Download or read book M thodologie pour la simulation num rique des vibrations induites par coulements dans les faisceaux de tubes written by Zaky Bendjeddou and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cette thèse présente une méthodologie pour la simulation numérique des vibrations induites par les écoulements dans les faisceaux de tubes. Dans un premier temps une validation des efforts fluides exercés sur un tube fixe dans une configuration de canal ou de faisceaux de tubes en écoulements laminaires et turbulents est présentée. Dans un deuxième temps la fonnulation Arbitraire Lagrange Euler (ALE) des équations de Navier-Stokes permettant la gestion de frontières mobiles est décrite, en particulier le choix et le calcul de la vitesse de maillage. Ensuite les schémas de couplage utilisés pour la modélisation des couplages fluide-structure sont décrits et les propriétés des schémas explicites et implicites sont étudiés. Une première validation des coefficients de couplage fluide structure sur des configurations avec cylindres concentriques et de faisceaux de tubes est présentée. Enfin une première simulation numérique des couplages fluide-élastiques en faisceaux de tubes en présence d'écoulements transverses laminaires est réalisée avec identification numérique de premiers paramètres fluide-élastiques et mise en évidence de départs en instabilité fluide-élastique.

Download or read book M thode d homog n isation pour la vibration de faisceaux de tubes en pr sence de fluide written by Quentin Desbonnets and published by . This book was released on 2012 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dans l'industrie nucléaire on rencontre fréquemment des problématiques mettant en jeu des faisceaux de tubes immergés dans un fluide. Les problématiques de sureté nucléaire font que les comportements des ces systèmes sous sollicitation sismique doivent être maîtrisés. Les systèmes de type faisceau de tubes en présence de fluide voient leur comportement vibratoire modifié. Par leurs géométries complexes, la simulation numérique de ces systèmes nécessite des temps de calculs extrêmement importants. Afin de surmonter ce problème, des modèles homogénéisés ont été mis en place. Ces modèles sont basés sur les équations d'Euler linéarisées pour le fluide. Cependant ils ne prennent en compte que les effets inertiels, et supposent des très petits déplacements de structures. Pour y remédier, on développe donc de nouveaux modèles à partir des équations de Navier-Stokes. Cette thèse porte sur la mise en place d'un modèle homogénéisé de la vibration d'un faisceau de tubes immergé dans du fluide. Le fluide est visqueux et les mouvements de structure sont importants. À partir d'une méthode de prise de moyenne, on établit un modèle homogénéisé se basant sur la notion de vitesse de Darcy. Le modèle obtenu dépend de deux paramètres : Le coefficient de masse ajoutée Cm et le coefficient dissipatif Cd. Ces coefficients représentent les effets inertiels et dissipatifs du fluide sans avoir à décrire explicitement les écoulements à l'échelle locale.

Download or read book CONTRIBUTION A L ETUDE DES VIBRATIONS DE FAISCEAUX DE TUBES EN ECOULEMENT TRANSVERSAL written by JOSE.. ANTUNES and published by . This book was released on 1986 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: ANALYSES DYNAMIQUES NON-LINEAIRES POUR LA PREDICTION DES RISQUES VIBRATOIRES ET D'USURE DES FAISCEAUX DE TUBES, ET TENANT COMPTE DU FAIT QUE LES APPUIS PRESENTENT DES VARIATIONS PAR RAPPORT AUX CONDITIONS NOMINALES. METHODOLOGIE PERMETTANT L'ANALYSE GLOBALE DU COMPORTEMENT DYNAMIQUE NON-LINEAIRE DES TUBES. SIMULATION DES SOURCES D'EXCITATION PAR L'ECOULEMENT. APPLICATION AUX CENTRALES NUCLEAIRES

Download or read book CONTRIBUTION A L ETUDE DES VIBRATIONS ET DE L USURE DES FAISCEAUX DE TUBES EN ECOULEMENT TRANSVERSAL written by BERTRAND.. BEAUFILS and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: DANS CE MEMOIRE, ON ETUDIE LES VIBRATIONS ET L'USURE DES TUBES D'ECHANGEURS DE CHALEUR IMPACTANT SUR LEURS SUPPORTS A JEUX, SOUS EXCITATION PAR LES ECOULEMENTS TRANSVERSES. ON S'INTERESSE D'UNE PART A LA MODELISATION DES FORCES EXERCEES PAR L'ECOULEMENT SUR LES TUBES: 1) EXCITATION PAR LA TURBULENCE; 2) FORCES FLUIDE-ELASTIQUES. D'AUTRE PART, ON ETUDIE LE FROTTEMENT SEC QUI INTERVIENT DANS LES IMPACTS DES TUBES SUR LEURS SUPPORTS. LES MODELISATIONS QUI DECOULENT DE CES ETUDES SONT INTRODUITES DANS UN CODE DE CALCUL A PORTEE INDUSTRIELLE. DIFFERENTES ETUDES PARAMETRIQUES SONT PRESENTEES, AINSI QU'UNE VALIDATION DE LA METHODOLOGIE PAR L'EXPERIENCE

Download or read book In Vessel Melt Retention and Ex Vessel Corium Cooling IAEA Tecdoc No 1906 written by International Atomic Energy Agency and published by International Atomic Energy Agency. This book was released on 2020-08-06 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication results from a technical meeting on phenomenology and technologies relevant to in-vessel melt retention (IVMR) and ex-vessel corium cooling (EVCC). The purpose of the publication is to capture the state of knowledge, at the time of that meeting, related to phenomenology and technologies as well as the challenges and pending issues relevant to IVMR and EVCC for water cooled reactors by summarizing the information provided by the meeting participants in a form useful to practitioners in Member States.

Download or read book Flexoelectricity in Liquid Crystals written by Agnes Buka and published by World Scientific. This book was released on 2013 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book intends to give a state-of-the-art overview of flexoelectricity, a linear physical coupling between mechanical (orientational) deformations and electric polarization, which is specific to systems with orientational order, such as liquid crystals. Chapters written by experts in the field shed light on theoretical as well as experimental aspects of research carried out since the discovery of flexoelectricity. Besides a common macroscopic (continuum) description the microscopic theory of flexoelectricity is also addressed. Electro-optic effects due to or modified by flexoelectricity as well as various (direct and indirect) measurement methods are discussed. Special emphasis is given to the role of flexoelectricity in pattern-forming instabilities. While the main focus of the book lies in flexoelectricity in nematic liquid crystals, peculiarities of other mesophases (bent-core systems, cholesterics, and smectics) are also reviewed. Flexoelectricity has relevance to biological (living) systems and can also offer possibilities for technical applications. The basics of these two interdisciplinary fields are also summarized.

Download or read book Handbook of Nonlinear Partial Differential Equations written by Andrei D. Polyanin and published by CRC Press. This book was released on 2004-06-02 with total page 835 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Handbook of Nonlinear Partial Differential Equations is the latest in a series of acclaimed handbooks by these authors and presents exact solutions of more than 1600 nonlinear equations encountered in science and engineering--many more than any other book available. The equations include those of parabolic, hyperbolic, elliptic and other types, and the authors pay special attention to equations of general form that involve arbitrary functions. A supplement at the end of the book discusses the classical and new methods for constructing exact solutions to nonlinear equations. To accommodate different mathematical backgrounds, the authors avoid wherever possible the use of special terminology, outline some of the methods in a schematic, simplified manner, and arrange the equations in increasing order of complexity. Highlights of the Handbook:

Download or read book Introduction to Nonsmooth Optimization written by Adil Bagirov and published by Springer. This book was released on 2014-08-12 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the first easy-to-read text on nonsmooth optimization (NSO, not necessarily differentiable optimization). Solving these kinds of problems plays a critical role in many industrial applications and real-world modeling systems, for example in the context of image denoising, optimal control, neural network training, data mining, economics and computational chemistry and physics. The book covers both the theory and the numerical methods used in NSO and provide an overview of different problems arising in the field. It is organized into three parts: 1. convex and nonconvex analysis and the theory of NSO; 2. test problems and practical applications; 3. a guide to NSO software. The book is ideal for anyone teaching or attending NSO courses. As an accessible introduction to the field, it is also well suited as an independent learning guide for practitioners already familiar with the basics of optimization.

Download or read book Mathematics of the Decision Sciences written by George Bernard Dantzig and published by American Mathematical Soc.. This book was released on 1968-12-31 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nonsmooth Optimization written by Claude Lemarechal and published by Elsevier. This book was released on 2014-05-19 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nonsmooth Optimization contains the proceedings of a workshop on non-smooth optimization (NSO) held from March 28 to April 8,1977 in Austria under the auspices of the International Institute for Applied Systems Analysis. The papers explore the techniques and theory of NSO and cover topics ranging from systems of inequalities to smooth approximation of non-smooth functions, as well as quadratic programming and line searches. Comprised of nine chapters, this volume begins with a survey of Soviet research on subgradient optimization carried out since 1962, followed by a discussion on rates of convergence in subgradient optimization. The reader is then introduced to the method of subgradient optimization in an abstract setting and the minimal hypotheses required to ensure convergence; NSO and nonlinear programming; and bundle methods in NSO. A feasible descent algorithm for linearly constrained least squares problems is described. The book also considers sufficient minimization of piecewise-linear univariate functions before concluding with a description of the method of parametric decomposition in mathematical programming. This monograph will be of interest to mathematicians and mathematics students.

Download or read book Nonlinear Optical Materials written by Jerome V. Moloney and published by Springer Science & Business Media. This book was released on 1998-08-13 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mathematical methods play a significant role in the rapidly growing field of nonlinear optical materials. This volume discusses a number of successful or promising contributions. The overall theme of this volume is twofold: (1) the challenges faced in computing and optimizing nonlinear optical material properties; and (2) the exploitation of these properties in important areas of application. These include the design of optical amplifiers and lasers, as well as novel optical switches. Research topics in this volume include how to exploit the magnetooptic effect, how to work with the nonlinear optical response of materials, how to predict laser-induced breakdown in efficient optical devices, and how to handle electron cloud distortion in femtosecond processes.

Download or read book Fixed Point Theorems with Applications to Economics and Game Theory written by Kim C. Border and published by Cambridge University Press. This book was released on 1985 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores fixed point theorems and its uses in economics, co-operative and noncooperative games.

Download or read book Incompressible Computational Fluid Dynamics written by Max D. Gunzburger and published by Cambridge University Press. This book was released on 2009-01-11 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Incompressible computational fluid dynamics is an emerging and important discipline, with numerous applications in industry and science. Its methods employ rigourous mathematical analysis far beyond what is presently possible for compressible flows. Vortex methods, finite elements, and spectral methods are emphasised. Contributions from leading experts in the various sub-fields portray the wide-ranging nature of the subject. The book provides an entrée into the current research in the field. It can also serve as a source book for researchers and others who require information on methods and techniques.

Download or read book Fixed Point Theory in Modular Function Spaces written by Mohamed A. Khamsi and published by Birkhäuser. This book was released on 2015-03-24 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph provides a concise introduction to the main results and methods of the fixed point theory in modular function spaces. Modular function spaces are natural generalizations of both function and sequence variants of many important spaces like Lebesgue, Orlicz, Musielak-Orlicz, Lorentz, Orlicz-Lorentz, Calderon-Lozanovskii spaces, and others. In most cases, particularly in applications to integral operators, approximation and fixed point results, modular type conditions are much more natural and can be more easily verified than their metric or norm counterparts. There are also important results that can be proved only using the apparatus of modular function spaces. The material is presented in a systematic and rigorous manner that allows readers to grasp the key ideas and to gain a working knowledge of the theory. Despite the fact that the work is largely self-contained, extensive bibliographic references are included, and open problems and further development directions are suggested when applicable. The monograph is targeted mainly at the mathematical research community but it is also accessible to graduate students interested in functional analysis and its applications. It could also serve as a text for an advanced course in fixed point theory of mappings acting in modular function spaces.​

Download or read book Theory and Applications of Partial Functional Differential Equations written by Jianhong Wu and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 441 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract semilinear functional differential equations arise from many biological, chemical, and physical systems which are characterized by both spatial and temporal variables and exhibit various spatio-temporal patterns. The aim of this book is to provide an introduction of the qualitative theory and applications of these equations from the dynamical systems point of view. The required prerequisites for that book are at a level of a graduate student. The style of presentation will be appealing to people trained and interested in qualitative theory of ordinary and functional differential equations.

Download or read book Exact and Approximate Controllability for Distributed Parameter Systems written by Roland Glowinski and published by . This book was released on 2008-03-20 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: A thorough mathematical analysis of controllability problems with a detailed investigation of methods for solving them numerically.

Download or read book Fermat Days 85 Mathematics for Optimization written by J.-B. Hiriart-Urruty and published by Elsevier. This book was released on 1986-01-01 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimization, as examined here, ranges from differential equations to problems arising in Mechanics and Statistics. The main topics covered are: calculations of variations and nonlinear elasticity, optimal control, analysis and optimization in problems dealing with nondifferentiable data, duality techniques, algorithms in mathematical programming and optimal control.