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Hydrodynamics of Pumps, by Christopher Earls Brennen Hydrodynamics of Pumps HYDRODYNAMICS OF PUMPS by Christopher Earls Brennen OPEN © Concepts NREC 1994 Also available as a bound book from Concepts NREC, White River Junction, VT Published in 1994 by Concepts NREC and Oxford University Press ISBN 0-933283-07-5 (Concepts NREC) ISBN 0-19-856442-2 (Oxford University Press) http://gwaihir.caltech.edu/brennen/pumps.htm4/28/2004 3:16:03 AM Contents - Hydrodynamics of Pumps HYDRODYNAMICS OF PUMPS by Christopher Earls Brennen © Concepts NREC 1994 Preface Nomenclature CHAPTER 1. INTRODUCTION 1.1 Subject 1.2 Cavitation 1.3 Unsteady Flows 1.4 Trends in Hydraulic Turbomachinery 1.5 Book Structure References CHAPTER 2. BASIC PRINCIPLES 2.1 Geometric Notation 2.2 Cascades 2.3 Flow Notation 2.4 Specific Speed 2.5 Pump Geometries 2.6 Energy Balance 2.7 Idealized Noncavitating Pump Performance 2.8 Several Specific Impellers and Pumps References TWO-DIMENSIONAL PERFORMANCE CHAPTER 3. ANALYSIS 3.1 Introduction 3.2 Linear Cascade Analyses 3.3 Deviation Angle http://gwaihir.caltech.edu/brennen/content.htm (1 of 5)4/28/2004 3:16:06 AM Contents - Hydrodynamics of Pumps 3.4 Viscous Effects in Linear Cascades 3.5 Radial Cascade Analyses 3.6 Viscous Effects in Radial Flows References CHAPTER 4. OTHER FLOW FEATURES 4.1 Introduction 4.2 Three-dimensional Flow Effects 4.3 Radial Equilibrium Solution: an Example 4.4 Discharge Flow Management 4.5 Prerotation 4.6 Other Secondary Flows References CHAPTER 5. CAVITATION PARAMETERS AND INCEPTION 5.1 Introduction 5.2 Cavitation Parameters 5.3 Cavitation Inception 5.4 Scaling of Cavitation Inception 5.5 Pump Performance 5.6 Types of Impeller Cavitation 5.7 Cavitation Inception Data References CHAPTER 6. BUBBLE DYNAMICS, DAMAGE AND NOISE 6.1 Introduction 6.2 Cavitation Bubble Dynamics 6.3 Cavitation Damage 6.4 Mechanism of Cavitation Damage 6.5 Cavitation Noise References http://gwaihir.caltech.edu/brennen/content.htm (2 of 5)4/28/2004 3:16:06 AM Contents - Hydrodynamics of Pumps CHAPTER 7. CAVITATION AND PUMP PERFORMANCE 7.1 Introduction 7.2 Typical Pump Performance Data 7.3 Inducer Designs 7.4 Inducer Performance 7.5 Effects of Inducer Geometry 7.6 Analyses of Cavitation in Pumps 7.7 Thermal Effect on Pump Performance 7.8 Free Streamline Methods 7.9 Supercavitating Cascades 7.10 Partially Cavitating Cascades 7.11 Cavitation Performance Correlations References CHAPTER 8. PUMP VIBRATION 8.1 Introduction 8.2 Frequencies of Oscillation 8.3 Unsteady Flows 8.4 Rotating Stall 8.5 Rotating Cavitation 8.6 Surge 8.7 Auto-oscillation 8.8 Rotor-Stator Interaction: Flow Patterns 8.9 Rotor-Stator Interaction: Forces 8.10 Developed Cavity Oscillation 8.11 Acoustic Resonances 8.12 Blade Flutter 8.13 POGO Instabilities References CHAPTER 9. UNSTEADY FLOW IN HYDRAULIC SYSTEMS 9.1 Introduction http://gwaihir.caltech.edu/brennen/content.htm (3 of 5)4/28/2004 3:16:06 AM Contents - Hydrodynamics of Pumps 9.2 Time Domain Methods 9.3 Wave Propagation in Ducts 9.4 Method of Characteristics 9.5 Frequency Domain Methods 9.6 Order of the System 9.7 Transfer matrices 9.8 Distributed Systems 9.9 Combinations of Transfer Matrices 9.10 Properties of Transfer Matrices 9.11 Some Simple Transfer Matrices 9.12 Fluctuation Energy Flux 9.13 Non-cavitating Pumps 9.14 Cavitating Inducers 9.15 System with Rigid Body Vibration References CHAPTER 10. RADIAL AND ROTORDYNAMIC FORCES 10.1 Introduction 10.2 Notation 10.3 Hydrodynamic Bearings and Seals 10.4 Bearings at Low Reynolds Numbers 10.5 Annulus at High Reynolds Numbers 10.6 Squeeze Film Dampers 10.7 Turbulent Annular Seals 10.8 Labyrinth Seals 10.9 Blade Tip Rotordynamic Effects 10.10 Steady Radial Forces 10.11 Effect of Cavitation 10.12 Centrifugal Pumps 10.13 Moments and Lines of Action 10.14 Axial Flow Inducers http://gwaihir.caltech.edu/brennen/content.htm (4 of 5)4/28/2004 3:16:06 AM Contents - Hydrodynamics of Pumps References Back to front page Last updated 1/1/00. Christopher E. Brennen http://gwaihir.caltech.edu/brennen/content.htm (5 of 5)4/28/2004 3:16:06 AM Preface - Hydrodynamics of Pumps - Christopher E. Brennen HYDRODYNAMICS OF PUMPS by Christopher Earls Brennen © Concepts NREC 1994 Preface to the original hardback edition This book is intended as a combination of a reference for pump experts, and a monograph for advanced students interested in some of the basic problems associated with pumps. It is dedicated to my friend and colleague Allan Acosta, with whom it has been my pleasure and privilege to work for many years. But this book has other roots as well. It began as a series of notes prepared for a short course presented by Concepts ETI, Inc., and presided over by another valued colleague, David Japikse, the president of Concepts ETI, Inc. Another friend, Yoshi Tsujimoto, read early versions of the manuscript, and made many valuable suggestions. My thanks to all my other friends in turbomachinery research and the pump industry with whom it was my pleasure to be associated, including Dara Childs, Paul Cooper, Nick Cumpsty, Jules Dussourd, Tony Eastland, Arpad Fay, Jim Fenwick, S. Gopalakrishnan, Ed Greitzer, Loren Gross, Gene Jackson, Terry Jones, Kenjiro Kamijo, Kiyoshi Minemura, Bill Morgan, Hideo Ohashi, Sheldon Rubin, Peter Runstadler, Ed Ruth, Bruno Schiavello, Helmut Siekmann, Henry Stinson, Walt Swift and a host of others. Moreover, it was a privilege to have worked on turbomachinery problems with a group of talented students at the California Institute of Technology including Sheung-Lip Ng, David Braisted, Javier Del Valle, Greg Hoffman, Curtis Meissner, Edmund Lo, Belgacem Jery, Dimitri Chamieh, Douglas Adkins, Norbert Arndt, Ronald Franz, Mike Karyeaclis, Rusty Miskovish, Abhijit Bhattacharyya, Adiel Guinzburg and Joseph Sivo. Finally, none of this would have been possible without Doreen's encouragement, love, and companionship and that debt is beyond words. Christopher Earls Brennen, California Institute of Technology. July 1994 Preface to the Japanese translation by Yoshinobu Tsujimoto published by Osaka University Press http://gwaihir.caltech.edu/brennen/preface.htm (1 of 3)4/28/2004 3:16:06 AM Preface - Hydrodynamics of Pumps - Christopher E. Brennen I am greatly honored that Prof. Yoshi Tsujimoto has chosen to prepare this Japanese translation of ``Hydrodynamics of Pumps'' for he is a gentleman and a scholar who has my greatest admiration. Ever since we first met some 20 years ago, Yoshi and I have enjoyed a very valuable exchange of ideas and developed a deep mutual respect. Indeed, his feedback was very important to me during the preparation of the original English edition. Consequently, I am in the enviable position of knowing, with confidence, that this Japanese edition will be an improvement on the original. It also seems appropriate in this preface to acknowledge the major contributions which Japanese scientists and engineers have made to our current understanding of the hydrodynamics of pumps. In the modern era, we are all guided by the multitude of seminal ideas of Hideo Ohashi and I would like to express my deep graditude and respect to Professor Ohashi for the help he has given to so many younger engineers throughout the world. Many other Japanese pump researchers have had an important influence on my thinking and I would like to acknowledge, in particular, the help and inspiration given by Kenjiro Kamijo, Kiyoshi Minemura, Okitsugu Furuya, Hiroharu Kato, Jun-ichi Kurokawa, among others. Finally I would like to express my gratitude to Concepts ETI, Inc., to Oxford University Press and to Osaka University Press for their help in bringing the idea of this translation to reality. Christopher Earls Brennen, Pasadena, Calif. August 1997 Preface to the Internet edition Though my conversion of "Hydrodynamics of Pumps" from the hardback book to HTML is rough in places, I am so convinced of the promise of the internet that I am pleased to offer this edition freely to those who wish to use it. This new medium clearly presents some advantages and some disadvantages. The opportunity to incorporate as many color photographs as I wish (and perhaps even some movies) is a great advantage and one that I intend to use in future modifications. Another advantage is the ability to continually correct the manuscript though I will not undertake the daunting task of trying to keep it up to date. A disadvantage is the severe limitation in HTML on the use of mathematical symbols. I have only solved this problem rather crudely and apologize for this roughness in the manuscript. In addition to those whom I thanked earlier, I would like to express my thanks to my http://gwaihir.caltech.edu/brennen/preface.htm (2 of 3)4/28/2004 3:16:06 AM Preface - Hydrodynamics of Pumps - Christopher E. Brennen academic home, the California Institute of Technology, for the help in providing me the facilities to effect this conversion and to Concepts NREC for their permission to place this entire book on the internet. Christopher Earls Brennen, Pasadena, Calif. Oct.2003 Back to table of contents http://gwaihir.caltech.edu/brennen/preface.htm (3 of 3)4/28/2004 3:16:06 AM Nomenclature - Hydrodynamics of Pumps - Christopher E. Brennen HYDRODYNAMICS OF PUMPS by Christopher Earls Brennen © Concepts NREC 1994 Nomenclature ROMAN LETTERS a Pipe radius A Cross-sectional area Aijk Coefficients of pump dynamic characteristics [A] Rotordynamic force matrix Ar Cross-sectional area ratio B Breadth of passage or flow [B] Rotordynamic moment matrix c Chord of the blade or foil c Speed of sound c Rotordynamic coefficient: cross-coupled damping cb Interblade spacing cPL Specific heat of liquid C Compliance C Rotordynamic coefficient: direct damping CD Drag coefficient CL Lift coefficient Cp Coefficient of pressure Cpmin Minimum coefficient of pressure d Ratio of blade thickness to blade spacing D Impeller diameter or typical flow dimension Df Diffusion factor DT Determinant of transfer matrix [T] e Specific internal energy E Energy flux http://gwaihir.caltech.edu/brennen/nomen.htm (1 of 7)4/28/2004 3:16:13 AM Nomenclature - Hydrodynamics of Pumps - Christopher E.
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