Jochen Fröhlich – författare

This book gathers the proceedings of the 11th workshop on Direct and Large Eddy Simulation (DLES), which was held in Pisa, Italy in May 2017. The event focused on modern techniques for simulating turbulent flows based on the partial or full resolution of the instantaneous turbulent flow structures, as Direct Numerical Simulation (DNS), Large-Eddy Simulation (LES) or hybrid models based on a combination of LES and RANS approaches. In light of the growing capacities of modern computers, these approaches have been gaining more and more interest over the years and will undoubtedly be developed and applied further. The workshop offered a unique opportunity to establish a state-of-the-art of DNS, LES and related techniques for the computation and modeling of turbulent and transitional flows and to discuss about recent advances and applications.This volume contains most of the contributed papers, which were submitted and further reviewed for publication. They cover advances incomputational techniques, SGS modeling, boundary conditions, post-processing and data analysis, and applications in several fields, namely multiphase and reactive flows, convection and heat transfer, compressible flows, aerodynamics of airfoils and wings, bluff-body and separated flows, internal flows and wall turbulence and other complex flows.

This volume reflects the state of the art of numerical simulation of transitional and turbulent flows and provides an active forum for discussion of recent developments in simulation techniques and understanding of flow physics. Following the tradition of earlier DLES workshops, these papers address numerous theoretical and physical aspects of transitional and turbulent flows. At an applied level it contributes to the solution of problems related to energy production, transportation, magneto-hydrodynamics and the environment. A special session is devoted to quality issues of LES. The ninth Workshop on 'Direct and Large-Eddy Simulation' (DLES-9) was held in Dresden, April 3-5, 2013, organized by the Institute of Fluid Mechanics at Technische Universität Dresden.This book is of interest to scientists and engineers, both at an early level in their career and at more senior levels.

This volume reflects the state of the art of numerical simulation of transitional and turbulent flows and provides an active forum for discussion of recent developments in simulation techniques and understanding of flow physics. Following the tradition of earlier DLES workshops, these papers address numerous theoretical and physical aspects of transitional and turbulent flows. At an applied level it contributes to the solution of problems related to energy production, transportation, magneto-hydrodynamics and the environment. A special session is devoted to quality issues of LES. The ninth Workshop on 'Direct and Large-Eddy Simulation' (DLES-9) was held in Dresden, April 3-5, 2013, organized by the Institute of Fluid Mechanics at Technische Universität Dresden.This book is of interest to scientists and engineers, both at an early level in their career and at more senior levels.

This book addresses nearly all aspects of the state of the art in LES & DNS of turbulent flows, ranging from flows in biological systems and the environment to external aerodynamics, domestic and centralized energy production, combustion, propulsion as well as applications of industrial interest. Following the advances in increased computational power and efficiency, several contributions are devoted to LES & DNS of challenging applications, mainly in the area of turbomachinery, including flame modeling, combustion processes and aeroacoustics.The book includes work presented at the tenth Workshop on 'Direct and Large-Eddy Simulation' (DLES-10), which was hosted in Cyprus by the University of Cyprus, from May 27 to 29, 2015. The goal of the workshop was to establish a state of the art in DNS, LES and related techniques for the computation and modeling of turbulent and transitional flows. The book is of interest to scientists and engineers, both in the early stages of their career and at a more senior level.

This book addresses nearly all aspects of the state of the art in LES & DNS of turbulent flows, ranging from flows in biological systems and the environment to external aerodynamics, domestic and centralized energy production, combustion, propulsion as well as applications of industrial interest. Following the advances in increased computational power and efficiency, several contributions are devoted to LES & DNS of challenging applications, mainly in the area of turbomachinery, including flame modeling, combustion processes and aeroacoustics.The book includes work presented at the tenth Workshop on 'Direct and Large-Eddy Simulation' (DLES-10), which was hosted in Cyprus by the University of Cyprus, from May 27 to 29, 2015. The goal of the workshop was to establish a state of the art in DNS, LES and related techniques for the computation and modeling of turbulent and transitional flows. The book is of interest to scientists and engineers, both in the early stages of their career and at a more senior level.

This volume contains results of a European project on Large Eddy Simulation (LES) of the flow around an airfoil. The main objective of the LESFOIL project was to assess the suitability of LES for airfoil flow. In conclusion, preliminary work was carried out such as development of numerical methods, and subgrid modelling in geometrically simple flows such as fully developed channel flow and periodic flow in a channel with a curved hill-shaped surface. Accurate LES of wall-bounded flow requires fine cells in the near-wall region in all coordinate directions. In an attempt to release this constraint, a large part of the LESFOIL project was aimed at developing and validating different approximate near-wall treatments. In the second half of the book, several LESs of the flow around the Aerospatiale-A airfoil are presented, using different numerical methods, grids, SGS models and near-wall treatments.

Large Eddy Simulation is a relatively new and still evolving computatio­ nal strategy for predicting turbulent flows. It is now widely used in research to elucidate fundamental interactions in physics of turbulence, to predict phe­ nomena which are closely linked to the unsteady features of turbulence and to create data bases against which statistical closure models can be asses­ sed. However, its applicability to complex industrial flows, to which statisti­ cal models are applied routinely, has not been established with any degree of confidence. There is, in particular, a question mark against the prospect of LES becoming an economically tenable alternative to Reynolds-averaged N avier-Stokes methods at practically high Reynolds numbers and in complex geometries. Aerospace flows pose particularly challenging problems to LES, because of the high Reynolds numbers involved, the need to resolve accura­ tely small-scale features in the thin and often transitional boundary layers developing on aerodynamic surfaces. When the flow also contains a separated region - due to high incidence, say - the range and disparity of the influen­ tial scales to be resolved is enormous, and this substantially aggravates the problems of resolution and cost. It is just this combination of circumstances that has been at the heart of the project LESFOIL to which this book is devoted. The project combined the efforts, resources and expertise of 9 partner organisations, 4 universities, 3 industrial companies and 2 research institu­ tes.

Micro and nano-fluidics concerns fluid dynamics occurring in devices or flow configurations with minimum design length measured in micrometers or smaller. The behavior of fluids at these scales is quite different from that at the macroscopic level due to the presence of surface tension effects, wetting phenomena, Brownian diffusion and hydrodynamic interactions with immersed particles and microstructures. These effects cannot be generally represented in a classical homogeneous continuum framework. However, this triggers the development of new tools to investigate and simulate problems at the meso-scopic level.This book contains a collection of works presented at the IUTAM Symposium on Advances on Micro and Nano-fluidics held in Dresden in 2007. It covers several subjects of wide interest for micro and nano-fluidics applications focusing on both, analytical and numerical approaches. Topics covered in particular include multi-scale particle methods for numerical simulations, liquid-wall interactions and modeling approaches, modeling of immersed nano-scale structures, organized flow behavior at micro and nano-scales, and methods for control of micro- and nano-scale flows.

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.

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.

Micro and nano-fluidics concerns fluid dynamics occurring in devices or flow configurations with minimum design length measured in micrometers or smaller. The behavior of fluids at these scales is quite different from that at the macroscopic level due to the presence of surface tension effects, wetting phenomena, Brownian diffusion and hydrodynamic interactions with immersed particles and microstructures. These effects cannot be generally represented in a classical homogeneous continuum framework. However, this triggers the development of new tools to investigate and simulate problems at the meso-scopic level.This book contains a collection of works presented at the IUTAM Symposium on Advances on Micro and Nano-fluidics held in Dresden in 2007. It covers several subjects of wide interest for micro and nano-fluidics applications focusing on both, analytical and numerical approaches. Topics covered in particular include multi-scale particle methods for numerical simulations, liquid-wall interactions and modeling approaches, modeling of immersed nano-scale structures, organized flow behavior at micro and nano-scales, and methods for control of micro- and nano-scale flows.

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.