Bernard Geurts – författare

This volume contains the proceedings of DLES4, the fourth international ERCOFTAC workshop on Direct and Large-Eddy Simulation which was held at the University of Twente, July 18-20, 2001. It contains an exposition and discussion of modeling and simulation approaches for complex flows. Fundamental turbulence - and modeling issues and elements from modern numerical analysis are at the heart of this field of interest. Present-day DNS and LES tend to be extended toward flows of realistic complexity, at practically relevant flow conditions and with the inclusion of additional complex physical phenomena such as arise for example in combustion research, environmental flows, multiphase applications and process-engineering. These extensions of DNS and LES are illustrated in the contributions, while an ongoing interest remains with sophisticated modeling and numerical approaches, paying attention to physical, mathematical and engineering aspects.

This volume presents a coherent account of contemporary computational approaches to turbulent flows. It aims to provide the reader with information about the current state-of-the-art as well as to stimulate directions for future research and development. The book puts particular emphasis on computational methods for incompressible and compressible turbulent flows as well as on methods for analysing and quantifying numerical errors in turbulent flow computations. This book aims to appeal to a broad audience of applied scientists and engineers who are involved in the development and application of computational fluid dynamics (CFD) methods for turbulent flows. The chapters were specifically composed to also constitute an advanced textbook for PhD candidates in the field of CFD and turbulence. The book can also be used as a textbook at the level of MSc or MEng studies in engineering, physics and applied mathematics departments.

This volume contains the Proceedings of DLES-5, the fifth international ERCOFTAC workshop on direct and large-eddy simulation which was held at the Munich university of Technology, August 27-29, 2003. It covers all aspects of DNS and LES, but also hybrid methods like RANS/LES coupling and detached-eddy simulations designed to provide answers to technical flow problems at reasonable computational cost. Being organized in four parts, the book covers issues in LES modelling and numerics in its first part, i.e. subgrid-scale modelling, wall models for LES and numerical techniques as well as error estimation. Laminar-turbulent transition phenomena in incompressible and compressible flows form the topic of part 2. Turbulent flows involving complex physical phenomena like multiphase and non-Newtonian effects, scalar transport, combustion, compressibility and noise generation are at the heart of part 3. Turbulent flows in complex geometries bridge the gap in part 4 to practical flow configurations in aerodynamics, turbomachinery and several other applied sciences.

This book contains a selection of the papers that were presented at the EUROMECH colloquium on particle-laden flow held at the University of Twente in 2006. The multiscale nature of this challenging field motivated the calling of the colloquium and reflects the central importance that the dispersion of particles in a flow has in various geophysical and environmental problems. The spreading of aerosols and soot in the air, the growth and dispersion of plankton blooms in seas and oceans, or the transport of sediment in rivers, estuaries and coastal regions are striking examples.

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 relevant to BSc/MSc students interested in mathematical modeling and simulation. It brings together analysis, calculus and numerical methods presented in a single coherent volume. Particular attention is given to engineering mathematics, addressing modeling, analysis, method development, implementation and testing of algorithms, as well as application to actual problems and critical interpretation of the results. The book can be used throughout bachelor programs and parts of masters programs, presenting a comprehensive suite of courses that link formal abstract thinking on the one hand to intuitive model formulation, critical algorithm development and interpretation of results on the other hand. The books contains numerous examples of practical applications from physics, technology, biology and chemistry. It also contains an introduction to Matlab and C for algorithm development and computational analysis. Software and solutions to selected problems are included.

Following the spirit of the series, the goal of this latest workshop is to establish a state-of-the-art of DNS and LES techniques for the computation and modeling of transitional/turbulent flows covering a broad scope of topics such as aerodynamics, acoustics, combustion, multiphase flows, environment, geophysics and bio-medical applications.

The workshop 'Direct and Large-Eddy Simulation-4' was held at the Uni­ versity ofTwente, July 18-20, 2001. DLES4is part of a series ofERCOFfAC workshops that originated at the University of Surrey in 1994. Over the years the DLES-series has grown into a major international venue focused on the development and application of direct and large-eddy simulation. Fundamental turbulence - and modeling issues but also elements from modem numerical analysis are at the heart of this field of interest, a fact which is clearly reflected by the contents of these proceedings. Modeling and simulation of complex flow phenomena forms a central ele­ ment in a large volume of scientific - and applied research. The problem of simulating turbulent flows and capturing their main dynamical features remains a highly motivating challenge. This three-day workshop focused on recent de­ velopments in numerical and physical modeling of complex flow phenomena concentrating on modem strategies in the field of direct and large-eddy simula­ tion. A major aim was to promote the exchange of ideas and problems from both industrial and academic background paying attention to physical, mathematical and engineering aspects.

This book presents a coherent account of contemporary computational approaches for turbulent flows. It aims to provide the reader with information about the current state of the art as well as to stimulate directions for future research and development. The book puts particular emphasis on computational methods for incompressible and compressible turbulent flows as well as on methods for analysing and quantifying numerical errors in turbulent flow computations. Apart from reviewing main research developments, new previously unpublished material is also included in many of the chapters. This book aims to appeal to a broad audience of applied scientists and engineers who are involved in the development and application of computational fluid dynamics (CFD) methods for turbulent flows. The readership includes academic researchers as well as CFD practitioners in industry. The chapters were specifically composed to also constitute an advanced textbook for PhD candidates in the field of CFD and turbulence. The book can also be used as a textbook at the level of MSc or MEng studies in engineering, physics and applied mathematics departments.

This volume contains the Proceedings of DLES-5, the fifth international ERCOFTAC workshop on direct and large-eddy simulation which was held at the Munich university of Technology, August 27-29, 2003. It covers all aspects of DNS and LES, but also hybrid methods like RANS/LES coupling and detached-eddy simulations designed to provide answers to technical flow problems at reasonable computational cost. Being organized in four parts, the book covers issues in LES modelling and numerics in its first part, i.e. subgrid-scale modelling, wall models for LES and numerical techniques as well as error estimation. Laminar-turbulent transition phenomena in incompressible and compressible flows form the topic of part 2. Turbulent flows involving complex physical phenomena like multiphase and non-Newtonian effects, scalar transport, combustion, compressibility and noise generation are at the heart of part 3. Turbulent flows in complex geometries bridge the gap in part 4 to practical flow configurations in aerodynamics, turbomachinery and several other applied sciences.

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.

This volume continues previous DLES proceedings books, presenting modern developments in turbulent flow research. It is comprehensive in its coverage of numerical and modeling techniques for fluid mechanics.After Surrey in 1994, Grenoble in 1996, Cambridge in 1999, Enschede in 2001, Munich in 2003, Poitiers in 2005, and Trieste in 2009, the 8th workshop, DLES8, was held in Eindhoven, The Netherlands, again under the auspices of ERCOFTAC. Following the spirit of the series, the goal of this workshop is to establish a state-of-the-art of DNS and LES techniques for the computation and modeling of transitional/turbulent flows covering a broad scope of topics such as aerodynamics, acoustics, combustion, multiphase flows, environment, geophysics and bio-medical applications. This gathering of specialists in the field  was a unique opportunity for discussions about the more recent advances in the prediction, understanding and control of turbulent flows in academic or industrial situations.

After Surrey in 1994, Grenoble in 1996, Cambridge in 1999, Enschede in 2001, Munich in 2003 and Poiters in 2005, the 7th Workshop, DLES7, will be held in Trieste, again under the auspices of ERCOFTAC. Following the spirit of the series, the goal of this latest workshop is to establish a state-of-the-art of DNS and LES techniques for the computation and modeling of transitional/turbulent flows covering a broad scope of topics such as aerodynamics, acoustics, combustion, multiphase flows, environment, geophysics and bio-medical applications. This gathering of specialists in the field should once again be a unique opportunity for discussions about the more recent advances in the prediction, understanding and control of turbulent flows in academic or industrial situations.

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.

This volume continues previous DLES proceedings books, presenting modern developments in turbulent flow research. It is comprehensive in its coverage of numerical and modeling techniques for fluid mechanics.After Surrey in 1994, Grenoble in 1996, Cambridge in 1999, Enschede in 2001, Munich in 2003, Poitiers in 2005, and Trieste in 2009, the 8th workshop, DLES8, was held in Eindhoven, The Netherlands, again under the auspices of ERCOFTAC. Following the spirit of the series, the goal of this workshop is to establish a state-of-the-art of DNS and LES techniques for the computation and modeling of transitional/turbulent flows covering a broad scope of topics such as aerodynamics, acoustics, combustion, multiphase flows, environment, geophysics and bio-medical applications. This gathering of specialists in the field  was a unique opportunity for discussions about the more recent advances in the prediction, understanding and control of turbulent flows in academic or industrial situations.