Recent Results in Laminar-Turbulent Transition: Selected numerical and experimental contributions from the DFG priority programme ‘Transition’ in Germany PDF
Preview Recent Results in Laminar-Turbulent Transition: Selected numerical and experimental contributions from the DFG priority programme ‘Transition’ in Germany
86 Notes on Numerical Fluid Mechanics and Multidisciplinary Design (NNFM) Editors E. H. HirschellMiinchen K. FujiilKanagawa w. Haase/Miinchen B. van Leer/Ann Arbor M. A. Leschziner/London M. Pandolfi/Torino J. PeriauxiParis A. Rizzi/Stockholm B. RouxlMarseille Springer-Verlag Berlin Heidelberg GmbH ONLINE LIBRARY Engineering http://www.springer.de/engine/ Recent Results in Laminar Turbulent Transition Selected numerical and experimental contributions from the DFG priority programme 'Transition' in Germany Siegfried Wagner, Markus Kloker, Ulrich Rist (Editors) t Springer Prof. Dr. Siegfried Wagner Dr. Markus Kloker Dr. Ulrich Rist Universitat Stuttgart Institut fiir Aerodynamik und Gasdynamik Pfaffenwaldring 21 70550 Stuttgart Germany siegfried. [email protected] [email protected] [email protected] Library of Congress Cataloging-in-Publication-Data Recent results in laminar-turbulent transition: selected numerical and experimental contributions from the DFG Priority Programme "Transition" in Germany 1 Siegfried Wagner, Markus Kloker, Ulrich Rist (editors). p. cm. --(Notes on numerical fluid mechanics and multidisciplinary design, ISSN 0179-9614; 86) Includes bibliographical references. 1. Fluid dynamics. 2. Laminar flow. 3. Turbulence. 4. Boundary layer. I. Wagner, Siegfried. II Klo ker, Markus. III Rist, Ulrich. IV. DFG Verbund-Schwerpunktprogramm Transition. V. Series. TA357.R392004 532'.0525--dc22 This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitations, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Dupli cation of this publication or parts thereof is permitted only under the provisions of the German copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer-Verlag. Violations are liable for prosecution under the German Copyright Law. http://www.springer.de ISBN 978-3-642-07345-8 ISBN 978-3-540-45060-3 (eBook) DOI 10.1007/978-3-540-45060-3 © Springer-Verlag Berlin Heidelberg 2004 Originally published by Springer-Verlag Berlin Heidelberg New York in 2004 Softcover reprint of the hardcover 1s t edition 2004 The use of general descriptive names, registered names trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Typesetting: camera-ready by editors Cover design: deblik Berlin Printed on acid free paper 62/3020/M -543 2 1 0 NNFM Editor Addresses Pro£ Dr. Ernst Heinrich Hirschel Prof. Dr. Maurizio Pandolfi (General editor) Politecnico di Torino Herzog-Heinrich-Weg 6 Dipartimento di Ingegneria D-85604 Zorneding Aeronautica e Spaziale Germany Corso Duca degli Abruzzi, 24 E-mail: [email protected] 1-10129 Torino Italy Prof. Dr. Kozo Fujii E-mail: [email protected] Space Transportation Research Division Prof. Dr. Jacques Periaux The Institute of Space Dassault Aviation and Astronautical Science 78, Quai Marcel Dassault 3-1-1, Yoshinodai, Sagamihara, F-92552 St. Cloud Cedex Kanagawa,229-85lO France Japan E-mail: [email protected] E-mail: [email protected] Prof. Dr. Arthur Rizzi Dr. Werner Haase Department of Aeronautics Hohenkirchener Str.19d KTH Royal Institute of Technology D-85662 Hohenbrunn Teknikringen 8 Germany S-10044 Stockholm E-mail: [email protected] Sweden E-mail: [email protected] Prof. Dr. Bram van Leer Department of Aerospace Engineering Dr. Bernard Roux The University of Michigan L3M - IMT La Jetee Ann Arbor, MI 48lO9-2140 Technopole de Chateau-Gombert USA F-13451 Marseille Cedex 20 E-mail: [email protected] France E-mail: [email protected] Prof. Dr. Michael A. Leschziner Imperial College of Science, Technology and Medicine Aeronautics Department Prince Consort Road London SW7 2BY u.K. E-mail: [email protected] Preface Methodic investigations of laminar-turbulent transition in wall-bounded she ar flows under controlled conditions are essential for untangling the various complex phenomena of the transition process occurring in flows at practical conditions. They allow understanding of the instability processes of the la minar flow, and thus enable the development of tools for flow control. On the one hand the laminar flow regime can be extended by delaying transition to reduce viscous drag, and on the other hand large-scale flow disturbances or transition can be forced in order to enhance momentum and mass ex change. Thus flow separation can be prevented, or mixing of fuel and air in combustion engines enhanced, for instance. The "DFG Verbund-Schwerpunktprogramm Transition" - a cooperative priority research program of universities, research establishments and indu stry in Germany - has been launched in April 1996 with the aim to explore transition by a coordinated use, development and validation of advanced experimental techniques and theoretical/numerical simulation methods, bin ding together all the appropriate resources available in Germany. At the very beginning of the six-year research period specifically selected test problems were to be investigated by various theoretical and experimental methods to identify and possibly rule out inadequate numerical or experimental methods. With respect to experiments it was planned to use multi-sensor-surface measuring techniques, the infrared measuring technique, and particle image velocimetry (PlV) in addition to hot-wire techniques to get instantaneous images of flows in sections, on surfaces, or within the complete flow field. These methods provide a high information density allowing a detailed infor mation about complex three-dimensional and unsteady flows as well as the resolution of complex flow structures. For gaining insight into the proces ses and mechanisms of transition direct numerical simulations (DNS) were to be performed. Proper, advanced-numerics DNS have the potential to reliably simulate flow physical phenomena of any amplitude at well-defined conditions, without uncontrolled (background) disturbances or empirical flow modelling, from the very laminar flow up to the turbulent regime. The flow configurations treated are still geometrically simple, but we do point out that this is not primarily enforced by computational restrictions but by the un derstanding that simulating too complex or big a problem does often not help to understand it but simply is a feasibility or eye-catcher study without lasting value. Therefore, basic flow configurations have been an important element of this research program. The parabolized stability equations (PSE), a non-local instability tracking method using disturbance differential equati ons parabolized in streamwise direction, have also been used to investigate non-local disturbance effects and to study receptivity and weakly non-linear disturbance interactions. Additionally, advanced local methods, like equi librium solutions and the solution of partial-derivative eigenvalue problems (two-dimensional instead of one-dimensional) have been employed. VII A specialty were carefully planned flight tests performed by different uni versity groups with a common motor glider, by DLR (the German aerospace centre) with an own plane, and by Airbus industries using an airliner A320. Among these partners the know-how exchange was very useful. Moreover, the investigation of analogous flow situations by various theoretical/numerical and experimental methods guaranteed a high level of mutual stimulation. From this concerted actions a high level of success could be expected and has been regarded mandatory to make a remarkable step forward in transition re search. We do not want to conceal that there were some difficulties in keeping the cooperation alive up to the program end. Not due to personal or scientific misunderstandings, rather due to the organizational in-homogeneity of the contributing parties and due to strategic reorganisations at DLR and indu stry some convincing effort was needed so that the work could be adequately finished at these places. What are the lasting outcomes of the programme? Browse through the articles and find what we see: a wealth of internationally recognized results that reflect the steps marched forward on the way to understanding and advancing management of wall-bounded flows. Moreover, the concepts and methods successfully used and the experi ences made in the area of transition can, and in our view, have to be used (with little adaptation) also within turbulence research. In the area of turbu lence modelling a certain saturation has become obvious which means that no further progress can be expected, especially when transition phenomena, three-dimensional, or separated shear flows occur. This is due to inherent conflicts with some basic flow-physical mechanisms in the traditional ap proach. Therefore, the following hypotheses were agreed upon the partners within the final phase of the programme: • Turbulence modelling does not involve the dynamic, partially determi nistic character of turbulent flows • High-order numerical tools have to be used, and any modelling proce dures have to be decoupled from the discretization and numerics. The numerical methods must be verified, i.e. the numerics must be shown to accurately solve only the employed equations, before they are 'vali dated' by comparisons with experimental results. • The role of boundary conditions in experiments has to be carefully checked also for investigations of turbulence. "Turbulence levels" have not only to be quantified but also qualified. • Three-dimensionality and unsteadiness is often inherent in nominally (averaged) two-dimensional, steady flows. Averaging is a critical ope ration and is often misleading. Unfortunately, this last step in flow physical modelling could not be rea lised in the planned manner because of restrictions in budget. In addition, VIII research people performing turbulence simulations with standard methods preferred to continue research on this basis rather than revisit fundamental problems with improved tools. Nevertheless, the research project has been successful within the last two years and we are sure that the validity of the conclusions drawn for turbulence research will last. On behalf of all Verbundschwerpunktprogramm researchers we greatly appreciate the support by the Deutsche Forschungsgemeinschaft, DFG (the national research council), the Ministerium fur Forschung und Technologie, BMFT (the Ministry of Research and Technology), and by the Deutsche Airbus AG (German Airbus). We also want to honour the Schwerpunktprogramm contributions of di stinct German transition researchers who passed away during the programme: Horst Bestek, Universitat Stuttgart; Hans Bippes, and Uwe Dallman, both DLR G6ttingen. The articles in this book underwent a careful reviewing process; we are grateful to the reviewers who are listed below. Likewise we are grateful to Prof. Dr. E.H. Hirschel as the General Editor of the "Notes on Numerical Fluid Mechanics and Multidisciplinary Design", and to the Springer-Verlag for the opportunity to publish the results of the research program. March 2003, S. Wagner M. Kloker U. Rist IX List of Reviewers The following experts have spent time to review the manuscripts submitted for publication in the present monograph. D. Arnal, Toulouse, F F. Bertolotti, Hartford CT, USA A. Bottaro, Toulouse, F K. Dullenkopf, Karlsruhe, D M. Gaster, London, UK D. Hanel, Duisburg, D A. Hanifi, Stockholm, S D. Henningson, Stockholm, S Y. Kachanov, Novosibirsk, RUS L. Kleiser, Zurich, CH A. Leder, Rostock, D P. Luchini, Salerno, I W. Nitsche, Berlin, D M. Oberlack, Darmstadt, D U. Rist, Stuttgart, D B. Ruck, Karlsruhe, D P. Sagaut, Paris, F N. Sandham, Southampton, UK A. Savill, Cambridge, UK P. Schmid, Seattle WA, USA A. Schroder, Gottingen, D P. Spalart, Seattle WA, USA C. Tropea, Darmstadt, D P. Yoke, Guildford, UK H. Wengle, Munchen, D J. Wissink, Karlsruhe, D W. Wuerz, Stuttgart, D I. Wygnanski, Tucson AZ, USA On behalf of the Deutsche Forschungsgemeinschaft and the authors, the edi tors would like to thank all of them for their efforts and for providing con structive and useful remarks. x Contents Invited Lectures Y.S. KACHANOV: On a universal mechanism of turbulence production in wall shear flows ...................................... 1 P.J. SCHMID: A general framework for stability, receptivity and optimal control ............................................... 13 F.P. BERTOLOTTI: The equivalent forcing model for receptivity analysis with application to the construction of a high-performance skin perforation pattern for LFC .............. 25 1 Transition Mechanisms P. WASSERMANN, M. KLOKER: DNS investigations on the laminar breakdown in a three-dimensional boundary-layer flow .............................................................. 37 F.P. BERTOLOTTI, S. HEIN, W. KOCH, A. STOLTE: Absolute/convective instability investigation of primary and secondary crossflow vortices .................................. 51 D.G.W. MEYER, U. RIST, S. WAGNER: Direct numerical simulation of the development of asymmetric perturbations at very late stages of the transition process ....................... 63 S. HERR, W. WURZ, A. WORNER, U. RIST, S. WAGNER, A. IVANOV, Y. KACHANOV: Systematic investigations of 3D acoustic receptivity with respect to steady and unsteady disturbances. Experiment and DNS ............................... 75 M. KLOKER, C. STEMMER: Three-dimensional steady disturbance modes in the Blasius boundary layer - a DNS study ...................................................... 91 XI
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