overview of the state of turbulence research with some bias towards work done in Europe. It represents an almost complete collection of the invited and contributed papers delivered at the Seventh European Turbulence Conference, sponsored by EUROMECH and ERCOFTAC and organized by the Observatoire de la Côte d'Azur. New high-Reynolds number experiments combined with new techniques of imaging, non-intrusive probing, processing and simulation provide high-quality data which put significant constraints on possible theories. For the first time, it has been shown, for a class of passive scalar problems, why dimensional analysis sometimes gives the wrong answers and how anomalous intermittency corrections can be calculated from first principles. The volume is thus geared towards specialists in the area of flow turbulence who could not attend the conference as well as anybody interested in this rapidly moving field.

Download or read book CONTRIBUTION A L ETUDE DES INSTABILITES DES ECOULEMENTS AXISYMETRIQUES EN CAVITE INTER DISQUES DE TYPE ROTOR STATOR written by NATHALIE.. COUSIN-RITTEMARD and published by . This book was released on 1996 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: DANS UNE PREMIERE PARTIE ON ETUDIE D'ABORD LA STRUCTURATION DES SOLUTIONS STATIONNAIRES INTERDISQUES AXISYMETRIQUES DE TYPE ROTOR-STATOR ET ON LES COMPARE AVEC LES ECOULEMENTS DE SIMILITUDE BIEN CONNUS. DANS CE BUT, DES CODES DE CALCUL POUR EVALUER LES SOLUTIONS STATIONNAIRES ET ETUDIER DE STABILITE LINEAIRE ONT ETE DEVELOPPES. ON MONTRE QUE LE NOMBRE DE REYNOLDS BASE SUR L'ENTREFER PERMET UNE BONNE DESCRIPTION DE L'ECOULEMENT ET PILOTE L'EPAISSEUR DES COUCHES LIMITES. ON MET EN EVIDENCE LA ZONE DE VALIDITE DE LA SOLUTION DE SIMILITUDE PRES DE L'AXE, LA ZONE DE RECIRCULATION PRES DE L'ENVELOPPE ET ENTRE LES DEUX, UNE REGION DE PSEUDO-SIMILITUDE OU LES PROFILS DE VITESSE SONT HOMOTHETIQUES. DANS LA DEUXIEME PARTIE ON ETUDIE L'APPARITION DE L'INSTATIONNARITE PAR SIMULATION NUMERIQUE DIRECTE: LES EQUATIONS DE NAVIER-STOKES SONT INTEGREES PAR UN ALGORITHME PSEUDO-SPECTRAL TCHEBYCHEV. ON OBSERVE UNE TRANSITION DIRECTE DE L'ETAT STATIONNAIRE VERS UN ETAT CHAOTIQUE POUR UN ECART RELATIF AU REYNOLDS CRITIQUE DE UN POUR CENT. LA MISE EN EVIDENCE PAR EXPERIMENTATION NUMERIQUE DE LA NATURE CONVECTIVE DE L'INSTABILITE DE LA COUCHE LIMITE DU STATOR SEMBLE EXPLIQUER CE COMPORTEMENT. UN MANQUE DE RESOLUTION SPATIALE PEUT PRODUIRE UN NIVEAU DE BRUIT SUFFISANT POUR DECLENCHER L'INSTABILITE (PRESSENTIE CONVECTIVE) DU STATOR. AINSI, DANS LA TROISIEME PARTIE, L'ETUDE D'UNE CAVITE TORIQUE MET EN EVIDENCE LA RESPONSABILITE DES EFFETS DE COURBURE SUR LA RAIDEUR DE LA SOLUTION. NEANMOINS, LA BIFURCATION DE HOPF RESPONSABLE DE LA TRANSITION VERS DES SOLUTIONS PERIODIQUES PEUT ETRE ET A ETE ISOLEE INDEPENDAMMENT DE LA GRILLE

Download or read book tude exp rimentale de l influence des conditions p riph riques sur un coulement turbulent de type rotor stator written by Emmanuel D'Haudt and published by . This book was released on 2006 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les recherches effectuées sur des écoulements turbulents dans des cavités interdisques ont permis de mettre en évidence l'importance des conditions aux limites. Ce présent travail a pour but de mieux comprendre les phénomènes qui régissent l'apparition de différents types d'écoulements observés dans une cavité rotor-stator non soumise à un flux radial forcé. Dans cette optique, un banc d'essais a été adapté pour étudier plus spécifiquement l'influence de deux paramètres géométriques, l'un lié à une faible différence entre le rayon des disques, l'autre relatif à la présence d'un carter permettant de supprimer l'écoulement produit par la paroi externe du rotor. La base de données constituée à partir de mesures effectuées principalement par anémométrie à fils chauds a été confrontée à des résultats de simulations numériques réalisés à l'aide du code de calcul FLUENT. L'analyse des résultats montre en particulier qu'à la périphérie du système, le fluide éjecté par l'effet centrifuge du rotor est nécessairement compensé par une injection provenant partiellement du fluide au repos situé à l'extérieur à la cavité, près du stator, et de la réintroduction du fluide éjecté par le rotor. La proportion entre ces deux sources, qui dépend étroitement des paramètres géométriques retenus, influe sur le niveau de pré-rotation du fluide en entrée de cavité et conditionne ainsi l'apparition des différents types d'écoulement observés, notamment l'écoulement en bloc de type Batchelor.

Download or read book Advances in Turbulence written by and published by . This book was released on 1998 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book SIMULATIONS NUMERIQUES D ECOULEMENTS TRANSITIONNELS ET TURBULENTS DANS DES CONFIGURATIONS DE TYPE ROTOR STATOR written by REMI.. JACQUES and published by . This book was released on 1997 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: CE TRAVAIL DE THESE PORTE SUR L'ETUDE NUMERIQUE DES ECOULEMENTS TRANSITIONNELS ET TURBULENTS DANS UNE CAVITE CONFINEE FORMEE DE DEUX DISQUES COAXIAUX DONT L'UN EST EN ROTATION UNIFORME AUTOUR DE SON AXE DE REVOLUTION (ROTOR), ET L'AUTRE STATIONNAIRE (STATOR). LES SIMULATIONS NUMERIQUES SONT EFFECTUEES SOUS L'HYPOTHESE D'AXISYMETRIE DE L'ECOULEMENT INSTANTANE. ON UTILISE ALORS UN CODE DE CALCUL PARALLELISE INTEGRANT UNE DECOMPOSITION DE DOMAINE. PLUSIEURS CARACTERISTIQUES DES ECOULEMENTS ENTRE DEUX DISQUES TOURNANTS SONT REPRODUITES : EXISTENCE DE COUCHES LIMITES SUR LES DEUX DISQUES TOURNANTS, SEPAREES PAR UN REGION CENTRALE DE L'ECOULEMENT EN ROTATION MOYENNE UNIFORME, CARACTERE PLUS INSTABLE DE LA COUCHE LIMITE LIEE AU DISQUE FIXE. L'EXISTENCE D'UN REGIME D'ONDES INERTIELLES A EGALEMENT ETE MIS EN EVIDENCE DANS LE CUR DE LA CAVITE LORSQUE L'ECOULEMENT EST TURBULENT DANS LA COUCHE LIMITE LIEE AU DISQUE FIXE. L'ETUDE DES EQUATIONS DE TRANSPORT DES TENSIONS DE REYNOLDS MONTRE QUE LA ROTATION MODIFIE LES DISTRIBUTIONS SPATIALES DE CERTAINS TERMES INTERVENANT DANS LES BILANS ASSOCIES A CES EQUATIONS. ILS METTENT EGALEMENT EN EVIDENCE LES LIMITATIONS DE L'HYPOTHESE D'AXISYMETRIE QUI MODIFIE ALORS DES CARACTERISTIQUES INTRINSEQUES DE LA TURBULENCE. DES SIMULATIONS NUMERIQUES TRIDIMENSIONNELLES AVEC UN CODE DE CALCUL PARALLELISE SONT ALORS EFFECTUEES POUR LE REGIME D'ECOULEMENT LAMINAIRE INSTATIONNAIRE. CES PREMIERES SIMULATIONS ONT MONTRE QUE L'HYPOTHESE D'AXISYMETRIE STABILISAIT L'ECOULEMENT. ENFIN, LES RESULTATS DE SIMULATION NUMERIQUE SONT CONFRONTES A DES RESULTATS FOURNIS PAR UNE MODELISATION DE LA TURBULENCE DE TYPE K - ET DES RESULTATS EXPERIMENTAUX. LES DEUX METHODOLOGIES NUMERIQUES FOURNISSENT DES RESULTATS RELATIVEMENT PROCHES CONCERNANT LES DISTRIBUTIONS DE VITESSE MOYENNE.

Download or read book Etude exp rimentale des coulements turbulents de type rotor stator avec aspiration radiale et transfert thermique written by Marc Djaoui and published by . This book was released on 1998 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Turbulence 7 written by Uriel Frisch and published by Springer Science & Business Media. This book was released on 1998 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: Suitable for specialists in the field of flow turbulence, this volume comprises an almost complete collection of the papers delivered at the June/July 1998 conference. Providing an overview of the state of turbulence research with some bias towards work done in Europe, contributions are organized into the following sections: experiments and experimental techniques; transition and dynamical systems; numerical simulation; high Reynolds numbers and intermittency; industrial applications and modeling; vortex dynamics; astro- geophysical flow and convection; and transport of passive scalars. Lacks a subject index. Annotation copyrighted by Book News, Inc., Portland, OR

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1990 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Flow and Heat Transfer in Rotating disc Systems written by John Michael Owen and published by . This book was released on 1989 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discussing fluid mechanics and heat transfer in rotating-disc systems, this text simplifies and extends existing information to provide a basic understanding of the subject. Physical insight, mathematical models and experimental data are used to explain the flow structure and provide theoretical methods and correlations which will be of use to research workers and designers.

Download or read book Aeronautical Engineering written by and published by . This book was released on 1993 with total page 932 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).

Download or read book Unsteady Aerodynamics Aeroacoustics and Aeroelasticity of Turbomachines written by Kenneth C. Hall and published by Springer Science & Business Media. This book was released on 2006-05-11 with total page 605 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook is a collection of technical papers that were presented at the 10th International Symposium on Unsteady Aerodynamics, Aeroacoustics, and Aeroelasticity of Turbomachines held September 8-11, 2003 at Duke University in Durham, North Carolina. The papers represent the latest in state of the art research in the areas of aeroacoustics, aerothermodynamics, computational methods, experimental testing related to flow instabilities, flutter, forced response, multistage, and rotor-stator effects for turbomachinery.

Download or read book Recent Developments of Electrical Drives written by Slawomir Wiak and published by Springer Science & Business Media. This book was released on 2007-06-08 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents papers covering a wide spectrum of theory and practice, deeply rooted in engineering problems at a high practical and theoretical level. The contents explore theory, control systems and applications, the heart of the matter in electrical drives.

Download or read book Jet Cutting Technology written by A. Lichtarowicz and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 621 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains papers presented at the 11th International Conference on Jet Cutting Technology, held at St. Andrews, Scotland, on 8-10 September 1992. Jetting techniques have been successfully applied for many years in the field of cleaning and descaling. Today, however, jet cutting is used in operations as diverse as removing cancerous growths from the human body, decommissioning sunsea installations and disabling explosive munitions. The diversity is reflected in the papers presented at the conference. The papers were divided into several main sections: jetting basics -- materials; jetting basics -- fluid mechanics; mining and quarrying; civil engineering; new developments; petrochem; cleaning and surface treatment; and manufacturing. The high quality of papers presented at the conference has further reinforced its position as the premier event in the field. The volume will be of interest to researchers, developers and manufacturers of systems, equipment users and contractors.

Download or read book Computational Fluid Dynamics written by Jiri Blazek and published by Elsevier. This book was released on 2005-12-20 with total page 491 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational Fluid Dynamics (CFD) is an important design tool in engineering and also a substantial research tool in various physical sciences as well as in biology. The objective of this book is to provide university students with a solid foundation for understanding the numerical methods employed in today's CFD and to familiarise them with modern CFD codes by hands-on experience. It is also intended for engineers and scientists starting to work in the field of CFD or for those who apply CFD codes. Due to the detailed index, the text can serve as a reference handbook too. Each chapter includes an extensive bibliography, which provides an excellent basis for further studies.

Download or read book Design and Modeling of Mechanical Systems written by Mohamed Haddar and published by Springer Science & Business Media. This book was released on 2013-03-12 with total page 653 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 5th International Congress on Design and Modeling of Mechanical Systems (CMSM) was held in Djerba, Tunisia on March 25-27, 2013 and followed four previous successful editions, which brought together international experts in the fields of design and modeling of mechanical systems, thus contributing to the exchange of information and skills and leading to a considerable progress in research among the participating teams. The fifth edition of the congress (CMSM ́2013), organized by the Unit of Mechanics, Modeling and Manufacturing (U2MP) of the National School of Engineers of Sfax, Tunisia, the Mechanical Engineering Laboratory (MBL) of the National School of Engineers of Monastir, Tunisia and the Mechanics Laboratory of Sousse (LMS) of the National School of Engineers of Sousse, Tunisia, saw a significant increase of the international participation. This edition brought together nearly 300 attendees who exposed their work on the following topics: mechatronics and robotics, dynamics of mechanical systems, fluid structure interaction and vibroacoustics, modeling and analysis of materials and structures, design and manufacturing of mechanical systems. This book is the proceedings of CMSM ́2013 and contains a careful selection of high quality contributions, which were exposed during various sessions of the congress. The original articles presented here provide an overview of recent research advancements accomplished in the field mechanical engineering.

Download or read book OpenFOAM written by J. Miguel Nóbrega and published by Springer. This book was released on 2019-01-24 with total page 527 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains selected papers of the 11th OpenFOAM® Workshop that was held in Guimarães, Portugal, June 26 - 30, 2016. The 11th OpenFOAM® Workshop had more than 140 technical/scientific presentations and 30 courses, and was attended by circa 300 individuals, representing 180 institutions and 30 countries, from all continents. The OpenFOAM® Workshop provided a forum for researchers, industrial users, software developers, consultants and academics working with OpenFOAM® technology. The central part of the Workshop was the two-day conference, where presentations and posters on industrial applications and academic research were shown. OpenFOAM® (Open Source Field Operation and Manipulation) is a free, open source computational toolbox that has a larger user base across most areas of engineering and science, from both commercial and academic organizations. As a technology, OpenFOAM® provides an extensive range of features to solve anything from complex fluid flows involving chemical reactions, turbulence and heat transfer, to solid dynamics and electromagnetics, among several others. Additionally, the OpenFOAM technology offers complete freedom to customize and extend its functionalities.