Pierre Sagaut – författare

This book summarizes the most recent theoretical, computational and experimental results dealing with homogeneous turbulence dynamics. A large class of flows is covered: flows governed by anisotropic production mechanisms (e.g. shear flows) and flows without production but dominated by waves (e.g. homogeneous rotating or stratified turbulence). Compressible turbulent flows are also considered. In each case, main trends are illustrated using computational and experimental results, while both linear and nonlinear theories and closures are discussed. Details about linear theories (e.g. Rapid Distortion Theory and variants) and nonlinear closures (e.g. EDQNM) are provided in dedicated chapters, following a fully unified approach. The emphasis is on homogeneous flows, including several interactions (rotation, stratification, shear, shock waves, acoustic waves, and more) which are pertinent to many application fields - from aerospace engineering to astrophysics and earth sciences.

Noise pollution around airports, trains, and industries increasingly attracts environmental concern and regulation. Designers and researchers have intensified the use of large-eddy simulation (LES) for noise reduced industrial design and acoustical research. This 2007 book, written by 30 experts, presents the theoretical background of acoustics and of LES, followed by details about numerical methods, e.g. discretization schemes, boundary conditions, coupling aspects. Industrially relevant, hybrid RANS/LES techniques for acoustic source predictions are presented in detail. Many applications are featured ranging from simple geometries for mixing layers and jet flows to complex wing and car geometries. Selected applications include scientific investigations at industrial and university research institutions.

Noise pollution around airports, trains, and industries increasingly attracts environmental concern and regulation. Designers and researchers have intensified the use of large-eddy simulation (LES) for noise reduced industrial design and acoustical research. This 2007 book, written by 30 experts, presents the theoretical background of acoustics and of LES, followed by details about numerical methods, e.g. discretization schemes, boundary conditions, coupling aspects. Industrially relevant, hybrid RANS/LES techniques for acoustic source predictions are presented in detail. Many applications are featured ranging from simple geometries for mixing layers and jet flows to complex wing and car geometries. Selected applications include scientific investigations at industrial and university research institutions.

Computational resources have developed to the level that, for the first time, it is becoming possible to apply large-eddy simulation (LES) to turbulent flow problems of realistic complexity. Many examples can be found in technology and in a variety of natural flows. This puts issues related to assessing, assuring, and predicting the quality of LES into the spotlight. Several LES studies have been published in the past, demonstrating a high level of accuracy with which turbulent flow predictions can be attained, without having to resort to the excessive requirements on computational resources imposed by direct numerical simulations. However, the setup and use of turbulent flow simulations requires a profound knowledge of fluid mechanics, numerical techniques, and the application under consideration. The susceptibility of large-eddy simulations to errors in modelling, in numerics, and in the treatment of boundary conditions, can be quite large due to nonlinear accumulation of different contributions over time, leading to an intricate and unpredictable situation. A full understanding of the interacting error dynamics in large-eddy simulations is still lacking. To ensure the reliability of large-eddy simulations for a wide range of industrial users, the development of clear standards for the evaluation, prediction, and control of simulation errors in LES is summoned. The workshop on Quality and Reliability of Large-Eddy Simulations, held October 22-24, 2007 in Leuven, Belgium (QLES2007), provided one of the first platforms specifically addressing these aspects of LES.

This textbook is based on the lectures on turbulence given in the Masters programme at Université Pierre et Marie Curie and Ecole Polytechnique. The book covers the classic topics on turbulence that includes: introduction to fundamentals of statistical and spectral analysis, dimensional analysis, Kolmogorov theory and energy cascade, the hierarchy of turbulent flows ranging from isotropic turbulence to non-homogeneous shear flows, and extension to compressible turbulence illuminated using Kovasznay model decomposition.A substantial section of this volume is devoted to exercises and problems to guide readers through the book in applying the theories learnt to the problems provided. Furthermore, all-important exercises and problems are first presented in the usual short “workout” fashion, followed by the full solution to demonstrate the process.Turbulence is a multidisciplinary subject that cut across engineering and earth sciences; covering areas such as pollution control, global warming and acoustic pollution. Therefore, in all chapters, the usual Navier-Stokes equations supplemented with a passive scalar equation will be used to serve as a simplified model for pollutant or temperature, intended to give readers a comprehensive view of turbulent scalar field dynamics.Lecture Notes on Turbulence: Problems and Solutions provides readers with a comprehensive introduction to turbulence dynamics and modelling, and will be of interest to Masters students, PhD students and experienced professionals who wish to get an insight into the field of turbulence.

This textbook is based on the lectures on turbulence given in the Masters programme at Université Pierre et Marie Curie and Ecole Polytechnique. The book covers the classic topics on turbulence that includes: introduction to fundamentals of statistical and spectral analysis, dimensional analysis, Kolmogorov theory and energy cascade, the hierarchy of turbulent flows ranging from isotropic turbulence to non-homogeneous shear flows, and extension to compressible turbulence illuminated using Kovasznay model decomposition.A substantial section of this volume is devoted to exercises and problems to guide readers through the book in applying the theories learnt to the problems provided. Furthermore, all-important exercises and problems are first presented in the usual short “workout” fashion, followed by the full solution to demonstrate the process.Turbulence is a multidisciplinary subject that cut across engineering and earth sciences; covering areas such as pollution control, global warming and acoustic pollution. Therefore, in all chapters, the usual Navier-Stokes equations supplemented with a passive scalar equation will be used to serve as a simplified model for pollutant or temperature, intended to give readers a comprehensive view of turbulent scalar field dynamics.Lecture Notes on Turbulence: Problems and Solutions provides readers with a comprehensive introduction to turbulence dynamics and modelling, and will be of interest to Masters students, PhD students and experienced professionals who wish to get an insight into the field of turbulence.

The book aims to provide the reader with an updated general presentation of multiscale/multiresolution approaches in turbulent flow simulations. All modern approaches (LES, hybrid RANS/LES, DES, SAS) are discussed and recast in a global comprehensive framework. Both theoretical features and practical implementation details are addressed. Some full scale applications are described, to provide the reader with relevant guidelines to facilitate a future use of these methods.

This unique book gives a general unified presentation of the use of the multiscale/multiresolution approaches in the field of turbulence. The coverage ranges from statistical models developed for engineering purposes to multiresolution algorithms for the direct computation of turbulence. It provides the only available up-to-date reviews dealing with the latest and most advanced turbulence models (including LES, VLES, hybrid RANS/LES, DES) and numerical strategies.The book aims at providing the reader with a comprehensive description of modern strategies for turbulent flow simulation, ranging from turbulence modeling to the most advanced multilevel numerical methods.

This book provides state-of-the-art results and theories in homogeneous turbulence, including anisotropy and compressibility effects with extension to quantum turbulence, magneto-hydodynamic turbulence and turbulence in non-newtonian fluids.

This book provides state-of-the-art results and theories in homogeneous turbulence, including anisotropy and compressibility effects with extension to quantum turbulence, magneto-hydodynamic turbulence and turbulence in non-newtonian fluids.

L'ouvrage présente la technique de simulation des grandes échelles. Les bases mathématiques et les hypothèses physiques employées sont rappelées. Les concepts de modélisation structurelle et de modélisation fonctionnelle sont introduits, et servent à établir une liste exhaustive, unique à ce jour, des modèles sous-maille existants. Outre la description de ces modèles, le lecteur trouvera des éléments théoriques et des détails pratiques concernant leur mise en oeuvre. L'analyse des résultats est également discutée et illustrée par des exemples concrets. L'ouvrage permettra aux novices de s'initier à la simulation des grandes échelles et aux praticiens confirmés de découvrir des aspects nouveaux ou méconnus de cette discipline.

The "Turbulence and Interactions 2006" (TI2006) conference was held on the island of Porquerolles, France, May 29-June 2, 2006. The scientific sponsors of the conference were * Association Francaise de Mecanique, * CD-adapco, * DGA * Ecole Polytechnique Federale de Lausanne (EPFL), * ERCOFTAC : European Research Community on Flow, Turbulence and Combustion, * FLUENT, * The French Ministery of Foreign Affairs, * Laboratoire de Modelisation en Mecanique, Paris 6, * ONERA. The conference was a unique event. Never before have so many organisations concerned with turbulence works come together in one conference. As the title "Turbulence and Interactions" anticipated, the workshop was not run with parallel sessions but instead of one united gathering where people had strong interactions and discussions. Many of the 85 or so attendants were veterans of previous ERCOFTAC conferences. Some young researchers attended their very first int- national meeting. The organisers were fortunate in obtaining the presence of the following - vited speakers: N. Adams (TUM, Germany), C. Cambon (ECL, France), J.-P. Dussauge (Polytech Marseille, France), D.A. Gosman (Imperial College, UK), Y.Kaneda (Nagoya University, Japan), O. Simonin (IMFT, France), G. Tryggvason (WPI, USA), D. Veynante (ECP, France), F. Waleffe (University of Wisconsin, USA), Y.K. Zhou (University of California, USA). The topics covered by the 59 papers ranged from experimental results through theory to computations. The papers of the conference went through the usual - viewing process for two special issues of international journals : Computers and Fluids, and Flow, Turbulence and Combustion.

The "Turbulence and Interactions 2009" (TI2009) conference was held in Saint- Luce on the island of La Martinique, France, on May 31-June 5, 2009. The sci- tific sponsors of the conference were * DGA * Ecole Polytechnique Federale de Lausanne (EPFL), * ERCOFTAC : European Research Community on Flow, Turbulence and Combustion, * Institut Jean Le Rond d'Alembert, Paris, * ONERA. This second TI conference was very successful as it attracted 65 researchers from 17 countries. The magnificent venue and the beautiful weather helped the participants to discuss freely and casually, share ideas and projects, and spend very good times all together. The organisers were fortunate in obtaining the presence of the following - vited speakers: L. Fuchs (KTH, Stockholm and Lund University), J. Jimenez (Univ. Politecnica Madrid), C.-H. Moeng (NCAR), A. Scotti (University of North Carolina), L. Shen (Johns Hopkins University) and A.J. Smits (Princeton Univ- sity). The topics covered by the 62 contributed papers ranged from experimental results through theory to computations. They represent a snapshot of the state-- the-art in turbulence research.The papers of the conference went through the usual reviewing process and the result is given in this book of Proceedings. In the present volume, the reader will find the keynote lectures followed by the contributed talks given in alphabetical order of the first author.

The "Turbulence and Interactions 2009" (TI2009) conference was held in Saint- Luce on the island of La Martinique, France, on May 31-June 5, 2009. The sci- tific sponsors of the conference were * DGA * Ecole Polytechnique Federale de Lausanne (EPFL), * ERCOFTAC : European Research Community on Flow, Turbulence and Combustion, * Institut Jean Le Rond d'Alembert, Paris, * ONERA. This second TI conference was very successful as it attracted 65 researchers from 17 countries. The magnificent venue and the beautiful weather helped the participants to discuss freely and casually, share ideas and projects, and spend very good times all together. The organisers were fortunate in obtaining the presence of the following - vited speakers: L. Fuchs (KTH, Stockholm and Lund University), J. Jimenez (Univ. Politecnica Madrid), C.-H. Moeng (NCAR), A. Scotti (University of North Carolina), L. Shen (Johns Hopkins University) and A.J. Smits (Princeton Univ- sity). The topics covered by the 62 contributed papers ranged from experimental results through theory to computations. They represent a snapshot of the state-- the-art in turbulence research.The papers of the conference went through the usual reviewing process and the result is given in this book of Proceedings. In the present volume, the reader will find the keynote lectures followed by the contributed talks given in alphabetical order of the first author.

The "Turbulence and Interactions 2006" (TI2006) conference was held on the island of Porquerolles, France, May 29-June 2, 2006. The scientific sponsors of the conference were * Association Francaise de Mecanique, * CD-adapco, * DGA * Ecole Polytechnique Federale de Lausanne (EPFL), * ERCOFTAC : European Research Community on Flow, Turbulence and Combustion, * FLUENT, * The French Ministery of Foreign Affairs, * Laboratoire de Modelisation en Mecanique, Paris 6, * ONERA. The conference was a unique event. Never before have so many organisations concerned with turbulence works come together in one conference. As the title "Turbulence and Interactions" anticipated, the workshop was not run with parallel sessions but instead of one united gathering where people had strong interactions and discussions. Many of the 85 or so attendants were veterans of previous ERCOFTAC conferences. Some young researchers attended their very first int- national meeting. The organisers were fortunate in obtaining the presence of the following - vited speakers: N. Adams (TUM, Germany), C. Cambon (ECL, France), J.-P. Dussauge (Polytech Marseille, France), D.A. Gosman (Imperial College, UK), Y.Kaneda (Nagoya University, Japan), O. Simonin (IMFT, France), G. Tryggvason (WPI, USA), D. Veynante (ECP, France), F. Waleffe (University of Wisconsin, USA), Y.K. Zhou (University of California, USA). The topics covered by the 59 papers ranged from experimental results through theory to computations. The papers of the conference went through the usual - viewing process for two special issues of international journals : Computers and Fluids, and Flow, Turbulence and Combustion.

Computational resources have developed to the level that, for the first time, it is becoming possible to apply large-eddy simulation (LES) to turbulent flow problems of realistic complexity. Many examples can be found in technology and in a variety of natural flows. This puts issues related to assessing, assuring, and predicting the quality of LES into the spotlight. Several LES studies have been published in the past, demonstrating a high level of accuracy with which turbulent flow predictions can be attained, without having to resort to the excessive requirements on computational resources imposed by direct numerical simulations. However, the setup and use of turbulent flow simulations requires a profound knowledge of fluid mechanics, numerical techniques, and the application under consideration. The susceptibility of large-eddy simulations to errors in modelling, in numerics, and in the treatment of boundary conditions, can be quite large due to nonlinear accumulation of different contributions over time, leading to an intricate and unpredictable situation. A full understanding of the interacting error dynamics in large-eddy simulations is still lacking. To ensure the reliability of large-eddy simulations for a wide range of industrial users, the development of clear standards for the evaluation, prediction, and control of simulation errors in LES is summoned. The workshop on Quality and Reliability of Large-Eddy Simulations, held October 22-24, 2007 in Leuven, Belgium (QLES2007), provided one of the first platforms specifically addressing these aspects of LES.

The second Workshop on "Quality and Reliability of Large-Eddy Simulations",QLES2009, was held at the University of Pisa from September 9 to September 11,2009. Its predecessor, QLES2007, was organized in 2007 in Leuven (Belgium). Thefocus of QLES2009 was on issues related to predicting, assessing and assuring thequality of LES.The main goal of QLES2009 was to enhance the knowledge on error sources andon their interaction in LES and to devise criteria for the prediction and optimizationof simulation quality, by bringing together mathematicians, physicists and engineersand providing a platform specifically addressing these aspects for LES. Contributions were made by leading experts in the field.The present book contains the written contributions to QLES2009 and is dividedinto three parts, which reflect the main topics addressed at the workshop: (i) SGSmodeling and discretization errors; (ii) Assessment and reduction of computationalerrors; (iii) Mathematical analysis and foundation for SGS modeling.