Egon Krause

Fluid Mechanics

With Problems and Solutions, and an Aerodynamic Laboratory

With 607 Figures

Prof. Dr. Egon Krause RWTH Aachen Aerodynamisches Institut W¨ llnerstr.5-7 u 52062 Aachen Germany

ISBN 3-540-22981-7 Springer Berlin Heidelberg New York

Library of Congress Control Number: 2004117071 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, recitation, broadcasting, reproduction on microﬁlm or in other ways, and storage in data banks. Duplication 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 to prosecution under German Copyright Law. Springer is a part of Springer Science+Business Media springeronline.com c Springer-Verlag Berlin Heidelberg 2005 Printed in Germany

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Preface

During the past 40 years numerical and experimental methods of ﬂuid mechanics were substantially improved. Nowadays time-dependent three-dimensional ﬂows can be simulated on high-performance computers, and velocity and pressure distributions and aerodynamic forces and moments can be measured in modern wind tunnels for ﬂight regimes, until recently not accessible for research investigations. Despite of this impressive development during the recent past and even 100 years after Prandtl introduced the boundary-layer theory, the fundamentals are still the starting point for the solution of ﬂow problems. In the present book the important branches of ﬂuid mechanics of incompressible and compressible media and the basic laws describing their characteristic ﬂow behavior will be introduced. Applications of these laws will be discussed in a way suitable for engineering requirements. The book is divided into the six chapters: Fluid mechanics I and II, exercises in ﬂuid mechanics, gas dynamics, exercises in gasdynamics, and aerodynamics laboratory. This arrangement follows the structure of the teaching material in the ﬁeld, generally accepted and approved for a long time at German and foreign universities. In ﬂuid mechanics I, after some introductory statements, incompressible ﬂuid ﬂow is described essentially with the aid of the momentum and the moment of momentum theorem. In ﬂuid mechanics II the equations of motion of ﬂuid mechanics, the Navier-Stokes equations, with some of their important asymptotic solutions are introduced. It is demonstrated, how ﬂows can be classiﬁed with the aid of similarity parameters, and how speciﬁc problems can be identiﬁed, formulated and solved. In the chapter on gasdynamics the inﬂuence of variable density on the behavior of subsonic and supersonic ﬂows is described. In the exercises on ﬂuid mechanics I and II and on gasdynamics the material described in the previous chapters is elaborated in over 200 problems, with the solutions presented separately. It is demonstrated how the fundamental equations of ﬂuid mechanics and gasdynamics can be simpliﬁed for the various problem formulations and how solutions can be constructed. Numerical methods are not employed. It is intended here, to describe the fundamental relationships in closed form as far as possible, in order to elucidate the intimate connection between the engineering formulation of ﬂuid-mechanical problems and...