Download or read book Evaluation de m thodes num riques nouvelles pour les coulements internes turbulents written by Dominique Vatel and published by . This book was released on 1993 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: UNE ETUDE NUMERIQUE ORIGINALE POUR LA SIMULATION D'ECOULEMENTS INTERNES EST PROPOSEE. LE MODELE ETUDIE EST CELUI DES EQUATIONS DE NAVIER-STOKES COUPLEES AVEC UN MODELE DE TURBULENCE A DEUX EQUATIONS K-EPSILON. POUR LE RESOUDRE, NOUS METTONS EN PLACE UNE METHODE DE SPLITTING. CETTE METHODE CONSISTE A DECOUPLER LE SYSTEME INITIAL EN PLUSIEURS SOUS-SYSTEMES MODELISANTS CHACUN UN OU DES PHENOMENES PHYSIQUES PARTICULIERS. CHACUN DE CES SOUS-SYSTEMES FAIT L'OBJET D'UNE ETUDE MONODIMENSIONNELLE. LA RESOLUTION DE L'UN D'ENTRE EUX A CONDUIT A LA CONSTRUCTION D'UN SOLVEUR DE RIEMANN TURBULENT. UNE EXTENSION A LA DIMENSION DEUX D'ESPACE EST ENSUITE PROPOSEE, AINSI QU'UNE VALIDATION DE LA METHODE

Download or read book Simulations des grandes chelles et mod lisations hybrides RANSE LES pour le calcul d coulements turbulents de grande complexit written by Chikhaoui Oussama and published by . This book was released on 2007 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Au cours de ce travail de thèse, on s’intéresse aux simulations des grandes échelles et aux modèlisations hybrides RANSE/LES. Les capacités du solveur ISIS-CFD initialement conçu pour la résolution des équations Navier-Stokes en moyenne de Reynolds, ont été étendues à ces différentes méthodes en intégrant différents modèles de turbulence de façon à envisager un code de calcul complet capable de traiter une large gamme de problèmes complexes de nature académique ou industrielle. Les modèles et les méthodes numériques choisis et implémentés ont été justifiés et validés sur plusieurs cas test académiques et ont fait l’objet de comparaisons concluantes avec d’autres codes de calcul dans les contextes LES et hybrides. Les méthodes hybrides étudiées ont montré une bonne capacité à retrouver les solutions escomptées tout en permettant une grande économie en résolution de maillage. Un critère basé sur l’évaluation du résidu du budget de quantité de mouvement de l’écoulement moyen a également été proposé comme indicateur des erreurs numériques commises dans les simulations LES et hybrides. Finalement, des simulations d’écoulements turbulents complexes utilisant des modélisations hybrides ont été entreprises. L’utilisation des modélisations hybrides pour le calcul de l’écoulement autour d’un modèle simplifié de voiture en dérapage (corps de Willy) permet de reproduire, avec fidélité et à moindre coût, les observations expérimentales d’un écoulement turbulent de grande complexité.

Download or read book CONTRIBUTION AU DEVELOPPEMENT D UNE METHODE NUMERIQUE D ANALYSE DES ECOULEMENTS INSTATIONNAIRES APPLICATIONS AUX TURBOMACHINES written by LAURENT.. SMATI and published by . This book was released on 1997 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: CETTE THESE CONTRIBUE AU DEVELOPPEMENT DE METHODES NUMERIQUES D'ANALYSE D'ECOULEMENTS INSTATIONNAIRES, ET PLUS PARTICULIEREMENT DES INTERACTIONS FLUIDE/STRUCTURE APPARAISSANT DANS LES TURBOMACHINES. L'OUTIL NUMERIQUE A ETE ELABORE AFIN DE CAPTER LES DIFFERENTES ONDES SE PROPAGEANT DANS UN ECOULEMENT FLUIDE, TOUT EN RESPECTANT UNE BONNE PRECISION TEMPORELLE. LA FERMETURE DE LA TURBULENCE A ETE FAITE VIA UN MODELE A DEUX EQUATIONS DE TRANSPORT K-. L'UTILISATION DE PLUSIEURS SCHEMAS NUMERIQUES SPATIAUX ET TEMPORELS A PERMIS DE METTRE EN EXERGUE LEURS QUALITES ET LEURS FAIBLESSES DANS DES CAS STATIONNAIRES ET INSTATIONNAIRES. LA CRITIQUE DES METHODES NUMERIQUES EST INDISPENSABLE A LA REALISATION D'UNE ANALYSE PHYSIQUE PERTINENTE. DES ETUDES D'ECOULEMENTS INSTATIONNAIRES ONT ETE REALISEES POUR MIEUX COMPRENDRE L'ORIGINE DE LA RUPTURE DES AUBES LORS DE COUPLAGE FLUIDE/STRUCTURE DANS UNE TURBOMACHINE, ET PLUS SPECIALEMENT LORS DU FLOTTEMENT TRANSSONIQUE. LA METHODE A ETE APPLIQUEE A L'ANALYSE DE DEUX CONFIGURATIONS REELLES DE FLOTTEMENT. MAIS, EN RAISON DE LA COMPLEXITE DE CES ECOULEMENTS, IL EST DIFFICILE DE TROUVER L'ORIGINE DU FLOTTEMENT. UNE ETUDE PLUS FONDAMENTALE A ETE REALISEE SUR UNE CONFIGURATION SIMPLE, UNE TUYERE TRANSSONIQUE. ELLE A MIS EN EVIDENCE DIFFERENTS PHENOMENES. D'UNE PART, LES ONDES REGRESSIVES SONT AMPLIFIEES LORSQUE LE NOMBRE DE MACH LOCAL TEND VERS L'UNITE. CE PHENOMENE EST APPELE BLOCAGE ACOUSTIQUE. CETTE ACCUMULATION D'ENERGIE EST THEORIQUEMENT INFINIE. DANS LES SIMULATIONS NUMERIQUES NON-VISQUEUSES ET VISQUEUSES EFFECTUEES, ELLE EST FINIE CAR LIMITEE PAR LA DIFFUSION NUMERIQUE ET PHYSIQUE. D'AUTRE PART, L'INTERACTION ONDE DE CHOC/COUCHE LIMITE JOUE UN ROLE ESSENTIEL LORSQUE L'ONDE DE CHOC EST INTENSE. CETTE INTERACTION PRODUIT DES HARMONIQUES EN TEMPS D'ORDRE SUPERIEUR ET UN DEPHASAGE DU MOUVEMENT DE LA COUCHE LIMITE. OR, C'EST LE DEPHASAGE ENTRE L'EXCITATION ET LA REPONSE A CETTE EXCITATION QUI EST A L'ORIGINE DE L'APPARITION DU FLOTTEMENT.

Download or read book EXPERIENCES NUMERIQUES SUR UN ECOULEMENT TURBULENT DECOLLE written by MARC.. LAZAREFF and published by . This book was released on 1980 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: MISE AU POINT D'UNE METHODE DE CALCUL POUR UN ECOULEMENT TURBULENT PRESENTANT UNE ZONE DE RECIRCULATION ETENDUE DANS LE CAS D'UN ECOULEMENT BIDIMENSIONNEL EN MOYENNE. LA CONFIGURATION ETUDIEE EST CELLE DE LA DOUBLE MARCHE (ELARGISSEMENT SYMETRIQUE BRUSQUE D'UN CANAL PLAN). CHOIX DU MODELE DE TURBULENCE DANS LE CADRE DES MODELES A VISCOSITE TURBULENTE. RESOLUTION NUMERIQUE DES EQUATIONS DU MODELE, DISCRETISEES SUR UN MAILLAGE CARTESIEN A PAS VARIABLE. ETUDE DETAILLEE DU CAS D'UN ECOULEMENT DE CANAL ETABLI A NOMBRE DE REYNOLDS FAIBLE OU ELEVE

Download or read book Acoustics Aeroacoustics and Vibrations written by Fabien Anselmet and published by John Wiley & Sons. This book was released on 2016-01-07 with total page 529 pages. Available in PDF, EPUB and Kindle. Book excerpt: This didactic book presents the main elements of acoustics, aeroacoustics and vibrations. Illustrated with numerous concrete examples linked to solid and fluid continua, Acoustics, Aeroacoustics and Vibrations proposes a selection of applications encountered in the three fields, whether in room acoustics, transport, energy production systems or environmental problems. Theoretical approaches enable us to analyze the different processes in play. Typical results, mostly from numerical simulations, are used to illustrate the main phenomena (fluid acoustics, radiation, diffraction, vibroacoustics, etc.).

Download or read book The General Theory of Homogenization written by Luc Tartar and published by Springer Science & Business Media. This book was released on 2009-12-03 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: Homogenization is not about periodicity, or Gamma-convergence, but about understanding which effective equations to use at macroscopic level, knowing which partial differential equations govern mesoscopic levels, without using probabilities (which destroy physical reality); instead, one uses various topologies of weak type, the G-convergence of Sergio Spagnolo, the H-convergence of François Murat and the author, and some responsible for the appearance of nonlocal effects, which many theories in continuum mechanics or physics guessed wrongly. For a better understanding of 20th century science, new mathematical tools must be introduced, like the author’s H-measures, variants by Patrick Gérard, and others yet to be discovered.

Download or read book The Aeronautical Journal written by and published by . This book was released on 1981 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dissertation Abstracts International written by and published by . This book was released on 1998 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Advances in Hydroinformatics written by Philippe Gourbesville and published by Springer. This book was released on 2018-02-26 with total page 1205 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gathers a collection of extended papers based on presentations given during the SimHydro 2017 conference, held in Sophia Antipolis, Nice, France on June 14–16, 2017. It focuses on how to choose the right model in applied hydraulics and considers various aspects, including the modeling and simulation of fast hydraulic transients, 3D modeling, uncertainties and multiphase flows. The book explores both limitations and performance of current models and presents the latest developments in new numerical schemes, high-performance computing, multiphysics and multiscale methods, and better interaction with field or scale model data. It gathers the lastest theoretical and innovative developments in the modeling field and presents some of the most advance applications on various water related topics like uncertainties, flood simulation and complex hydraulic applications. Given its breadth of coverage, it addresses the needs and interests of practitioners, stakeholders, researchers and engineers alike.

Download or read book Basics of Fluid Mechanics and Introduction to Computational Fluid Dynamics written by Titus Petrila and published by Springer Science & Business Media. This book was released on 2006-06-14 with total page 513 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present book – through the topics and the problems approach – aims at filling a gap, a real need in our literature concerning CFD (Computational Fluid Dynamics). Our presentation results from a large documentation and focuses on reviewing the present day most important numerical and computational methods in CFD. Many theoreticians and experts in the field have expressed their - terest in and need for such an enterprise. This was the motivation for carrying out our study and writing this book. It contains an important systematic collection of numerical working instruments in Fluid Dyn- ics. Our current approach to CFD started ten years ago when the Univ- sity of Paris XI suggested a collaboration in the field of spectral methods for fluid dynamics. Soon after – preeminently studying the numerical approaches to Navier–Stokes nonlinearities – we completed a number of research projects which we presented at the most important inter- tional conferences in the field, to gratifying appreciation. An important qualitative step in our work was provided by the dev- opment of a computational basis and by access to a number of expert softwares. This fact allowed us to generate effective working programs for most of the problems and examples presented in the book, an - pect which was not taken into account in most similar studies that have already appeared all over the world.

Download or read book Finite Volumes for Complex Applications IX Methods Theoretical Aspects Examples written by Robert Klöfkorn and published by Springer Nature. This book was released on 2020-06-09 with total page 727 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proceedings of the 9th conference on "Finite Volumes for Complex Applications" (Bergen, June 2020) are structured in two volumes. The first volume collects the focused invited papers, as well as the reviewed contributions from internationally leading researchers in the field of analysis of finite volume and related methods. Topics covered include convergence and stability analysis, as well as investigations of these methods from the point of view of compatibility with physical principles. Altogether, a rather comprehensive overview is given on the state of the art in the field. The properties of the methods considered in the conference give them distinguished advantages for a number of applications. These include fluid dynamics, magnetohydrodynamics, structural analysis, nuclear physics, semiconductor theory, carbon capture utilization and storage, geothermal energy and further topics. The second volume covers reviewed contributions reporting successful applications of finite volume and related methods in these fields. The finite volume method in its various forms is a space discretization technique for partial differential equations based on the fundamental physical principle of conservation. Many finite volume methods preserve further qualitative or asymptotic properties, including maximum principles, dissipativity, monotone decay of free energy, and asymptotic stability, making the finite volume methods compatible discretization methods, which preserve qualitative properties of continuous problems at the discrete level. This structural approach to the discretization of partial differential equations becomes particularly important for multiphysics and multiscale applications. The book is a valuable resource for researchers, PhD and master’s level students in numerical analysis, scientific computing and related fields such as partial differential equations, as well as engineers working in numerical modeling and simulations.

Download or read book Bulletin de l Institut international du froid written by International Institute of Refrigeration and published by . This book was released on 1996 with total page 1068 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bubbly Flows written by Martin Sommerfeld and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book summarises the outcom of a priority research programme: 'Analysis, Modelling and Computation of Multiphase Flows'. The results of 24 individual research projects are presented. The main objective of the research programme was to provide a better understanding of the physical basis for multiphase gas-liquid flows as they are found in numerous chemical and biochemical reactors. The research comprises steady and unsteady multiphase flows in three frequently found reactor configurations, namely bubble columns without interiors, airlift loop reactors, and aerated stirred vessels. For this purpose new and improved measurement techniques were developed. From the resulting knowledge and data, new and refined models for describing the underlying physical processes were developed, which were used for the establishment and improvement of analytic as well as numerical methods for predicting multiphase reactors. Thereby, the development, lay-out and scale-up of such processes should be possible on a more reliable basis.

Download or read book Boundary Layer Theory written by Hermann Schlichting (Deceased) and published by Springer. This book was released on 2016-10-04 with total page 814 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new edition of the near-legendary textbook by Schlichting and revised by Gersten presents a comprehensive overview of boundary-layer theory and its application to all areas of fluid mechanics, with particular emphasis on the flow past bodies (e.g. aircraft aerodynamics). The new edition features an updated reference list and over 100 additional changes throughout the book, reflecting the latest advances on the subject.

Download or read book Secondary Settling Tanks written by G. A. Ekama and published by International Water Assn. This book was released on 1997-01-01 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: The secondary settling tank (SST) plays a major ro

Download or read book Streamflow Measurement written by Reginald W. Herschy and published by CRC Press. This book was released on 2008-06-30 with total page 535 pages. Available in PDF, EPUB and Kindle. Book excerpt: Too little water or too much'? In either case streamflow measurement is crucial. Climate change could significant affect water resources and flood management. Streamflow measurement is necessary for efficient water management.This third edition deals with all the main current methods for measuring the flow in rivers and open channels, in accordanc