Download or read book APPLICATION DE MODELES DANS L ESPACE SPECTRAL A D AUTRES NIVEAUX DE FERMETURE EN TURBULENCE HOMOGENE written by Bertrand Aupoix and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: LES FERMETURES EN DEUX POINTS, TELLES QUE LA FERMETURE EDQNM, PERMETTENT D'EVALUER LES TRANSFERTS ENERGETIQUES ENTRE MODES DE TURBULENCE; ELLES CONSTITUENT UN OUTIL APPROPRIE POUR LA CONSTRUCTION DE MODELES DE SOUS-MAILLE DANS LES SIMULATIONS DES GRANDES ECHELLES. EN TURBULENCE HOMOGENE ISOTROPE, NOUS AVONS D'ABORD PROPOSE DE COUPLER UNE SIMULATION DES GRANDES ECHELLES AVEC UN CALCUL DU SPECTRE D'ENERGIE DES PETITES ECHELLES. UN MODELE SIMPLIFIE, BASE SUR LE CONCEPT DE TRANSFERT NON LOCAL, A ENSUITE ETE DERIVE. LES MODELES CLASSIQUES SONT AINSI RETROUVES, VOIRE AMELIORES. CETTE APPROCHE A ENSUITE ETE ETENDUE AU CAS D'UNE TURBULENCE ISOTROPE SOUMISE A UNE ROTATION EN BLOC, POUR TESTER UN MODELE EDQNM PRENANT EN COMPTE LE BLOCAGE DES TRANSFERTS D'ENERGIE PAR LA ROTATION. L'EMPLOI DE LA FORMULATION NON LOCALE A ENFIN ETE VALIDE DANS LE CAS DE LA TURBULENCE HOMOGENE ANISOTROPE POUR METTRE EN EVIDENCE LE PHENOMENE DE RETOUR D'ANISOTROPIE DES PETITES ECHELLES VERS LES GRANDES ECHELLES. L'APPROCHE SPECTRALE PERMET AUSSI D'AMELIORER LES FERMETURES EN UN POINT. DE NOMBREUSES SIMULATIONS AVEC LE MODELE EDQNM NOUS ONT CONDUIT A UNE CORRECTION DE L'EQUATION POUR LE TAUX DE DISSIPATION PRENANT EN COMPTE LA ROTATION. LES METHODES INTEGRALES SPECTRALES, BASEES SUR DES FORMES DE SPECTRE SIMPLIFIEES, NOUS ONT PERMIS D'AMELIORER L'EQUATION DE TRANSPORT POUR LE TAUX DE DISSIPATION EN FAISANT APPARAITRE DE NOUVEAUX TEMPS CARACTERISTIQUES ET DE METTRE EN EVIDENCE LE ROLE DE DIFFERENTS PHENOMENES DANS LES MODELES MULTI-ECHELLES

Download or read book ETUDE THEORIQUE ET EXPERIMENTALE D UNE TURBULENCE HOMOGENE SOUMISE A DES EFFETS COUPLES DE ROTATION ET DE DEFORMATION PLANE written by JEAN-PIERRE.. BENOIT and published by . This book was released on 1992 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'ETUDE THEORIQUE DES CARACTERISTIQUES ANISOTROPES D'UNE TURBULENCE HOMOGENE SOUMISE A DES GRADIENTS MOYENS PLANS EST ABORDEE DANS L'ESPACE SPECTRAL. DIFFERENTS COUPLAGES DU TAUX DE ROTATION/DEFORMATION SONT EXAMINES DE PART ET D'AUTRE DU CAS CENTRAL DE CISAILLEMENT PUR. LA RESOLUTION DU PROBLEME LINEAIRE EST REALISEE SUR L'EQUATION DU SPECTRE DE LA FLUCTUATION DE VITESSE. LA SOLUTION NUMERIQUE EST DETAILLEE DANS LE CAS DES ECOULEMENTS ELLIPTIQUES AFIN DE FAIRE LE LIEN AVEC LES ETUDES DE STABILITE DE CES ECOULEMENTS PERIODIQUES. L'APPROCHE NON LINEAIRE PORTE SUR L'EQUATION DU TENSEUR SPECTRAL D'ORDRE 2. UNE FERMETURE DU TYPE EDQNM EST UTILISEE POUR DECRIRE L'EVOLUTION DES CORRELATIONS TRIPLES. LE CALCUL DU TERME NON LINEAIRE DE L'EQUATION DE CRAYA EST SIMPLIFIE EN UTILISANT UNE DECOMPOSITION EN HARMONIQUES SPHERIQUES POUR LE TENSEUR D'ORDRE 2. L'ETUDE EXPERIMENTALE, MENEE PARALLELEMENT, FOURNIT LES EVOLUTIONS ANISOTROPES DES TENSIONS DE REYNOLDS POUR LES CAS DE COUPLAGE SUIVANTS: DEFORMATION PURE PLANE, DEFORMATION DOMINANTE, CISAILLEMENT PUR ET ROTATION DOMINANTE. LES RESULTATS LINEAIRES DONNENT LES TENDANCES DE L'ANISOTROPIE. PAR CONTRE, LE CALCUL NON LINEAIRE SE HEURTE A UN PROBLEME DE REALISABILITE DU TENSEUR SPECTRAL. CET ECUEIL TEND A PROUVER QUE LE DEGRE DE TRONCATURE DES SERIES D'HARMONIQUES SPHERIQUES, CHOISI EGAL A 2, POUR UNE SIMPLIFICATION DE LA MODELISATION, EST TROP BAS

Download or read book Etude th orique de la turbulence homog ne soumise des effets de rotation et mod lisation en vue de l implantation au sein d un code r solvant les quations de Navier Strokes written by Jean-Louis Lubrano and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: La rotation a une influence certaine sur la turbulence homogène par le biais des forces de Coriolis. Ces effets, mal pris en compte par les modélisations classiques, nécessitent une approche plus élaborée. Un recours possible est la recherche d'informations dans l'espace spectral où les différents termes de l'équation du tenseur spectral ont une signification physique plus facile à appréhender. Ainsi a-t'il été mis clairement en evidence une partition de l'anisotropie en une composante caractérisant la directivité du champ énergétique et une composante définissant sa polarisation. Cette séparation s'accompagne de comportements différents tant sur les termes linéaires que non linéaires et permet une modélisation en accord avec les phénomènes observés. Une extension à une turbulence homogène soumise à une déformation plus générale a été proposée dans le cadre de ce travail. Malheureusement, les résultats laissent supposer qu'il est nécessaire d'appliquer un développement au second ordre et il a été préféré une modélisation provenant d'une étude américaine de W.C. Reynolds, cette dernière se rattachant a la théorie spectrale. Un modèle construit à partir de ces divers éléments a été implanté au sein d'un code de calcul Navier Stokes sur une configuration de type canal plan avec effets de rotation. Cette étude permet donc d'avoir une base de travail confortable, afin d'obtenir une modélisation future dont les résultats devraient s'avérer probants.

Download or read book Dynamique Non lin aire Et Le Chaos written by and published by . This book was released on 1993 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Dictionary of Building and Civil Engineering written by Don Montague and published by Taylor & Francis. This book was released on 1996 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dual-language dictionary lists over 20,000 specialist terms in both French and English, covering architecture, building, engineering and property terms. It meets the needs of all building professionals working on projects overseas. It has been comprehensively researched and compiled to provide an invaluable reference source in an increasingly European marketplace.

Download or read book The Number System written by H. A. Thurston and published by Courier Corporation. This book was released on 2012-10-23 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores arithmetic's underlying concepts and their logical development, in addition to a detailed, systematic construction of the number systems of rational, real, and complex numbers. 1956 edition.

Download or read book Proceedings of the International Congress of Mathematicians written by S.D. Chatterji and published by Birkhäuser. This book was released on 2012-12-06 with total page 1669 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the first ICM was held in Zürich in 1897, it has become the pinnacle of mathematical gatherings. It aims at giving an overview of the current state of different branches of mathematics and its applications as well as an insight into the treatment of special problems of exceptional importance. The proceedings of the ICMs have provided a rich chronology of mathematical development in all its branches and a unique documentation of contemporary research. They form an indispensable part of every mathematical library. The Proceedings of the International Congress of Mathematicians 1994, held in Zürich from August 3rd to 11th, 1994, are published in two volumes. Volume I contains an account of the organization of the Congress, the list of ordinary members, the reports on the work of the Fields Medalists and the Nevanlinna Prize Winner, the plenary one-hour addresses, and the invited addresses presented at Section Meetings 1 - 6. Volume II contains the invited address for Section Meetings 7 - 19. A complete author index is included in both volumes. '...the content of these impressive two volumes sheds a certain light on the present state of mathematical sciences and anybody doing research in mathematics should look carefully at these Proceedings. For young people beginning research, this is even more important, so these are a must for any serious mathematics library. The graphical presentation is, as always with Birkhäuser, excellent....' (Revue Roumaine de Mathematiques pures et Appliquées)

Download or read book Genmix written by D Brian Spalding and published by Elsevier. This book was released on 2014-05-18 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt: Genmix: A General Computer Program for Two-dimensional Parabolic Phenomena explains a computer program called GENMIX. The main intention of the program is to be used as a tool of instructions. The name of the program is a mixture of two considerations: its generality and its concern for mixing processes. The book aims to help the potential user to understand the physical and mathematical basis of the topic computer program. It is also the aim of the book to make the program applicable to practical problems. The book is arranged in such a way as to parallel a course of lectures and associated computer-workshop sessions wherein the student is allowed to do some elementary computations as soon as he has gained some knowledge of the method. The book contains the mathematical, physical, and computer-coding aspects of the program. Concepts such as the boundary layer, two-dimensional, and steady- flow are defined and discussed in depth. The text will be a useful tool for computer instructors and students.

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 Computational Methods for Fluid Dynamics written by Joel H Ferziger and published by . This book was released on 1996-02-14 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Heat and Mass Transfer in Boundary Layers written by Suhas V. Patankar and published by . This book was released on 1970 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book General Topology written by J. Dixmier and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a course in general topology, intended for students in the first year of the second cycle (in other words, students in their third univer sity year). The course was taught during the first semester of the 1979-80 academic year (three hours a week of lecture, four hours a week of guided work). Topology is the study of the notions of limit and continuity and thus is, in principle, very ancient. However, we shall limit ourselves to the origins of the theory since the nineteenth century. One of the sources of topology is the effort to clarify the theory of real-valued functions of a real variable: uniform continuity, uniform convergence, equicontinuity, Bolzano-Weierstrass theorem (this work is historically inseparable from the attempts to define with precision what the real numbers are). Cauchy was one of the pioneers in this direction, but the errors that slip into his work prove how hard it was to isolate the right concepts. Cantor came along a bit later; his researches into trigonometric series led him to study in detail sets of points of R (whence the concepts of open set and closed set in R, which in his work are intermingled with much subtler concepts). The foregoing alone does not justify the very general framework in which this course is set. The fact is that the concepts mentioned above have shown themselves to be useful for objects other than the real numbers.

Download or read book Underground Disposal of Radioactive Wastes written by International Atomic Energy Agency and published by . This book was released on 1981 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Introduction to Differential Manifolds written by Jacques Lafontaine and published by Springer. This book was released on 2015-07-29 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an introduction to differential manifolds. It gives solid preliminaries for more advanced topics: Riemannian manifolds, differential topology, Lie theory. It presupposes little background: the reader is only expected to master basic differential calculus, and a little point-set topology. The book covers the main topics of differential geometry: manifolds, tangent space, vector fields, differential forms, Lie groups, and a few more sophisticated topics such as de Rham cohomology, degree theory and the Gauss-Bonnet theorem for surfaces. Its ambition is to give solid foundations. In particular, the introduction of “abstract” notions such as manifolds or differential forms is motivated via questions and examples from mathematics or theoretical physics. More than 150 exercises, some of them easy and classical, some others more sophisticated, will help the beginner as well as the more expert reader. Solutions are provided for most of them. The book should be of interest to various readers: undergraduate and graduate students for a first contact to differential manifolds, mathematicians from other fields and physicists who wish to acquire some feeling about this beautiful theory. The original French text Introduction aux variétés différentielles has been a best-seller in its category in France for many years. Jacques Lafontaine was successively assistant Professor at Paris Diderot University and Professor at the University of Montpellier, where he is presently emeritus. His main research interests are Riemannian and pseudo-Riemannian geometry, including some aspects of mathematical relativity. Besides his personal research articles, he was involved in several textbooks and research monographs.

Download or read book The Large Sieve written by Klaus Friedrich Roth and published by . This book was released on 1969 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: