Structures in contact with fluid flow, whether natural or man-made, are inevitably subject to flow-induced forces and flow-induced vibration: from plant leaves to traffic signs and to more substantial structures, such as bridge decks and heat exchanger tubes. Under certain conditions the vibration may be self-excited, and it is usually referred to as an instability. These instabilities and, more specifically, the conditions under which they arise are of great importance to designers and operators of the systems concerned because of the significant potential to cause damage in the short term. Such flow-induced instabilities are the subject of this book. In particular, the flow-induced instabilities treated in this book are associated with cross-flow, that is, flow normal to the long axis of the structure. The book treats a specific set of problems that are fundamentally and technologically important: galloping, vortex-shedding oscillations under lock-in conditions, and rain-and-wind-induced vibrations, among others. The emphasis throughout is on providing a physical description of the phenomena that is as clear and up-to-date as possible.
Author(s): Michael Paidoussis, Stuart Price, Emmanuel de Langre
Edition: 1
Publisher: Cambridge University Press
Year: 2010
Language: English
Pages: 412
Tags: Механика;Механика жидкостей и газов;
Cover......Page 1
Half-title......Page 3
Title......Page 5
Copyright......Page 6
Contents......Page 7
Preface......Page 11
1.1 General Overview......Page 13
1.2 Concepts and Mechanisms......Page 15
1.2.1 Self-excited oscillations and instabilities......Page 16
1.2.2 Argand diagrams and bifurcations......Page 20
1.2.3 Energy considerations......Page 24
1.3 Notation......Page 25
1.4 Contents of the Book......Page 26
2.1 Introductory Comments......Page 27
2.2 The Mechanism of Galloping......Page 31
2.2.1 The linear threshold of galloping......Page 32
2.2.2 Nonlinear aspects......Page 36
2.3.1 The effect of sectional shape......Page 42
2.3.2 Novak's ``universal response curve'' and continuous structures......Page 50
2.3.3 Unsteady effects and analytical models......Page 55
2.3.4 Some comments on the flow field......Page 57
2.3.5 Shear-layer reattachment......Page 61
2.4 Low-Speed Galloping......Page 62
2.5 Prisms and Cylinders with a Splitter Plate......Page 67
2.6.1 Wake breathing of the first type......Page 74
2.6.2 Wake breathing of the second type......Page 76
2.7.1 General comments......Page 78
2.7.2 Linear quasi-steady analysis......Page 79
2.7.3 Nonlinear quasi-steady analysis......Page 82
2.7.4 Disqualification of quasi-steady theory......Page 84
2.7.5 Unsteady theory......Page 87
2.8.1 Quasi-steady models......Page 89
2.9 Turbulence and Shear Effects......Page 93
2.10 Conjoint Galloping and Vortex Shedding......Page 98
2.11 Elongated and Bridge-Deck Sections......Page 102
2.12 Concluding Remarks......Page 114
3.1 Elementary Case......Page 117
3.2 Two-Dimensional VIV Phenomenology......Page 120
3.2.1 Bluff-body wake instability......Page 122
3.2.2 Wake instability of a fixed cylinder......Page 124
3.2.3 Wake of a cylinder forced to move......Page 127
3.2.4 Cylinder free to move......Page 132
3.3.1 A classification of models......Page 136
3.3.2 Type A: Forced system models......Page 139
3.3.3 Type B: Fluidelastic system models......Page 141
3.3.4 Type C: Coupled system models......Page 144
3.4.1 The issue of added mass......Page 151
3.4.2 From sectional to three-dimensional VIV......Page 158
3.4.3 VIV of noncircular cross-sections......Page 161
3.4.4 Summary and concluding remarks......Page 165
4.1 The Mechanisms......Page 167
4.1.1 Modified quasi-steady theory......Page 168
4.1.2 The damping-controlled mechanism......Page 169
4.1.3 The wake-flutter mechanism......Page 170
4.2 Wake-Induced Flutter of Transmission Lines......Page 172
4.2.1 Analysis for a fixed windward conductor......Page 174
4.2.2 Analysis for a moving windward conductor......Page 195
4.2.3 Three-dimensional effects and application to real transmission lines......Page 204
4.3 Fluidelastic Instability of Offshore Risers......Page 207
4.3.1 Experimental evidence for the existence of fluidelastic instability in riser bundles......Page 208
4.3.2 Analytical models......Page 212
5.1 Description, Background, Repercussions......Page 227
5.2.1 The damping-controlled one-degree-of-freedom mechanism......Page 232
5.2.2 Static divergence instability......Page 235
5.2.3 The stiffness-controlled wake-flutter mechanism......Page 236
5.2.4 Dependence of the wake-flutter mechanism on mechanical damping......Page 239
5.2.5 Wake-flutter stability boundaries for cylinder rows......Page 241
5.2.6 Concluding remarks......Page 242
5.3.1 Jet-switch model......Page 244
5.3.2 Quasi-static models......Page 247
5.3.3 Unsteady models......Page 251
5.3.4 Semi-analytical models......Page 261
5.3.5 Quasi-steady models......Page 266
5.3.6 Computational fluid-dynamic models......Page 273
5.3.7 Nonlinear models......Page 277
5.3.8 Nonuniform flow......Page 282
5.4 Comparison of the Models......Page 286
5.4.1 Experimental support for and against Connors' equation......Page 287
5.4.2 Comparison of theoretical models with experimental data......Page 289
5.4.3 State of the art......Page 299
6.1 A Historical Perspective......Page 303
6.2 The Vortex-Shedding Hypothesis......Page 305
6.3.1 Padoussis and Helleur's 1979 experiments......Page 308
6.3.2 In search of a new cause......Page 314
6.4.1 Further experiments with cantilevered shells......Page 316
6.4.2 Experiments with clamped-clamped shells......Page 319
6.5.1 The ``peak of resonance'' argument......Page 323
6.5.2 Have splitter plates been ineffectual?......Page 324
6.5.3 Denouement......Page 325
6.6 Simple Aeroelastic-Flutter Model......Page 326
6.6.1 Equations of motion and boundary conditions......Page 327
6.6.2 Solution of the equations......Page 329
6.6.3 Theoretical results and comparison with experiment......Page 331
6.7 A Three-Dimensional Flutter Model......Page 334
6.7.1 The model and methods of solution......Page 335
6.7.2 Theoretical results......Page 339
6.7.3 Comparison with experiment......Page 341
6.7.4 Improvements to the theory......Page 343
6.8 An Energy-Transfer Analysis......Page 346
6.9.1 The flutter model......Page 350
6.9.2 Typical results......Page 352
6.9.3 An empirical relationship for Uthr......Page 354
6.10 Concluding Remarks......Page 356
7.1.1 Field cases......Page 357
7.1.2 Wind-tunnel experiments......Page 358
7.2.1 Development of rivulets......Page 360
7.2.2 Tearing of rivulets......Page 361
7.3 VIV, Galloping and Drag Crisis......Page 363
7.4 Yamaguchi's Model: A Cylinder-Rivulet-Coupled Instability......Page 366
7.5 Concluding Remarks......Page 367
Epilogue......Page 369
Appendix A The Multiple Scales Method......Page 371
Appendix B Measurement of Modal Damping for the Shells Used in Ovalling Experiments......Page 373
References......Page 377
Index......Page 409
