Alexander J. Smits – författare

A good understanding of turbulent compressible flows is essential to the design and operation of high-speed vehicles. Such flows occur, for example, in the external flow over the surfaces of supersonic aircraft, and in the internal flow through the engines. Our ability to predict the aerodynamic lift, drag, propulsion and maneuverability of high-speed vehicles is crucially dependent on our knowledge of turbulent shear layers, and our understanding of their behavior in the presence of shock waves and regions of changing pressure. Turbulent Shear Layers in Supersonic Flow provides a comprehensive introduction to the field, and helps provide a basis for future work in this area. Wherever possible we use the available experimental work, and the results from numerical simulations to illustrate and develop a physical understanding of turbulent compressible flows.

Turbulence at high Reynolds number is interesting from a fundamental point of view, in that most theories of turbulence make very specific predictions regarding the behaviour of turbulence with increasing Reynolds number. From a more practical point of view, many very important applications of high Reynolds number flow pertain to the motion of large vehicles, atmospheric and other geophysical flows where the understanding of climate changes and the prediction of destructive weather effects hinges to a significant extent on our appreciation of high-Reynolds number turbulence behaviour. This volume contains selected papers from the IUTAM Symposium entitled "Reynolds Number Scaling in Turbulent Flow," held on September 11-13, 2002 in Princeton, NJ, USA. The purpose of the symposium was to bring together many of the world's experts in this area to appraise the new experimental results, discuss new scaling laws and turbulence models, and to enhance our mutual understanding of turbulence. This book should contribute to the knowledge of turbulence, and help guide future experimental, numerical and theoretical research in this area.

A good understanding of turbulent compressible flows is essential to the design and operation of high-speed vehicles. Such flows occur, for example, in the external flow over the surfaces of supersonic aircraft, and in the internal flow through the engines. Our ability to predict the aerodynamic lift, drag, propulsion and maneuverability of high-speed vehicles is crucially dependent on our knowledge of turbulent shear layers, and our understanding of their behavior in the presence of shock waves and regions of changing pressure. Turbulent Shear Layers in Supersonic Flow provides a comprehensive introduction to the field, and helps provide a basis for future work in this area. Wherever possible we use the available experimental work, and the results from numerical simulations to illustrate and develop a physical understanding of turbulent compressible flows.

Throughout history, flow visualization has been an important tool in fluid dynamics research. It has been used extensively in the fields of engineering, physics, medical science, meteorology, oceanography and sport aerodynamics, to name just a few. The importance of flow visualization led Professor F N M Brown (1971) of the University of Notre-Dame to comment, “… A man is not a dog to smell out each individual track, he is a man to see, and seeing, to analyze…” This statement encapsulates the importance of first visualizing the flow before proceeding with detailed measurement and mathematical modeling. In addition, there is a great deal of esthetic pleasure to be gained from seeing the results of flow visualization. This aspect of flow visualization reaches out to the general public: we are all familiar with the aspect of clouds in the sky, the trail of cigarette smoke, and the swirling patterns to be seen in rivers and seas.Unlike previous publications which concentrated mainly on the theoretical aspect of flow visualization, this book focuses on the techniques required to perform high quality flow visualization. It is aimed primarily at the practitioner of flow visualization studies. Obtaining good flow visualization results is, in many ways, more an art than a science, and experience plays a deciding role. Hence each chapter of this invaluable volume has been written by an expert in a particular technique.

This volume presents selected papers from the IUTAM Symposium on Reynolds Number Scaling in Turbulent Flow, convened in Princeton, NJ, USA, September I1-13, 2002. The behavior ofturbulence at high Reynolds number is interesting from a fundamental point of view, in that most theories of turbulence make very specific predictions in the limit of infinite Reynolds number. From a more practical point of view, there exist many applications that involve turbulent flow where the Reynolds numbers are extremely large. For example, large vehicles such as submarines and commercial transports operate at Reynolds 9 numbers based on length ofthe order oft0 , and industrial pipe flows cover a 7 very wide range of Reynolds numbers up to 10 • Many very important applications of high Reynolds number flow pertain to atmospheric and other geophysical flows where extremely high Reynolds numbers are the rule rather than the exception, and the understanding of climate changes and the prediction of destructive weather effects hinges to some extent on our appreciation ofhigh-Reynolds number turbulence behavior. The important effects of Reynolds number on turbulence has received a great deal of recent attention. The objective of the Symposium was to bring together many of the world''s experts in this area to appraise the new experimental results, discuss new scaling laws and turbulence models, and to enhance our mutual understanding of turbulence.